Femoral nerve entrapment: A new insight

Abstract

Compression of the femoral nerve in the iliac fossa has been reported as a consequence of several pathologies, but never as a result of muscular compression. Aberrant slips of iliacus, however, have occasionally been reported to cover or split the femoral nerve. This study aimed to assess such variations as potential factors in femoral nerve compression. A large and homogeneous sample of 121 embalmed cadavers (242 specimens) was studied. Statistical comparisons were made using the chi-squared test. Muscular slips from iliacus and psoas, piercing or covering the femoral nerve, were found in 19 specimens (7.9%). No significant differences by sex or side were found. The more frequent variation was piercing of the femoral nerve by a muscular slip (17 specimens, 7.0%). The nerve then entered the thigh as one or more branches. The less frequent variation found was a muscular slip or sheet covering the femoral nerve as it lay on iliacus (2 specimens, 0.8%). Each disposition may be a potential risk for nerve entrapment.

Split Femoral Nerve Due to Psoas Tertius Muscle: A Review with Other Cases of Variant Muscles Traversing the Femoral Nerve

“…Multiple studies have reported variant slips of the psoas and iliacus muscles, which may split the femoral nerve causing a potential risk for nerve entrapment [6]. In a large study of 121 cadavers, Vasquez, et al reported variations of iliacus and psoas muscles piercing the femoral nerve with piercing of the femoral nerve by a muscular slip, or a muscular slip/sheet covering the femoral nerve as it lay on the iliacus in 19 specimens (7.9%) [7]. Several entities exist which may cause femoral neuropathy and entrapment of the nerve is most likely to occur immediately distal to the inguinal ligament owing to the lack of anatomic protection [8].…”

Ultrasound Guided Detection of an Aberrant Femoral Nerve in a Pediatric Patient

“…Most of these variations consisted of bifurcation of the femoral nerve into two or three slips, separated by psoas major muscle fibers before they rejoined prior to the femoral nerve exiting from the pelvic cavity. In another cadaveric study, muscular slips from iliacus and psoas were found piercing or covering the femoral nerve in 7.9% of the specimens [4]. An anomalous higher branching pattern of the femoral nerve above the inguinal ligament has also been reported [5,6].…”

Anomaly of Flexor Digitorum Superficialis Penetrating Through the Median Nerve: Case Report

“…17,18 Various anomalies of median nerve anatomy in the wrist have been described in the literature 2,12,19 -28 and are frequently encountered in clinical practice.…”