Variations in the Origin of the Medial Calcaneal Nerve

Abstract

Previous anatomic studies of the medial heel region were done on embalmed human cadavers. Here, the innervation of the medial heel region was studied by dissecting living tissue with the use of 3.5-power loupe magnification during decompression of the medial ankle for tarsal tunnel syndrome in 85 feet. The medial heel was found to be innervated by just one medial calcaneal nerve in 37% of the feet, by two medial calcaneal nerves in 41%, by three medial calcaneal nerves in 19%, and by four medial calcaneal nerves in 3%. An origin for a medial calcaneal nerve from the medial plantar nerve was found in 46% of the feet. This nerve most often innervates the skin of the posteromedial arch, where it is at risk for injury during calcaneal spur removal or plantar fasciotomy. Knowledge of the variations in location of the medial calcaneal nerves may prevent neuroma formation during surgery and provide insight into the variability of heel symptoms associated with tarsal tunnel syndrome.

The “safe zone” in medial percutaneous calcaneal pin placement

“…The commonest variation in this study consisted of a single branch arising from the TN (16%) followed by the one arising from the LPN (14%). A MCN consisting of two independent branches, one arising before the bifurcation of the TN and the other from the MPN, was found in 13% of the cases (Dellon et al, 2002). Recently, Govsa et al (2006) corroborated the findings from all the above studies and found the MCN consisting of one to four independent branches, the commonest (5/ 25) being two, one arising before the bifurcation of the TN and the other from the MPN, similar to our findings.…”

“…Recently, more variations in the number of independent MCN branches have been presented. Dellon et al (2002), in the operating notes of 85 tarsal tunnel decompressions, found up to four major different MCN branches having variable origin either from the TN or from the LPN or MPN. The commonest variation in this study consisted of a single branch arising from the TN (16%) followed by the one arising from the LPN (14%).…”

“…There are multiple variations in the origins of the medial calcaneal nerve (MCN) (Havel et al, 1988;Didia and Horsefall, 1990;Davis and Schon, 1995;Park and Del Toro, 1995;Louisia and Masquelet, 1999;Dellon et al, 2002;Govsa et al, 2006). Govsa et al (2006) recently described 11 different variations, the commonest being two independent MCN branches, one arising early from the lateral plantar nerve and the other from the medial plantar nerve, adding to results from previous studies (Havel et al, 1988;Didia and Horsefall, 1990;Davis and Schon, 1995;Park and Del Toro, 1995;Louisia and Masquelet, 1999).…”

Considérations sur le syndrome du canal tarsien postéromédial et les formes apparentées (lésions du nerf tibial et de ses branches)

“…En conséquence, la seule observation d'une irritation d'une ou deux branches du nerf tibial ne Les variations anatomiques accentuent cette difficulté que rencontre l'examen clinique. La présence d'un seul nerf calcanéen médial est observée dans 37 % des cas, de deux nerfs (41 %), de trois nerfs (19 %) et même de quatre nerfs (3 %) [1,3].…”

Technique for determining when plantar heel pain can be neural in origin

“…Virtually every combination of innervation was identified, including patients with four separate nerves, and a nerve, present in about 50% of the patients that arose from the medial plantar nerve, crossed the vessels and then went through the abductor fascia to innervate the skin in the region of the typical DeVries incision for the medial plantar fasciotomy. 4 The nerve, frequently described as ''Baxter's nerve,'' [5][6][7] must be understood in the context of a nerve that innervates the periosteum of the medial calcaneal tubercle, and not the skin. This nerve will arise from a motor branch of the lateral plantar nerve, but as is clear from the wide variation in innervation pattern described above, this nerve often may be the second or third branch of the lateral plantar nerve.…”