Pedicled Vascularized Bone Grafts for Posterior Occipitocervical and Cervicothoracic Fusion: A Cadaveric Feasibility Study.

Abstract

Arthrodesis is critical for achieving favorable outcomes in reconstructive spine surgery. Vascularized bone grafts (VBGs) have been successfully used to augment fusion rates in a variety of skeletal pathologies, and pedicled VBG has numerous advantages over free transfer VBG. Pedicled VBG has not previously been described for the posterior occipitocervicothoracic spine. To identify, describe, and assess potential donor sites for pedicled VBGs from occiput to T12 using a cadaver model and to describe important technical considerations for graft harvest and placement. A multidisciplinary team of plastic surgeons and neurosurgeons hypothesized that it is feasible to rotate a pedicled VBG from the occiput to T12 via a posterior approach. In 6 cadavers, 3 VBG donor sites were identified as anatomically feasible: occiput, scapula, and rib. Split- and full-thickness occipital VBGs were mobilized on a semispinalis pedicle. Occipital VBGs could be mobilized from occiput to T1 and span up to 4 levels. Scapular VBGs were mobilized on a subscapular pedicle and could be mobilized from occiput to T7 and span up to 8 levels. Rib VBGs were mobilized on subcostal pedicles and could be mobilized from C6 to T12. Ribs T2 to T4 and T11 and T12 could cover 2 levels, and ribs T5 to T10 could cover 3 levels. The first rib was anatomically unsuitable as a VBG due to its primarily ventral course. Pedicled VBGs can feasibly be applied to posterior spinal arthrodesis from occiput to T12. Patients at high risk for nonunion may benefit from this strategy.