Lateral opening wedge osteotomy has been utilized in adolescent and adult deformity with the advantage of maintaining the length of the femur. Polyetheretherketone (PEEK) cage can be utilized to fill the opened wedge. Using the cage in opening wedge valgus osteotomy may not only help in bone on-growth healing but also makes the surgery more straightforward through immediate stability of the osteotomy site and allow for earlier mobilization. Between 2017 and 2021, 44 consecutive patients (14 males and 30 females, mean age: 20.8 years, range: 14-36 years) presented with knee valgus deformity. Their mean mechanical tibia-femoral angle (mTFA) at the center of rotation of angulation at the distal femur was 30.7 ° (± 2.74) of valgus. All patients were treated with lateral opening wedge osteotomy using a lumbar PEEK fusion cage designed for posterior lumber interbody fusion and fixed with a distal femoral locking plate. No postoperative casting was used. Modified Hospital for Special Surgery (HSS) knee score pre and postoperatively with a mean follow-up of 36.8 (± 2.8) months. All cases achieved bony union after a mean of 7.5 (± 1.7) weeks, presented with full range of motion, and maintained an mTFA of 7.5° (± 1.8) at the latest follow-up of 36.8 months that had been corrected from a preoperative mTFA of 30.7° (± 2.74). The modified HSS knee score improved from 58.4 (± 1.7) preoperatively to 85.7 (± 2.3) at final follow-up. A PEEK cage augmentation of the femoral lateral opening wedge gap resulted in successful healing and maintenance of the corrected limb axis at a ~3‑year follow‑up.
Zaghloul et al. (Tue,) studied this question.