Anatomical feasibility of performing a nerve transfer from the femoral branch to bilateral pelvic nerves in a cadaver: a potential method to restore bladder function following proximal spinal cord injury.

OBJECT: Nerve transfers are an effective means of restoring control to paralyzed somatic muscle groups and have recently been shown to be effective in denervated detrusor muscle in a canine model. A cadaveric study was performed to examine the anatomical feasibility of transferring femoral muscular nerve branches to vesical branches of the pelvic nerve as a method of potentially restoring innervation to control the detrusor muscle in humans.
METHODS: Twenty cadavers were dissected bilaterally to expose pelvic and femoral muscular nerve branches. Ease of access and ability to transfer the nerves were assessed, as were nerve cross-sectional areas.
RESULTS: The pelvic nerve was accessed at the base of the bladder, inferior to the ureter, and accompanied by inferior vesical vessels. Muscular branches of the femoral nerve to the vastus medialis and intermedius muscles (L-3 and L-4 origins) were followed distally for 17.4 ± 0.8 cm. Two muscle branches were split from the femoral nerve trunk, and tunneled inferior to the inguinal ligament. One branch was moved medially toward the base of the bladder and linked to the ipsilateral pelvic nerve. The second branch was tunneled superior to the bladder and linked to the contralateral pelvic nerve. The cross-sectional area of the pelvic nerve vesical branch was 2.60 ± 0.169 mm(2) (mean ± SEM), and the femoral nerve branch at the suggested transection site was 4.40 ± 0.41 mm2.
CONCLUSIONS: Use of femoral nerve muscular branches from the vastus medialis and intermedius muscles for heterotopic nerve transfer of bilateral pelvic nerves is surgically feasible, based on anatomical location and cross-sectional areas.