Department of Veterans Affairs, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA.
J Orthop Res. 2013 Mar;31(3):421-6. doi: 10.1002/jor.22233. Epub 2012 Sep 18.
Rotator cuff pathology is the most common shoulder problem seen by orthopedic surgeons. Rotator cuff muscle fatty infiltration and muscle atrophy are common in larger tears and are considered predicting factors for the prognosis of cuff repair. Clinically, MRI is the gold standard in determining fatty infiltration and muscle atrophy; however, analysis for MRI imaging is primarily qualitative in nature with the results lacking further validation. We have recently developed a mouse model of rotator cuff tears. The goal of this study is to quantify and verify rotator cuff muscle atrophy and fatty infiltration using high-resolution MRI in our mouse model. The rotator cuff muscles were analyzed for fat using a triglyceride quantification assay (TQA), muscle volume was measured through water displacement (WD), and histology. The study revealed that MRI had a high correlation with fat as measured with histology and TQA (R(2) =098). MRI also correlated well with atrophy measured with WD and wet weight. This suggests that MRI is a reliable modality in evaluating the progression of fatty infiltration and muscle atrophy following rotator cuff tears in a small animal model.
肩袖病变是骨科医生最常见的肩部问题。肩袖肌肉脂肪浸润和肌肉萎缩在较大的撕裂中很常见，被认为是肩袖修复预后的预测因素。临床上，MRI 是确定脂肪浸润和肌肉萎缩的金标准；然而，MRI 成像的分析主要是定性的，结果缺乏进一步验证。我们最近开发了一种肩袖撕裂的小鼠模型。本研究的目的是使用高分辨率 MRI 定量和验证我们的小鼠模型中的肩袖肌肉萎缩和脂肪浸润。使用甘油三酯定量分析 (TQA) 分析肩袖肌肉中的脂肪，通过水置换 (WD) 和组织学测量肌肉体积。研究表明，MRI 与组织学和 TQA 测量的脂肪具有高度相关性 (R(2) = 0.98)。MRI 与 WD 和湿重测量的萎缩也有很好的相关性。这表明 MRI 是一种可靠的方法，可用于评估小动物模型中肩袖撕裂后脂肪浸润和肌肉萎缩的进展。
