Variations in Innervation Pattern to Dorsum of Foot by Medial Dorsal Cutaneous Nerve, Intermediate Dorsal Cutaneous Nerve, Lateral Dorsal Cutaneous Nerve with Surgical and Clinical Correlations: A Cadaveric Dissection Based Study

The complete reconstruction of any soft tissue defect includes even the sensory recovery which is very significant aspect pertaining to prognosis. Superficial nerves in the vicinity of the vascular axis can be considered as vascular relays and neuroskin grafts can be constructed on them. Variations in innervation to various part of the dorsum of the foot by this nerve should be kept in mind while making these grafts. Authors dissected 50 formalinized cadaveric feet and studied normal anatomy and variations in origin, course, branching pattern, communications, and any other variations in medial, intermediate and lateral dorsal cutaneous nerve. The intermediate dorsal cutaneous nerve was innervating larger area of the skin around 3rd and 4th web spaces in 60% of cadaveric feet. The 2nd web space was innervated by medial dorsal cutaneous nerve in 92% of cadaveric feet. In 52% of cadaveric feet communicating branches were found between intermediate dorsal cutaneous nerve and lateral dorsal cutaneous nerve. In 63% cadaveric feet communicating branches were found between medial dorsal cutaneous nerve and branch of deep peroneal nerve to 2nd web space. The mean distance between lateral malleolus and intermediate dorsal cutaneous nerve was 4.05cm. These all observations can provide anatomical basis at the time of preparing medial dorsal cutaneous nerve flaps and intermediate dorsal cutaneous nerve flaps and also can minimize morbidity at donor site.

Distribución de los nervios cutáneo dorsal medial y cutáneo dorsal intermedio en el hombre / Distribution of the medial dorsal cutaneous and intermediate dorsal cutaneous nerves in man

Gran parte de la inervación sensitiva del dorso del pie está dada por los ramos cutáneos del nervio fibular superficial, los nervios cutáneo dorsal medial (NCDM) y cutáneo dorsal intermedio (NCDI). El objetivo de esta investigación fue estudiar las divisiones de los NCDM y NCDI a nivel del tercio distal de la pierna y el dorso del pie, para contribuir con conocimientos específicos al abordaje quirúrgico de la región. Disecamos 19 piernas y pies en cadáveres de individuos adultos, masculinos, correspondientes al Departamento de Morfología de la Universidad de La Frontera de Temuco. Se dividió el dorso del pie, en tercios anterior, medio, posterior y luego, las divisiones observadas se padronizaron. La división de los NCDM y NCDI, en ramos medial y lateral, se observó en el tercio distal de la pierna, en un 47,4 por ciento y 52,6 por ciento respectivamente. La división del ramo medial de los NCDM y NCDI en ramos terminales, se observó en el tercio posterior del dorso del pie (42,2 por ciento) y en el tercio distal de la pierna (21,1 por ciento), respectivamente. La división del ramo lateral de los NCDM y NCDI en ramos terminales, se observó en el tercio posterior del dorso del pie (21,1 por ciento) y en el tercio anterior del dorso del pie (15,8 por ciento) respectivamente. La división de los ramos terminales del ramo medial de los NCDM y NCDI en nervios digitales dorsales, se observó en el tercio medio del dorso del pie en un 21,1 por ciento y 15,6 por ciento respectivamente. La división de los ramos terminales del ramo lateral de los NCDM y NCDI en nervios digitales dorsales, se observó en el tercio anterior del dorso del pie en un 15,8 por ciento, para ambos. Estos datos, pueden servir de referencia durante los procedimientos quirúrgicos realizados en la región, evitando lesiones iatrogénicas del área.

The sensory innervation of the dorsum of the foot is given by the cutaneous branches of the superficial fibular nerve, the medial dorsal cutaneous (MDCn) and intermediate dorsal cutaneous (IDCn) nerves. The aim of this research was to study the divisions of the MDCn and IDCn at the distal third of the leg and dorsum of the foot, to contribute expertise for the surgical approach in the región. Nineteen legs and feet of adult male cadavers, of the Department of Morphology, Universidad de La Frontera in Temuco, were dissected. We divided the dorsum of the foot in anterior, middle and posterior third, then the divisions were observed and patterned. The division of the MDCn and IDCn in medial and lateral branches was observed in the distal third of the leg, 47.4 percent and 52.6 percent respectively. The division of the medial branch of the MDCn and IDCn in terminal branches, was observed in the posterior third of the dorsum of the foot (42.2 percent) and in the distal third of the leg (21.1 percent), respectively. The division of the lateral branch of the MDCn and IDCn in terminal branches, was observed in the posterior third of the dorsum of the foot (21.1 percent) and in the anterior third of the dorsum of the foot (15.8 percent) respectively. The division of the terminal branches of the medial branch of the MDCn and IDCn in dorsal digital nerves was observed in the middle third of the dorsum of the foot at 21.1 percent and 15.6 percent respectively. The division of the terminal branches of the lateral branch of the MDCn and IDCn in dorsal digital nerves was observed in the anterior third of the dorsum of the foot at 15.8 percent for both. These data may serve as a reference during surgical procedures performed in the region, avoiding iatrogenic injuries of the area.