Bipedicle paraspinous muscle flaps for spinal wound closure: An anatomic and clinical study

The purpose of this study was to evaluate the vascular anatomy of the paras pinous muscles and review their clinical use as bipedicled flaps in spinal wound closure. Anatomically, through cadaver dissections, lead oxide inject ions, and radiographic imaging, the blood supply to the paraspinous muscles was determined. Clinically, 29 consecutive patients treated with spinal wo unds and exposed bone or hardware were reviewed retrospectively. Of these p atients, 19 underwent closure in delayed primary fashion, whereas 10 were r eferred to plastic surgery for reconstruction because of the complex nature of their wounds. The cadaver study demonstrated the paraspinous muscles to possess a segmental arterial supply through medial and lateral perforators . Division of the medial perforators allowed for medial advancement of the muscles. Lead oxide injection of the lateral perforators demonstrated adequ ate medial muscle perfusion with ligation of the medial perforators. Ten of the 29 patients (six women, four men, 32 to 62 years of age) were reconstr ucted with paraspinous (eight), latissimus (one),and trapezius (one) muscle flaps. A higher complication rate was found in wounds closed in delayed pr imary fashion (13 of 19 patients, 68 percent) than those reconstructed with muscle flaps (2 of 10 patients, 20 percent) (p = 0.021). Follow-up of the muscle flap reconstructed patients averaged 12 months (range, 3 to 27 month s). Ca daver muscle injections predicted and clinical cases confirmed that the paraspinous muscles can be raised on lateral perforators and advanced m edially to close lumbar spine wounds reliably with fewer complications.