Abstract
Closed-wedge high tibial osteotomy (CWHTO) is more advantageous over open-wedge high tibial osteotomy in the following viewpoints: (1) compression force from the patellar tendon to the osteotomy site contribute to its stability, (2) patellar baja less likely occurs, and (3) hardware implant is placed under the thick muscle, which could prevent risk of irritation and infection. Although conventional CWHTO resects the wedge bone, including the anterior and posterior cortices, interlocking CWHTO preserves them while performing osteotomy for the anterior or posterior cortex with only the proximal or distal osteotomy line, respectively. When the wedge is being closed, the distal fragment is internally rotated overlying the anterior and posterior cortices on the proximal and distal cortices, respectively. As a result, good rotational stability and anterior advancement of the tibial tubercle are obtained. Interlocking CWHTO can be applied for patients with moderate patellofemoral osteoarthritis. Adopting an oblique osteotomy line enables secure multiple screw fixations for a long locking plate with a good fitting, allowing early postoperative weightbearing.