Chen Zhijie, Chen Kaizhe, Yan Yufei, Feng Jianmin, Wang Yi, Liu Zhihong, Yang Qingming, He Chuan
Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai, 200025, People's Republic of China.
Arthroplasty. 2021 Apr 12;3(1):11. doi: 10.1186/s42836-021-00070-y.
To evaluate the effect of medial posterior tibial slope (PTS) on mid-term postoperative range of motion (ROM) and functional improvement of the knee after medial unicompartmental knee arthroplasty (UKA).
Medical records of 113 patients who had undergone 124 medial UKAs between April 2009 through April 2014 were reviewed retrospectively. The mean follow-up lasted 7.6 years (range, 6.2-11.2 years). Collected were demographic data, including gender, age, height, weight of the patients. Anteroposterior (AP) and lateral knee radiographs of the operated knees were available in all patients. The knee function was evaluated during office follow-up or hospital stay. Meanwhile, postoperative PTS, ROM, maximal knee flexion and Hospital for Special Surgery (HSS) knee score (pre-/postoperative) of the operated side were measured and assessed. According to the size of the PTS, patients were divided into 3 groups: group 1 (<4°), group 2 (4° ~ 7°) and group 3 (>7°). The association between PTS and the knee function was investigated.
In our cohort, the average PTS was 2.7° ± 0.6° in group 1, 5.6° ± 0.9° in group 2 and 8.7° ± 1.2° in group 3. Pairwise comparisons showed significant differences among them (p < 0.01). The average maximal flexion range of postoperative knees in each group was 112.4° ± 5.6°, 116.4° ± 7.2°, and 117.5° ± 6.1°, respectively, with significant difference found between group 1 and group 2 (p < 0.05), and between group 1 and group 3 (p < 0.05). However, the gender, age, and body mass index (BMI) did not differ between three groups and there was no significant difference between groups in terms of pre-/postoperative HSS scores or postoperative knee ROM.
A mid-term follow-up showed that an appropriate PTS (4° ~ 7°) can help improve the postoperative flexion of knee. On the other hand, too small a PTS could lead to limited postoperative knee flexion. Therefore, the PTS less than 4° should be avoided during medial UKA.
评估胫骨后内侧斜率（PTS）对内侧单髁膝关节置换术（UKA）术后中期膝关节活动范围（ROM）及功能改善的影响。
回顾性分析2009年4月至2014年4月期间113例行124次内侧UKA手术患者的病历。平均随访时间为7.6年（范围6.2 - 11.2年）。收集患者的人口统计学数据，包括性别、年龄、身高、体重。所有患者均有患侧膝关节前后位（AP）和侧位X线片。在门诊随访或住院期间评估膝关节功能。同时，测量并评估患侧术后PTS、ROM、最大膝关节屈曲度及特殊外科医院（HSS）膝关节评分（术前/术后）。根据PTS大小将患者分为3组：第1组（<4°）、第2组（4°~7°）和第3组（>7°）。研究PTS与膝关节功能之间的关联。
在我们的队列中，第1组平均PTS为2.7°±0.6°，第2组为5.6°±0.9°，第3组为8.7°±1.2°。两两比较显示组间差异有统计学意义（p< 0.01）。每组术后膝关节平均最大屈曲范围分别为112.4°±5.6°、116.4°±7.2°和117.5°±6.1°，第1组与第2组之间（p< 0.05）以及第1组与第3组之间（p< 0.05）差异有统计学意义。然而，三组之间性别、年龄和体重指数（BMI）无差异，术前/术后HSS评分或术后膝关节ROM在组间也无显著差异。
中期随访表明，合适的PTS（4°~7°）有助于改善术后膝关节屈曲度。另一方面，PTS过小可能导致术后膝关节屈曲受限。因此，内侧UKA手术期间应避免PTS小于4°。
