Morphological Variation in the Communicating Branch between the Lateral and Medial Plantar Nerves

Abstract

Studies investigating the presence of a communicating branch between the lateral and medial plantar nerves (LMCB) have found widely differing occurrence rates. In our study on human cadavers of Caucasian descent (ages 50‐103), feet were dissected to ascertain the presence, dimensions, and course trajectory of the LMCB. The LMCB was present in 77.3% of the feet, with most coursing in the medial oblique direction (58.8% of anastomoses). The medial oblique coursings started at a proximal location on the lateral plantar nerve, lateral to quadratus plantae, and ended distally on a branch of the medial plantar nerve between flexor digitorum brevis tendons to digits 3 and 4. Transverse and lateral oblique coursings were also found, constituting 17.7% and 23.5% of anastomoses each. The average length, width, and thickness of the LMCB were 11.6 mm, 1.1 mm, and 0.5 mm respectively. A single instance of two parallel running branches was also found, both coursing in the lateral oblique direction 14.0 mm apart, as was a branch that bifurcated laterally before anastomosing. A single branch originating from the deep branch of the lateral plantar nerve superior to quadratus plantae was also found. These results suggest a more frequent occurrence and a more widely varying morphology than has been previously described. The prevalence and position of this anastomotic nerve is important in planning podiatric surgical approaches, and invaluable in characterizing morphological variations in peripheral nerve coursings, networks, and anastomoses.