Electrodiagnostically confirmed posttraumatic neuropathy and associated clinical exam findings with lisfranc injury.

BACKGROUND

Patients with a Lisfranc injury often complain of persistent pain radiating from the Lisfranc joint up or down the first dorsal web space, accompanied by decreased sensation. We hypothesized that these symptoms were related to a posttraumatic neuropathy of the terminal medial branch of deep fibular (peroneal) nerve (MBDFN) and that by recognizing this symptom an earlier diagnosis of Lisfranc injury may be possible.

METHODS

Twelve patients with diagnosis of subtle unilateral Lisfranc injury, confirmed by standing X-ray, CT, or bone scan, were enrolled. Standardized antidromic sensory nerve conduction studies of MBDFN were performed bilaterally within 2 months postinjury and prior to surgical intervention. The contralateral, normal side was used as a control. All patients were tested for decreased 2-point discrimination in the first dorsal web space on both lower extremities.

RESULTS

Sensory nerve action potential of the MBDFN was absent, with decreased 2-point discrimination on the injured side in all patients.

CONCLUSION

Lisfranc injuries were associated with a posttraumatic neuropathy of the MBDFN and decreased 2-point discrimination in the first dorsal web space. The finding of altered sensation in the first dorsal web space may help the practitioner to earlier diagnosis of a Lisfranc injury.

LEVEL OF EVIDENCE: Level III, case control study.