Rotator cuff tendon to bone insertion site healing

肩袖肌腱在损伤后愈合回骨的能力是有限的， 据报道，手术修复的人体肩袖撕裂有20%-70%的病例发生。外界因素很多 外科医生的控制导致了有限的治愈潜力，包括患者的年龄、泪水大小和时间 从受伤到修复。然而，外科医生可以控制的两个重要因素是外科修复 技术和术后康复方案。虽然已经做了很多关于外科修复的研究 令人惊讶的是，关于肌腱术后康复方案的数据很少。 肩部的骨修复可用于指导临床医生。因此，目前的临床趋势是 修复后不久被动活动肩关节，目前故障发生率较高， 依赖于从肌腱到手部肌腱愈合的数据。然而，来自我们动物模型的数据和 表明肌腱对活动的反应可能不同于愈合到骨骼时的反应 到肌腱。我们最近开发了一种动物模型，在该模型中，肩袖肌腱与骨的愈合 植入部位可作为术后活动水平的一个函数进行仔细评估。固定化是 研究发现，无论是笼子活动还是锻炼，都能产生更好的愈合效果，而且 固定化效果越好，插入部位的性能越好。根据这些结果，我们现在假设 在充分固定一段时间后的再动员将导致改进的插入部位的机械和 与单独固定化相比的结构特性。需要一段时间的固定期来 ‘保护’插入部位并允许适当的细胞外基质(EGM)表达(例如，类型 和III型胶原蛋白、聚集素、核心蛋白和二聚糖)，使得插入部位可以重新形成。因此，积极的一面 再动员的效果需要最短的固定期。具体目标是：1)以下 修复、固定肩部，持续或被动活动，并比较止点 修复后2周、6周、10周、14周、18周和22周的力学、胶原纤维取向和ECM基因表达。 2)修复后，固定肩部2、6、10周，再活动4、8、12周 比较插入部位机制、纤维定向和ECM基因表达与仅在以下情况下的固定 匹配修复后时间点以及随着时间的推移，由于制动已显示出减少 活动范围，3)比较修复前、固定后立即的被动活动范围(ROM 已经停止，在3天、1周、2周和6周后重新动员。

The ability of rotator cuff tendons to heal back to bone following injury is limited, and failure of surgically repaired rotator cuff tears in humans has been reported in 20-70% of cases. Many factors outside of the surgeon's control contribute to the limited healing potential including patient age, tear size, and time from injury to repair. However, two important factors that are within the surgeon's control are surgical repair technique and post-operative rehabilitation protocol. While much research has been done on surgical repair technique, surprisingly, very little data in regard to post-operative rehabilitation protocols following tendon to bone repairs in the shoulder are available to guide clinicians. As a result, the current clinical trend to passively mobilize the shoulder shortly after repair, which is fraught with a high incidence of failure currently, has relied on data from tendon to tendon healing in the hand. However, data from our animal model and that of others indicates that the response of tendon to activity may be different when healing to bone rather than to tendon. We recently developed an animal model in which healing of the rotator cuff tendon to bone insertion site could be carefully evaluated as a function of post-operative activity level. Immobilization was found to result in better healing than either cage activity or exercise and the longer the period of immobilization, the better the insertion site properties. Based on these results, we now hypothesize that remobilization after a sufficient period of immobilization will lead to improved insertion site mechanical and structural properties compared to immobilization alone. A period of immobilization will be necessary to 'protect' the insertion site and to allow for appropriate extracellular matrix (EGM) expression (e.g., type and III collagen, aggrecan, decorin and biglycan) such that the insertion site can re-form. Thus, the positive effect of remobilization requires a minimum period of immobilization. The specific aims are: 1) Following repair, immobilize shoulders either continuously, or with passive motion, and compare insertion site mechanics, collagen fiber orientation and ECM gene expression at 2, 6, 10, 14, 18 and 22 weeks post-repair, 2) Following repair, immobilize shoulders for 2, 6 and 10weeks, then remobilize for 4, 8 and 12 weeks and compare insertion site mechanics, fiber orientation, and ECM gene expression to immobilization only at matching post-repair time points as well as over time, and, since immobilization has been shown to reduce range of motion, 3) Compare passive range of motion (ROM) prior to repair, immediately after immobilization has been discontinued, and after 3 ofays, 1, 2 and 6 weeks of remobilization.