Supracondylar Osteotomy in Valgus Knee: Angle Blade Plate Versus Locking Compression Plate.

Background: There are few studies comparing the biomechanical properties of angled blade plate and locking compression plates in supracondylar osteotomy. In the current randomized study, we prospectively compared the clinical and radiological outcomes of supracondylar osteotomy using these two plates.

Methods: Forty patients with valgus knee malalignment were randomly assigned to two equal numbered groups: angled blade plate and locking compression plates. All of the patients underwent medial closing wedge supracondylar osteotomy and were followed for one year. Before and after the operation the valgus angle and mechanical lateral distal femoral angle were compared between groups. Also, the rate of complications were compared.

Results: After the operation, the mean valgus angle and mechanical lateral distal femoral angle improved significantly in the two groups (P<0.001). Although, the preoperative amount of the valgus angle and mechanical lateral distal femoral angle were the same, at the last visit the valgus angle (5.4±2.1 versus 3.1±1.8; P=0.032) and mechanical lateral distal femoral angle (87.6±2 versus 89.7±3.2; P=0.041) were significantly lower and higher in the angled blade plate group, respectively. Nonunion occurred in four patients (20%) in the locking compression plates group (P=0.35).

Conclusion: Based on having a larger valgus angle and mechanical lateral distal femoral angle correction in the angled blade plate group and considerable rate of nonunion in the locking compression plate group, the authors recommend using the angled blade plate for fixation of medial closing wedge supracondylar osteotomy for patients with valgus malalignment. However, more long-term studies are required.