Goutallier D, Postel J M, Boudon R, Lavau L, Bernageau J
Service de Chirurgie Orthopédique et Traumatologique, CHU Henri Mondor, Créteil.
Rev Chir Orthop Reparatrice Appar Mot. 1996;82(4):299-305.
An anatomical study by Warner et al. (1992) showed that an advancement of supra and infra-spinatus of more than 3 cm could be deleterious for the suprascapular nerve or its branches. In pathological conditions, the limit of possible advancement could even be less than 3 cm. The authors wanted to know whether this technique, which they use for the repair of large rotator cuff tears, could have neurological effects in surgical practice.
24 shoulders among 24 patients having had a rotator cuff repair using a musclar advancement have been studied. In 13 cases only the supraspinatus had been advanced, and in 11 cases both supra and infraspinatus have been advanced.
The suprascapular nerve status has been studied postoperatively by EMG. EMG was performed at a mean 8.5 months follow-up. Motor unit potentials were studied at rest and after maximal contraction. Electro-stimulation at Erb's point was used to evaluate muscular latency. All repairs have been controlled by opaque arthrography, and a CT scan grading of muscular fatty degeneration was performed. In 19 cases EMG had also been performed preoperatively.
At revision, 17 EMG were considered normal. In one case there was an impairment of the first primary trunk, already noticed preoperatively. Only 6 EMG anomalies probably related to surgery have been noticed, although the width of the tear in the coronal plane was nearly always of more than 3 cm. 4 of these 6 shoulders had been explored preoperatively by EMG, and were recorded as normal before surgery. Electric impairment was limited to the supraspinatus in 3 cases (increase of muscular latency after single advancement in two cases, polyphasic motor unit potential after double advancement in one case), to the infraspinatus in one case (polyphasic motor unit potentials recorded in the infraspinatus after single advancement of the supraspinatus), and concerned both muscles in 2 cases (increase of muscular latencies after double advancement).
Muscular advancement was usually performed for tears of more than 2.5 cm wide, and so should be deleterious for suprascapular nerve, according to Warner et al. studies. But in most cases no neurological impairment could be observed in surgical practice. This could be due to the fact that the gap to repair is due not only to a loss of substance in the tendons but also to muscular retraction. In a first step, the muscular release allows to correct this muscular retraction ("muscular" advancement). The advancement remaining then to be performed is about 2 cm wide ("tendino-muscular" advancement).
It appears that in surgical practice supra and infraspinatus advancement threatens only moderatly the suprascapular nerve or its branches, even if the width of the tear is greater than 3 cm. Postoperative immobilization in slight lateral elevation further reduces the importance of this advancement.
Warner等人（1992年）的一项解剖学研究表明，冈上肌和冈下肌前移超过3厘米可能会对肩胛上神经或其分支造成损害。在病理情况下，可能的前移限度甚至可能小于3厘米。作者想了解他们用于修复大型肩袖撕裂的这种技术在手术实践中是否会产生神经学影响。
对24例接受肌肉前移修复肩袖的患者的24个肩部进行了研究。13例仅冈上肌前移，11例冈上肌和冈下肌均前移。
术后通过肌电图研究肩胛上神经状态。肌电图在平均随访8.5个月时进行。在静息和最大收缩后研究运动单位电位。使用在Erb点的电刺激来评估肌肉潜伏期。所有修复均通过不透光关节造影进行对照，并对肌肉脂肪变性进行CT扫描分级。19例术前也进行了肌电图检查。
在翻修时，17例肌电图被认为正常。1例存在第一主干损伤，术前已被注意到。尽管冠状面撕裂宽度几乎总是超过3厘米，但仅发现6例可能与手术相关的肌电图异常。这6个肩部中的4个术前进行了肌电图检查，术前记录为正常。电损伤在3例中仅限于冈上肌（2例单次前移后肌肉潜伏期增加，1例双次前移后多相运动单位电位），1例仅限于冈下肌（冈上肌单次前移后冈下肌记录到多相运动单位电位），2例涉及两块肌肉（双次前移后肌肉潜伏期增加）。
根据Warner等人的研究，肌肉前移通常用于宽度超过2.5厘米的撕裂，因此对肩胛上神经应该是有害的。但在大多数手术实践中未观察到神经损伤。这可能是因为需要修复的间隙不仅是由于肌腱实质的丧失，还由于肌肉回缩。第一步，肌肉松解可纠正这种肌肉回缩（“肌肉”前移）。然后剩余需要进行的前移约2厘米宽（“腱-肌肉”前移）。
在手术实践中，似乎冈上肌和冈下肌前移对肩胛上神经或其分支的威胁仅为中度，即使撕裂宽度大于3厘米。术后轻度外展位固定进一步降低了这种前移的影响。
