Biplanar derotation osteotomy of the proximal tibia with anterior longitudinal wedge resection: indications and surgical technique.

Background: Axial torsional deformities of the lower limbs cause altered knee joint mechanics, affecting the gait and originating patellofemoral instability and pain. Torsional osteotomies intend to correct the longitudinal axis alignment, bringing it to normal threshold values and decreasing the patellofemoral malfunction. Aims: To describe a novel technique of a biplanar derotation proximal tibial osteotomy with an anteromedial approach and anterior longitudinal wedge resection and to provide indications for the procedure. Technique: Eligible patients are those with EETT with altered Q-angle and alternative Q-angle (second toe test) in whom a correction of ≤20° is needed. This surgical technique uses a derotational osteotomy in the proximal tibia with an anteromedial approach, medial wedge resection, and fixation with a 4 × 4 locking plate. The biplanar supra-tuberosity derotation osteotomy is performed to correct the EETT and the TT-TG distance simultaneously. The infra-tuberosity osteotomy is performed to correct the EETT when the TT-TG is not altered. Conclusion: This novel biplanar tibial osteotomy uses an anteromedial approach, the most used in knee surgery, to perform an anterior longitudinal wedge resection, allowing 15 to 20-degree corrections of rotational deformities of the tibia. A meticulous clinical and radiological patient selection is required to achieve an alignment on the threshold of normality.