Imaging on the painful and compressed nerve: lower extremity

Area of Science:

• Radiology and Imaging
• Neurology
• Orthopedics

Background:

• Lower extremity entrapment neuropathies are frequently underdiagnosed.
• Clinical examination and electrophysiological tests have limitations in diagnosing these conditions.

Purpose of the Study:

• To review the imaging features of compressive neuropathies of the lumbosacral plexus and its branches.
• To highlight the diagnostic value of advanced imaging techniques in evaluating these neuropathies.

Main Methods:

• Review of MR neurography and high-resolution ultrasonography (US) findings.
• Focus on imaging characteristics of specific nerves: femoral, obturator, sciatic, common peroneal, and tibial.
• Discussion of key conditions: meralgia paraesthetica, piriformis syndrome, tarsal tunnel syndrome.

Main Results:

• Advanced imaging enables precise visualization of nerves and surrounding structures.
• Identified imaging findings include nerve thickening, T2 hypersignal, fascicular changes, and muscle denervation.
• Detection of structural causes like anatomical variations, fibrous bands, and space-occupying lesions is facilitated.

Conclusions:

• MR neurography and US significantly improve the evaluation and diagnosis of lower extremity entrapment neuropathies.
• These modalities are crucial for early diagnosis, guiding treatment, and enhancing patient outcomes.
• Accurate diagnosis relies on recognizing specific imaging features and associated structural abnormalities.