A Key Technique for Lateral Unicompartmental Knee Arthroplasty and Its Clinical Efficacy

Abstract Background: Currently, the surgical technique and design of surgical instruments for lateral unicompartmental knee arthroplasty (UKA) in treating lateral knee compartment-specific anatomical structures cannot be replicated. Moreover, few articles have reported on the surgical techniques and clinical effects.These have caused most joint surgeons to dare not to carry out this operationinChina.Here, we report on how we perform this procedure in a replicable manner using redesigned tools, and evaluate subsequent American Knee Society scores, range of motion (ROM), and revision rates.Methods: In this retrospective review (January 2014 through January 2016) we identified 158 patients (35 males and 123 females) who had 160 lateral unicompartmental arthroplasties with a minimum of 36 months follow-up (mean 54, range 36–60 months). The initial symptoms of painful osteoarthritis or osteonecrosis were localized to the lateral compartment. The standard of X-slices is mainly limited to the lateral compartment (Ahlbäck grade II OA or worse) while the articular cartilage of the medial compartment shows no obvious clinical or imaging signs of wear. Any valgus deformity must be correctable to reduce varus stress, and any form of inflammatory arthritis is an absolute contra-indication for lateral UKA.Results: At follow-up, American Knee Society scores (0–100 points) averaged 47.3 ± 1.5 for pain, 97.0 ± 1.7 for clinical outcome, and 97.1 ± 4.1 for function, and ROM averaged 125.5 ± 5.3°. None of the patients had reoperations or revisions.Conclusion: These standard surgical techniques and tools are useful to beginners because they can effectively avoid impingement of the femur against the tibial spine eminences and provide good results.