Purpose: Isolated paralysis of the great toe long extensor is a rare complication of leg fractures. In certain patients, an erroneous diagnosis of compartment syndrome or muscle incarceration may be made.

Material and methods: We dissected ten fresh cadavers.

Results: The great toe long extensor was innervated by a branch of the deep fibular nerve which arose 15 cm from the talocrural joint space and directly in contact with the periosteum of the tibial shaft. In this localisation, the branch can be directly sectioned during trauma, reduction, or reaming.

Discussion: We had one patient aged 30 years with a fracture of the mid third of the leg who was treated by centromedullar nailing. Postoperatively, this patient developed isolated paralysis of the great toe long extensor. The isolated neurogenic origin of this paralysis was confirmed by electromyography.

Conclusion: This case is illustrative of direct injury of the great toe long extensor innervation, a cause which to our knowledge has not been previously described.