Maintenance of periarticular joint angles after varization double-level osteotomy for severe valgus deformity: a technical and radiographic mid-term case series

Purpose To assess the restoration and mid-term course of mechanical alignment and periarticular femoral and tibial joint angles after varization double-level osteotomy (DLO) in patients with severe valgus malalignment. Methods This retrospective case series included 13 knees treated with medial closing-wedge distal femoral and high tibial osteotomy between 2011 and 2015. Eight knees were available at a minimum follow-up of five years. Mechanical alignment and periarticular joint angles were assessed preoperatively, six weeks postoperatively, and at final follow-up. Individual radiographic trajectories, conversion to total knee arthroplasty, complications, and postoperative patient-reported outcomes were evaluated descriptively. Results Seven patients with eight knees were assessed after a mean follow-up of 7.5 ± 1.2 years. Mean mTFA changed from 9.6 ± 2.6° valgus preoperatively to − 1.4 ± 1.5° six weeks postoperatively and 0.1 ± 4.7° at final follow-up. Mean mLDFA changed from 86.1 ± 2.2° to 90.5 ± 2.5° postoperatively and 90.2 ± 2.4° at final follow-up; mean mMPTA changed from 92.4 ± 1.6° to 86.4 ± 1.5° and 87.3 ± 2.1°, respectively. Individual trajectories were heterogeneous; one knee developed recurrent valgus alignment with a marked increase in JLCA. None of the eight knees underwent conversion to total knee arthroplasty. Three complications occurred, and implant removal was performed in all knees. Conclusion Within the limitations of this small retrospective case series, varization DLO restored mechanical alignment and periarticular femoral and tibial joint angles in selected patients with severe valgus malalignment. Group-level periarticular bony angles remained close to the early postoperative values at mid-term follow-up, although individual radiographic trajectories were heterogeneous. Larger prospective comparative studies are required to determine clinical effectiveness, complication rates, survivorship, and valgus-specific indication criteria.