The Effects of Overuse Combined With Intrinsic or Extrinsic Alterations in an Animal Model of Rotator Cuff Tendinosis

摘要: An in vivo animal model was used to evaluate overuse and plus intrinsic tendon injury or extrinsic compression the development of rotator cuff injury. Forty-four male Sprague-Dawley rats were divided into groups 22. Each left shoulder received an (treadmill running), each right only overuse. Eleven from group sacrificed at 4 8 weeks. Supraspinatus tendons evaluated histologically geometrically biomechanically. Ten constituted a cage-activity control group. Both supraspinatus experimental had increases cellularity collagen disorganization changes cell shape compared with tendons. Tendons exhibited worse histologic grade than those alone. The cross-sectional area both significantly more increased on average overuse-alone Biomechanically, tissue moduli overuse/intrinsic weeks overuse/extrinsic lower Tissue overuse/injury This study demonstrated that damage can be caused by injury, compression,