osteo-arthritis knee, strategies for management

Operative Strategies for Management of Knee Osteoarthritis

Dr. A.K.VenkatchalamMJRC Clinic, Chennai

Goals of Osteoarthritis TreatmentThe treatment is directed at symptoms and slowing progress of

the condition

R elieve pain

R estore function

R educe disability

R ehabilitation

Goals: 4 R’s

Surgery

Indications• Pain refractory to conservative measures• Functional disability of the patient to carry out routine day to

day activities• Loose bodies or osteochondral fractures• Deformity usually genu varum • Progressive limitation of knee motion

Surgery

Surgical Methods

Arthrodesis(rarely used)

Total Knee Arthroplasty

Unicondylar Knee Arthroplasty

High Tibial Osteotomy

• Considered in treatment for uni-compartmental osteoarthritis of knee usually with concomitant varus or valgus deformity

• Biomechanics of osteotomy is; unloading of involved joint compartment by correcting malalignment and redistribution of the stress uniformly on the knee joint


High Tibial OsteotomyIndications

Classic: Age <60 yearVarus <15°

ContraindicationsAbsolute:

Diffuse osteoarthritis > Grade 2 changes in PF joint Tibiofemoral subluxation Inflammatory arthritis Menisectomy in the

compartment Unrealistic expectation

Relative: Age >65 years Obese (>1.32 x ideal

bodyweight) Poor ROM <90° Non-specific knee pain

Guiding Principles• Static and dynamic angle measurement• Ligamentous laxity• Antero-posterior instability• Patient factors


Four basic types1. Lateral closing wedge osteotomy2. Medial opening wedge osteotomy3. Dome osteotomy4. Medial opening hemicallotaxis


Lateral Closing Wedge Osteotomy

• Described by Coventry et al.• Measure the amount of correction needed to achieve

normal angle then additional 3 to 5 degree of overcorrection is added.

• Calculation of existing and desired mechanical axes by weight bearing full length x rays.

• Calculating the size of wedge removed as roughly 1 degree of correction for 1 mm length at the base of the wedge (if the width of the tibial plateau is 57 mm).

If tibia is 57 mm wide, width of wedge=degrees of correctionOR

Length = Diameter of tibia x 0.02 x Angle


Types of Closing Wedge Osteotomy

Above tibial tubercle Large cancellous

surface Close to deformity Time honored Minimal learning

curve Smaller incision

Behind tibial tubercle Stable fixation No step off Can displace tibial

tubercle anteriorly- Macquet effect on patellofemoral arthritis

No patellar tendon scarring

Below tibial tubercle• Large proximal

fragment• Allows correction in

multiple planes• No bone removed• Minimal incision• No retropatellar

scarring• Normal Q-angle

Incision Positioning transverse osteotomy guide


Placement of oblique osteotomy guide & performing osteotomy

Application of compression clamp & L- plate


Completion of osteotomy requires disruption of proximal tibio fibular joint or removal of infero medial portion of fibular head

After osteotomy fragment are fixed with plate and screws

Passive ROM started immediately after surgery Partial weight bearing on 2nd day Full weight bearing after 6 weeks


Described by Hernigou Preferred method by most

surgeons nowadays. Synthetic bone substitute may or

may not be used depending on the plate design.

Tricortical illiac crest bone graft with supplemental cancellous bone graft can be used

Indicated when involved extremity is 2cm or more shorter and/or when there is an associated medial collateral ligament laxity

Medial Opening Wedge Osteotomy


A tourniquet is used The skin incision is placed vertically, on the medial side of the tibia curve

to the proximal and dorsal side. The periosteum is then cut and partially stripped K-wire is drilled under direct fluoroscopic control in an oblique manner

and at an angle to the tibial axis aiming for the upper part of the fibular head. Cut is made only upto a pre determined point on the lateral tibial plateau based on pre op calculations.

When satisfactorily placed, the osteotomy is performed using an oscillating saw for the first part and finished using a chisel under fluoroscopic control.

Great care is taken not to damage the lateral cortex The tibia is manually wedged to the point of desired

correction, and the osteotomy plate positioned and fixed

The osteotomy gap may or may not be filled with synthetic bone substitute/ tricortical illiac crest bone graft with supplemental cancellous bone graft

A drain is then placed subcutaneously and the wound closed



Time honored Commonly available

jig Higher union rate Fixation covered with

soft tissue Decreases tibial slope


Easy exposure No fibular osteotomy

required Options of fixation wide May increase MCL

tension Restores bone stock

Advantages of Closing Vs Opening Wedge Osteotomies

Described by Maquet Determine the angle of correction Midline vertical incision Curved line is marked on bone with its dome just above

tibial tuberosity Multiple small drill holes made over this line

Dome Osteotomy

Dome Osteotomy

Two K-wires inserted parallel to each other on either side of osteotomy

Complete the osteotomy using osteotome Distal fragment is rotated untill desired angle subtend

by wire Fix the osteotomy using staples or plate.

Dome Osteotomy

Described by Turi Medial opening wedge osteotomy with application of

dynamic external fixator At 7th postoperative day, the fixator is distracted 0.25 mm

four times a day until desired correction is obtained It is a slow distraction at the osteotomy site and hence

obviates the need of bone grafting

Opening Wedge Hemicallotasis

Position the fixator over the leg to check the position of the pin clamps, osteotomy site and hinge

Osteotomy site is below the tibial tuberosity

Make longitudinal incision just medial to tibial tuberosity up to 3-4 cm

Position of the fixator over the lateral tibial cortex at the level of osteotomy


Fixator secured with K-wires Proximal fixator pin inserted


Medial and lateralproximal fixator pins

Distal fixator pin placed


Osteotomy guide attached Series of holes drilled at osteotomy site


Holes connected with osteotome

Distraction of osteotomy


Passive motion is started immediately after surgery Ambulation is begun on 2nd day, allowing weight bearing

to tolerance with crutches Seventh day after surgery, instruct the patient to

distract the fixator 1 mm/day After appropriate correction is achieved, fixator is

locked The fixator is removed after solid union is achieved


Complications of High Tibial Osteotomy

Recurrence of deformity Peroneal nerve palsy ( lateral closing wedge) Knee stiffness Patella baja Intra-articular fracture Non union Infection Osteo-necrosis of proximal fragment

Distal Femoral Osteotomy Indicated in active patients younger than 65

years with valgus angulation <15 degree Indicated when distal femoral malunion

which leads to unicompartmental arthritic changes.

Medial opening wedge or lateral closing wedge.

Determine the size of wedge to be removed Establish the angle of plate insertion Osteotomy done and is fixed by plate and

screws.

Knee Arthroplasty after HTO

Ideal HTO for TKR: Opening wedge osteotomy above the tibial

tubercle and a lax medial collateral ligament (MCL). Obviates the problems:

Patella infera Scarred patellofemoral ligament

Lifts the medial tibial condyle Tightens MCL. Restores almost normal alignment in relation to tibial

shaft.

Knee Arthroplasty Uni-compartmental (Uni-condylar) knee arthroplasty Total knee arthroplasty

Unicondylar Knee ArthroplastyIndications Classically: uni-compartmental osteoarthritis of the knee in a low-

demand, elderly, thin patient (> 60 years) with competence of both the cruciate and collateral ligaments

Currently accepted patient selection criteria Patients >60 years <82 kg weight Low level of activity Minimal rest pain. ROM - minimum arc of 90°

Flexion contracture <5°

Passively correctible angular deformity ≤ 10° varus or 15°valgus Patello femoral change < Grade 2. Uninvolved lateral compartment

Joint Preserving ACL & PCL, lateral meniscus retained Minimal bone resection: 2-4 mm resected No overcorrection – load sharing


MIS UKA


Erect

Postop xrays


Post op after Uni knee

• Mobilized full weight bearing on same or next day.

• Range of movement exercises commenced • Patient is discharged in one or two days.

Benefits1. Short hospital stay 2. Full range of motion 3. Speedy recovery and ability to walk unaided 4. Sit cross-legged on the floor 5. Reciprocal stair-climbing, brisk walking, jogging, golf6. Joint preserving minimally-invasive operation 7. Documented 10 year success >90% 8. Future surgery facilitated, not compromised 9. Functional results are optimum and recovery speedy 10. Cosmetically acceptable for isolated medial OA


Candidate for TKR Tri compartmental arthritis. Quality of life severely affected. Pain severely affecting the activities of daily living. Evidence of significant radiographic changes of the knee.


Total Knee ArthroplastyTKR consists of following: Cobalt chrome alloy or alternate

femoral component Cobalt chrome alloy or titanium

tibial tray UHMWPE tibial bearing

component UHMWPE patella component CR or PS design depending on

the disease and intra op findings. Both give satisfactory results.

The Incision Midline or medial skin incision is

with the knee in flexion. Sub fascial space is exposed Para patellar, mid vastus or sub

vastus approaches on deeper plane.

The joint is then exposed by raising a medial fascio periosteal flap.

Deep dissection upto or beyond the MCL depending on the deformity.


The leg is then extended and patella is everted The knee is once again flexed and the anterior horn of

medial and lateral menisci and anterior cruciate ligament are removed.

Posterior horns of menisci are excised after the femoral and tibial cuts are made.

Tibia is subluxated and rotated externally. The lateral tibial plateau is exposed by partial excision of

infra patellar fat pad.


The medial/lateral, antero- posterior screws of the ankle clamp are fine tuned to align the proximal tibial resection guide perpendicular to the proximal tibia in the coronal and parallel to the fibula in the sagital plane. Tibial slope is provided as needed.

To check alignment to the ankle, an alignment rod is used.


Bony cuts are made at first in order chosen by surgeon The amount of tibial resection depends on which side of

the joint is used for reference If unaffected side is taken as a reference, usually 9-10 mm

cut is taken which corresponds to the size of the implant If affected side is taken as a reference, the amount of

resection usually is 2 mm or less Proximal tibial cut is taken perpendicular to its mechanical

axis


A drill bit is used to create an opening in the femoral canal.

The valgus alignment guide is then used and attached to the IM reamer. It then rests and is secured on the distal femoral condyle.

A distal femoral cut at 5 to 7 degree of valgus is made.


The extension gap is first measured. An extension spacer corresponding to the minimal insert should be introduced comfortably. When extension space is achieved then proceed to AP and chamfer cuts.

The anterior and posterior femoral cuts determine the rotation of the femoral component and shape of the flexion gap.

A cut in 3 degrees of external rotation is made. More for valgus knees

Then flexion gap is measured. Box cut is taken to accommodate post cam mechanism of PCL

substituting design.


The flexion and extension gaps must be equal. Gap balancing is done by soft tissue releases and/or bony cuts.

If the extension gap is smaller then remove more bone from distal femoral cut surface after posterior soft tissue release and osteophyte removal.

If the flexion gap is smaller then remove more bone from posterior femoral condyles.

If the flexion and extension gaps are equal, but not enough space for prosthesis, remove more bone from proximal tibia.

Medial and lateral spaces are also checked for equality. Soft tissue releases/ tightening may be used to achieve symmetry.

When flexion and extension gaps are equal and balanced, chamfer cuts can be done.


Patellar resurfacing may be done on basis of intra op finding

First the patella is laterally retracted with the articular surface facing in the upward position.

Calipers are then used to determine the thicknes of the patella and the amount of bone that will be removed is calculated to leave at least 12 mm of patella behind.

The patella cutting guide is then placed ensuring the proper depth of cut.

Just sufficient bone is removed from the back side of the patella from below. Irrigation is used constantly during all bony cuts.

The patellar peg holding guide is then placed on the resected patella and the peg holes are then drilled.


With the knee flexed, appropriate femoral trials are placed on the distal femur and proximal tibia.

Appropriate spacer block is placed. Patellar insert is placed. Alignment is checked with reference to TA tendon and 2nd

toe distally and to the centre of the hip joint proximally. Medio lateral stability is checked in extension, 30⁰, 60⁰ & 90

⁰ flexion. In case of CR knee, POLO ( Pull out and Lift off tests are performed at 90 ⁰.

The knee is then put through a range of motions to confirm full extension and range of flexion.

Patellar tracking is checked at 90 ⁰ flexion and one towel clip at top of patella.

If everything is OK, trial components are removed after correct fit is confirmed.

The joint is then irrigated with a pulse lavage. Real components are cemented in.


Total Knee Arthroplasty The femoral impactor is used to insert the

femoral implant. The tibial base impactor is used to insert the

metal tibial base. The patellar implant is secured with bone

cement and held in place using the patellar hoding clamp.

The tibial polyethylene insert is seated and locked into place on the metal tibial base.

The cement is hardened with the leg placed in full extension.

Excess cement is removed


The wound is thoroughly irrigated. Tourniquet is release and bleeding is

arrested. Closed-suction drainage according to

surgeon’s preference. The wound is closed in layers and a

compressive dressing is applied. Static quads and ankle pumps are

commenced in the post op period as soon as the anesthetic has worn off.

Patient is mobilized full weight bearing on the same or next day.

Complications of TKA Thromboembolism Infection Patello-femoral complications Neurovascular complications Periprosthetic fractures


Arthrodesis

Indications• Severe disability in young & active

patient whose activity level might be detrimental to the longevity of a TKR.

• Infected TKR • Absent extensor mechanism• Hemophiliac knee• Failed revision • Neuropathic joint

Post infectious knee with deficient Extensor apparatus

Techniques of arthrodesis

Techniques of Arthrodesis External Fixation Intramedullary Nailing Plate Fixation

Dr.A.K.Venkatachalam is a fellow of the Royal college of surgeons of Glasgow and Post graduate of the prestigious University of liverpool.

His journey in Orthopaedics began in 1984 and continues He has received training in Joint replacements, arthroscopy and regenerative medicine .

He has been responsible for ushering in innovations in Joint replacements and regenerative medicine.

Get in touch- E mail- [email protected]

Dr.A.K.VenkatachalamMBBS, MS Orth, DNB OrthFRCS, M.Ch OrthConsultant in Orthopaedic surgeryChennai Meenakshi multi specialty hospital

osteo-arthritis knee, strategies for management

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