Arthroscopy combined with lateral closed-wedge distal femoral osteotomy for the treatment of medial unicompartmental knee osteoarthritis caused by femoral varus deformity

Background The present study aimed to assess the clinical effect of arthroscopy combined with lateral closed-wedge distal femoral osteotomy (DFO) for the treatment of medial unicompartmental knee osteoarthritis (KOA) caused by femoral varus deformity. Methods 29 patients were treated with arthroscopy combined with lateral closed-wedge DFO. The degree of lower limb alignment was corrected, the anatomical tibiofemoral angle (aFTA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA) and the joint line convergence angle (JLCA) were measured on a full-length X-ray before and after surgery. Knee joint function was evaluated by VAS score, Lysholm score, subjective IKDC score and Tenger sports score before and after operation. Results At the last follow-up, the correction of lower limb alignment, aFTA and mLDFA of 29 patients were 60.07 ± 2.55%, 176.86 ± 0.89° and 87.14 ± 0.87°, respectively, the differences were statistically significant compared with pre-operation ( P  < 0.001). Meanwhile the JLCA and mMPTA at the last follow-up were 1.06 ± 0.34° and 87.35 ± 0.87°, respectively, the differences were not statistically significant compared with the preoperative values ( P  > 0.05). The differences of VAS score, Lysholm score, subjective IKDC score and Tenger sports score at the last follow-up were 1.24 ± 0.51, 88.62 ± 4.80, 87.59 ± 4.15 and 3.45 ± 0.63, respectively, the differences were statistically significant compared with preoperative ( P  < 0.001). Conclusion Arthroscopy combined with lateral closed-wedge DFO for medial unicompartmental KOA with femoral varus deformity can achieve satisfactory lower limb correction and mid-term clinical efficacy.