Purpose: The study reports the 2-year follow-up results of patients with valgus osteoarthritis undergoing total knee arthroplasty (TKA) with a standardized soft-tissue release.
Methods: Between 2008 and 2013, 222 TKAs were performed for valgus osteoarthritis by a single surgeon. A total of 181 TKAs in 164 patients were available for a minimum 2-year follow-up (range 24-87 months). Preoperative and postoperative range of motion (ROM), mechanical alignment, the postoperative medial proximal tibial angle (MPTA), Western Ontario and McMaster Universities Arthritis Index (WOMAC), VF-12 score, visual analogue pain scale (VAS), and the actual UCLA activity score, desired UCLA score, ligamentous stability (medial collateral ligament) and complications and revision rates were recorded.
Results: The ROM increased from a preoperative flexion contracture of 4.7° (range 0-40) and flexion of 110° (range 35-135) to a postoperative mean flexion contracture of 0.1° (range -5 to 10) and flexion of 128° (range 100-140). The mean hip-knee-ankle alignment was changed from 8.4° of mechanical valgus (range 5.3-25.4) to 0.02° of varus alignment (range -2.9 to 4.1). Tibia component angle (MPTA) was 90.4° (range 86.1-93.7). The WOMAC score, VF-12, UCLA and VAS significantly improved after surgery (p < 0.05). Two patients (1.1 %) underwent revision surgery for instability.
Conclusion: The described standardized soft-tissue release (release of the iliotibial band and posterolateral corner) provided excellent clinical results at a minimum 2-year follow-up and can be used safely for a "cook-book" approach to the valgus knee with up to 25° mechanical valgus alignment.
Level of evidence: IV.
Keywords: Lateral soft-tissue release; Standardized approach; Total knee arthroplasty; Valgus osteoarthritis.