Bilateral sagittal split mandibular osteotomies as an adjunct to the transoral approach to the anterior craniovertebral junction - Technical note

Transoral approaches are used to expose the craniovertebral junction anteri orly. In patients in whom there is limited mandibular excursion, the placem ent of retractors and/or surgical instruments is difficult, and midline "st airstep split mandibulotomy" has been advocated as an adjunctive procedure. Although effective, this approach requires external splitting of the lip a s well as median glossotomy or a lateral mucosal incision. The purpose of t his study was to show that bilateral sagittal split mandibular osteotomies (BSSMOs), which are used in orthognathic surgery, represent a safer and mor e effective alternative to the stairstep split mandibulotomy when performed as an adjunct to the transoral approach because all incisions are intraora l and the plane of retraction is rostrocaudal instead of lateral. Hospital records and radiographic files of four patients who underwent BSSM O/transoral approach for odontoidectomy between 1994 and 1997 were reviewed retrospectively. There were three women and one boy (mean age 37.8 years, range 11-68 years). Predisposing conditions included rheumatoid arthritis ( two patients), Klippel-Feil syndrome (one patient), and congenital occipito cervical instability (one patient). Jaw mobility was limited in all patient s. In addition, one patient had macroglossia, another micrognathia, and ano ther retrognathia. The BSSMO provided excellent exposure for resection of the odontoid process , as verified on follow-up magnetic resonance imaging or computerized tomog raphy studies obtained in all patients. All mandibles were rigidly fixed by placing anterior mandibular border titanium plates and unicortical screws, and there was no incidence of nonunion or of lingual or inferior alveolar nerve injuries. The mean follow-up period was 26 months. The BSSMO is an excellent, less invasive adjunct to the transoral approach in patients with limited jaw mobility.