Outcomes of Medial Closing-Wedge Distal Femoral Osteotomy for Femoral- and Tibial-Based Valgus Deformity

Background: In carefully selected patients with an arthritic valgus knee, distal femoral osteotomy (DFO) can improve symptoms at medium- to long-term follow-up, reducing osteoarthritis progression. To date, there is no clear evidence in the current literature regarding the role of postoperative joint line obliquity (JLO) in valgus deformity correction. Purpose: To assess the clinical and radiological outcomes of medial closing-wedge DFO (MCW-DFO) for the treatment of valgus knees, considering both tibial- and femoral-based deformities, as well as to verify the efficacy and safety of MCW-DFO according to JLO boundaries (<= 4 degrees). Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective analysis was conducted on a cohort of patients with valgus knees. Patients were divided into 2 groups: femoral-based valgus (FB-V) and tibial-based valgus (TB-V). Knee radiographs were collected before surgery and at the last follow-up. The clinical outcome was evaluated through several validated scores (International Knee Documentation Committee, Knee Society Score, Knee injury and Osteoarthritis Outcome Score, Tegner, Numeric Rating Scale, Crosby-Insall). Results: A total of 30 patients (34 knees) with a mean age of 49.3 +/- 9.1 years were included in the study. The overall mean follow-up was 9.4 +/- 5.9 years. The mean preoperative hip-knee-ankle angle was 187.6 degrees +/- 3.3 degrees (range, 181.5 degrees-191 degrees) and the postoperative angle was 180 degrees +/- 3.1 degrees (range, 176 degrees-185 degrees). Most postoperative JLOs were within the safe zone of <= 4 degrees in both groups (the postoperative JLO was >4 degrees in 4 patients in the TB-V group and 1 patient in the FB-V group), although FB-V knees exhibited significant superior JLO correction (postoperative JLO in the TB-V group: mean, 4.0 degrees +/- 2.5 degrees [P = .1]; postoperative JLO in the FB-V group: mean, 2.4 degrees +/- 1.4 degrees [P = .5]). Significant improvements in all clinical scores were observed in both groups (P < .01). Additionally, the severity of the osteoarthritis did not worsen at the last follow-up. Conclusion: MCW-DFO is an effective procedure for treating pathological valgus knees, regardless of the site of the deformity. Both FB-V and TB-V groups showed comparable improvements in the clinical scores, development of osteoarthritis, and the restoration of a neutral mechanical axis. Notably, FB-V knees achieved more JLO correction compared with the TB-V ones.