Formation and distribution of the sural nerve based on nerve fascicle and nerve fiber analyses

Abstract

The formation and distribution of the sural nerve are presented on the basis of an investigation of 31 legs of Japanese cadavers using nerve fascicle and fiber analyses. Nerve fibers constituting the medial sural cutaneous nerve were designated as 'T', whereas those constituting the peroneal communicating branch were designated as 'F'. In 74.2% of cases (23/31), the T and F fibers joined each other in the leg, whereas in 9.7% of cases (3/31) they descended separately. In 16.1% of cases (5/31), the sural nerve was formed of only the T fibers. The sural nerve gave off lateral calcaneal branches and medial and lateral branches at the ankle. The lateral calcaneal branches always contained T fibers. The medial branches consisted of only T fibers, whereas most of the lateral branches consisted of only F fibers (71.0%; 22/31). In addition to the T and F fibers, P fibers, which derived from the superficial and deep peroneal nerves, formed the dorsal digital nerves. The P fibers were entirely supplied to the medial four and one-half toes. However, they were gradually replaced by the T and F fibers in the lateral direction. The 10th proper dorsal digital nerve consisted of T fibers only (38.7%; 12/31), of F fibers only (19.4%; 6/31) or of both T and F fibers (38.7%; 12/31). These findings suggest that the T fibers are essential nerve components for the skin and deep structures of the ankle and heel rather than the skin of the lateral side of the fifth toe. The designation of the medial sural cutaneous nerve should be avoided and only the T fibers are appropriate components for naming as the sural nerve.

Variations in sural nerve formation pattern and distribution on the dorsum of the foot

“…Moreover, in our results, 53.2% of the cases reached the third interdigital space (between the fourth and third toes) solely (type VI in Table 4) or in conjunction with branches of the superficial peroneal nerve (types III and V). We did not explore this issue, but some answers can be found in Sekiya et al (2006). The numbers in parentheses represent the frequency of the corresponding type.…”

Computer-assisted assessment of the histological structure of the human sural nerve

“…Literature analysis shows that previous researchers focused mainly on its anatomical variations [1,5,9,[14][15][16][17][18]. A limited number of studies concentrated on the histological analysis of the sural nerve [3,7,8,13].…”

“…Here, slightly lateral to the Achilles tendon, this nerve adheres to the lesser saphenous vein. Distally from this point the sural nerve runs between the lateral malleolus and the calcaneus and continues to the fifth toe [5,16].…”

“…The sciatic nerve at the level of the popliteal fossa divides into the tibial and common peroneal nerves. It has been determined that the sural nerve originates distally, in the place where the medial sural cutaneous nerve branches connect with the common peroneal nerve fibres [5,16].…”

Imaging of Peripheral Nerve Lesions in the Lower Limb

“…The contribution of the lateral sural cutaneous nerve to sensation was mainly to the skin on the lateral side of the big toe 15 and the proximal half of the calf. The classic description is that the proximal SN is formed by the union of the medial sural cutaneous nerve (MSCN) from the tibial nerve and the peroneal communicating branch (PCN) of the lateral sural cutaneous nerve from the CPN.…”