Abstract:
Rotator cuff (RC) tears are a common source of pain and decreased shoulder strength. Muscle length is known to affect muscle strength, and therefore evaluating changes in supraspinatus muscle length associated with RC pathology, surgical repair, and post-operative recovery may provide insights into functional deficits. Our objective was to develop a reliable MRI-based approach for assessing supraspinatus muscle length. Using a new semi-automated approach for identifying 3D location of the muscle-tendon junction (MTJ), supraspinatus muscle length was calculated as the sum of MTJ distance (distance between 3D MTJ position and glenoid plane) and supraspinatus fossa length (distance between root of the scapular spine and glenoid plane). Inter- and intra-operator reliability of this technique were assessed with intraclass correlation coefficient (ICC) and found to be excellent (ICCs > 0.96). Muscle lengths of 6 patients were determined before RC repair surgery and at 3- and 12-months post-surgery. Changes in normalized muscle length (muscle length as a percentage of pre-surgical muscle length) at 3 months post-surgery varied considerably across patients (16.1 % increase to 7.0 % decrease) but decreased in all patients from 3- to 12-months post-surgery (0.3 % to 17.2 %). This study developed a novel and reliable approach for quantifying supraspinatus muscle length and provided preliminary demonstration of its utility by assessing muscle length changes associated with RC pathology and surgical repair. Future studies can use this technique to evaluate changes over time in supraspinatus muscle length in response to clinical intervention, and associations between muscle length and shoulder function.
摘要:
肩袖(RC)撕裂是疼痛和肩部力量下降的常见原因。已知肌肉长度会影响肌肉力量,因此评估与RC病理相关的冈上肌长度的变化,手术修复,术后恢复可以提供对功能缺陷的见解。我们的目标是开发一种可靠的基于MRI的方法来评估冈上肌长度。使用一种新的半自动方法来识别肌肉-肌腱接头(MTJ)的3D位置,冈上肌长度计算为MTJ距离(3DMTJ位置与关节盂平面之间的距离)和冈上窝长度(肩胛骨根部与关节盂平面之间的距离)之和。使用组内相关系数(ICC)评估了该技术的操作员间和操作员内可靠性,发现该技术非常出色(ICC>0.96)。在RC修复手术前以及手术后3个月和12个月确定了6例患者的肌肉长度。术后3个月的标准化肌肉长度(肌肉长度占手术前肌肉长度的百分比)的变化在患者中差异很大(16.1%增加至7.0%减少),但所有患者在术后3至12个月均有所减少(0.3%至17.2%)。这项研究开发了一种新颖可靠的方法来量化冈上肌长度,并通过评估与RC病理和手术修复相关的肌肉长度变化来初步证明其实用性。未来的研究可以使用这种技术来评估响应临床干预的冈上肌长度随时间的变化。以及肌肉长度和肩部功能之间的关联。