Objective: Review study of the long-term results of Mittelmeier’s high tibial osteotomy for the treatment of degenerative osteoarthritis of the knee.

Patients – Mehod: 110 patients (93 women – 17 men) aged from 50 to 75 years (average 65 years) with knee osteoarthritis of stage II-IV at Ahlback’s grading system, were treated with high tibial osteotomy, in a 15 year period (1988–2002). An overall of 114 osteotomies were performed to the abovementioned patients. All the osteotomies were performed with the same surgical technique, the Mittelmeier’s biplane osteotomy with the use of a specially designed blade plate. 87 patients (73 women – 14 men) were followed-up for a mean time of 10 years (2–14 years). The parameters that evaluated were the knee function, the axial alignment, the complication rate and finally the time that the osteotomy was converted to total arthroplasty.

Results: According to IOWA knee score the result was excellent in 64 patients and good in 15 patients, whereas 9 patients had a poor end result. 3 patients needed a total knee arthroplasty after a meantime of 8 – 10 years. In addition, 2 more patients fulfill the indications of a total arthroplasty. The main complications that occurred were: anterior tibia compartment syndrome in 1 patient, superficial infection in 2 patients, 1 delayed union and 1 mechanical failure of the osteosynthesis. Additionally, in 36 patients there were problems at the site of the fibular osteotomy (injury or entrapment of the superficial peroneal nerve in 12 patients, unremitting pain in 24 patients).

Conlusions: The high tibial osteotomy is an effective though technically demanding method for the operative treatment of the osteoarthritis of the medial compartment of the knee joint.