Department of Orthopaedic Surgery, Arthroscopy and Joint Research Institute, Severance Hospital, Yonsei University College of Medicine, 134, Shinchon-Dong, Seodaemun-Gu, CPO Box 8044, Seoul, 120-752, Republic of Korea.
Arch Orthop Trauma Surg. 2023 Jun;143(6):3251-3258. doi: 10.1007/s00402-022-04681-1. Epub 2022 Nov 11.
To investigate (1) the prevalence of "hidden lesions" and "non-hidden lesions" of subscapularis tendon tears requiring repair during arthroscopic examination that would be missed by a 30° arthroscope, but could be identified by a 70° arthroscope, from the standard posterior portal and (2) the correlation of preoperative internal rotation weakness and findings of magnetic resonance imaging (MRI) indicating hidden lesions.
We retrospectively examined 430 patients who underwent arthroscopic subscapularis repair between was initially nonvisible with a 30° arthroscope but became visible only with a 70° arthroscope from the standard posterior portal. The preoperative and intraoperative findings of the hidden lesion group (n = 82) were compared with those of the non-hidden lesion group (n = 348). 2016 and 2020. A hidden lesion was defined as a subscapularis tendon tear requiring repair that preoperative internal rotation weakness was assessed using the modified belly-press test. Preoperative MR images were reviewed using a systemic approach.
The prevalence of hidden lesions was 19.1% (82/430). No significant difference was found in preoperative internal rotation weakness between the groups. Preoperative MRI showed a significantly lower detection rate in the hidden lesion group than in the non-hidden group (69.5% vs. 84.8%; P = 0.001). The hidden lesions were at a significantly earlier stage of subscapularis tendon tears than the non-hidden lesions, as revealed by the arthroscopic findings (Lafosse classification, degree of retraction; P = 0.003 for both) and MR findings (muscle atrophy, fatty infiltration; P = 0.001, P = 0.005, respectively).
Among the subscapularis tears requiring repair, 19.1% could be identified by a 70° arthroscope, but not by a 30° arthroscope, through the posterior portal. The hidden lesions showed a significantly lower detection rate on preoperative MRI than the non-hidden lesions. Thus, for subscapularis tears suspected on preoperative physical examination, the 70° arthroscope would be helpful to avoid a misdiagnosis.
研究（1）在关节镜检查中，通过标准的后入路，30°关节镜检查下会遗漏需要修复的肩胛下肌腱撕裂的“隐匿性病变”和“非隐匿性病变”，而 70°关节镜可以发现这些病变；（2）术前内旋无力与磁共振成像（MRI）显示隐匿性病变之间的相关性。
我们回顾性分析了 2016 年至 2020 年间 430 例接受关节镜下肩胛下肌腱修复术的患者，这些患者最初在 30°关节镜下不可见，但通过标准的后入路的 70°关节镜可以发现。比较隐匿性病变组（n=82）和非隐匿性病变组（n=348）的术前和术中发现。隐匿性病变定义为肩胛下肌腱撕裂需要修复，术前使用改良的腹部按压试验评估内旋无力。使用系统方法对术前 MRI 进行评估。
隐匿性病变的患病率为 19.1%（82/430）。两组间术前内旋无力无显著差异。隐匿性病变组术前 MRI 显示的检出率明显低于非隐匿性病变组（69.5%比 84.8%；P=0.001）。关节镜检查结果（Lafosse 分类，回缩程度；P=0.003）和 MRI 检查结果（肌肉萎缩，脂肪浸润；P=0.001，P=0.005）显示，隐匿性病变处于肩胛下肌腱撕裂的早期阶段，而非隐匿性病变处于晚期阶段。
在需要修复的肩胛下肌腱撕裂中，19.1%可通过后入路的 70°关节镜发现，但不能通过 30°关节镜发现。隐匿性病变在术前 MRI 上的检出率明显低于非隐匿性病变。因此，对于术前体格检查怀疑的肩胛下肌腱撕裂，70°关节镜有助于避免误诊。
