total hip & knee arthroplasty & rehabilitation implications: past, present, & future...

Total Hip & Knee Arthroplasty & Rehabilitation Implications: Past, Present, & Future

Celia Pechak, PT, MPH, PhDEast Texas District TPTA

April 26, 2008

Today’s Objectives• Review the evidence related to standard & minimally invasive

THA & TKA

• Encourage discussion related to participants’ clinical experiences with this patient population

• Offer practical resources for accessing the evidence & clinical expertise

• Stimulate participants’ interest in accessing & supporting clinical research in this area

Overview of Total Hip Arthroplasty (THA) & Total Knee Arthroplasty (TKA)

Currently 193,000+ THAs are performed per year in the US

Currently 381,000+ TKAs are performed per year in the US

750,000+ THA/TKAs per year are projected by 2030

Jones, Westby, et al., 2005

THA:Trip Down Memory Lane

1970s Admitted 1-2 days

before surgery Bedrest 2-3 days

post-op Partial weight

bearing LOS 17 days

Now Admitted morning of

surgery Mobilize day of

surgery or POD 1 Usually WBAT LOS < 5days

Ganz, 2004

And, the FUTURE… is it already here???........

Charnley THA

Sir John Charnley introduced the THA worldwide in 1960s

“…one of the most successful surgical interventions ever developed.”

25-year follow-up of 1689 patients (2000 arthroplasties) who had Charnley THA between 1969 and 1971:

• 461 patients still living• 77.5% free of reoperation• 80.9% free of revision or removal of the implant for any reason• 86.5% free of revision or removal for aseptic loosening

Berry et al., 2002Image: www.totaljoints.info/ Charnley_foto.jpg

Standard THA

Standard total hip arthroplasty • Incision > 10 cm

» Posterior lateral» Anterior lateral» Direct lateral» Transtrochanteric

Pros & Cons of Approaches

Posterolateral approach• Return to normal abductor strength and

ambulation is faster in the posterolateral• Higher rates of dislocation than other

approaches

Lateral & transtrochanteric approaches• Higher rates of post op limp due to gluteal

nerve injury or avulsion of gluteal flap Wenz et al., 2002

Optimal Approach?

Cochrane Systematic Review was done to determine optimal approach for adults with OA

Insufficient data to reach firm conclusion

Jolles & Bogoch, 2006

Complications DVT (8% to 70%) Leg length discrepancy Component malalignment Infection Improper implant fixation to surrounding

bone Nerve palsy Prosthetic hip dislocation

Otto, 2005

Revisions with Charnley THA

• Men had 2-fold higher rate of revision for aseptic loosening than women

• Patients with inflammatory arthritis were at lower risk of needing revision compared to patients with osteoarthritis

• Younger age at time of surgery, increased rate of acetabular > femoral component failure

Berry et al., 2002

Nerve Palsy

Prevalence rate of 0.17% in one review of 27,000 patients

Risk factors: hip dysplasia, posttraumatic arthritis, posterior approach,

lengthening > 1.1cm

70% of patients with incomplete palsy recovered fully

36% of patients with complete palsy recovered fully at a mean of 21 months

Huo et al., 2006

Cumulative Long-term Risk of Dislocation

Retrospective study 5459 patients s/p Charnley THA between 1969 and 1984

routinely followed until revision or death

4.8% dislocated

Highest risk in first year s/p surgery

Patients at highest risk:• females, those with dx of osteonecrosis of femoral head,

acute fx, or nonunion of proximal part of femur

Berry et al., 2004

Late Dislocation

15964 pts s/p THA between 1969 & 1995

32% of the dislocated hips first dislocated 5 or more years after primary THA

(median 11.3 yrs)

Late dislocations associated with:• long-standing problem with prosthesis, trauma, neurologic decline,

polyethylene wear, or combination

Image: www.wheelessonline.com/ image8/adihp1.jpg

Knoch et al., 2002

Are Hip Precautions Necessary?

499 patients s/p THA via anterolateral approach

No post-operative restrictions

3 dislocations within 6 weeks post-op (0.6%)

Stable hip achieved after closed reduction

Low early dislocation rate can be achieved using anterolateral approach without restrictions

Talbot et al., 2002

Treatment of Dislocation

Cochrane Systematic Review was completed to determine the best methods of treatment of recurrent dislocation following THA

No studies met their search criteria

Recommended multi-center study

Khan et al., 2006

Comparing Cemented vs. Cementless

Cemented technique:• 98% survivorship of implant at 10 years• 93% survivorship of implant at 25 years

Cementless technique:• Similar to above numbers for femoral

component, and better with acetabular component at 15 year mark

Cementless technique is now preferred method, especially in younger patients


Weight Bearing with Cementless THA

In the ole days: NWB &/or PWB Now: WBAT/FWB Rationale:

• NWB and TDWB produces greater joint pressure than FWB

• FWB does not adversely affect bone ingrowth or prosthetic stability

Jones, Westby et al., 2005

What Else Has Changed Since the Ole Days?

Trend towards less stiff & more biologically inert metal alloys

Greater use of modularity

Different bearing surface options

Experiments with bioactive ceramic coatings that increase bone ingrowth


Evolution in Bearing Surfaces

Metal-on-polyethylene• Problems with debris & osteolysis

Metal on cross-linked polyethylene• Greater wear resistance

Metal-on-metal• Low wear rates• Increasingly used in young, active patients

Ceramic on cross-linked polyethylene Ceramic on ceramic

• Low risk of ceramic bearing fracture


Impact of Analgesia Choice

• Compared 45 patients undergoing classic THA (3 groups of 15)

» IV patient-controlled analgesia with morphine» Continuous femoral nerve sheath block (FNB)» Continuous epidural analgesia

• All 3 provide similar pain relief & allow similar hip rehab

• FNB is associated with less side effects, so is recommended as first choice for analgesia

Singleyn et al., 2005

What is the Evidence Related to

THA & Rehabilitation?

Shift in Focus of Outcome Studies (THA & TKA)

Past research focused on surgical/technical aspects of surgery

Recent research uses more patient-centered outcomes

Outcome Measures in the Literature for THA

Harris Hip Score FIM

Oxford Hip ScoreWOMAC

SF-12HQ-12

Iowa Level of Assistance Scale12-Item Hip Questionnaire

Visual Analogue Scale

General Outcomes

Overall satisfaction with outcomes “good” to “excellent”

Patients s/p THA had SF-36 scores closer to the norm than patients s/p TKA

Predictors of overall satisfaction with THA: older age, not living alone, worse preoperative hip scale score, shorter LOS

Jones et al., 2005

What We Don’t Know

No randomized controlled trials have been done to determine the most effective rehab protocol

No prospective studies have determined the advantage of inpatient rehab post THA

No specific data on the type and duration of ROM restrictions

What We Are Not Sure About

Role of pre-op education• Inconsistent outcomes, but the studies have

generally reported decreased post-op pain, medication use, LOS, and fear/anxiety

Effect of pre-op exercise• Some evidence that pre-op exercise is of

benefit


What We Are Not So Sure About

It has not been determined if inpatient, outpatient, or home-based rehabilitation provides better long-term results and patient satisfaction

But more studies are appearing…


What We Do Know

Early transfer to inpatient rehabilitation is associated with faster achievement of goals

Very low hematocrit at inpatient rehabilitation admission is related to longer LOS & greater hospital charges, but did not impede overall gains in function (THA & TKA)

Munin et al. in Jones, Westby et al., 2005

Vincent & Vincent, 2007

What We Do Know Ongoing impairments and functional deficits for

as long as 2 years post THA

Of 67 patients treated with unilateral THA (original and revised) who presented for rehab with problems

6-9 weeks to one year post-op…

47% hip abductor weakness 28% muscle contracture 13% limb length difference 12% malalignment

> See article for treatment suggestionsBhave et al., 2005


Home Programs

Jan et al., 2004: • Patients s/p THA > 1.5 years in the past underwent a 12-

week home program that included hip flexion ROM, low resistance strengthening hip flex/ext/abd, and 30 min walking every day

• Exercise-high compliance group showed greater improvement in strength on operated side, fast walking speed, and functional score on Harris Hip Score than exercise-low compliance and control groups

• Recommend HEP 3x/week for training effect

Weight Bearing and Postural Stability Exercises

Trudelle-Jackson & Smith, 2004:• 34 subjects who had undergone THA 4-12 months

previously; 28 completed the study

• 8 week intervention: experimental group rec’d strength & postural stability exercises; control group rec’d basic isometric & AROM

• Exercise program emphasizing weight bearing & postural stability significantly improved muscle strength, postural stability & self-perceived function

**Study supported by the Texas Physical Therapy Foundation

Treadmill Training

Hesse et al., 2003: Treadmill training with Body-Weight Support is more effective than conventional PT at restoring symmetrical independent walking after hip replacement

White & Lifeso, 2005: Treadmill walking program may help persons with a THA achieve more symmetric gait

Biomechanical Considerations Related to Rehab

Hip exercises (such as SLRs) are more stressful to hip than walking

Functional activities including descending stairs, getting out of a chair, and bending/lifting with bent knees put the most stress on hips and knees


Issues Related to Sports & Recreational Activities During daily activities, loads of 3-4 X body weight

occur

5-10 X in sports activities to 25X with weight lifting

Increased speed of walking or running, increased loads

But slower than “normal walking speed” also increases joint forces

Kuster, 2002


Risk vs Benefit of Inactivity?

Strong evidence exists that total joint in INACTIVE person will show less wear than that in an active person

But, exercise will decrease fall risk, increase bone density & thus prosthesis fixation (amongst other benefits!!)

Kuster, 2002

Sports Activity Recommendations Recommendations on athletic activities after joint

replacement are based on opinions of orthopedic surgeons, not research

Consensus recommendations for patients s/p THA per 1999 Hip Society Survey

• Recommended/allowed – e.g., swimming, walking• Allowed with experience – e.g., canoeing, hiking,

XC skiing• Not recommended – e.g., high impact aerobics, jogging• No conclusion – e.g., speed walking, downhill skiing,

weight machines, ice skating

Kuster, 2002

When Can Patients Resume Sexual Relations After THA?

67% 254 surgeons surveyed recommended waiting 1 to 3 mos. following THA

30% would allow within first 4 weeks

5 safe positions for men and 3 for women were approved by 90% surgeons

Dahm et al., 2004

Exercise & Activity Recommendations

Patients should be advised to comply with their exercise programs for at least one year after surgery

Avoid sporting activities that create high compressive or rotary forces or increase risk of injury to the new joint


Minimally-invasive THA General definition: incision < 10 cm Strict definition: incisions that do not

involve cutting muscles or tendons

Single incision (1-MITHA)• Modification of old approach

» E.g., top half of post-lat or ant-lat approach

• May be less cutting of muscles/tendons, or not

Two incisions (2-MITHA)• New approach• Use intermuscular planes to access joint

2-MITHA

Anterior incision: over femoral neck; femoral head & neck removed; acetabular component placed

Posterior incision: in line with femoral canal; femoral component placed(Berry DJ et al., 2003 - http://ezproxy.twu.edu:2754/cgi/content/full/85/11/2235)

Enthusiasm vs. Skepticism

Potential for quicker recovery

Better cosmesis Less perceived invasion

of the body M-I procedures work

well for other surgeries Patients are asking for

MITHA

Potential for increased complications

• Smaller visual field• Learning curve

Difficult to perform studies without observer or selection bias

Are short-term benefits worth increased risk?

Why fix what isn’t broken? (classic THA is one of most successful operations invented)

Is it really minimally invasive?Berry, 2005

Is MITHA ReallyMinimally Invasive?

Mardones et al., 2005• 2-MITHA & posterior approach 1-MITHA

performed on 10 cadavers• Authors conclude that they cannot support 2-

MITHA can be done reliably without substantial damage to abductor muscles, external rotator muscles or both

• Abductor muscle damage also occurred in every 1-MITHA

Overview of 2-MITHAper Dr. Richard Berger

(surgeon-developer of 2-MITHA)

Best candidate: thin woman with atrophic changes

Need specialized instruments Fluoroscopy used during procedure Computerized navigation systems might

improve technique Limited to cementless application Surgery itself is more expensive, but shorter

hospital stay & rehabBerger, 2004

Berger: 2-MITHA

Berger et al., 2004• 100 patients received 2-MITHA with minimal

soft tissue trauma, capsule incised not excised• Initiated WBAT on day of surgery with no

post-op precautions• All patients independent with transfer,

ambulation w/ crutches, and stairs within 23 hours

• Mean age of 56 years old

Berger: 2-MITHA

• Mean of 6 days to discontinue crutch use, d/c narcotic pain meds, and start driving

• Mean of 8 days to return to work• Mean of 9 days to d/c any assistive

devices• Mean of 16 days to walk ½ mile• No readmissions, dislocations,

reoperations by 3 months follow-up

2-MITHA: on the other hand…

Pagnano et al., 2005• 80 patients treated with 2-MITHA, compared

with standard posterior approach done in past• Modest early functional outcomes

» 2.8 days in hospital vs. 5.2 in control» 90% d/c’d home vs. 65% in control

• But, there have been improvements in anesthesia and lifting of WB restrictions since ‘control’ group operated on, and so these might have contributed to better outcomes

2-MITHA: on the other hand…

Pagnano et al., 2005• 14% complication rate• 5% required reoperation• Older, obese women at risk in particular• Unpredictable technical challenges• Complications not just related to learning curve• Mean age of 70 years old

1-MITHA

Woolson et al., 2004• 50 patients with 1-MITHA compared with 85

patients with standard incision• No significant differences in average surgical

time, intraoperative blood loss, in-hospital transfusion rate, LOS, or disposition

• 1-MITHA had significantly increased risk of wound complication, acetabular component malposition, and poor fit/fill of femoral components

• No benefit except smaller scar

MITHA

Advances in practice are ahead of the evidence

Much more research is needed

One More Surgical Option

Hip resurfacing

(standard vs. mini-incision)

http://www.totaljoints.info/surface_hip_replace.htm

QUESTIONS

&

DISCUSSION

About THAs

Time for TKAs!

TKA: Another Trip Down Memory Lane

1970s Admitted 1-2 days

before surgery Bedrest 2-3 days post-

op Ambulation with knee

splint begun POD 3 Knee ROM begun POD 7 No discharge until knee

flex = 90

Now Admitted morning of

surgery Mobilize day of surgery

or POD 1 Usually WBAT LOS < 5days CPMs placed in post-op

Ganz, 2004

Cemented TKA

Cemented TKA is current gold-standard

10-14 year survival rate of 94-98%

Cobalt-chromium alloy femur articulating with standard polyethylene tibial surface is most common

Image: http://www.nlm.nih.gov/medlineplus/kneereplacement.html Jones, Westby et al., 2005

TKA Options

Not enough evidence to say whether keeping or removing PCL is best

Recent literature synthesis suggests that resurfacing the patella probably improves outcomes and pain-free function

Jacobs et al., 2007


Reducing Polyethylene Wear Use of cross-linked polyethylene decreases

wear – but long-term effectiveness has not been established

Use of rotating platform or mobile bearing knee implants are used to decrease contact stresses at implant interface

Mobile bearing knee implants provide about the same amount of ROM and pain relief as fixed bearing implants


Jacobs et al., 2001

What Is the Evidence Related to TKA & Rehabilitation?

Outcome Measures in TKA Literature

FIM Lower Extremity Functional Scale Six-Minute Walk Test SF-36 WOMAC Knee Society Clinical Rating System

Patient Satisfaction & Pain

15 year follow-up study of 4606 primary TKAs

Men, patients with OA, and those requiring revision indicated least satisfaction

Older patients, females, and patients without revisions reported the least pain

Roberts et al., 2007

What We Don’t Know

No randomized controlled trials have been done to determine the most effective rehabilitation protocol

No studies have prospectively assessed benefit of inpatient rehab post-TKA


What We Are Not Sure About

Role of pre-op education• Inconsistent outcomes, but the studies have

generally reported decreased post-op pain, medication use, LOS, and fear/anxiety

Pre-op exercise• Inconclusive studies• Improvement with pre-op function but not in

post-op recovery, decrease of LOS or complications


What We Are Not So Sure About

It has not been determined if inpatient, outpatient, or home-based rehabilitation provides better long-term results and patient satisfaction

But more studies are appearing…


What We Do Know

Significant long-term impairments and disability (including pain) can continue for one year or more post-TKA


Functional Activities

Systematic Review

Exercises based on functional activities may be more effective than traditional exercise programs (ROM & isometrics)

Any benefits seen after treatment did not persist to one year follow up

Lowe et al., 2007

Rehab Progress Post TKA Repeated measurements taken over one year period

of patients post TKA who had received short-term inpatient rehab, HEP, and some had additional rehab in community

Greatest improvements found in first 12 weeks post-TKA

Slower improvement 12-26 weeks

Little improvement post 26 weeks

Kennedy et al., 2008

Continuous Passive Motion Cochrane Systematic Review

CPM + PT significantly increased active knee flexion, decreased length of stay, and decreased the need for post-op manipulation (compared to PT alone)

CPM may improve short-term rehabilitation

But CPM does not appear to offer long-term advantage

Milne et al., 2007


Obesity & TKA

Review of recent literature

Conflicting evidence as to whether obese patients have lower functional gains and higher complication rates

Thompson et al., 2008

Extensor Mechanism Disruption

290 patients post TKA

6 had extensor mechanism disruption

This group had overall worse functional outcomes, requiring intensive rehab

Schoderbek et al., 2006

Bilateral TKAs

Compared 12 patients with unilateral TKA to gender/age/BMI-matched patients with bilateral TKAs

Short-term and long-term outcomes were equal by 12 weeks, except quad strength

Quad strength was equal by 52 weeks

Patterson & Snyder-Mackler, 2006

Sports & Activity Recommendations

Knee Society recommendations: Suitable: cycling, swimming, low-resistance

rowing, walking, hiking, low-resistance weight-lifting, ballroom dancing, square dancing

Suitable but more risky: downhill skiiing, ice-skating, speed walking, hunting, low-impact aerobics, volleyball

Avoid: Baseball, basketball, football, hockey, soccer, high-impact aerobics, jogging, parachuting, power-lifting

http://www.kneesociety.org/index.asp/fuseaction/site.totalKnee

Minimally Invasive TKA

Shorter incision Quadriceps sparing

http://www.orthop.washington.edu/uw/tabID__3376/ItemID__25/mid__10357/wversion__Staging/index__False/DesktopModules/Pictures/PictureView.aspx

Minimally Invasive TKA

Early, limited results:• Better ROM• Less blood loss• Shorter LOS

No long-term studies yet


Image: http://www.orthop.washington.edu/uw/tabID__3376/print__full/ItemID__68/mid__0/Articles/Default.aspx

Minimally Invasive TKA First 100 MITKAs were compared to previous 50

standard TKAs by one high volume surgeon

Longer operative time, less accuracy, more patellar tilt in first 25 MITKAs

Overall, shorter LOS, less need for inpatient rehab, less narcotic usage, and less need for assistive devices at 2 weeks post-op

Conclusion: Learning curve may be too long for low-volume surgeon

King et al., 2007

Unicompartmental Arthroplasty

“Partial” knee replacement Usually done with minimally

invasive technique

Image: http://www.orthop.washington.edu/uw/minimallyinvasive/tabID__3376/ItemID__7/PageID__3/Articles/Default.aspx

Unicompartmental Arthroplasty

More rapid recovery Minimal bone loss Less pain Shorter LOS 10-15 year survival rates range from

95-98%


QUESTIONS

&

DISCUSSION

About TKAs

Conclusion - Key Points

Surgical techniques and subsequent rehabilitation of THA & TKA patients continue to evolve

All minimally-invasive arthroplasties are not equal

Still much controversy amongst orthopedic surgeons as to whether benefits outweigh costs & risks of minimally invasive arthroplasties

More research related to THAs/TKAs rehabilitation is needed!

Resources for Evidence-Based Practice & Best Practices

Open Door:• Easy access to the literature• Find it in the “Research” section of www.apta.org

APTA Listservs– Geriatrics Section– Acute Care Section >> Quick and easy access to faculty & clinicians

who can help answer your questions

RESEARCH

Always use it!

Maybe do it?

Please support it!

Texas Physical Therapy Foundation

Foundation for Physical Therapy

THANK YOU!

total hip & knee arthroplasty & rehabilitation implications: past, present, & future...

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