Changes in demographics and physical activities of the young population have increased the number of patients with medial unicompartmental knee osteoarthritis (OA) requiring surgical intervention.

High tibial osteotomy (HTO) have shown good clinical results in restoring lower extremity alignment, reducing pain, and improving knee function in patients with moderate-to-severe knee osteoarthritis and genu varum deformity.

The aim of this study is to evaluate the relation between correction of the malalignment of the knee and ankle pain and orientation in patient of medial compartment knee osteoarthritis using high tibial osteotomy by recent reports concerning the indications, functional outcomes and complication.

Knee osteoarthritis (OA) is highly prevalent worldwide. It is a leading cause of musculoskeletal disability and associated with activity limitation, working disability and reduced quality of life.

Osteoarthritis can affect any synovial joint in the body, however it occurs most often in weight-bearing joints, with the knee being one of the most commonly affected. Progressive loss of hyaline articular cartilage is often considered the hallmark of the disease. Within the tibiofemoral joint; articular cartilage degradation is most prevalent in the medial compartment.

Changes in demographics and physical activities of the young population have increased the number of patients with medial unicompartmental knee osteoarthritis (OA) requiring surgical intervention.

High tibial osteotomy (HTO) have shown good clinical results in restoring lower extremity alignment, reducing pain, and improving knee function in patients with moderate-to-severe knee osteoarthritis and genu varum deformity.

Prior to the development of total knee arthroplasty (TKA) as a reliable procedure in the 1980s, high tibial osteotomy (HTO) was the most common surgical treatment for varus gonarthrosis.

HTO may influence the alignment and function of the ankle joint. In the case of greater varus deformity where the preoperative talar tilt was increased medial to the ankle or the postoperative correction angle was large, the incidence of arthritis in the ankle joint rose Therefore, it is possible for realignment procedures in the knee HTO to affect ankle joint alignment and ankle symptoms.

Assessment of change in the weight-bearing-line (WBL) ratio of the ankle joints would provide a theoretical basis for post-operative ankle joint pain and osteoarthritis progression after knee arthroplasty or HTO.

The aim of this study is to evaluate the relation between correction of the malalignment of the knee and ankle pain and orientation in patient of medial compartment knee osteoarthritis using high tibial osteotomy by recent reports concerning the indications, functional outcomes and complication .

So this study aimed to investigate the change in the weight-bearing-line (WBL) ratio of the ankle joint and ankle joint line orientation after HTO in patients with genu varum deformity.

Inclusion Criteria:

• Symptomatic medial unicompartment knee arthritis
• Active patients younger than 55 years
• Good range of motion (ROM) .
• Intact lateral compartment

Exclusion Criteria:

• Combined medial and lateral arthrosis.
• Markedly decreased knee range of motion (arc of motion 10°).
• Ligamentous instability.
• Severe joint destruction (≥Ahlback grade III).
• ≥55 years of age.
• Advanced patellofemoral arthritis.
• Rheumatoid arthritis.
• Structural lower extremity deformities.
• Previous operation at knee joint.