Triweekly administration of parathyroid hormone (1-34) accelerates bone healing in a rat refractory fracture model

• Published in: BMC musculoskeletal disorders Vol. 18; no. 1; p. 545
• Main Authors: Kumabe, Yohei, Lee, Sang Yang, Waki, Takahiro, Iwakura, Takashi, Takahara, Shunsuke, Arakura, Michio, Kuroiwa, Yu, Fukui, Tomoaki, Matsumoto, Tomoyuki, Matsushita, Takehiko, Nishida, Kotaro, Kuroda, Ryosuke, Niikura, Takahiro
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 21.12.2017; BioMed Central; BMC
• Subjects: Delayed union; Fracture healing; Fractures (Injuries); Nonunion; Parathyroid hormone (1–34); Parathyroid hormones; Teriparatide; Delayed union; Fracture healing; Nonunion; Parathyroid hormone (1–34); Teriparatide
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-017-1917-2

Some reports have shown that intermittent parathyroid hormone (PTH) (1-34) treatment for patients with delayed union or nonunion have led to successful healing. In this study, we investigated whether systemic intermittent administration of PTH (1-34) has a beneficial effect on bone healing in a rat refractory fracture model. We created a refractory femoral fracture model in 32 rats with periosteal cauterization that leads to atrophic nonunion at 8 weeks after surgery. Half the rats received subcutaneous intermittent human PTH (1-34) injections at a dosage of 100 μg/kg, thrice a week for 8 weeks. The other half received the vehicle only. At 8 weeks after fracture, radiographic, histological and mechanical assessments were performed. Radiographic assessments showed that the union rate was significantly higher in the PTH group than in the control group (P < 0.05). The degree of fracture repair as scored using the Allen grading system in histological assessment was significantly greater in the PTH group than in the control group (P < 0.05). The ultimate stress and stiffness measurements were significantly greater in the PTH group than in the control group (p < 0.05). We demonstrated that triweekly administration of PTH (1-34) increased union rate and accelerated bone healing in a rat refractory fracture model, suggesting that systemic administration of PTH (1-34) could become a novel and useful therapy for accelerating fracture healing in patients at high risk of delayed union or nonunion.