Superficial fibular nerve variations of fascial piercing: A meta-analysis and clinical consideration

The superficial fibular (peroneal) nerve (SFN) is one of the successive branches of the common fibular (peroneal) nerve and goes on to bifurcate into the medial dorsal cutaneous (MDN) and intermediate dorsal cutaneous (IDN) nerves. The SFN is a main contributor to sensory innervation of the foot and lower leg. It varies widely in its penetrance of the deep (crural) fascia, and differences in its subsequent course can result in iatrogenic injuries. Articles on the prevalence of this anatomical variation were identified by a comprehensive database search. The data collected were extracted and pooled into a meta-analysis. A total of 14 articles (n=665 lower limbs) were included on the meta-analysis of SFN variations in fascial piercing. The normal Type 1 variation, where the SFN pierces the deep fascia as a single entity and later bifurcates into the MDN and IDN, had a pooled prevalence of 82.7% (95%CI: 74.0-89.4). The Type 2 variant, where the SFN bifurcates early and then pierces the fascial layer separately as the MDN and IDN, had a pooled prevalence of 15.6% (95%CI: 8.9-23.6). Type 3, when the SFN penetrates the deep fascia and courses similar to the MDN with absent IDN was noted in 1.8% (95%CI: 0.0-4.9) of cases. A substantial portion of the population has a pattern of SFN piercing that deviates from the normal Type 1 anatomy. It is recommended that possible SFN variants in patients should be addressed thoroughly to help prevent iatrogenic injuries and postoperative complications. Clin. Anat. 30:120-125, 2017. (c) 2016 Wiley Periodicals, Inc.