Brian P. Jacob, David C. Chen, Bruce Ramshaw, Shirin Towfigh (eds.) - The SAGES Manual of Groin Pain-Springer International Publishing (2016)

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R. Álvarez
intentionally or incidentally, or due to entrapment of the nerve by a
suture or penetrated when fixating with tacks. This type of pain is the
most persistent and severe in intensity.
It is noteworthy that after more than 10 years evaluating patients with
chronic postoperative pain, we have not had a single case of lateral femoral
cutaneous nerve involvement. The most frequently affected nerve by
both open and laparoscopic approaches has been the ilioinguinal nerve,
followed by the genital branch in the open technique, especially in
patients in whom plugs were placed in the internal ring where this branch
emerges, or when the round ligament was severed. The femoral branch
of the genitofemoral nerve was involved mainly in the laparoscopic
approach [ 9 ]. We believe that the mechanism of injury of the femoral
branch is caused by traction, pulling, or rupture of this structure when
dissecting near to the iliac vessels. This is probably the reason why most
of these patients improve with conservative management, since the
mechanism of injury is not entrapment. Even so, the recommended treatment
for patients with persistent pain involving femoral branch dermatome
after 3 months is the lumboscopic approach and truncal genitofemoral
nerve resection [ 10 , 11 ]. The surgical management often involves
removal of the mesh [ 12 , 13 ] and tacks with neuropathy addressed with
selective neurectomy [ 8 , 9 , 13 ], triple neurectomy [ 14 , 15 ], or extended
or quadruple truncal neurectomy [ 10 , 11 ].
Introduction
Dermatome Mapping
Clinical evaluation of the dermatomes involved with each nerve trunk
has been a routine part of our general medical practice due to our academic
training in routine neurological assessment; therefore, to consider
dermatome mapping in a comprehensive evaluation of the patient with
chronic postoperative groin pain is of utmost significance when addressing
such patients. For this reason, in 1998 we developed and implemented
the dermatome mapping test (DMT) as an integral tool in the evaluation
of our patients [ 11 , 15 ]. Since then, DMT has shown us a high sensitivity
when matching mapped results with the surgical findings. More importantly,
it has demonstrated high sensitivity with histological results [ 11 ]
and postsurgical evaluation and outcomes (see Clinical Cases below).