Dr Shams ur Rehman WazirPG Trainee Orthopedics B Unit

Hayatabad Medical ComplexPeshawar, Pakistan

drshamswazir@yahoo.com

overview

Anatomy of the knee jointCommon conditions leading to TKREvolution of TKRTotal knee replacementOur own data

Anatomy Of The Knee JointThree bones and three compartment

Knee StabilizersMidial Lateral Anterior Posterior Rotatory

Common Conditions That Lead To TKROSTEOARTHRITIS

Primary (idiopathic)Secondary

Post traumatic arthritisRHEUMATOID ARTHRITIS

Knee Arthritis

Far more common than hip OA in asian population

Age: 80% above 75 years

Sex: Equal in both sexes upto 45-55 years After 55 years more common in

female

Risk Factors Of Osteoarthritis

Increasing ageObesityFemale sexTraumaInfectionRepetitive occupational trauma

Clinical Features Of OsteoarthritisDepends upon stage of involvement

I. PainII. Loss of functionIII. StiffnessIV. SwellingV. DeformityVI. Crepitus

Radiological Features

Non Operative Treatment Non pharmacologic therapy

Patient’s educationUse of assistive devicesWeight lossPhysical therapyOccupational therapy

Pharmacologic therapyNSAIDSGlucosamine sulphateIntra articular CorticoteroidsIntra articular Hyaluronic acid

Operative Treatment

Arthroscopy OsteotomyKnee replacement surgery

Arthroscopic Debridement

Osteotomy

Knee ReplacementPartial knee replacementTotal knee replacement

Evolution of TKR

Fergussen(1860) resection arthroplasty Verneuil performed first interposition

arthroplasty 1940s- first artificial implants were tried

when molds were fitted in the femoral condyle

1950s- combined femoral and tibial articular surface replacement appeared as simple hinges

Evolution of TKR (cont)

Frank Gunston(1971), developed a metal on plastic knee replacement.

John Insall(1973), designed what has become the prototype for current total knee replacements. This was a prosthesis made of three components which would resurface all three surfaces of the knee - the femur, tibia and patella

Classification of Implants Design

Unconstrained Cruciate retainingCruciate substitutingMobile bearing knees

Constrained (Hinged)

Un constrained TKR

Constrained TKR

Uni condylar TKR

Total Knee Replacement TodayLarge variety is availableMajority of TKR today are condylar

replacements which consist of the followingCobalt-chrome alloy femoral componentCobalt-chrome alloy or titanium tibial trayUHMWPE tibial bearing componentUHMWPE patella component

Who Is A Candidate For TKR

Quality of life severely affectedDaily painRestriction of ordinary activitiesEvidence of significant radiographic changes

of the knee

What Is The Time For ReplacementOld age with more sedentary life styleYoung patients who have limited functionProgressive deformityOther treatment modalities have failedTKR should be done before things get out of

hand and the patient experiences a severe decrease in ROM, deformity, contracture, joint instability or muscle atrophy

Evaluation Of Patient Before SurgeryEvaluation Of Patient Before Surgery

A Complete Medical HistoryThorough Physical ExaminationLaboratory Work-up Anesthesia Assessment

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Recommended Preoperative Radiographs in Knee Replacement Surgery

1. Standing full-length anteroposterior radiographfrom hip to ankle

1. Lateral knee x ray 2. Merchant’s view

Goal of TKR

Pain reliefRestoration of normal limb alignmentRestoration of a functional range of motion

Successful Results Depends upon:

Precise surgical techniqueSound implant designAppropriate materialPatient compliance with rehabilitation

Technical Goals Of Knee Replacement Surgery

1. The restoration of mechanical alignment, 2. Preservation (or restoration) of the joint

line,3. Balanced Ligaments4. Maintaining or restoring a normal Q angle.

Mechanical AlignmentTKA aims at restoring the mechanical axis of the lower limb by:

Sequential soft tissue releasesCorrection of bone defects by grafts or prosthetic augments

4. Ligament Balancinga. Coronal Plane

For varus deformities’For valgus deformities

b. Sagittal PlaneFlexion contracturesExtension contractures

Procedure

Procedure

Procedure

Procedure

Procedure

Procedure

Procedure

Post Operative RehabilitationRapid post-operative mobilizationRange of motion exercises startedCPMPassive extension by placing pillow under

footFlexion- by dangling the legs over the side of

bedMuscle strengthening exercisesWeight bearing is allowed on first post op day

Prosthesis Survival

Different studies shows different resultsRanawat et al (Clin Orthop Relat Res )

95% at 15 years 91% at 21 yearsGill and Joshi (Am J Knee Surg) 96% at 15

years 82% at 23 yearsFont-Rodriguez (Clin Orthop Relat Res )

98% at 14 years

Ward DataTotal no of TKR done in last one year: 8

casesGender: Male ……. 5 cases Female….. 3 casesAge range: 40…….65 years Cause for which TKR done: OsteoarthritisBilateral/Unilateral: Single case for which

bilateral knee replacement was done.

Case 1

Case 1

Case 2

Case 3

Case 5