Cubital tunnel

Cause, clinical and ultrasound findings

• Compression of the ulnar nerve at the level of the elbow is due to anatomy (thickened Osborne ligament, accessory muscles such as anconeus epitrochlearis), systematic conditions (diabetes, pregnancy, etc.) and space-occupying lesions (ganglia, etc.).

• Numbness and burning pain in the ring and little fingers may be noted, along with motor deficit and wasting of hypothenar muscles (long-standing cases).

• Findings include an abrupt notch at the level of pressure, proximal swelling (cross-sectional area >8 mm ² ), distal flattening, hypoechoic appearance and wasting of the hypothenar echostructure. Occasionally, neovascularity in the nerve is noted.