NEURONAL CONTROL OF BONE REGENERATION

Fracture healing is an evolutionarily conserved process that relies on the coordinated activities of a large number of different cell types. Impaired fracture healing affects up to 10% of fracture patients and poses a significant clinical problem as treatment options remain limited. While many risk factors have been identified that negatively affect healing outcomes, paradoxically, the only clinical condition that promotes bone healing is traumatic brain injury (TBI). This study reviews recent evidence for a central role for neural innervation of skeletal tissue in mediating the effects of TBI on bone regeneration. Here, a delicate interplay between sympathetic and CGRP-positive nerve fibers controls callus neovascularisation, which subsequently leads to improved bone healing. Together, the study of TBI and bone regeneration has demonstrated an important role for neural control of fracture repair, with therapeutic and clinical implications.