Complications at five years postoperatively.

BackgroundThe Vega System® PS (Aesculap AG, Tuttlingen, Germany) is an advanced, third generation fixed implant that aims to mimic natural knee kinematics by optimizing pivotal motion while reducing surface stress. This study evaluated mid-term survival and clinical outcomes, including range of motion (ROM) of the modern posterior stabilized implant in order to analyse whether this biomechanically successful implant reaches good results in situ.MethodsThe first 100 patients to receive the Vega PS System for total knee arthroplasty were invited to take part in this single centre, single surgeon study. Of these, 84 patients were clinically assessed 5–6 years postoperatively. Data which was obtained during this follow-up examination included revision data, range of motion and clinical scores.ResultsThe 5-year survival rate for exchange of any component was 97.6%, whereby two patients required replacement of the polyethylene gliding surface. Secondary patella resurfacing was performed in 7 patients. Significantly improved results in comparison to the preoperative state could be obtained at the follow-up: KOOS improved from 39.4 to 78.8, SF-12 PCS improved from 32.1 to 42 SF-12 MCS improved from 46 to 53.8 and patella pain improved from 2.7 to 0.3. The mean ROM of the 84 patients after 5 years was 133.1° and mean total KSS was 189.9.Discussion & conclusionsThis study demonstrates a high survival rate of the Vega PS System® and significant improvements in clinical outcomes 5 years after implantation. The obtained mean ROM indicates that this implant provides good flexibility of the knee joint, allowing a high number of activities. However, due to the rate of secondary patella implantation, routine resurfacing of the patella for all PS TKA cases is highly recommended.Clinical trials registrationThe study was registered at clinicaltrials.gov (NCT02802085).背景 Vega System® PS（德国图特林根蛇牌公司（Aesculap AG））是一款第三代先进固定植入物，旨在通过优化枢轴运动、降低表面应力，模拟自然膝关节运动学。本研究旨在评估这款现代化后稳定型植入物的中期生存率与临床结局，包括关节活动度（range of motion, ROM），以分析这款生物力学表现优异的植入物在临床应用中能否取得良好效果。 方法 本研究为单中心、单术者研究，首批接受Vega PS系统全膝关节置换术（total knee arthroplasty, TKA）的100名患者受邀参与试验。其中84名患者于术后5~6年接受了临床随访评估。本次随访采集的数据涵盖翻修相关数据、关节活动度及临床评分结果。 结果 任意部件更换的5年生存率为97.6%，其中2名患者需更换聚乙烯滑动面。7名患者接受了二期髌骨表面置换术。随访结果显示，各项指标较术前均得到显著改善：膝关节损伤和骨关节炎结局评分（Knee Injury and Osteoarthritis Outcome Score, KOOS）从39.4提升至78.8，SF-12躯体健康综合评分（SF-12 Physical Component Summary, SF-12 PCS）从32.1提升至42，SF-12心理健康综合评分（SF-12 Mental Component Summary, SF-12 MCS）从46提升至53.8，髌骨疼痛评分从2.7降至0.3。84名患者术后5年的平均关节活动度为133.1°，平均总膝关节评分（Total Knee Score, KSS）为189.9。 讨论与结论 本研究证实，Vega PS System®植入术后5年生存率较高，临床结局得到显著改善。所得平均关节活动度表明，该植入物可实现良好的膝关节活动度，能够支持患者开展多种日常活动。不过鉴于二期髌骨置换的发生率，建议所有后稳定型全膝关节置换（posterior stabilized total knee arthroplasty, PS TKA）病例均常规开展髌骨表面置换术。 临床试验注册 本研究已在clinicaltrials.gov平台注册（注册号：NCT02802085）。