کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4074242 1267003 2014 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The role of muscle imbalance in the pathogenesis of shoulder contracture after neonatal brachial plexus palsy: a study in a rat model
ترجمه فارسی عنوان
نقش عدم تعادل عضلانی در پاتوژنز انقباض شانه بعد از فلج پلکسی گریزی نوزادان: مطالعه در یک مدل موش
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی ارتوپدی، پزشکی ورزشی و توانبخشی
چکیده انگلیسی

BackgroundAn internal rotation contracture of the shoulder is common after neonatal brachial plexus injuries due to subscapularis shortening and atrophy. It has been explained by 2 theories: muscle denervation and muscle imbalance between the internal and external rotators of the shoulder. The goal of this study was to test the hypothesis that muscle imbalance alone could cause subscapularis changes and shoulder contracture.Materials and methodsWe performed selective neurectomy of the suprascapular nerve in 15 newborn rats to denervate only the supraspinatus and the infraspinatus muscles, leaving the subscapularis muscle intact. After 4 weeks, passive shoulder external rotation was measured and a 7.2-T magnetic resonance imaging scan of the shoulders was used to determine changes in the infraspinatus and subscapularis muscles. The subscapularis muscle was weighed to determine the degree of mass loss. An additional group of 10 newborn rats was evaluated to determine the sectional muscle fiber size and muscle area of fibrosis by use of images from type I collagen immunostaining.ResultsThere was a significant decrease in passive shoulder external rotation, with a mean loss of 66°; in the thickness of the denervated infraspinatus, with a mean loss of 40%; and in the thickness and weight of the non-denervated subscapularis, with mean losses of 28% and 25%, respectively. No differences were found in subscapularis muscle fiber size and area of fibrosis between shoulders after suprascapular nerve injury.ConclusionsOur study supports the theory that shoulder muscle imbalance is a cause of shoulder contracture in patients with neonatal brachial plexus palsy.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Shoulder and Elbow Surgery - Volume 23, Issue 7, July 2014, Pages 1003–1009
نویسندگان
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