Incidence of Bone Metastases

Bone is the most common site for metastasis in cancer and is of particular clinical importance

in breast and prostate cancers because of the prevalence of these diseases. At postmortem

examination, f70% of patients dying of these cancers have evidence of metastatic bone

disease (Table 1;ref. 1). However, bone metastases may complicate a wide range of

malignancies, resulting in considerable morbidity and complex demands on health care

resources. Carcinomas of the thyroid, kidney, and bronchus also commonly give rise to bone

metastases, with an incidence at postmortem examination of 30% to 40%. However, tumors

of the gastrointestinal tract rarely (<10%) produce bone metastases.

Distribution of Bone Metastases

Bone metastases most commonly affect the axial skeleton. The axial skeleton contains the red

marrow in the adult, which suggests that properties of the circulation, cells, and extracellular

matrix within this region could assist in the formation of bone metastases. Evidence exists

that blood from some anatomic sites may drain directly into the axial skeleton. In postmortem

studies of animals and humans, Batson (2) showed that venous blood from the breasts and

pelvis flowed not only into the venae cavae but also into a vertebral-venous plexus of vessels

that extended from the pelvis throughout the epidural and perivertebral veins.The drainage of

blood to the skeleton via the vertebral-venous plexus may, at least in part, explain the

tendency of breast and prostate cancers, as well as those arising in kidney, thyroid, and lung,

to produce metastases in the axial skeleton and limb girdles. Of course, the vertebral-venous

plexus does not provide the entire explanation of why these cancers metastasize to the

skeleton. Molecular and cellular biological characteristics of the tumor cells and the tissues to

which they metastasize are of paramount importance and influence the pattern of metastatic

spread (3–5).

Prognosis

In many patients, metastatic bone disease is a chronic condition with an increasing range of

specific treatments available to slow the progression of the underlying disease. The survival

from the time of diagnosis varies among different tumor types. The median survival time

from diagnosis of bone metastases from prostate cancer or breast cancer is measurable in

years (4, 6). In contrast, the median survival time from the diagnosis of advanced lung cancer

is typically measured in months. The prognosis after the development of bone metastases in

breast cancer is considerably better than that after a recurrence in visceral sites. For example,

in a study by Coleman and Rubens (4) of patients whose cancers were diagnosed in the 1970s

and 1980s and who were treated at a single institution, the median survival was 24 months in

those patients with first recurrence in the skeleton compared with 3 months after first relapse

in the liver (P < 0.00001). Coexisting nonosseous metastatic disease is important in

determining prognostic differences between patients with bone metastases from the same

type of tumor. Additionally, for patients with advanced breast cancer and metastatic disease

confined to the skeleton at first relapse, the probability of survival is influenced by the

subsequent development of metastases at extraosseous sites. In a study of 367 patients with

bone metastases from breast cancer, those who later developed extraosseous disease had a

median survival of 1.6 years compared with 2.1 years for those with disease that remained

clinically confined to the skeleton.

Clinical Features

Skeletal metastatic disease is the cause of considerable morbidity in patients with advanced

cancer. The frequency of skeletal complications (also known as skeletal-related events)

across a range of tumor types receiving standard systemic treatments but no bisphosphonates

is shown in Fig. 2 (20). On average, a patient with metastatic disease will experience a

skeletal-related event every 3 to 6 months. However, the occurrence of these morbid events is

not regular, with eventsclustering around periods of progression and becoming more

frequent as the disease becomes more extensive and the treatment options reduce.

Pain. Bone metastases are the most common cause of cancer-related pain (21). The

pathophysiologic mechanisms of pain in patients with bone metastases are poorly understood

but probably include tumor-induced osteolysis, tumor production of growth factors and

cytokines, direct infiltration of nerves, stimulation of ion channels, and local tissue

production of endothelins and nerve growth factors. Although f80% of patients with

advanced breast cancer develop osteolytic bone metastases, approximately two thirds of such

sites are painless (22). Different sites of bone metastases are associated with distinct clinical

pain syndromes. Common sites of metastatic involvement associated with pain are the base of

skull (in association with cranial nerve palsies, neuralgias, and headache), vertebral

metastases (producing neck and back pain with or without

neurologic complications secondary to epidural extension), and pelvic and femoral lesions

(producing pain in the back and lower limbs, often associated with mechanical instability and

incident pain).

Hypercalcemia. Hypercalcemia most often occurs in those patients with squamous cell lung

cancer, breast and kidney cancers, and certain hematologic malignancies (in particular

myeloma and lymphoma). In most cases, hypercalcemia is aresult of bone destruction, and

osteolytic metastases are present in 80% of cases. In breast cancer, an association exists

between hypercalcemia and the presence of liver metastases (23). This association may

reflect a relationship between liver involvement and production or reduced metabolism of

humoral factors with effects on bone such as parathyroid hormone–related peptide or receptor

activator of nuclear

factor-nB ligand. Secretion of humoral and paracrine factors by tumor cells stimulates

osteoclast activity and proliferation, and there is a marked increase in markers of bone

turnover (24). Several

studies have established the role of parathyroid hormone– related peptide in most cases of

malignant hypercalcemia (25). The levels of circulating parathyroid hormone–related peptide

are elevated in two thirds of patients with bone metastases and hypercalcemia and in almost

all patients with humoral

hypercalcemia. The kidney also has a role in malignant hypercalcemia;as a result of volume

depletion and the action of parathyroid hormone–related peptide, renal tubular reabsorption

of calcium is increased, further increasing serum calcium levels.

The signs and symptoms of hypercalcemia are nonspecific, and the clinician should have a

high index of suspicion. Common symptoms include fatigue, anorexia, and constipation. If

untreated, a progressive increase in serum calcium level results in deterioration of renal

function and mental status. Death ultimately results from renal failure and cardiac

arrhythmias.

Pathologic fractures. The destruction of bone by metastatic disease reduces its load-bearing

capabilities and results initially in microfractures, which cause pain. Subsequently, fractures

occur (most commonly in ribs and vertebrae). It is the fracture of a long bone or the epidural

extension of tumor into the spine that causes the most disability. As the development of a

longbone fracture has such detrimental effects on quality of life in patients with advanced

cancer, efforts have been made to predict sites of fracture and to preempt the occurrence of a

fracture by prophylactic surgery. Fractures are common through lytic lesions in weight-

bearing bones. Damage to both cortical and trabecular bone is structurally important. Several

radiological features have been identified that may predict imminent fracture;fracture is likely

if lesions are large, are predominantly lytic, and erode the cortex. A scoring system has been

proposed by Mirels based on the site, nature, size, and symptoms from a metastatic deposit

(26). Using this system, lesions that scored >7 generally require surgical intervention;deposits

that scored z10 had an estimated risk of fracture of >50%. More sophisticated predictive tools

based on computed tomography of sites at risk of fracture are currently under evaluation.

Compression of the spinal cord or cauda equina. Spinal cord compression is a medical

emergency, and suspected cases require urgent evaluation and treatment. Pain occurs in most

patients, is localized to the area overlying the tumor,

and often worsens with activities that increase intradural pressure (e.g., coughing, sneezing,

or straining). The pain is usually worse at night, which is the opposite pattern of pain

from degenerative disease. There may also be radicular pain radiating down a limb or around

the chest or upper

abdomen. Local pain usually precedes radicular pain andmay predate the appearance of other

neurologic signs by weeks or months. Most patients with spinal cord compression will have

weakness or paralysis. Late sensory changes include numbness and anesthesia distal to the

level of involvement. Urinary retention, incontinence, and impotence are usually late

manifestations of cord compression. However, lesions at the level of the conus medullaris can

present with early autonomic dysfunction of the bladder, rectum, and genitalia.

In a retrospective analysis of 70 patients with spinal cord compression secondary to breast

cancer, the most frequent symptom was motor weakness (96%) followed by pain (94%),

sensory disturbance (79%), and sphincter disturbance (61%;ref. 27). Ninety-one percent of

patients had at least one symptom for >1 week;96% of those ambulant before therapy

maintained the ability to walk. In those unable to walk, 45% regained ambulation, with

radiotherapy and surgery equally effective. Median survival was 4 months.The most

important predictor of survival was the ability to walk after treatment. These results suggest

that earlier diagnosis and intervention may improve both outcome and survival.

Spinal instability. Back pain is a frequent symptom in patients with advanced cancer and in

10% of cases is due to spinal instability. The pain, which can be severe, is mechanical in

origin, and frequently the patient is only comfortable when lying still. Surgical stabilization is

often required to relieve the pain, and although such major surgery is associated with

considerable morbidity and mortality, excellent results can be obtained with appropriate

patient selection.

INITIAL EVALUATION

The evaluation of a patient who definitely or potentially has a hip fracture involves reviewing

the patient's medical history, performing a physical examination, and carrying out

radiographic studies. The radiographic studies are used to determine the exact location

(Figure 1) and degree of displacement of the fracture; this information can help clinicians to

differentiate the various subtypes of proximal femoral fracture (e.g., intertrochanteric, femoral

neck, subtrochanteric, greater trochanteric).

The patient's symptoms and the physical examination findings usually depend on the type of

fracture and its degree of displacement. For most proximal femoral fractures, ecchymosis

generally appears during the first few days after the fractures occur. However, ecchymosis

may not develop with femoral neck fractures because the fracture hematoma may be

contained within the hip capsule.

Fractures of the proximal femur that are incomplete or nondisplaced may cause only minimal

pain with movement and weight bearing. However, clinical evidence of such fractures can be

obtained by using the Stinchfield test.12 With this test, the patient lies in a supine position and

attempts to lift the affected leg against gravity and then against weight resistance. If groin or

thigh pain is elicited during either of these exercises, the test is positive. Patients with

displaced fractures of the proximal femur usually cannot bear weight and report pain with

even slight movement of the affected extremity. The displaced fracture usually causes the leg

to shorten and become abducted and externally rotated to some degree.13 Furthermore, there

may be pain or crepitation with palpation of the lateral femur and trochanter.

Most fractures of the proximal femur can be observed on plain radiographs. Standard views

include an anteroposterior (AP) view of the pelvis and a true lateral view of the hip. With

respect to hard-to-see fractures, another view that may be helpful is an AP view obtained with

the hip internally rotated approximately 15 degrees.13 Magnetic resonance imaging (MRI) and

technetium bone scans may also prove useful. Although bone scans have a high sensitivity in

diagnosing fractures 48 to 72 hours after they occur, MRI has been found to be 100%

sensitive, can be used to identify fractures sooner, and is very useful for finding occult

fractures.3 Patients with acute hip pain and normal results on plain radiographs must be

assumed to have a hip fracture until proven otherwise; MRI or a technetium bone scan may be

needed to confirm the diagnosis of a symptomatic, nondisplaced fracture.14–21 If the hip joint is

irritable on physical examination, limited MRI is the best technique to confirm a fracture

within the first 2 to 3 days after it is thought to have occurred. If the patient's pain is more

diffuse, a technetium bone scan of the pelvis, lumbar spine, and hips may be preferred; a 3-

day interval between the injury and the performance of this test is necessary to allow

sufficient sensitivity. During this 3-day period, patients should practice protected weight

bearing and should receive treatment for pain.

GENERAL TREATMENT CONSIDERATIONS

The goal of treatment is to limit pain and to help the patient return to the level of activity he or

she had prior to sustaining the fracture. Efforts to attain this goal may or may not involve

surgery. Non-operative treatment is usually reserved for impacted or nondisplaced proximal

femoral fractures. The premise behind non-operative treatment is that if the patient can be

mobilized and his or her pain controlled, the risk of complications such as skin breakdown

and pulmonary illness is decreased. However, the risk of displacement of the fracture must

also be considered. In cases of femoral neck fractures, operative treatment is favored to avoid

displacement and possible avascular necrosis of the hip. For most proximal femoral fractures,

operative treatment is more appropriate.

Figure 1. Anatomic regions relating to areas of proximal femoral fractures.

Although hip fractures in young patients may be complicated by medical issues, surgical

treatment for these individuals is typically emergent. However, for elderly patients, who

sometimes have cardiac, pulmonary, and psychiatric co-morbidities, an immediate surgical

procedure may initially carry too high a risk for substantial morbidity and mortality. Prior to

surgery, elderly patients need to be medically evaluated to minimize any potential risks of

surgery. Medical work-up usually involves evaluating the patient for hypertension, heart

disease (including coronary artery disease, dysrhythmias, and congestive heart failure),

diabetes mellitus, chronic obstructive pulmonary disease, cerebral vascular disease, and

urinary tract infection.

The time needed to perform a complete medical evaluation and treat or manage co-

morbidities in elderly patients can delay surgery for at least 12 to 24 hours.7 Although there is

conflicting evidence about the mortality rate if surgery is delayed for 24 hours or less, there is

substantial evidence suggesting that if surgery is postponed for more than 3 days, the

mortality rate within the first year after this treatment doubles.3,22–27 It may be true, however,

that the patients who experience a delay of more than 3 days in undergoing their surgical

procedure are the most ill on presentation. Furthermore, prolonging the time before surgery

increases the risk of skin breakdown, urinary tract infection, deep vein thrombosis (DVT), and

pulmonary complications.1

Moreover, if a patient, regardless of age, is receiving anticoagulation therapy because of atrial

fibrillation, valve replacement, history of transient ischemic attacks, or other reasons, reversal

of this therapy may be appropriate before the surgical procedure is performed. In general,

anticoagulation therapy can be reversed by administering fresh frozen plasma or vitamin K

(i.e., phytonadione). However, fresh frozen plasma is usually transient in its effect and can be

associated with transfusion reactions and other problems. Moreover, reversal of the

anticoagulative effect of warfarin with vitamin K can be complicated by thrombosis, and

doses of vitamin K greater than 10 mg can lead to warfarin resistance for as long as a week.25

If a patient has been receiving warfarin, the prothrombin time and international normalized

ratio (INR) can be allowed to normalize by simply discontinuing the warfarin. In patients with

a history of transient ischemic attacks, cardiomyopathy, and atrial fibrillation, discontinuation

of warfarin is unlikely to lead to an adverse event.26 However, in patients with prosthetic heart

valves whose warfarin anticoagulation therapy is being reversed, unfractionated heparin

should be administered as the INR decreases to an acceptable level; the heparin can then be

discontinued hours prior to surgery.26

Prior to surgery for hip fractures, most patients—irrespective of age—are confined to bed.

During this time, they most likely will require an analgesic agent, which can contribute to the

increased mental status changes seen in elderly patients. To help with the discomfort of a

displaced fracture, 5 lb of longitudinal (Buck's) skin traction can be used, although pillow

support alone has been shown to be just as effective.28 If surgery is delayed for a considerable

amount of time, DVT prophylaxis is indicated and can include graduated compression

stockings; sequential pneumatic calf, thigh, or ankle pumps; and low-molecular-weight

heparin.

INTERTROCHANTERIC FRACTURES

General Characteristics

Intertrochanteric fractures occur in the transitional bone between the femoral neck and the

femoral shaft (Figure 1).27 These fractures may involve both the greater and the lesser

trochanters. Transitional bone is composed of cortical and trabecular bone. These bone types

form the calcar femorale posteromedially, which provides the strength to distribute the

stresses of weight bearing. Consequently, the stability of intertrochanteric fractures depends

on the preservation of the postero-medial cortical buttress.29 Osteonecrosis is uncommon

because these fractures usually do not disturb the femoral head blood supply. Moreover,

because transitional bone is highly vascular, complications such as nonunions are uncommon

as well.27

Classification

The most often used classification system for intertrochanteric fractures is based on the

stability of the fracture pattern and the ease in achieving a stable reduction.27 This

classification was introduced by Evans in 1949 and accurately differentiates stable fractures

(standard oblique fracture pattern) from unstable fractures (reverse oblique fracture pattern)

(Figure 2). It is important to identify a reverse oblique fracture because this type of fracture

should not be treated with a standard compression plate. The stability of intertrochanteric

fractures depends on the integrity of the posteromedial cortex, and instability increases with

comminution of the fracture, extension of the fracture into the sub-trochanteric region, and the

presence of a reverse oblique fracture pattern.27

Figure 2. Simplified Evans' classification of intertrochanteric fractures: standard oblique

fracture (stable) and reverse oblique fracture (unstable).

Treatment

Surgery is the mainstay of treatment for both displaced and nondisplaced intertrochanteric

fractures. The primary reason for surgery is to allow the early mobilization of the patient, with

partial weight-bearing restrictions depending on the stability of the reduction.27 The most

common internal fixation device used today is the sliding screw-plate device (Figure 3).27

This implant consists of a large lag screw placed in the center of the femoral neck and head

and a side plate along the lateral femur. The screw-plate interface angle is variable and

depends on the anatomy of the patient and the fracture. The advantage of the sliding lag

screw, compared with a static screw, is that it allows for impaction of the fragments; this

impaction increases the bone-on-bone contact, promoting osseous healing while decreasing

implant stress.27 The disadvantage is common shortening and rotation at the fracture site.

Although repair of an intertrochanteric fracture is often referred to as open reduction with

internal fixation (ORIF), the term closed reduction with internal fixation (CRIF) may be more

accurate. The patient rests in a supine position on a fracture table that allows the affected leg

to be placed in traction. The fracture is anatomically reduced by longitudinal traction and

rotation of the leg.27 An incision is made, and after the bone is exposed, the lag screw is placed

into the center of the femoral neck and head with fluoroscopic guidance. Optimally, the end of

the lag screw should be placed in close proximity to the apex of the femoral head so that the

sum of the distances between the end of the screw and the apex of the femoral head in the AP

and lateral views is less than 20 to 25 mm.30,31 By doing this, the occurrence of the

complication known as "cut out" of the lag screw from the femoral head can be almost

completely prevented.30,31 The next step is placement of the sliding side plate device, which is

fixed to the shaft of the femur by using cortical screws.

CRIF of intertrochanteric fractures may allow for immediate weight bearing.27 Depending on

the stability of the fracture and its fixation, touchdown weight bearing or partial weight

bearing is usually recommended for 4 to 6 weeks after the surgical procedure. When signs of

healing are apparent and fracture collapse has diminished, weight-bearing status is usually

increased. Long-term problems after these fractures are healed include malrotation, abductor

muscle biomechanical abnormalities, pain (owing to the hardware), and shortening of the leg

at the fracture site (because of collapse).

FEMORAL NECK FRACTURES

General Characteristics

Femoral neck fractures occur between the end of the articular surface of the femoral head and

the inter-trochanteric region (Figure 1).32 These fractures are intracapsular, and hip synovial

fluid may interfere with their healing.3 Healing may also be affected by disruption of the

arterial blood supply to the fracture site and the femoral head; with femoral neck fractures, the

lateral ascending cervical branches of the medial femoral circumflex artery are at risk for

disruption. Loss of this blood supply increases the risk of nonunion at the fracture site and the

risk for avascular necrosis of the femoral head.

Figure 4. Garden classification system of femoral neck fractures. (A) Garden I fracture:

incomplete and minimally displaced. The fracture shown is impacted and is in valgus

malalignment. (B) Garden II fracture: complete, nondisplaced. (C) Garden III fracture:

complete fracture and partially displaced. The fracture shown is in varus malalignment. (D)

Garden IV fracture: completely displaced, with no engagement of the 2 principal fragments.

Classification

The most commonly used classification system for femoral neck fractures is the Garden

system (Figure 4).3 The Garden system is based on the amount of displacement of the

fractures. Garden I fractures are minimally displaced and incomplete and are usually impacted

with the femoral head tilting in the posterolateral direction. Garden II fractures are complete

but nondisplaced. Garden III fractures are complete and partially displaced, and Garden IV

fractures are completely displaced.3 Although the Garden system is the most commonly used

system of classification, there is much inter-observer variability.3

Treatment

Operative treatment is favored for femoral neck fractures. The specific type of operative

treatment depends on the age of the patient and the characteristics of the fracture (eg, location,

displacement, degree of comminution).1 In young patients, it is necessary to obtain reduction

of the femoral neck fracture as soon as possible to decrease the risk of avascular necrosis.3

Anatomic reduction and subsequent fixation are the goals of surgery. Young patients usually

undergo closed or open reduction, with percutaneous placement of 3 parallel cannulated lag

screws (Figure 5). The procedure is performed with the patient in a supine position on a

fracture table. The parallel cannulated lag screws allow compression at the fracture site and

maintain reduction while the fracture heals. Elderly patients who have Garden I or II fractures

also benefit from parallel cannulated screw fixation, although this is usually performed in situ.

Hemiarthroplasty is the procedure of choice for elderly patients with displaced femoral neck

fractures. The previous activity level of the patient is important in determining the exact type

of hemiarthroplasty to perform.3 Independent ambulators benefit from a cemented

hemiarthroplasty, because pain after surgery and component loosening are minimal with this

approach. Hemiarthroplasty is most often performed with patients in the lateral decubitus

position. After the incision is made and the joint exposed, the femoral head is extracted and

the femoral neck is cut to allow placement of the prosthesis. There are many different

prosthetic devices, ranging from unipolar devices (including the Austin-Moore prosthesis) to

bipolar devices (Figure 6). The majority of these prostheses are cemented; however, in

elderly patients, who usually have compromised cardiopulmonary reserves, excessive

pressurization of the cement is avoided to prevent further metabolic and mechanical insult.3

Figure 5. (A) Radiograph (anteroposterior view) of a valgus, impacted (Garden I) femoral

neck fracture treated by way of internal fixation with 3 parallel cannulated lag screws. (B)

Schematic representation of screw configuration as viewed from the side.

Figure 6. Radiograph (anteroposterior view) of a displaced femoral neck fracture treated by

way of femoral head replacement with a bipolar prosthetic device.

Weight bearing after surgery for patients of all ages is dependent on the fracture type, patient

demands and compliance, and surgeon preference. In general, patients who have undergone

reduction and fixation with cannulated lag screws usually have a restricted weight-bearing

status after the procedure. In contrast, patients who have undergone hemiarthroplasty can be

allowed to bear weight as tolerated; certain restrictions of position are encouraged to prevent

dislocation.

SUBTROCHANTERIC FRACTURES

General Characteristics

Subtrochanteric fractures occur between the lesser trochanter and the isthmus of the diaphysis

of the femur (Figure 1).3 These fractures are less common than femoral neck and

intertrochanteric fractures.

Classification

Classification systems for subtrochanteric fractures have evolved in relation to the

development of new treatment devices. Early classification systems were based on the

location of the fracture and the number of fracture fragments.3 With the advent of special

intramedullary rods that can be used to treat these fractures, the Russell-Taylor classification

system was established.

The Russell-Taylor system is based on the lesser trochanter continuity and whether the

fracture extends posteriorly into the greater trochanter and involves the piriformis fossa

(Figure 7)3; this system comprises 2 types of fractures. These fracture types can be

differentiated on the basis of the appropriate use of the intramedullary nail. For type I

fractures, which do not extend into the piriformis fossa, closed intramedullary nailing has the

advantage of minimizing vascular compromise of the fragments.3 In contrast, type II fractures

involve the greater trochanter and the piriformis fossa, making use of closed intramedullary

nailing less favorable.3

Figure 7. Russell-Taylor classification of subtrochanteric fractures. Type I fractures do not

extend into the piriformis fossa, and thus, intramedullary nailing can be beneficial. Type II

fractures extend proximally into the greater trochanter and involve the piriformis fossa; this

involvement complicates closed intramedullary nailing techniques.

Treatment

Treatment options for subtrochanteric fractures include nonoperative and operative methods.

However, as with intertrochanteric and femoral neck fractures, the mainstay of treatment is

surgery. The goal of treatment is fracture reduction so that near anatomic alignment and

normal femoral anteversion are obtained. One option involves use of an intramedullary nail

with interlocking hardware that extends into the femoral neck. Another option involves a

fixed angle extramedullary device, such as a 95-degree lag screw and side plate or blade plate

(Figure 8).

The screw and side plate and blade plate have been shown to have high rates of fracture union

when used with fractures involving the piriformis fossa, but intramedullary nails have been

recommended if the posteromedial cortical buttress cannot be established in unstable

fractures.3 It has also be suggested that the fixed angle extramedullary devices do not allow

compression at the fracture site3; however, with the use of a plate tensioning device, this can

be overcome.

After fracture fixation, the patient usually requires protected weight bearing for 6 to 12 weeks,

and as callous formation is observed radiographically, weight bearing is slowly increased.

Operative treatment allows for immediate mobilization and pain management and decreases

the risk of complications such as skin breakdown, DVT, and pulmonary abnormalities.

Figure 8. Radiograph (anteroposterior view) of a sub-trochanteric fracture treated by way of

internal fixation with a blade plate.

GREATER TROCHANTERIC FRACTURES

General Characteristics

The greater trochanter is the insertion site of the gluteus medius and gluteus minimus (which

aid in hip abduction) and the insertion site of the piriformis, obturator internus, and gemelli

muscles (which aid in hip rotation) (Figure 1).

Classification

There are 2 common types of greater trochanteric fractures. The first and most common is

avulsion of the greater trochanteric apophysis of the femur, which occurs in skeletally

immature patients.13 This fracture usually occurs from a powerful muscle contraction of the

lateral hip rotators and is usually minimally displaced.13 The second type of greater

trochanteric fracture usually occurs in an elderly patient who has osteoporosis and results

from direct trauma, such as a fall.3 These fractures are most commonly minimally displaced,

but the portion of the bone attached to the piri-formis muscle can be markedly displaced.

Treatment

Both types of fracture can be treated conservatively with protected weight bearing on the

affected leg until the symptoms resolve.3,13 However, a nondisplaced greater trochanteric

fracture that results from a fall needs to be evaluated to confirm that the fracture does not

extend into the intertrochanteric region, which could result in displacement of the fracture. To

evaluate the fracture, limited MRI3 or a bone scan may be useful. If the trochanteric fracture

involves a large, completely displaced, and mechanically significant fragment of bone, it may

require reduction and fixation. Screws, cable devices, and tension band techniques have all

been advocated in such cases to reattach the insertion site of the hip abductors and hip rotators

to the proximal femur.

PROGNOSIS OF PROXIMAL FEMORAL FRACTURES

Most of the studies evaluating the prognosis of proximal fractures of the femur compare

intertrochanteric fractures with femoral neck fractures. In the surgical treatment of

intertrochanteric fractures, "cut out" of the implanted hardware is a preventable complication.

However, following surgery, loss of fixation of any type is less than 15% for both

intertrochanteric and femoral neck fractures.1 Other complications of surgical treatment of

proximal femoral fractures, such as nonunion and osteonecrosis, occur more often with

femoral neck fractures than with intertrochanteric fractures.1

Complications that occur with hemiarthroplasty for femoral neck fractures include dislocation

of the prosthesis in addition to prosthesis loosening. The dislocation rate is related to

technique, but the overall incidence is low and can be decreased with strict hip-movement

precautions taught to the patient by the physical and occupational therapists.

Hospital stays tend to be longer for patients with intertrochanteric fractures, as opposed to

femoral neck fractures; likewise, a higher portion of patients with intertrochanteric fractures

require placement in a nursing home.2 Furthermore, although the overall 1-year mortality rate

is the same among patients with inter-trochanteric fractures and those with femoral neck

fractures, patients with intertrochanteric fractures have a slower recovery rate and a higher

mortality rate in the hospital at 2 months and at 6 months.2

Elderly men are twice as likely to die soon after a hip fracture than are elderly women. In a

study of 804 community-dwelling patients, 31% of the men died within 1 year of sustaining a

hip fracture and 42% within 2 years.33 In comparison, only 15% of the women in the study

died within 1 year and 23% within 2 years.33

PREVENTION OF HIP FRACTURES

Recovery from a hip fracture is complex and multidimensional: substantial losses in

contralateral hip bone mineral content, lean body mass, and performance and function are not

fully rectified in most cases. Therefore, prevention is important, especially for an aging

population. By 2020 the estimated number of proximal femoral fractures expected to occur in

the United States is 350,000 per year—and by 2040, between 530,000 and 840,000 fractures

are expected to occur.2

Two preventive strategies to deal with this epidemic are the use of passive protective

garments and prevention and treatment of osteoporosis. Passive protection through the use of

hip pads has recently been demonstrated, and a gel pad with a rigid cover has been shown to

diminish the impact of falls.34 Current research is focusing on who should wear these garments

and the best way to increase patient comfort and compliance.

The prevention and treatment of osteoporosis may significantly decrease the risk for hip

fracture. It is particularly important to address this issue with respect to all elderly patients

being treated for their first hip fracture. The incidence of hip fractures is increased among

women older than 60 years who have sustained a hip fracture in the past. Bone mineral

density measured at the femoral neck by dual energy x-ray absorptiometry may be the best

predictor of hip fracture. Awareness of osteoporosis and a multifaceted team approach to

osteoporosis prevention and treatment are the best strategy to prevent fractures.

Intoduction

Pathologic fractures can be caused by any type of bone tumor, but the overwhelming

majority of pathologic fractures in the elderly are secondary to metastatic carcinomas.

Multiple myeloma is also common in the elderly and has a high incidence of pathologic

fractures. Diagnostic laboratory tests and imaging of multiple myeloma and metastatic tumors

allow earlier diagnosis and intervention, which lead to decreased morbidity. Chemotherapy

and radiation therapy have improved treatment of metastatic disease, but have a variable

effect depending on the tumor type. The goals of surgical treatment of impending or

pathologic fracture are to provide pain relief and a functionally stable and durable construct

that will allow the patient to ambulate shortly after surgery and will persist for the life of the

patient. Fixation of metastatic pathologic fractures requires reinforcement or replacement of

the compromised bone with a rigid and durable construct. Rehabilitation and prevention of

postoperative complications are imperative. The overall effectiveness of treatment in

pathologic fractures is improved with a multidisciplinary approach.

Many pathologic processes, including osteoporosis, weaken bone. Typically, the term

pathologic fracture refers to the fracture that occurs in the area of a neoplasm. Pathologic

fractures can be caused by any type of bone tumor, but the overwhelming majority of

pathologic fractures in the elderly are secondary to metastatic carcinomas. Multiple myeloma

is also common in the elderly and has a high incidence of pathologic fractures.

Metastatic Tumors of Bone

The most common primary malignancies that metastasize to bone are breast, lung,

kidney, prostate, and thyroid carcinomas, which account for approximately 700,000 new

primary cases in the U.S. annually. Metastatic bone disease can have very detrimental effects

on quality of life. The prognosis for patients with metastases to bone largely depends on the

aggressiveness of the primary tumor, with lung cancer patients having the shortest length of

survival. Unlike primary bone tumors, the early diagnosis and treatment of secondary tumors

will not result in a cure. However, much of the significant morbidity related to bone

metastases and pathologic fracture can be lessened with early intervention. The evaluation

and management of patients with metastatic bone disease is best done with a

multidisciplinary approach including medical oncologist, radiologist, pathologist, orthopedic

surgeon, physical therapist, and social worker.

Location

Skeletal metastases are often multifocal; however, breast, renal and thyroid

carcinomas are notorious for producing solitary lesions. By far the most common location for

osseous metastases is the axial skeleton, followed by the proximal femur and proximal

humerus. Metastatic spine tumors are 40 times more frequent than all primary bone tumors

combined [1]. In autopsy series, vertebral body metastases were found in over one-third of

patients who died of cancer [2]. The anterior elements of the spine are 20 times more likely to

be involved than the posterior elements [3].

Presentation

Patients with metastatic bone disease can have varied presentations. Lesions may vary

from extremely painful and disabling to asymptomatic. Most metastases present with a bone

lesion detected on bone imaging after patients complain of localized musculoskeletal pain.

Bone metastases rarely present with an associated soft-tissue mass, and the presence of such a

mass should increase the suspicion of a primary sarcoma. Fractures after a minor or

insignificant injury should always raise the suspicion of an underlying lesion, especially in

patients with a previously diagnosed malignancy.

Most symptomatic patients with metastatic bone disease present with pain that is

mechanical in nature, worse at night, and unresponsive to anti-inflammatory medications and

narcotics. Neurological complaints may be the presenting symptoms especially in cases of

spinal metastases with associated nerve root or spinal cord compression. It is also common

for patients with pelvic metastases to present with leg pain, which mimics sciatica. As such, it

is important to include imaging of the pelvis in the work-up of patients with metastatic bone

disease and leg pain because radiographs and magnetic resonance imaging (MRI) of the

lumbar spine may miss these lesions. Thorough clinical examination is mandatory in all cases

to evaluate not only the presenting lesion, but also any other metastatic foci that may be less

symptomatic. In patients with previous bony metastasis, regular follow-up evaluation is

needed to assess painful sites and screen for impending fractures.

Diagnostic Laboratory Tests

The laboratory work-up in a patient with a metastatic bone tumor can be involved if

the primary tumor has not already been diagnosed. A complete blood count (CBC) with a

differential is important when working up any suspected malignancy. Elevated erythrocyte

sedimentation rates (ESR) and C-reactive protein (CRP) levels signal that an inflammatory

process is involved, but cannot consistently differentiate an infectious process from a

malignancy. Carcinoembryonic antigen (CEA) is a marker of adenocarcinomas from various

primary sites such as colonic, rectal, pancreatic, gastric, and breast. Prostate-specific antigen

(PSA) levels can help diagnose prostate cancer. A thyroid panel can help eliminate the

suspicion of a rare thyroid primary. Lactate dehydrogenase (LDH) isoenzymes 2 and 3 can

suggest a diagnosis of lymphoma. To evaluate for liver cancer, alpha fetal protein (AFP)

levels are often obtained in patients with hepatitis C or those that are heavy drinkers. A

chemistry panel can be used to assess kidney function and allows calcium and phosphate

levels to be followed to detect and avoid the development of malignant hypercalcemia.

Urinary N-telopeptides serve as an indicator for bone collagen breakdown, which parallels

tumor burden, and can provide a baseline to evaluate treatment progress.

Imaging

High quality, plain anteroposterior and lateral radiographs that show the involved

bone, including one joint proximally and distally, are the standard for initial assessment of

metastatic bone disease. One should look for lytic, blastic, or mixed lesions. Metastases from

lung, renal, and thyroid tumors tend to be entirely lytic (Fig. 2.1). Breast metastases may be

lytic or may show a mixed lytic–blastic appearance. The majority of prostate bone metastases

are blastic (Fig. 2.2) though lytic lesions do occur. Pelvic radiographs should include an

anteroposterior view and obturator and iliac oblique Judet views of the pelvis. A significant

amount of bone must be destroyed before a lesion will appear lytic on radiographs. Therefore,

a patient with a malignancy and bone pain often requires further evaluation despite normal-

appearing plain radiographs. Computed tomography (CT) is the study of choice when looking

for bone detail and cortical destruction, but is not as sensitive at assessing marrow

replacement. MRI on the other hand is very sensitive to early marrow replacement and can

locate metastases prior to their appearance on radiographs and CT, but is not as helpful for

bony anatomy. Total body radionuclide bone scan is useful in searching for other skeletal

sites of tumor involvement. It is a fairly sensitive technique for the detection of bone

metastases and can detect these lesions earlier than plain films; however, one disadvantage is

low specificity. Bone scans demonstrate areas of osteoblastic activity, and the radionuclide

accumulates at sites of fracture, infection, degenerative disease, bone metastases, and benign

tumors such as hemangioma and fibrous dysplasia. False-negative bone scans are often due to

destructive activity that exceeds reactive or blastic activity, as in multiple myeloma and in

tumors which are confined to the medullary cavity and do not affect the cortex.

Management Options

Medical/Radiation Therapy

Patients with cancer are often in a hypercoagulable state. Prophylaxis against deep

vein thrombosis (DVT) with pharmacologic agents and/or sequential compression devices

(SCD’s) is provided for patients who are non-ambulatory and at risk. Bisphosphonates inhibit

osteoclastic activity, suppressing bone resorption, and are commonly used to treat destructive

bony lesions from metastatic disease. One common bisphosphonate used in cancer patients is

pamidronate, which in conjunction with systemic chemotherapy, has been shown to decrease

or delay pathologic fractures due to bone metastases in breast cancer [4] and multiple

myeloma patients [5].

Zolendronate is also commonly used is many protocols. Chemotherapy and

radiotherapy should be used as indicated to stop or slow the neoplastic progression.

Postoperatively, chemotherapy and radiotherapy are often delayed between 7 and 14 days

after surgery in order to allow unimpeded would healing. Prostate, lymphoid, and breast

neoplasms are the most sensitive to radiation therapy. Lung and thyroid cancers are

intermediately responsive; gastrointestinal, melanoma, and renal tumors are typically

radiotherapy-resistant lesions. Treatment for metastatic lesions in the extremities can range

from a single 8 Gy dose to a 40 Gy dose divided over 15 daily fractions. Large single doses

are usually utilized for treating pain related to metastatic lesions, while smaller fractional

dosing allows a higher cumulative dose and is often used for definitive treatment or when

attempting to decrease the size of metastatic lesions. Metastatic bone lesions with a low

risk of fracture may be initially treated with radiation, which may negate the need for

subsequent surgical intervention.

Surgery

Indications

A pathologic fracture can be devastating in an elderly cancer patient and is a clear

indication for surgical intervention, with the patient’s medical condition and expected

survival playing a role in the decision to proceed to surgery. The treatment of metastatic bone

lesions in the absence of fracture is not so well-defined. Because pathologic fractures are

extremely detrimental, prophylactic surgical treatment of impending fractures has been

shown to improve outcomes [6]. In 1989, Mirels [7] developed a scoring system designed to

predict the risk of pathologic fracture due to bone metastases in the extremities.

The Mirels classification is based on the degree of pain, lesion size, lytic versus

blastic nature, and anatomic location as shown in Table 2.1. Mirels recommended

prophylactic fixation for a total score ³9. The variability in quality of surrounding bone,

behavior of metastases from different tumor types, response of these metastases to treatment

including radiation, and patient activity level can also have an effect on the probability of

fracture. While this scoring system is helpful, we feel that the most reliable predictor of

impending fracture is mechanical pain.

Mechanical pain is a physiologic indicator that the involved bone cannot withstand

the physical stresses placed upon it, and is therefore at risk of fracture. As a result, all

metastatic lesions in the extremities that exhibit mechanical pain should be considered for

prophylactic fixation. One important caveat to any surgeon considering operative intervention

for a suspected bone metastasis is to recognize the possibility of an unrelated primary bone

tumor in a patient with a previously diagnosed malignancy. As a general rule, the first time a

tumor presents with metastasis to bone, histological confirmation with a biopsy or intra-

operative frozen section should precede definitive surgical intervention. When the diagnosis

is confirmed, immediate internal fixation is reasonable.

If concern for a potential primary bone sarcoma persists, definitive surgery should be

postponed. Passing an intramedullary nail through a primary bone sarcoma will result in

distal seeding of the medullary canal and will frequently necessitate amputation.

Treatment Options

The goals of surgery for impending or pathologic fracture in the setting of metastatic

disease are to provide pain relief and a functionally stable and durable construct that will

allow the patient to ambulate shortly after surgery and will persist for the life of the patient.

This is quite a challenge in some cases given the large amount of bone loss, the degree of

osteoporosis in the elderly, and the decreased ability of bone to heal in the local setting of

tumor. Therefore, techniques used in patients with pathological fractures differ from those

used in young patients with traumatic fractures in which fixation is placed as a temporary

stabilizing measure while fracture healing occurs. The idea in the fixation of metastatic

pathologic fractures is to reinforce or replace the compromised bone with a rigid and durable

construct. This typically requires plates or intramedullary rods with the addition of

methylmethacrylate, or bone cement, to fill the bone defects. If the fracture is near a joint,

and stable and durable fixation cannot be achieved by the described methods, joint

arthroplasty may provide a more durable construct and may require less operative time and

blood loss. Occasionally, segmental replacement prostheses may be used (Fig. 2.3), which

not only replace the joint surface and nearby bone but also replace varying lengths of

diaphyseal bone with metal. These are typically used in malignant primary tumors of bone

where large segments of bone must be resected; although they may also play a role in

metastatic bone disease. Surgical alternatives, although not all-inclusive, for fixation or

reconstruction of impending or pathologic fractures in the extremities were proposed by

Lackman et al. [8] and are presented in Table 2.2.

Postoperative Care

The postoperative physical therapy largely depends on the type of construct used and

the intra-operative observations made by the surgeon regarding the quality of bone, screw

purchase, and overall stability of the construct. The goal is to achieve mobility and

independence in order to improve the quality of life and to decrease cardiopulmonary

complications that are associated with immobility in the elderly patient.

Adequate pain control is necessary for participation in physical therapy. DVT

prophylaxis is very important in cancer patients that are immobilized. Bisphosphonates,

radiation therapy, and chemotherapy should be used as indicated, keeping in mind that

radiation and chemotherapy decrease wound healing and may be delayed.

METASTATIC BONE DISEASE7

Incidence of Bone Metastases

Bone is the most common site for metastasis in cancer and is of particular clinical importance

in breast and prostate cancers because of the prevalence of these diseases. At postmortem

examination, f70% of patients dying of these cancers have evidence of metastatic bone

disease (Table 1;ref. 1). However, bone metastases may complicate a wide range of

malignancies, resulting in considerable morbidity and complex demands on health care

resources. Carcinomas of the thyroid, kidney, and bronchus also commonly give rise to bone

metastases, with an incidence at postmortem examination of 30% to 40%. However, tumors

of the gastrointestinal tract rarely (<10%) produce bone metastases.

Distribution of Bone Metastases

Bone metastases most commonly affect the axial skeleton. The axial skeleton contains the red

marrow in the adult, which suggests that properties of the circulation, cells, and extracellular

matrix within this region could assist in the formation of bone metastases. Evidence exists

that blood from some anatomic sites may drain directly into the axial skeleton. In postmortem

studies of animals and humans, Batson showed that venous blood from the breasts and pelvis

flowed not only into the venae cavae but also into a vertebral-venous plexus of vessels that

extended from the pelvis throughout the epidural and perivertebral veins.The drainage of

blood to the skeleton via the vertebral-venous plexus may, at least in part, explain the

tendency of breast and prostate cancers, as well as those arising in kidney, thyroid, and lung,

to produce metastases in the axial skeleton and limb girdles. Of course, the vertebral-venous

plexus does not provide the entire explanation of why these cancers metastasize to the

skeleton. Molecular and cellular biological characteristics of the tumor cells and the tissues to

which they metastasize are of paramount importance and influence the pattern of metastatic

spread.

Prognosis

In many patients, metastatic bone disease is a chronic condition with an increasing range of

specific treatments available to slow the progression of the underlying disease. The survival

from the time of diagnosis varies among different tumor types. The median survival time

from diagnosis of bone metastases from prostate cancer or breast cancer is measurable in

years. In contrast, the median survival time from the diagnosis of advanced lung cancer is

typically measured in months. The prognosis after the development of bone metastases in

breast cancer is considerably better than that after a recurrence in visceral sites. For example,

in a study by Coleman and Rubens of patients whose cancers were diagnosed in the 1970s

and 1980s and who were treated at a single institution, the median survival was 24 months in

those patients with first recurrence in the skeleton compared with 3 months after first relapse

in the liver (P < 0.00001). Coexisting nonosseous metastatic disease is important in

determining prognostic differences between patients with bone metastases from the same

type of tumor. Additionally, for patients with advanced breast cancer and metastatic disease

confined to the skeleton at first relapse, the probability of survival is influenced by the

subsequent development of metastases at extraosseous sites. In a study of 367 patients with

bone metastases from breast cancer, those who later developed extraosseous disease had a

median survival of 1.6 years compared with 2.1 years for those with disease that remained

clinically confined to the skeleton.

Clinical Features

Skeletal metastatic disease is the cause of considerable morbidity in patients with advanced

cancer. The frequency of skeletal complications (also known as skeletal-related events)

across a range of tumor types receiving standard systemic treatments but no bisphosphonates

is shown in Fig. 2. On average, a patient with metastatic disease will experience a skeletal-

related event every 3 to 6 months. However, the occurrence of these morbid events is not

regular, with eventsclustering around periods of progression and becoming more frequent as

the disease becomes more extensive and the treatment options reduce.

Pain. Bone metastases are the most common cause of cancer-related pain. The

pathophysiologic mechanisms of pain in patients with bone metastases are poorly understood

but probably include tumor-induced osteolysis, tumor production of growth factors and

cytokines, direct infiltration of nerves, stimulation of ion channels, and local tissue

production of endothelins and nerve growth factors. Although f80% of patients with

advanced breast cancer develop osteolytic bone metastases, approximately two thirds of such

sites are painless. Different sites of bone metastases are associated with distinct clinical pain

syndromes. Common sites of metastatic involvement associated with pain are the base of

skull (in association with cranial nerve palsies, neuralgias, and headache), vertebral

metastases (producing neck and back pain with or without neurologic complications

secondary to epidural extension), and pelvic and femoral lesions (producing pain in the back

and lower limbs, often associated with mechanical instability and incident pain).

Hypercalcemia. Hypercalcemia most often occurs in those patients with squamous cell lung

cancer, breast and kidney cancers, and certain hematologic malignancies (in particular

myeloma and lymphoma). In most cases, hypercalcemia is aresult of bone destruction, and

osteolytic metastases are present in 80% of cases. In breast cancer, an association exists

between hypercalcemia and the presence of liver metastases. This association may reflect a

relationship between liver involvement and production or reduced metabolism of humoral

factors with effects on bone such as parathyroid hormone–related peptide or receptor

activator of nuclear factor-nB ligand. Secretion of humoral and paracrine factors by tumor

cells stimulates osteoclast activity and proliferation, and there is a marked increase in markers

of bone turnover. Several studies have established the role of parathyroid hormone– related

peptide in most cases of malignant hypercalcemia. The levels of circulating parathyroid

hormone–related peptide are elevated in two thirds of patients with bone metastases and

hypercalcemia and in almost all patients with humoral hypercalcemia. The kidney also has a

role in malignant hypercalcemia;as a result of volume depletion and the action of parathyroid

hormone–related peptide, renal tubular reabsorption of calcium is increased, further

increasing serum calcium levels.

The signs and symptoms of hypercalcemia are nonspecific, and the clinician should have a

high index of suspicion. Common symptoms include fatigue, anorexia, and constipation. If

untreated, a progressive increase in serum calcium level results in deterioration of renal

function and mental status. Death ultimately results from renal failure and cardiac

arrhythmias.

Pathologic fractures. The destruction of bone by metastatic disease reduces its load-bearing

capabilities and results initially in microfractures, which cause pain. Subsequently, fractures

occur (most commonly in ribs and vertebrae). It is the fracture of a long bone or the epidural

extension of tumor into the spine that causes the most disability. As the development of a

longbone fracture has such detrimental effects on quality of life in patients with advanced

cancer, efforts have been made to predict sites of fracture and to preempt the occurrence of a

fracture by prophylactic surgery. Fractures are common through lytic lesions in weight-

bearing bones. Damage to both cortical and trabecular bone is structurally important. Several

radiological features have been identified that may predict imminent fracture;fracture is likely

if lesions are large, are predominantly lytic, and erode the cortex. A scoring system has been

proposed by Mirels based on the site, nature, size, and symptoms from a metastatic deposit.

Using this system, lesions that scored >7 generally require surgical intervention;deposits that

scored z10 had an estimated risk of fracture of >50%. More sophisticated predictive tools

based on computed tomography of sites at risk of fracture are currently under evaluation.

Compression of the spinal cord or cauda equina. Spinal cord compression is a medical

emergency, and suspected cases require urgent evaluation and treatment. Pain occurs in most

patients, is localized to the area overlying the tumor, and often worsens with activities that

increase intradural pressure (e.g., coughing, sneezing, or straining). The pain is usually worse

at night, which is the opposite pattern of pain from degenerative disease. There may also be

radicular pain radiating down a limb or around the chest or upper abdomen. Local pain

usually precedes radicular pain andmay predate the appearance of other neurologic signs by

weeks or months. Most patients with spinal cord compression will have weakness or

paralysis. Late sensory changes include numbness and anesthesia distal to the level of

involvement. Urinary retention, incontinence, and impotence are usually late manifestations

of cord compression. However, lesions at the level of the conus medullaris can present with

early autonomic dysfunction of the bladder, rectum, and genitalia.

In a retrospective analysis of 70 patients with spinal cord compression secondary to breast

cancer, the most frequent symptom was motor weakness (96%) followed by pain (94%),

sensory disturbance (79%), and sphincter disturbance (61%;ref. 27). Ninety-one percent of

patients had at least one symptom for >1 week;96% of those ambulant before therapy

maintained the ability to walk. In those unable to walk, 45% regained ambulation, with

radiotherapy and surgery equally effective. Median survival was 4 months.The most

important predictor of survival was the ability to walk after treatment. These results suggest

that earlier diagnosis and intervention may improve both outcome and survival.

Spinal instability. Back pain is a frequent symptom in patients with advanced cancer and in

10% of cases is due to spinal instability. The pain, which can be severe, is mechanical in

origin, and frequently the patient is only comfortable when lying still. Surgical stabilization is

often required to relieve the pain, and although such major surgery is associated with

considerable morbidity and mortality, excellent results can be obtained with appropriate

patient selection.

INITIAL EVALUATION8

The evaluation of a patient who definitely or potentially has a hip fracture involves reviewing

the patient's medical history, performing a physical examination, and carrying out

radiographic studies. The radiographic studies are used to determine the exact location

(Figure 1) and degree of displacement of the fracture; this information can help clinicians to

differentiate the various subtypes of proximal femoral fracture (e.g., intertrochanteric, femoral

neck, subtrochanteric, greater trochanteric).

The patient's symptoms and the physical examination findings usually depend on the type of

fracture and its degree of displacement. For most proximal femoral fractures, ecchymosis

generally appears during the first few days after the fractures occur. However, ecchymosis

may not develop with femoral neck fractures because the fracture hematoma may be

contained within the hip capsule.

Fractures of the proximal femur that are incomplete or nondisplaced may cause only minimal

pain with movement and weight bearing. However, clinical evidence of such fractures can be

obtained by using the Stinchfield test. With this test, the patient lies in a supine position and

attempts to lift the affected leg against gravity and then against weight resistance. If groin or

thigh pain is elicited during either of these exercises, the test is positive. Patients with

displaced fractures of the proximal femur usually cannot bear weight and report pain with

even slight movement of the affected extremity. The displaced fracture usually causes the leg

to shorten and become abducted and externally rotated to some degree. Furthermore, there

may be pain or crepitation with palpation of the lateral femur and trochanter.

Most fractures of the proximal femur can be observed on plain radiographs. Standard views

include an anteroposterior (AP) view of the pelvis and a true lateral view of the hip. With

respect to hard-to-see fractures, another view that may be helpful is an AP view obtained with

the hip internally rotated approximately 15 degrees. Magnetic resonance imaging (MRI) and

technetium bone scans may also prove useful. Although bone scans have a high sensitivity in

diagnosing fractures 48 to 72 hours after they occur, MRI has been found to be 100%

sensitive, can be used to identify fractures sooner, and is very useful for finding occult

fractures. Patients with acute hip pain and normal results on plain radiographs must be

assumed to have a hip fracture until proven otherwise; MRI or a technetium bone scan may be

needed to confirm the diagnosis of a symptomatic, nondisplaced fracture. If the hip joint is

irritable on physical examination, limited MRI is the best technique to confirm a fracture

within the first 2 to 3 days after it is thought to have occurred. If the patient's pain is more

diffuse, a technetium bone scan of the pelvis, lumbar spine, and hips may be preferred; a 3-

day interval between the injury and the performance of this test is necessary to allow

sufficient sensitivity. During this 3-day period, patients should practice protected weight

bearing and should receive treatment for pain.

GENERAL TREATMENT CONSIDERATIONS

The goal of treatment is to limit pain and to help the patient return to the level of activity he or

she had prior to sustaining the fracture. Efforts to attain this goal may or may not involve

surgery. Non-operative treatment is usually reserved for impacted or nondisplaced proximal

femoral fractures. The premise behind non-operative treatment is that if the patient can be

mobilized and his or her pain controlled, the risk of complications such as skin breakdown

and pulmonary illness is decreased. However, the risk of displacement of the fracture must

also be considered. In cases of femoral neck fractures, operative treatment is favored to avoid

displacement and possible avascular necrosis of the hip. For most proximal femoral fractures,

operative treatment is more appropriate.

Figure 1. Anatomic regions relating to areas of proximal femoral fractures.

Although hip fractures in young patients may be complicated by medical issues, surgical

treatment for these individuals is typically emergent. However, for elderly patients, who

sometimes have cardiac, pulmonary, and psychiatric co-morbidities, an immediate surgical

procedure may initially carry too high a risk for substantial morbidity and mortality. Prior to

surgery, elderly patients need to be medically evaluated to minimize any potential risks of

surgery. Medical work-up usually involves evaluating the patient for hypertension, heart

disease (including coronary artery disease, dysrhythmias, and congestive heart failure),

diabetes mellitus, chronic obstructive pulmonary disease, cerebral vascular disease, and

urinary tract infection.

The time needed to perform a complete medical evaluation and treat or manage co-

morbidities in elderly patients can delay surgery for at least 12 to 24 hours. Although there is

conflicting evidence about the mortality rate if surgery is delayed for 24 hours or less, there is

substantial evidence suggesting that if surgery is postponed for more than 3 days, the

mortality rate within the first year after this treatment doubles. It may be true, however, that

the patients who experience a delay of more than 3 days in undergoing their surgical

procedure are the most ill on presentation. Furthermore, prolonging the time before surgery

increases the risk of skin breakdown, urinary tract infection, deep vein thrombosis (DVT), and

pulmonary complications.

Moreover, if a patient, regardless of age, is receiving anticoagulation therapy because of atrial

fibrillation, valve replacement, history of transient ischemic attacks, or other reasons, reversal

of this therapy may be appropriate before the surgical procedure is performed. In general,

anticoagulation therapy can be reversed by administering fresh frozen plasma or vitamin K

(i.e., phytonadione). However, fresh frozen plasma is usually transient in its effect and can be

associated with transfusion reactions and other problems. Moreover, reversal of the

anticoagulative effect of warfarin with vitamin K can be complicated by thrombosis, and

doses of vitamin K greater than 10 mg can lead to warfarin resistance for as long as a week. If

a patient has been receiving warfarin, the prothrombin time and international normalized ratio

(INR) can be allowed to normalize by simply discontinuing the warfarin. In patients with a

history of transient ischemic attacks, cardiomyopathy, and atrial fibrillation, discontinuation

of warfarin is unlikely to lead to an adverse event. However, in patients with prosthetic heart

valves whose warfarin anticoagulation therapy is being reversed, unfractionated heparin

should be administered as the INR decreases to an acceptable level; the heparin can then be

discontinued hours prior to surgery.

Prior to surgery for hip fractures, most patients—irrespective of age—are confined to bed.

During this time, they most likely will require an analgesic agent, which can contribute to the

increased mental status changes seen in elderly patients. To help with the discomfort of a

displaced fracture, 5 lb of longitudinal (Buck's) skin traction can be used, although pillow

support alone has been shown to be just as effective. If surgery is delayed for a considerable

amount of time, DVT prophylaxis is indicated and can include graduated compression

stockings; sequential pneumatic calf, thigh, or ankle pumps; and low-molecular-weight

heparin.

INTERTROCHANTERIC FRACTURES

General Characteristics

Intertrochanteric fractures occur in the transitional bone between the femoral neck and the

femoral shaft (Figure 1). These fractures may involve both the greater and the lesser

trochanters. Transitional bone is composed of cortical and trabecular bone. These bone types

form the calcar femorale posteromedially, which provides the strength to distribute the

stresses of weight bearing. Consequently, the stability of intertrochanteric fractures depends

on the preservation of the postero-medial cortical buttress. Osteonecrosis is uncommon

because these fractures usually do not disturb the femoral head blood supply. Moreover,

because transitional bone is highly vascular, complications such as nonunions are uncommon

as well.

Classification

The most often used classification system for intertrochanteric fractures is based on the

stability of the fracture pattern and the ease in achieving a stable reduction. This classification

was introduced by Evans in 1949 and accurately differentiates stable fractures (standard

oblique fracture pattern) from unstable fractures (reverse oblique fracture pattern) (Figure 2).

It is important to identify a reverse oblique fracture because this type of fracture should not be

treated with a standard compression plate. The stability of intertrochanteric fractures depends

on the integrity of the posteromedial cortex, and instability increases with comminution of the

fracture, extension of the fracture into the sub-trochanteric region, and the presence of a

reverse oblique fracture pattern.

Figure 2. Simplified Evans' classification of intertrochanteric fractures: standard oblique

fracture (stable) and reverse oblique fracture (unstable).

Treatment

Surgery is the mainstay of treatment for both displaced and nondisplaced intertrochanteric

fractures. The primary reason for surgery is to allow the early mobilization of the patient, with

partial weight-bearing restrictions depending on the stability of the reduction. The most

common internal fixation device used today is the sliding screw-plate device (Figure 3). This

implant consists of a large lag screw placed in the center of the femoral neck and head and a

side plate along the lateral femur. The screw-plate interface angle is variable and depends on

the anatomy of the patient and the fracture. The advantage of the sliding lag screw, compared

with a static screw, is that it allows for impaction of the fragments; this impaction increases

the bone-on-bone contact, promoting osseous healing while decreasing implant stress. The

disadvantage is common shortening and rotation at the fracture site.

Although repair of an intertrochanteric fracture is often referred to as open reduction with

internal fixation (ORIF), the term closed reduction with internal fixation (CRIF) may be more

accurate. The patient rests in a supine position on a fracture table that allows the affected leg

to be placed in traction. The fracture is anatomically reduced by longitudinal traction and

rotation of the leg. An incision is made, and after the bone is exposed, the lag screw is placed

into the center of the femoral neck and head with fluoroscopic guidance. Optimally, the end of

the lag screw should be placed in close proximity to the apex of the femoral head so that the

sum of the distances between the end of the screw and the apex of the femoral head in the AP

and lateral views is less than 20 to 25 mm. By doing this, the occurrence of the complication

known as "cut out" of the lag screw from the femoral head can be almost completely

prevented. The next step is placement of the sliding side plate device, which is fixed to the

shaft of the femur by using cortical screws.

CRIF of intertrochanteric fractures may allow for immediate weight bearing. Depending on

the stability of the fracture and its fixation, touchdown weight bearing or partial weight

bearing is usually recommended for 4 to 6 weeks after the surgical procedure. When signs of

healing are apparent and fracture collapse has diminished, weight-bearing status is usually

increased. Long-term problems after these fractures are healed include malrotation, abductor

muscle biomechanical abnormalities, pain (owing to the hardware), and shortening of the leg

at the fracture site (because of collapse).

FEMORAL NECK FRACTURES

General Characteristics

Femoral neck fractures occur between the end of the articular surface of the femoral head and

the inter-trochanteric region (Figure 1). These fractures are intracapsular, and hip synovial

fluid may interfere with their healing. Healing may also be affected by disruption of the

arterial blood supply to the fracture site and the femoral head; with femoral neck fractures, the

lateral ascending cervical branches of the medial femoral circumflex artery are at risk for

disruption. Loss of this blood supply increases the risk of nonunion at the fracture site and the

risk for avascular necrosis of the femoral head.

Figure 4. Garden classification system of femoral neck fractures. (A) Garden I fracture:

incomplete and minimally displaced. The fracture shown is impacted and is in valgus

malalignment. (B) Garden II fracture: complete, nondisplaced. (C) Garden III fracture:

complete fracture and partially displaced. The fracture shown is in varus malalignment. (D)

Garden IV fracture: completely displaced, with no engagement of the 2 principal fragments.

Classification

The most commonly used classification system for femoral neck fractures is the Garden

system (Figure 4). The Garden system is based on the amount of displacement of the

fractures. Garden I fractures are minimally displaced and incomplete and are usually impacted

with the femoral head tilting in the posterolateral direction. Garden II fractures are complete

but nondisplaced. Garden III fractures are complete and partially displaced, and Garden IV

fractures are completely displaced. Although the Garden system is the most commonly used

system of classification, there is much inter-observer variability.

Treatment

Operative treatment is favored for femoral neck fractures. The specific type of operative

treatment depends on the age of the patient and the characteristics of the fracture (eg, location,

displacement, degree of comminution). In young patients, it is necessary to obtain reduction of

the femoral neck fracture as soon as possible to decrease the risk of avascular necrosis.

Anatomic reduction and subsequent fixation are the goals of surgery. Young patients usually

undergo closed or open reduction, with percutaneous placement of 3 parallel cannulated lag

screws (Figure 5). The procedure is performed with the patient in a supine position on a

fracture table. The parallel cannulated lag screws allow compression at the fracture site and

maintain reduction while the fracture heals. Elderly patients who have Garden I or II fractures

also benefit from parallel cannulated screw fixation, although this is usually performed in situ.

Hemiarthroplasty is the procedure of choice for elderly patients with displaced femoral neck

fractures. The previous activity level of the patient is important in determining the exact type

of hemiarthroplasty to perform. Independent ambulators benefit from a cemented

hemiarthroplasty, because pain after surgery and component loosening are minimal with this

approach. Hemiarthroplasty is most often performed with patients in the lateral decubitus

position. After the incision is made and the joint exposed, the femoral head is extracted and

the femoral neck is cut to allow placement of the prosthesis. There are many different

prosthetic devices, ranging from unipolar devices (including the Austin-Moore prosthesis) to

bipolar devices (Figure 6). The majority of these prostheses are cemented; however, in

elderly patients, who usually have compromised cardiopulmonary reserves, excessive

pressurization of the cement is avoided to prevent further metabolic and mechanical insult.3

Figure 5. (A) Radiograph (anteroposterior view) of a valgus, impacted (Garden I) femoral

neck fracture treated by way of internal fixation with 3 parallel cannulated lag screws. (B)

Schematic representation of screw configuration as viewed from the side.

Figure 6. Radiograph (anteroposterior view) of a displaced femoral neck fracture treated by

way of femoral head replacement with a bipolar prosthetic device.

Weight bearing after surgery for patients of all ages is dependent on the fracture type, patient

demands and compliance, and surgeon preference. In general, patients who have undergone

reduction and fixation with cannulated lag screws usually have a restricted weight-bearing

status after the procedure. In contrast, patients who have undergone hemiarthroplasty can be

allowed to bear weight as tolerated; certain restrictions of position are encouraged to prevent

dislocation.

SUBTROCHANTERIC FRACTURES

General Characteristics

Subtrochanteric fractures occur between the lesser trochanter and the isthmus of the diaphysis

of the femur (Figure 1). These fractures are less common than femoral neck and

intertrochanteric fractures.

Classification

Classification systems for subtrochanteric fractures have evolved in relation to the

development of new treatment devices. Early classification systems were based on the

location of the fracture and the number of fracture fragments. With the advent of special

intramedullary rods that can be used to treat these fractures, the Russell-Taylor classification

system was established.

The Russell-Taylor system is based on the lesser trochanter continuity and whether the

fracture extends posteriorly into the greater trochanter and involves the piriformis fossa

(Figure 7); this system comprises 2 types of fractures. These fracture types can be

differentiated on the basis of the appropriate use of the intramedullary nail. For type I

fractures, which do not extend into the piriformis fossa, closed intramedullary nailing has the

advantage of minimizing vascular compromise of the fragments. In contrast, type II fractures

involve the greater trochanter and the piriformis fossa, making use of closed intramedullary

nailing less favorable.

Figure 7. Russell-Taylor classification of subtrochanteric fractures. Type I fractures do not

extend into the piriformis fossa, and thus, intramedullary nailing can be beneficial. Type II

fractures extend proximally into the greater trochanter and involve the piriformis fossa; this

involvement complicates closed intramedullary nailing techniques.

Treatment

Treatment options for subtrochanteric fractures include nonoperative and operative methods.

However, as with intertrochanteric and femoral neck fractures, the mainstay of treatment is

surgery. The goal of treatment is fracture reduction so that near anatomic alignment and

normal femoral anteversion are obtained. One option involves use of an intramedullary nail

with interlocking hardware that extends into the femoral neck. Another option involves a

fixed angle extramedullary device, such as a 95-degree lag screw and side plate or blade plate

(Figure 8).

The screw and side plate and blade plate have been shown to have high rates of fracture union

when used with fractures involving the piriformis fossa, but intramedullary nails have been

recommended if the posteromedial cortical buttress cannot be established in unstable

fractures. It has also be suggested that the fixed angle extramedullary devices do not allow

compression at the fracture site; however, with the use of a plate tensioning device, this can

be overcome.

After fracture fixation, the patient usually requires protected weight bearing for 6 to 12 weeks,

and as callous formation is observed radiographically, weight bearing is slowly increased.

Operative treatment allows for immediate mobilization and pain management and decreases

the risk of complications such as skin breakdown, DVT, and pulmonary abnormalities.

Figure 8. Radiograph (anteroposterior view) of a sub-trochanteric fracture treated by way of

internal fixation with a blade plate.

GREATER TROCHANTERIC FRACTURES

General Characteristics

The greater trochanter is the insertion site of the gluteus medius and gluteus minimus (which

aid in hip abduction) and the insertion site of the piriformis, obturator internus, and gemelli

muscles (which aid in hip rotation) (Figure 1).

Classification

There are 2 common types of greater trochanteric fractures. The first and most common is

avulsion of the greater trochanteric apophysis of the femur, which occurs in skeletally

immature patients. This fracture usually occurs from a powerful muscle contraction of the

lateral hip rotators and is usually minimally displaced. The second type of greater trochanteric

fracture usually occurs in an elderly patient who has osteoporosis and results from direct

trauma, such as a fall.3 These fractures are most commonly minimally displaced, but the

portion of the bone attached to the piri-formis muscle can be markedly displaced.

Treatment

Both types of fracture can be treated conservatively with protected weight bearing on the

affected leg until the symptoms resolve. However, a nondisplaced greater trochanteric fracture

that results from a fall needs to be evaluated to confirm that the fracture does not extend into

the intertrochanteric region, which could result in displacement of the fracture. To evaluate

the fracture, limited MRI3 or a bone scan may be useful. If the trochanteric fracture involves a

large, completely displaced, and mechanically significant fragment of bone, it may require

reduction and fixation. Screws, cable devices, and tension band techniques have all been

advocated in such cases to reattach the insertion site of the hip abductors and hip rotators to

the proximal femur.

PROGNOSIS OF PROXIMAL FEMORAL FRACTURES

Most of the studies evaluating the prognosis of proximal fractures of the femur compare

intertrochanteric fractures with femoral neck fractures. In the surgical treatment of

intertrochanteric fractures, "cut out" of the implanted hardware is a preventable complication.

However, following surgery, loss of fixation of any type is less than 15% for both

intertrochanteric and femoral neck fractures. Other complications of surgical treatment of

proximal femoral fractures, such as nonunion and osteonecrosis, occur more often with

femoral neck fractures than with intertrochanteric fractures.

Complications that occur with hemiarthroplasty for femoral neck fractures include dislocation

of the prosthesis in addition to prosthesis loosening. The dislocation rate is related to

technique, but the overall incidence is low and can be decreased with strict hip-movement

precautions taught to the patient by the physical and occupational therapists.

Hospital stays tend to be longer for patients with intertrochanteric fractures, as opposed to

femoral neck fractures; likewise, a higher portion of patients with intertrochanteric fractures

require placement in a nursing home. Furthermore, although the overall 1-year mortality rate

is the same among patients with inter-trochanteric fractures and those with femoral neck

fractures, patients with intertrochanteric fractures have a slower recovery rate and a higher

mortality rate in the hospital at 2 months and at 6 months.

Elderly men are twice as likely to die soon after a hip fracture than are elderly women. In a

study of 804 community-dwelling patients, 31% of the men died within 1 year of sustaining a

hip fracture and 42% within 2 years. In comparison, only 15% of the women in the study died

within 1 year and 23% within 2 years.

PREVENTION OF HIP FRACTURES

Recovery from a hip fracture is complex and multidimensional: substantial losses in

contralateral hip bone mineral content, lean body mass, and performance and function are not

fully rectified in most cases. Therefore, prevention is important, especially for an aging

population. By 2020 the estimated number of proximal femoral fractures expected to occur in

the United States is 350,000 per year—and by 2040, between 530,000 and 840,000 fractures

are expected to occur.

Two preventive strategies to deal with this epidemic are the use of passive protective

garments and prevention and treatment of osteoporosis. Passive protection through the use of

hip pads has recently been demonstrated, and a gel pad with a rigid cover has been shown to

diminish the impact of falls. Current research is focusing on who should wear these garments

and the best way to increase patient comfort and compliance.

The prevention and treatment of osteoporosis may significantly decrease the risk for hip

fracture. It is particularly important to address this issue with respect to all elderly patients

being treated for their first hip fracture. The incidence of hip fractures is increased among

women older than 60 years who have sustained a hip fracture in the past. Bone mineral

density measured at the femoral neck by dual energy x-ray absorptiometry may be the best

predictor of hip fracture. Awareness of osteoporosis and a multifaceted team approach to

osteoporosis prevention and treatment are the best strategy to prevent fractures.