Articulating external fixation to overcome nerve gaps in lower extremity trauma.

This report describes the use of articulating external fixation in patients with lower extremity trauma with segmental nerve defects. Four patients who would otherwise require nerve grafting underwent application of an articulated external fixator, allowing optimal positioning for end-to-end, tension-free nerve repair followed by gradual lengthening. After three weeks of immobilization, the fixator was gradually advanced through the arc of the hinge. At an average follow-up of 44 months, motor function testing revealed gastroc-soleus function in all cases with a median motor grade of M4. Sensory function testing with Semmes-Weinstein monofilaments demonstrated protective plantar sensation in all cases with a median monofilament size of 3.84 on the injured limb compared with 3.22 on the contralateral side. This series of patients demonstrates that joint positioning through external fixation may be used safely and effectively to facilitate primary neurorrhaphy and subsequent limb salvage.