Determination and classification of cutaneous innervation of the dorsum of the foot in foetal cadavers.

BACKGROUND: The aim of this study is to determine cutaneous innervation of the dorsum of the foot on foetal cadavers.

MATERIALS AND METHODS: In this study. 200 limbs from 100 embalmed foetuses (54 males and 46 females) were studied in Anatomy Laboratory. Contributions of medial, lateral and intermediate dorsal cutaneous nerves (MDCN, LDCN and IDCN) of the foot were identified.

RESULTS: Cutaneous innervation of the dorsum of the foot was classified into five types. Type I (75%) where MDCN innervated medial border of the foot and second interdigital cleft; IDCN innervated third, fourth and fifth interdigital clefts; and LDCN innervated the lateral border of the foot. Type II (21%) where MDCN innervated medial border of the foot, second and third interdigital clefts; IDCN innervated fourth and fifth interdigital clefts; and LDCN innervated the lateral border of the foot. Type III (1.5%) where saphenous nerve innervated medial border of the foot; MDCN innervated second and third interdigital clefts; IDCN innervated fourth and fifth interdigital clefts; and LDCN innervated the lateral border of the foot. Type IV (1.5%) was similar to type I, with an extra connection between the MDCN and IDCN on the dorsum of the foot. Type V (1%) where superficial fibular nerve innervated medial border of the foot, and second, third and fourth interdigital clefts; and sural nerve innervated fifth interdigital cleft and lateral border of the foot.

CONCLUSIONS: The present study provides a new classification for the cutaneous innervation of the dorsum of the foot.