Total Knee Arthroplasty With Lateral Parapatellar Approach Results in Less Early Postoperative Skin Numbness Than Medial Approach, but No Difference at Mid-Term Follow-Up: A Randomized Control Trial.

Background: Anterior skin numbness is a common complication after total knee arthroplasty (TKA) that may impact postoperative functional outcomes. This study aimed to compare skin numbness area, functional outcomes, and patient satisfaction between patients undergoing TKA with a medial parapatellar approach (medial group) and a lateral parapatellar approach (lateral group). Methods: A prospective randomized study included 68 knees undergoing TKA via the medial parapatellar approach (n = 32) and the lateral parapatellar approach (n = 32) through the midline skin incision. Anterior skin numbness was assessed as the primary outcome using Semmes-Weinstein monofilaments at 6 postoperative timepoints (2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years). Knee range of motion, Knee Injury and Osteoarthritis Outcome Score (KOOS), and patient satisfaction scores were collected. Fifty-nine patients were retrieved at the 2-year final follow-up. Statistical analysis considered repeated outcome measurements with adjusted Results: The lateral group had a significantly smaller area of anterior skin numbness at 2 weeks (11.2 vs 20.2 sq.cm.), 6 weeks (8.2 vs 17.2 sq.cm.), and 3 months (7.8 vs 14.4 sq.cm.) postoperatively compared to the medial group. No difference in the area of numbness was found at 6 months, 1 year, and 2 years. Although the lateral group showed significantly higher satisfaction scores ( Conclusions: Compared to the medial approach, the lateral parapatellar approach in TKA demonstrates a reduced area of early postoperative skin numbness and expedited 6-month recovery, along with marginally superior patient satisfaction scores. However, both approaches yield comparable outcomes in terms of postoperative knee motion and overall functional outcomes.