[Mid-term effects of unicompartmental knee arthroplasty combined with anterior cruciate ligament reconstruction for the medial compartment osteoarthritis with anterior cruciate ligament deficiency by proportioning with the pure medial compartment osteoarthritis].

Objective: To evaluate the mid-term efficacy of one-stage unicompartmental knee arthroplasty (UKA) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of medial compartment osteoarthritis (OA) with ACL deficiency. Methods: Retrospective cohort study. The clinical data of 13 patients (14 knees) who underwent UKA with ACL reconstruction for knee medial compartment OA combined with ACL deficiency in Wangjing Hospital of China Academy of Chinese Medical Sciences from January 2012 to January 2020 were retrospective analyzed. A 1∶1 proportioning study was conducted with 13 patients (14 knees) who underwent UKA due to medial compartment OA with intact ACL during the same period. The matching conditions were the same gender, age, surgical side, anesthesia method, comorbidities, and imaging lesions. There were 26 patients (28 knees) in the two groups, including 6 males (6 knees) and 20 females (22 knees), aged (58.9±4.2) years. The range of motion (ROM) and Oxford Knee Score (OKS) were used to evaluate the knee joint function at the last follow-up. The anteroposterior, lateral and axial X-ray films of the knee joint and the weight-bearing full-length X-ray films of the lower limbs were taken during follow-up. The hip knee ankle (HKA) angle, the posterior slope angle (PSA) of tibial prosthesis, and the anterior tibial translation (ATT) were recorded and compared between the two groups. The progression of lateral compartment OA, prosthesis loosening, and dislocation were evaluated. The mid-term follow-up clinical efficacy of the two surgical methods was compared, and the etiology of the patients was analyzed to verify the clinical efficacy and patient selection of one-stage UKA combined with ACL reconstruction. Results: The follow-up time of the two groups was (7.14±2.45) years. At the last follow-up, there was no significant difference in joint ROM between the combined group and the UKA group (120.90°±2.95° vs 122.29°±3.22°, P =0.260). There was no significant difference in OKS score between the two groups [(42.50±1.99) vs (43.21±2.26), P =0.380]. There was no significant difference in HKA angle and ATT distance between the two groups before operation (both P >0.05). At the last follow-up, the results were better than those before operation, and the differences were statistically significant (both P <0.05). At the last follow-up, there was no significant difference in HKA Angle between the combined group and the simple group (177.79°±1.25 ° vs 177.86°±1.29°, P =0.880). Tibial prosthesis PSA and ATT distance were not significantly different between the two groups [(4.57°±0.94° vs 4.50°±1.34°and (0.21±0.89) mm vs (0.14±1.35) mm, both P >0.05)]. There was no prosthesis loosening and obvious progression of lateral compartment OA in both groups at the last follow-up. Conclusion: For young patients with medial compartment OA secondary to ACL deficiency, UKA combined with ACL reconstruction is recommended, it can obtain good mid-term results.