Steenbrink Frans, Nelissen Rob G H H, Meskers Carel G M, van de Sande Michiel A J, Rozing Piet M, de Groot Jurriaan H
Laboratory for Kinematics and Neuromechanics, Leiden University Medical Center, Leiden, The Netherlands.
Clin Biomech (Bristol). 2010 Mar;25(3):187-93. doi: 10.1016/j.clinbiomech.2009.11.001. Epub 2009 Dec 9.
In massive rotator cuff tears a teres major (TMj) tendon transfer to the insertion of the supraspinatus (SSp) reverses its adduction moment arm into abduction which is supposed to be an adequate salvage procedure. Analysis of muscle function to find biomechanical ground of such success is scarce.
We compared pre- and postoperative clinical outcome of TMj transfer, i.e. Range of Motion, pain, Constant Shoulder scores and arm force. TMj activation was evaluated in 14 patients suffering massive cuff tears using activation ratios to describe the desired 'in-phase' and undesired 'out-of-phase' contribution to the external arm moment. Additionally, we analyzed activation of the latissimus dorsi (LD) and the medial part of the deltoids (DE). The activation ratios were compared to controls and TMj activation ratios were related to clinical outcome.
TMj tendon transfer improved arm function. Pre-operatively, we observed 'out-of-phase'abduction activation of TMj and LD. After transfer patients activated TMj according to its new anatomical position. 'Out-of-phase' LD abduction activation persisted. The clinical improvements coincided with changes in activation ratio of TMj.
'Out-of-phase' TMj adductor activation is associated with compromised arm function in patients with irreparable cuff tears. After transfer, TMj is activated in correspondence with its new anatomical function, which was supportive for the improved arm function.
在巨大肩袖撕裂中，将大圆肌（TMj）肌腱转移至冈上肌（SSp）止点可使其内收力臂转变为外展力臂，这被认为是一种有效的挽救手术。对肌肉功能进行分析以探寻这种成功的生物力学基础的研究较少。
我们比较了TMj转移术前和术后的临床结果，即活动范围、疼痛、Constant肩关节评分和手臂力量。使用激活率评估了14例患有巨大肩袖撕裂的患者的TMj激活情况，以描述其对外侧手臂力矩的期望“同相”和不期望“异相”贡献。此外，我们分析了背阔肌（LD）和三角肌内侧部分（DE）的激活情况。将激活率与对照组进行比较，并将TMj激活率与临床结果相关联。
TMj肌腱转移改善了手臂功能。术前，我们观察到TMj和LD的外展激活“异相”。转移后，患者根据其新的解剖位置激活TMj。LD外展激活“异相”持续存在。临床改善与TMj激活率的变化一致。
TMj内收肌激活“异相”与不可修复肩袖撕裂患者的手臂功能受损有关。转移后，TMj根据其新的解剖功能被激活，这对改善手臂功能有支持作用。
