Anatomy and evaluation of the lumbosacral plexus.

Although not as common as brachial plexopathies, lumbosacral plexopathies do occasionally occur. Most plexopathies are due to masses that compress or infiltrate the pelvis, traction on the plexus itself from dislocation of the hemipelvis, or ischemia. Diagnosis and evaluation of the lumbosacral plexus may be made using electrodiagnostic testing, MR imaging, or CT scans, in addition to the patient's history, thorough physical examination, and knowledge of the anatomy of the plexus and its associated anatomical structures.