Abstract:

Objective　This study was designed to investigate the anatomic foundation for the transoral approach with mandibulutomy and mandibuloglossotomy.　Methods　Transoral approach with mandubulutomy and mandibuloglossotomy were simulated in 6 fresh cadavers to cervical spinal cord; the cephalic and caudal limits of exposure  and the distances between the vertebral artery(VA) of each side to the midline and the vertical depth between the VA of each side to the fore-teeth of the two approaches were measured. Furthermore, the exploratory operational range and reconstructive operational range were described. Results　The exposure angle of mandibulotomy and mandibuloglossotomy were 63.67°±3.50°and 74.14°±1.47°, respectively.The widest EOR of mandibulotomy and mandibuloglossotomy were the lower third of the clivus to the upper edge of C5 and the lower third of the clivus to the upper edge of C6, respectively.The widest ROR of mandibulotomy and mandibuloglossotomy were the lower half of axis to the upper edge of C5 and the lower half of axis to the upper edge of C6, respectively. The distance between the vertebral artery(VA) of each side to the midline is  (16.88±0.75)mm at C2/3, (16.48±1.47)mm at C3/4 and (16.30±1.09)mm at C4/5, respectively. Furthermore, the vertical depth between the VA of each side to the fore-teeth of the two approaches was (96.44±3.59)mm at C2/3,(97.94±4.51)mm at C3/4 and (99.83±4.77)mm at C4/5, respectively. Conclusions　The transoral approach with mandibulotomy and mandibuloglossotomy is safe and effective in dealing with patients with limitation of mouth opening and long segmental ventral decompression of the cervical spine; However,whether glossotomy is performed or not depends on the particular range of the surgery.

Key words: Surgical approach, Transoral approach, Upper cervical spine, Mandibular, Applied anatomy