In total knee replacement, the posterior cruciate ligament (PCL) is either retained (CR-TKR) or sacrificed (PS-TKR). In which clinical scenario is PCL-retaining TKR relatively contraindicated?

• A Rheumatoid arthritis with PCL attenuation, significant flexion contracture >15°, or prior patellectomy ✓
• B Medial compartment OA with varus deformity <10°
• C Bilateral knee OA requiring staged surgery
• D Young active patients desiring high-flexion activities

Explanation

PCL-retaining TKR depends on an intact, functional PCL to provide femoral rollback on the tibial plateau. In rheumatoid arthritis, the PCL is frequently attenuated or deficient by synovial erosion; significant flexion contracture >15° requires additional posterior soft-tissue release that sacrifices PCL function; prior patellectomy alters the extensor mechanism mechanics making the posterior-stabilised cam-post mechanism more biomechanically appropriate. In these scenarios, posterior-stabilised (PS) designs with a tibial post replacing PCL function are preferred to avoid instability.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.