The Effect of Open Wedge High Tibial Osteotomy on the Posterior Tibial Slope In Skeletally Mature Patient

High tibial osteotomy has been established as an efficient surgical intervention for young patients with uni-compartmental osteoarthritis of the knee. Medial opening wedge high tibial osteotomy is a well established surgery for patients with medial compartment knee osteoarthritis its most notable advantages include the precision of intraoperative angular correction, absence of the risk of peroneal nerve palsy in fibular osteotomy, absence of leg shortening, and preservation of bone stock.

The principle of this surgery involves the realignment of the lower extremity to shift the load distribution from the medial compartment into the lateral compartment, thus leading to a decrease in symptoms related to medial compartment knee Osteoarthritis However, medial opening wedge high tibial osteotomy is also known to affect the posterior tibial slope angle , and it is reported that posterior tibial slope angle increases after medial opening wedge high tibial osteotomy .

Satisfactory outcomes after surgery require optimal realignment both in the sagittal and coronal planes; in fact, poor realignment could lead to unsatisfactory clinical outcomes. An unintentional increase in posterior tibial slope angle after medial opening wedge high tibial osteotomy may influence knee kinematics and stability in the sagittal plane, which could lead to anterior translation of the tibial plateau, anterior shift of the tibiofemoral contact area, and subsequent redistribution of pressure into the posterior tibial plateau (particularly in knees with injured anterior cruciate ligaments). These conditions could result in articular cartilage degradation and further knee disability

Inclusion criteria

• Age: 20 : 65 years
• Genuvarus deformity
• 70° of range of motion
• Medial uni-compartmental osteoarthritis.

Exclusion criteria

• Posterior instability (relating to the posterior cruciate ligament)
• Body Mass Index under 30
• Sever Genuvarus > 20 degree