To evaluate the safety and efficacy of open wedge high tibial osteotomy(OWHTO) in the treatment of Medial compartment knee osteoarthritis associated with varus deformity.

Clinical data of 96 patients with knee osteoarthritis who received OWHTO treatment in the department of orthopedics of Beijing Luhe Hospital Affiliated to Capital Medical University from January 2018 to January 2020 were collected. The preoperative and postoperative hip-knee-ankle (HKA), visual analogue scale (VAS) of pain, American Knee Society score (KSS) were compared and analyzed by pared-samples t test. The operative time, intraoperative blood loss, incision length, and postoperative complication incidence was calculated.

All the 96 patients were followed up for six to 30 months. All the patients were corrected for extraarticular deformities. The operation time was (98±8) min, the intraoperative blood loss was (278 ±58) ml, and the incision length was (7.2±1.8) cm. The hip knee ankle angle (HKA) decreased from (186.2±1.5)°to (180.4±1.2)° (t=5.19, P<0.037). The visual analogue scale (VAS) score decreased from (2.8±1.3) preoperatively to (1.1±0.4) postoperatively (t=4.82, P<0.043), The clinical score of KSS increased from (59.8±4.4) preoperatively to (81.5± 6.5) postoperatively (t =-13.17, P<0.011). KSS functional score increased from (60.2±11.4) preoperatively to (82.7±7.7) after operation (t=-13.17, P<0.019). The postoperative Caton Deschamps index (CDI) were (0.91±0.12), and the condition of patella baja did not occur. All the osteotomies healed and only five cases encountered complications(5.2%), including two cases of fever incision infection and three cases of subcutaneous hematoma.

OWHTO is a safe and effective alternative for medial compartment knee osteoarthritis with Varus deformity. Indications should be strictly observed in clinical practice. Operation specifications should be followed to reduce the occurrence of complications.