The sensate fibula osteocutaneous flap: neurosomal anatomy.

BACKGROUND: Rapid return of oral sensation enhances quality of life following oromandibular reconstruction. For predictable reinnervation of flaps, a detailed knowledge of their nerve supply is required. This study was designed to investigate the cutaneous nerve supply of the fibula osteocutaneous flap. METHODS: We dissected thirty-seven fresh cadaveric specimens to better understand the cutaneous innervation of the typical fibula flap that would be used in oromandibular reconstruction. In addition, ten volunteers were enlisted for nerve blocks testing the cutaneous innervation of the lateral aspect of the lower leg. RESULTS: The lateral sural cutaneous nerve (LSCN) is generally considered to be sole cutaneous innervation to the lateral aspect of the lower leg; however, our analysis of the cadaveric specimens revealed dual innervation to this region. We identified a previously unnamed distal branch of the superficial peroneal nerve, which we have termed the recurrent superficial peroneal nerve (RSPN). Given the cadaveric findings, both the LSCN and the RSPN were tested using sequential nerve blocks in 10 volunteers. An overlapping pattern of innervation was demonstrated. CONCLUSIONS: The lateral aspect of the lower leg has an overlapping innervation from the LSCN and the newly described RSPN. The overlap zone lies in the region of the skin paddle of the fibula flap. The exact position of the neurosomal overlap zone (N.O.Z.E.) may be an important factor in reestablishing sensation in the fibula's skin paddle following free tissue transfer.

The sensate fibular osteoneurocutaneous flap in oromandibular reconstruction: clinical outcomes in 31 cases.

Thirty-one patients requiring composite mandibular resection were reconstructed with sensate fibula osteocutaneous flaps. Preoperatively, all patients underwent lower extremity sensory testing at the location of the proposed flap site. Intraoperatively, either the Lateral Sural Cutaneous Nerve (LSCN) or the Recurrent Superficial Peroneal Nerve (RSPN) was chosen as donor. It was then joined to either the lingual or the greater auricular nerve. Both end-to-end and end-to-side neurorrhaphies were used. At least six months postoperatively, the intraoral flaps were tested for sensory function. Twenty-eight patients achieved sensory return, including hot/cold and pinprick sensation. Both the LSCN and RSPN groups demonstrated improved two-point discrimination in static and moving studies. Better results were obtained when the lingual rather than the greater auricular nerve was the recipient. Only three patients underwent end-to-side repair, with improved two-point discrimination in two patients. The average follow-up for all patients was 11.7 months. The most dramatic return of sensory function was seen in the end-to-end lingual nerve neurorrhaphies, followed by end-to-side lingual nerve neurorrhaphies. Of the five repairs using the greater auricular nerve, only three demonstrated any measurable postoperative sensory return. Functional outcomes of postoperative patients were measured via analysis of speech, type of food consumption, and oral continence. The majority of patients exhibited normal or easily intelligible speech, was able to consume a soft food or normal diet, and could maintain normal to manageable oral continence. A subset of patients enrolled in the study went on to pursue dental rehabilitation.