The previously unreported fusion of the extensor digitorum longus and the extensor hallucis longus: anatomical and clinical considerations.

BACKGROUND

Most of the anatomical variants in the anterior compartment of the leg is related with morphology of tendons and insertion points. The variants related with muscle bellies and their relations with surrounding structures are much less profusely described. We present a case of a unique fusion between the extensor hallucis longus and the extensor digitorum longus.

MATERIALS AND

METHODS

During a routine dissection of a female cadaver, an anomalous fusion between the extensor digitorum longus and the extensor hallucis longus was encountered. The finding was subsequently measured and photographed.

RESULTS

Both muscles had a common attachment to the fibula. This fusion extended distally beyond their common origin. The anatomy of the tendons, their insertions and relation to the fibularis tertius and tibialis anterior muscles was typical.

CONCLUSIONS

Many variants of the extensor hallucis longus and the extensor digitorum longus have been previously described however, most of them refer to their tendons. It is important to be aware of morphological variability of the muscles, even if they are not common finding. We hypothesize that this variant may predispose to more severe injuries and increased pain sensations.