Delayed administration of recombinant human parathyroid hormone improves early biomechanical strength in a rat rotator cuff repair model.

Journal Article (Journal Article)

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: Delayed daily administration of rhPTH resulted in increased early load to failure and equivalent blood vessel density in an acute rotator cuff repair model.

Full Text

Duke Authors

Cited Authors

  • Duchman, KR; Goetz, JE; Uribe, BU; Amendola, AM; Barber, JA; Malandra, AE; Fredericks, DC; Hettrich, CM

Published Date

  • August 2016

Published In

Volume / Issue

  • 25 / 8

Start / End Page

  • 1280 - 1287

PubMed ID

  • 26948004

Electronic International Standard Serial Number (EISSN)

  • 1532-6500

Digital Object Identifier (DOI)

  • 10.1016/j.jse.2015.12.016


  • eng

Conference Location

  • United States