Presentation
Numbness and tingling of the right 4th and 5th fingers for the last few days. No trauma.
Patient Data
The normal position of the ulnar nerve with an extended elbow. Ulnar nerve dislocation with 90' flexion of the elbow. Additional triceps muscle medial head dislocation with complete elbow flexion. Relocation of the muscle followed by the ulnar nerve from flexion to extension elbow movement.
Two cine-loops are aligned to the ulnar nerve short-axis at the cubital tunnel. The first loop during elbow extension to the flexion position shows nerve followed by muscle dislocation. The second loop shows the expected relocation.
Two palpable snaps were present without an audible snap.
Ulnar nerve mild edema just proximal the cubital tunnel. No neural/ perineural lesion.
Case Discussion
A girl presented with clinical features of ulnar neuropathy. The nerve conduction velocity (NCV) test suggested nerve abnormality at the elbow, hence referred to evaluate the nerve. The ultrasound shows an ulnar nerve dislocation followed by triceps muscle medial head dislocation with elbow flexion and mild edema of the ulnar nerve.