Hashimoto Eiko, Ochiai Nobuyasu, Kenmoku Tomonori, Sasaki Yu, Yamaguchi Takeshi, Kijima Takehiro, Sasaki Yasuhito, Ohtori Seiji, Takahashi Kazuhisa
Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan.
Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan.
J Shoulder Elbow Surg. 2016 Dec;25(12):2025-2033. doi: 10.1016/j.jse.2016.04.024. Epub 2016 Jul 14.
The major cause of rotator cuff tears in humans is thought to be tendon degeneration. Although some studies have reported chronic rotator cuff tear models in animals, few studies of chronic rat models have demonstrated persistent defects for a relatively long time. The purpose of this study was to establish a chronic rotator cuff tear model in the rat and to evaluate the model macroscopically and histologically.
Sixty Sprague Dawley rats were divided into 2 groups: tendon detachment only (tear group) and tendon detachment plus figure resin (chronic group). The contralateral shoulder served as a sham-operated control (sham group). In the tear group, the supraspinatus and infraspinatus tendons were completely detached. In addition to cuff detachment, figure resin was placed on the greater tuberosity to prevent cuff reattachment and scar formation in the chronic group. Macroscopic and histologic changes were assessed at 4 and 12 weeks after surgery.
A full-thickness cuff defect was observed in all chronic-group rats at both 4 and 12 weeks after surgery, and it could be repaired secondarily by traction in lower tension. However, no cuff defects were observed in the tear group because of obvious scar tissue formation. On histologic evaluation, progressive tendon degeneration, muscle atrophy, and fatty infiltration were observed in the chronic model at 12 weeks after surgery.
We established a rat model of chronic rotator cuff tears using figure resin. This chronic rotator cuff tear model might be useful for further clinical investigations of rotator cuff repair.
人类肩袖撕裂的主要原因被认为是肌腱退变。尽管一些研究报道了动物慢性肩袖撕裂模型，但很少有关于慢性大鼠模型的研究能在相对较长时间内证明存在持续的缺损。本研究的目的是建立大鼠慢性肩袖撕裂模型，并从宏观和组织学角度对该模型进行评估。
将60只Sprague Dawley大鼠分为2组：仅肌腱切断组（撕裂组）和肌腱切断加塑形树脂组（慢性组）。对侧肩部作为假手术对照（假手术组）。在撕裂组中，冈上肌和冈下肌腱被完全切断。在慢性组中，除了切断肩袖外，还在大结节上放置塑形树脂以防止肩袖重新附着和瘢痕形成。在术后4周和12周评估宏观和组织学变化。
在术后4周和12周，所有慢性组大鼠均观察到全层肩袖缺损，且可通过较低张力下的牵引进行二期修复。然而，由于明显的瘢痕组织形成，撕裂组未观察到肩袖缺损。组织学评估显示，术后12周慢性模型中观察到进行性肌腱退变、肌肉萎缩和脂肪浸润。
我们使用塑形树脂建立了大鼠慢性肩袖撕裂模型。该慢性肩袖撕裂模型可能有助于肩袖修复的进一步临床研究。
