Introduction: The purpose of the study was to describe the development of the surgical technique of double level osteotomy in patients with severe varus malalignment and to investigate the clinical and radiological outcome. It was hypothesized that good clinical results without a higher complication rate can be achieved by double level osteotomy to normalize joint angles and avoid joint line obliquity even in cases of progressed osteoarthritis.
Materials and methods: Between 2011 and 2014, 33 patients (37 knees) undergoing double level osteotomies (open wedge HTO and closed wedge DFO) were included; of these, 24 patients (28 knees) were available in mean of 18 ± 10 months for the follow-up examination. Indication was symptomatic varus malalignment and medial compartment osteoarthritis. Postoperatively, these patients were assigned to 20 kg partial weight-bearing using two crutches for 6 weeks followed by full weight-bearing. No braces or casts were used. Full weight-bearing long leg anteroposterior radiographs were obtained preoperatively, after 6 weeks and at the time of final follow-up. Mechanical tibiofemoral angle (mTFA), mechanical lateral distal femoral angle (mLDFA) and medial proximal tibia angle (MPTA) were measured. Clinical outcome was evaluated using Lequesne-, Lysholm-, Oxford-, and IKDC-score at the time of follow-up.
Results: The preoperative mTFA of - 11 ± 3° increased to 0 ± 2° at final follow-up. The difference between mTFA-planning and final follow-up was - 2 ± 3° (p < 0.0006). At final follow-up, MPTA and mLDFA were 89.2 ± 2° and 87 ± 2°, respectively. The Lysholm, Oxford, Lequesne, and IKDC scores were 88 ± 13, 44 ± 3, 2 ± 2, and 77 ± 12, respectively.
Conclusions: This study showed that double level osteotomy for the patients with severe varus malalignment and medial compartment osteoarthritis normalises the alignment, joint-angles, avoids joint line obliquity, and leads to good clinical results, despite progressive osteoarthritis.
Level of evidence: Case series, Level IV.
Keywords: DFO; Double level osteotomy; HTO; High tibial osteotomy; Joint line obliquity; Osteotomy.