Duchman Kyle R, Goetz Jessica E, Uribe Bastian U, Amendola Andrew M, Barber Joshua A, Malandra Allison E, Fredericks Douglas C, Hettrich Carolyn M
Department of Orthopaedics & Rehabilitation, University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
Department of Orthopaedics & Rehabilitation, University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
J Shoulder Elbow Surg. 2016 Aug;25(8):1280-7. doi: 10.1016/j.jse.2015.12.016. Epub 2016 Mar 3.
Despite advances in intraoperative techniques, rotator cuff repairs frequently do not heal. Recombinant human parathyroid hormone (rhPTH) has been shown to improve healing at the tendon-to-bone interface in an established acute rat rotator cuff repair model. We hypothesized that administration of rhPTH beginning on postoperative day 7 would result in improved early load to failure after acute rotator cuff repair in an established rat model.
Acute rotator cuff repairs were performed in 108 male Sprague-Dawley rats. Fifty-four rats received daily injections of rhPTH beginning on postoperative day 7 until euthanasia or a maximum of 12 weeks postoperatively. The remaining 54 rats received no injections and served as the control group. Animals were euthanized at 2 and 16 weeks postoperatively and evaluated by gross inspection, biomechanical testing, and histologic analysis.
At 2 weeks postoperatively, rats treated with rhPTH demonstrated significantly higher load to failure than controls (10.9 vs. 5.2 N; P = .003). No difference in load to failure was found between the 2 groups at 16 weeks postoperatively, although control repairs more frequently failed at the tendon-to-bone interface (45.5% vs. 22.7%; P = .111). Blood vessel density appeared equivalent between the 2 groups at both time points, but increased intracellular and extracellular vascular endothelial growth factor expression was noted in the rhPTH-treated group at 2 weeks.
Delayed daily administration of rhPTH resulted in increased early load to failure and equivalent blood vessel density in an acute rotator cuff repair model.
尽管术中技术有所进步，但肩袖修复术常常无法愈合。在已建立的急性大鼠肩袖修复模型中，重组人甲状旁腺激素（rhPTH）已被证明可改善肌腱与骨界面的愈合。我们假设在术后第7天开始给予rhPTH会使已建立的大鼠模型在急性肩袖修复后早期的破坏负荷得到改善。
对108只雄性Sprague-Dawley大鼠进行急性肩袖修复。54只大鼠从术后第7天开始每日注射rhPTH，直至安乐死或术后最多12周。其余54只大鼠不注射，作为对照组。在术后2周和16周对动物实施安乐死，并通过大体检查、生物力学测试和组织学分析进行评估。
术后2周，接受rhPTH治疗的大鼠的破坏负荷显著高于对照组（10.9对5.2 N；P = 0.003）。术后16周，两组之间的破坏负荷没有差异，尽管对照组修复在肌腱与骨界面更频繁地失败（45.5%对22.7%；P = 0.111）。在两个时间点，两组之间的血管密度看起来相当，但在术后2周，rhPTH治疗组细胞内和细胞外血管内皮生长因子表达增加。
在急性肩袖修复模型中，延迟每日给予rhPTH导致早期破坏负荷增加和血管密度相当。
