Objective

Beside the posterior leg compartment, spasticity of the hemiplegic patient can involve other muscle groups in the leg. Spasticity of the lateral compartment is responsible of a vertical clonus that may be confused with the clonus of the triceps surae (long fibular) or a transverse clonus (short fibular), and by the liveliness of the tendon reflex when striking their tendon. Beside recurrent botulinum toxin injections, this spasticity may be treated by a hyponeurotisation by partial section of the branches of the superficial fibular nerve to the muscle(s) concerned. Its technique has never been described.

Material/patients and methods

Twelve legs of formalin corpses have been dissected. The number of branches to PL and PB, their level of emergence from the common and deep fibular nerves, and their entry point into the muscle have been measured from the lateral femoral-tibial articular space (LTF).

Results

There was always a common trunk to the EDL and the EHL, arisen on average at 10.3 cm (8.2–13.6) from the LTF line. Six times out of 10 in addition to this common one (3), two (2) or three (1) additional branches to the EDL, arisen between 4.6 and 12 cm downstream the LTF line. Six times out of 10 in addition to this common trunk existed one (4) or two (2) additional branches to the EHL, arisen between 13 and 26 cm downstream the LTF line.

Discussion–conclusion

This first study allow establishing the surgical technique of the hyponeurotisation of PL and PB muscles. The first results are presented.