Protective mechanisms of the common fibular nerve in and around the fibular tunnel: A new concept

Abstract

The most frequent site at which the common fibular nerve is affected by compression, trauma, traction, masses, and surgery is within and around the fibular tunnel. The aim of this study was to determine whether there were protective mechanisms at this site that guard against compression of the nerve. Twenty-six lower limbs of 13 preserved adult cadavers (11 males and two females) were used. Proximal to the entrance of the tunnel, three anatomical configurations seemed to afford the required protection for the nerve: reinforcement of the deep fascia; tethering of the common fibular nerve to both the tendon of the biceps femoris and the reinforced fascia; and the particular arrangement of the deep fascia, fibular head, and soleus and gastrocnemius muscles. At the entrance of the tunnel, contraction of the first segment of fibularis longus muscle could afford the required protection. In the tunnel, contraction of the second and third segments of fibularis longus muscle could guard against compression of the nerve. The tough fascia on the surface of fibularis longus muscle and the fascial band within it, which have long been accused of compression of the nerve, may actually be elements of the protective mechanisms. We conclude that there are innate, anatomical protective mechanisms which should be taken into consideration when decompressing the common fibular nerve. To preserve these mechanisms whenever possible, the technique should be planned and varied according to the underlying etiology.

Paresthesia and hypesthesia in the dorsum of the foot as the presenting complaints of a ganglion cyst of the foot

“…In addition, other diagnostic possibilities would be L5 root pathology, and a lesion of the common fibular nerve. This last nerve may be affected in several conditions, namely posttraumatic intraneural hemorrhage, compression near the tendinous arch located at the fibular insertion of the fibular longus muscle, compression by a ganglion cyst in the vicinity of the knee or even a nerve sheath tumor (Rawal et al, 2004;Spinner et al, 2006;Ji et al, 2007;El Gharbawy et al, 2009).…”

Evaluation of the neuromuscular compartments in the peroneus longus muscle through electrical stimulation and accelerometry

“…This finding corresponds to the anatomical position of the S-NMC, which is located above the AI-NMC and PI-NMC. Upon stimulation, the S-NMC exerts traction through via the connective tissues that are connected to the underlying compartments (intramuscular septum) 12 . These compartments accelerate the foot along the X-and Y-axes with comparable intensity.…”

“…This organization occurs at the innervation level, particularly at the union of a nerve with a muscle. An example of this structure is the peroneus longus muscle, in which the presence of multiple motor branches has been detected, with each of them innervating a subdivision or neuromuscular compartment (NMC), specifically, the superior (S-NMC), anteroinferior (AI-NMC), and posteroinferior (PI-NMC) 12,13 . The projection of these subdivisions to the surface of the skin facilitates the localization of three motor points 13 .…”