Montefiore Medical Center/Albert Einstein College of Medicine, Department of Orthopaedic Surgery, Bronx, NY; Weill Cornell Medical College, Department of Orthopaedic Surgery, New York, NY; Plancher Orthopaedics & Sports Medicine, New York, NY; Orthopaedic Foundation, Stamford, CT.
Plancher Orthopaedics & Sports Medicine, New York, NY; Orthopaedic Foundation, Stamford, CT.
J Arthroplasty. 2021 Sep;36(9):3123-3130. doi: 10.1016/j.arth.2021.04.041. Epub 2021 May 5.
Excessive posterior tibial slope in medial unicompartmental knee arthroplasty (UKA) has been implicated in early failure. The purpose of this study was to evaluate the relationship between preoperative posterior tibial slope and postoperative slope of the implant (PSI) on outcomes in patients with anterior cruciate ligament (ACL) intact and ACL-deficient knees after fixed-bearing medial UKA.
Patients who underwent a medial UKA between 2002 and 2017 with a minimum 3-year follow-up were included. Preoperative posterior tibial slope and postoperative PSI were measured. Outcomes measures included Knee Injury and Osteoarthritis Outcomes Score (KOOS) subscales, Lysholm, and VR-12. Failure was defined as conversion to total knee arthroplasty.
Of 241 knees undergoing UKA, 131 patients (70 women, 61 men; average age of 65 ± 10 years (average BMI of 27.9 ± 4) were included. For all patients, survivorship was 98% at 5 years and 96% at 10 years with a mean survival time for UKA was 15.2 years [95% CI: 14.6-15.7]. No failure had a PSI >7°. There were no superficial or deep infections. There were no significant differences in outcome scores between the ACL intact and the ACL-deficient group; therefore, the data were combined for analysis. At mean 8-year follow-up, KOOS pain scores were better in patients with PSI ≤7° (87 ± 16) than those with PSI >7° (81 ± 15). 76% of patients with PSI ≤7° reached the Patient Acceptable Symptom State for KOOS pain; whereas, 59% of patients with PSI >7° reached PASS for KOOS pain (P = .015).
Patients with postoperative posterior slope of the tibial implant >7° had significantly worse postoperative pain, without conversion to TKA, and with maintenance of high function. In ACL deficient and intact knees, nonrobotically-assisted, fixed-bearing medial UKA had a 96% survivorship at 10 years.
内侧单髁膝关节置换术（UKA）中胫骨后倾角过大与早期失败有关。本研究的目的是评估前交叉韧带（ACL）完整和 ACL 缺失的膝关节接受固定平台内侧 UKA 后，术前胫骨后倾角与术后植入物后倾角（PSI）之间的关系。
纳入 2002 年至 2017 年间接受内侧 UKA 治疗且随访至少 3 年的患者。测量术前胫骨后倾角和术后 PSI。评估指标包括膝关节损伤和骨关节炎评分（KOOS）亚量表、Lysholm 和 VR-12。翻修为全膝关节置换术定义为失败。
共纳入 241 例接受 UKA 的患者，其中 131 例患者（70 例女性，61 例男性；平均年龄 65±10 岁（平均 BMI 为 27.9±4）。所有患者 5 年生存率为 98%，10 年生存率为 96%，UKA 的平均生存时间为 15.2 年[95%CI：14.6-15.7]。没有 PSI>7°的翻修。无浅表或深部感染。ACL 完整与 ACL 缺失组之间的术后评分无显著差异；因此，将数据合并进行分析。在平均 8 年随访时，PSI≤7°的患者 KOOS 疼痛评分（87±16）优于 PSI>7°的患者（81±15）。76%的 PSI≤7°的患者达到 KOOS 疼痛的患者可接受症状状态（Patient Acceptable Symptom State，PASS）；而 PSI>7°的患者中只有 59%达到 PASS（P=0.015）。
术后胫骨植入物后倾角>7°的患者术后疼痛明显加重，但未发生 TKA 翻修，且保持较高功能。在 ACL 完整和缺失的膝关节中，非机器人辅助固定平台内侧 UKA 的 10 年生存率为 96%。
