Abstract
Background Foot drop is the common endpoint for a diverse set of nerve injuries, affecting over
128,000 in the United States each year. The level of injury, finite pace of regeneration,
and/ exponential decay in the percentage of motor end-plates reinnervated over time
may explain the limited success with natural recovery. Past nerve techniques have
also been met with limited success.
Methods This narrative review explores why past nerve techniques have failed to correct foot
drop.
Results Previously described nerve transfer techniques suffer from incompletely balancing
the foot and ankle, poor donor-target nerve synergy, and/or not effectively bypassing
the wide and oftentimes underappreciated zone of injury. For maximal stability, one
should look to balance the foot in both dorsiflexion and eversion. Detailed descriptions
and illustrations of the branching anatomy for the peroneal and tibial nerves are
provided, with specific application to nerve transfer reconstruction.
Conclusion Based on an understanding of why past nerve techniques have failed to correct foot
drop, a set of surgical principles can be codified to optimize functional outcomes.
A surgical technique should be versatile enough to address foot drop from any of the
three common pathways of injury (lumbar spine, sciatic nerve, and common peroneal
nerve). With increasing familiarity using this once poorly understood anatomical region,
limitations with past nerve transfer techniques may be overcome.
Keywords
foot drop - sciatic nerve palsy - common peroneal nerve palsy - nerve transfer - peroneal
nerve palsy - tibial nerves
