Intraoperative Discovery of Incorrect Femoral Component Packaging during Bilateral Total Knee Arthroplasty: A Near-Miss Case Report.

Abstract

Introduction: Incorrect implant delivery during total knee arthroplasty (TKA) is rare but represents a potential patient safety risk. Implant discrepancies may remain undetected until intraoperative opening despite correct external labeling.

Case report: A 76-year-old woman with bilateral varus knee osteoarthritis underwent simultaneous bilateral TKA using a medial pivot system planned with computed tomography-based patient-specific instrumentation. Cementless fixation was intended for both knees. The left knee was implanted uneventfully. During right TKA, a femoral component with correct external labeling was opened; however, the implant inside was a cemented component, one size larger than planned, and intended for the contralateral side. An appropriately sized backup component was available, allowing completion of surgery without interruption. At 1 year, range of motion improved from -5°-110° to 0°-120° on the left and from -10°-114° to 0°-125° on the right. Pain on the visual analog scale improved from 67 to 0, and the Western Ontario and McMaster Universities Osteoarthritis Index score improved from 56.1 to 90.6.

Conclusion: This intraoperative implant packaging discrepancy represents a near-miss event. Even with correct external labeling and meticulous pre-operative planning, implant mismatch may occur. Intraoperative verification and immediate availability of appropriate backup implants are essential to prevent patient harm.