Department of Orthopaedic Surgery, Beijing Jishuitan Hospital, Fourth Clinical College of Peking University, No. 31 Xinjiekou East Street, Xicheng District, Beijing 100035, China.
Department of Orthopaedic Surgery, Beijing Jishuitan Hospital, Fourth Clinical College of Peking University, No. 31 Xinjiekou East Street, Xicheng District, Beijing 100035, China.
Knee. 2022 Aug;37:103-111. doi: 10.1016/j.knee.2022.06.004. Epub 2022 Jun 23.
A forgotten joint is considered the ultimate goal of joint replacement. We aim to explore the predictive factors of a forgotten joint after fixed-bearing unicompartmental knee arthroplasty (UKA).
This retrospective cohort study used prospectively collected data from 302 cases of medial-compartment UKA with a minimum of 2-year follow-up. The primary outcome was the achievement of a forgotten joint after UKA, according to the Forgotten Joint Score (FJS-12) at the last follow-up. Patients with FJS-12 > 84 were considered to have forgotten UKA. Univariate and multivariate logistic regression analyses were conducted with preoperative patient characteristics and surgery-related factors as potential predictors.
Of patients, 94 (31.1%) achieved a forgotten joint post-surgery. Multivariate logistic regression analysis revealed that preoperative hip-knee-ankle angle (HKAA), anatomic lateral distal femoral angle (aLDFA), and postoperative HKAA and HKAA changes were independent predictors of a forgotten joint. The probability of achieving a forgotten joint increased by 29% (OR = 1.29, 95% CI: 1.12-1.51) with a 1° increase in aLDFA. Preoperative HKAA, postoperative HKAA, HKAA changes (ΔHKAA), and outcomes exhibited a non-linear relationship. The probability of achieving a forgotten joint was the highest with preoperative HKAA > 172.0°, postoperative HKAA of 176.0-178.5°, and ΔHKAA < 5.5°.
To achieve the forgotten joint state, the ideal HKAA range after medial fixed-bearing UKA is 176.0-178.5° and ΔHKAA should be <5.5°. Patients with smaller preoperative aLDFA and HKAA have a lower probability of achieving a forgotten joint after UKA.
被遗忘的关节被认为是关节置换的终极目标。我们旨在探讨固定平台单髁膝关节置换（UKA）后达到被遗忘关节的预测因素。
本回顾性队列研究使用前瞻性收集的 302 例内侧间室 UKA 数据，随访时间至少 2 年。主要结果是根据最后一次随访时的遗忘关节评分（FJS-12）评估 UKA 后是否达到被遗忘关节。FJS-12>84 分的患者被认为 UKA 被遗忘。使用单变量和多变量逻辑回归分析，以术前患者特征和手术相关因素作为潜在预测因素。
94 例（31.1%）患者术后达到被遗忘关节。多变量逻辑回归分析显示，术前髋膝踝角（HKAA）、解剖外侧远端股骨角（aLDFA）和术后 HKAA 及 HKAA 变化是达到被遗忘关节的独立预测因素。aLDFA 每增加 1°，达到被遗忘关节的可能性增加 29%（OR=1.29，95%CI：1.12-1.51）。术前 HKAA、术后 HKAA、HKAA 变化（ΔHKAA）和结果呈非线性关系。术前 HKAA>172.0°、术后 HKAA 为 176.0-178.5°和 ΔHKAA<5.5°时，达到被遗忘关节的可能性最高。
为了达到被遗忘关节状态，内侧固定平台 UKA 后理想的 HKAA 范围为 176.0-178.5°，ΔHKAA 应<5.5°。术前 aLDFA 和 HKAA 较小的患者 UKA 后达到被遗忘关节的可能性较低。
