High tibial osteotomy is a surgical procedure performed in the context of knee osteoarthritis to relieve pressure on the worn portion of the knee joint. It is usually performed in cases of arthritis affecting only one part (compartment) of the knee, and the goal is to remove pressure from the damaged area and move it to another compartment of the knee that has healthy cartilage. During surgery, a wedge of bone is removed or added under the knee joint depending on the location of the arthritic lesion.
High tibial osteotomy is usually used for young, active patients with isolated osteoarthritis of one compartment of the knee. It is also performed to treat many knee conditions such as arthritis with knee alignment disorders, interosseous osteochondritis, osteonecrosis, posterior instability, and cartilaginous lesions. Contraindications to surgery include inflammatory arthritis, obesity, connective instability of the knee, knee interlocking, and patellofemoral arthritis.
The goal of surgery is to free the involved portion of the joint by correcting the misalignment of the tibia and to maintain the plane of the joint perpendicular to the mechanical axis of the foot. There are two techniques that can be used: open wedge osteotomy and closed wedge osteotomy.
Closed wedge osteotomy is the most commonly used technique for high tibial osteotomy. In this procedure, an incision is made in front of the knee, two incisions are made in the bone, and a small wedge of bone is removed from the upper part of the tibia. With proper manipulation, the bone fragments are brought together and the space created by the removed bone wedge is filled. Plates and screws are then used to fix the bone segments and the osteotomy is healed. This technique relieves pressure from the damaged area of the joint and helps transfer some of the load to the outside of the knee, where the cartilage is still intact.
In an open wedge osteotomy, an incision is made in front of the knee, just below the patella, and an incision is made on the medial surface of the upper end of the tibia. The space of the wedge opening is filled with bone grafts and if required, plates and screws can be fixed to further support the surgical site during the healing process.
Postoperatively, after a tibial osteotomy, the patient cannot immediately load the affected limb, unlike with knee arthroplasties, and recovery is longer. However, after the osteotomy has healed, patients can perform high-energy activities. Therefore, the procedure is more suitable for younger, active and more demanding patients.
Tibial osteotomy has a success rate of 50-85% at 10 years. Complications of high tibial osteotomy include infection, skin necrosis, pseudarthrosis (failure of bones to heal), recurrence of deformity, neurovascular damage, failure to correct deformity, high patella, compartment syndrome and deep vein thrombosis.