In the orthopaedic management of end-stage knee OA, the patient demonstrates a varus deformity of 15°, moderate bone loss on the medial tibial plateau, and preserved PCL. Which type of TKR implant most appropriately restores kinematics?

• A Posterior-stabilized (PS) total knee arthroplasty ✓
• B Unicompartmental knee arthroplasty (UKA)
• C Cruciate-retaining (CR) total knee arthroplasty
• D Hinged (constrained) total knee arthroplasty

Explanation

Posterior-stabilized (PS) TKR is preferred when significant varus deformity (>10–15°) requires medial soft tissue release that may compromise PCL function, or when bone loss on the medial plateau creates unequal flexion-extension gaps requiring the post-cam mechanism to substitute for the PCL. Cruciate-retaining TKR requires an intact, functional PCL. UKA is contraindicated with >10° varus fixed deformity and bone loss beyond one compartment. Hinged implants are reserved for significant instability, poor bone stock, or revision scenarios.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.