Lateral Epicondylar Sliding Osteotomy in Total Knee Arthroplasty for Rigid Valgus Deformity
Valgus knees are defined as those with 10° of valgus alignment of the major mechanical axis on standing AP radiographs. Severe valgus deformity is associated with poorer outcomes and more difficult surgery compared with severe varus deformity. Current surgical techniques correct alignment, gap balancing, and rotation of the components in valgus knees by releasing the lateral soft-tissue structures, such as the iliotibial band, posterolateral capsule, popliteal tendon, and hamstring tendons. However, in patients with a severe or rigid valgus deformity, these releases cause excessive disruption, do not adequately balance the soft tissues, and may lead to postoperative overcorrection and mediolateral instability. The goal is to prevent such instability and to use a less invasive treatment option to manage the external compartment ligaments of the arthritic valgus knee. A balancing technique that involves a sliding osteotomy of the lateral aspect of the lateral femoral condyle, as described by Brilhault, allows for precise lengthening of the lateral structures, and internal fixation with the use of screws affords immediate stability and normal postoperative management.
This video shows the use of a tibial-first, noncemented mobile-bearing prosthesis to demonstrate the effectiveness of this procedure. The knee is exposed via a lateral parapatellar arthrotomy. Five patients (four women, one man) with a mean age of 74 years (range, 70 to 81 years) at the time of surgery and a fixed valgus deformity underwent a sliding osteotomy of the lateral femoral condyle as described. At a minimum follow-up of 2 years, the patients were clinically and radiographically evaluated. All of the procedures were successful, and no major complications were reported. The mean postoperative Knee Society Score was 89 points (range, 85 to 98 points), and the mean postoperative Function Score was 90 points (range, 78 to 99 points). The mean preoperative valgus angle was 17° (range, 16° to 22°), and the mean postoperative valgus angle was 2° (range, 0° to 3°). No conversion to a semiconstrained or constrained knee prosthesis was necessary. The lateral femoral sliding osteotomy technique for ligamentous balancing is a reliable and effective surgical procedure to restore stable alignment in patients with a rigid valgus knee deformity, decreasing the need for lateral soft-tissue release and the use of a semiconstrained or constrained knee prosthesis.