Topography of the common fibular nerve terminal division in human foetuses

Background: The progress of pediatric surgery and increasingly better diagnosis of fetal defects require detailed knowledge of human developmental anatomy. Precise knowledge of the anatomy of innervation of the lower extremities corresponds to this subject and is not only cognitive but also clinically important. The end of the common fibular nerve is superficially located in the area exposed to frequent injuries as well as in the area subject to possible surgical repair procedures. Materials and methods: The analysis was carried out on 200 human foetuses aged from the 113 th day to 222 nd day of foetal life. The study material is a part of local fetal collection. The study incorporated the following methods: anthropological, preparational and image acquisition which was acquired with the use of high-resolution digital camera. Statistical analysis was carried out with the use of STATISTICA package. Results: Based on the research results the new typology of the examined nerve was determined. The head of the fibula was the criterion: (i) high division – above the head of the fibula (1%); (ii) intermediate division – at the height of the head of the fibula (34%); (iii) low division – below the head of the fibula (65%). The mathematical analysis did not reveal statistically significant bilateral and gender differences. Moreover the additional branch was observed in 30% of fetuses, regardless of age class. This branch occurred in 50% of cases in both sides of the fetus. This nerve was defined as the accessory fibular nerve (nervus fibularis/peroneus accessorius). Conclusions: The created unique typology of the terminal division of common fibular nerve is an important supplement to the anatomical knowledge and at the same time, due to the peripheral and superficial location of the described structures, it has a relatively high clinical significance.