DEVELOPMENT AND PRELIMINARY CLINICAL EVALUATION OF A NOVEL MEDIAL HIGH TIBIAL OSTEOTOMY WEDGE FIXATION SYSTEM FOR KNEE OSTEOARTHRITIS

To address the challenges of insufficient support and fixation and unstable limb alignment correction after high tibial osteotomy (HTO), a novel medial high tibial osteotomy wedge fixation system was developed. This study evaluates its mechanical performance, biocompatibility, and preliminary clinical outcomes in patients with knee osteoarthritis (OA). Design and Manufacturing. A wedge-shaped porous metal implant tailored to the medial tibial anatomy was designed and manufactured using 3D printing technology. The implant was made from porous tantalum metal with a high porosity (>75%) and optimal pore size (400–800 μm) to promote bone ingrowth and enhance fixation strength. Mechanical optimization ensured effective stress distribution and stable support. Mechanical Performance Testing. Compression, shear strength, and fatigue tests were conducted to evaluate the implant's stability and durability under dynamic loading conditions. Clinical Study. Ten patients with knee OA underwent HTO using the novel wedge fixation system. Preoperative and postoperative knee function scores (KOOS scores) were recorded, limb alignment was assessed radiographically, and complications were monitored during follow-up. Mechanical tests demonstrated that the implant provided excellent support and fatigue strength under physiological loads, maintaining stable limb alignment over time. Clinical outcomes showed that postoperative KOOS scores significantly improved from a preoperative average of 62 to 93 (12-month follow-up). Radiographic evaluation confirmed effective correction of lower limb alignment from an average 10° varus to a normal range. No implant loosening, migration, or related complications were observed during follow-up. Patients achieved satisfactory recovery with no significant pain or mobility restrictions, and bone ingrowth into the implant was observed. Conclusion. The novel medial HTO wedge fixation system demonstrates excellent mechanical properties and biocompatibility. It effectively fills the osteotomy gap, supports and fixes the tibia, and corrects lower limb alignment. Preliminary clinical results validate its safety and efficacy, offering an innovative solution for treating knee osteoarthritis.