NERVE LIBRARY · Upper limb

Ulnar nerve

A reproducible focal across-elbow abnormality supports elbow localization. Dorsal ulnar sensory sparing can help assess a Guyon canal lesion.

Roots / nucleus: C8–T1; possible C7 contribution
Function: Mixed
3D protocols: 3 related protocols

01Course and sensory territory

The little finger, ulnar half of the ring finger and ulnar hand.

02Motor supply

ADM, FDI, interossei, FCU and ulnar FDP.

03Localization clues

A reproducible focal across-elbow abnormality supports elbow localization. Dorsal ulnar sensory sparing can help assess a Guyon canal lesion.

04Combine the studies

Record ADM/FDI, measure the across-elbow segment and assess ulnar and DUC SNAPs. Select forearm and non-ulnar C8–T1 muscles to test the hypothesis.

Explore the related 3D protocols

Ulnar sensoryG1 / G2 / Stimulation ↗Ulnar motorG1 / G2 / Stimulation ↗Dorsal ulnar cutaneous sensoryG1 / G2 / Stimulation ↗

These retain the existing source-supported landmarks and references. The 3D model is educational; clinical work requires palpation and measured distances.

Connect to a clinical question

Exclude technical artifacts first Conduction block and temporal dispersion Ulnar nerve: elbow, wrist or C8–T1?Brachial Plexopathy Repetitive stimulation and the NMJ Recognize anomalous innervation

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References and further reading

Ulnar Nerve Mononeuropathy at the Elbow ↗AAPM&R KnowledgeNow · Society educational review · Link accessed 2026-09-08
Ulnar Mononeuropathy at the Wrist ↗AAPM&R KnowledgeNow · Society educational review · Link accessed 2026-09-08

Educational synthesis; independent neuromuscular specialist review is pending. Publication dates and compilation dates are distinct. This is an original teaching synthesis; consult the source for complete methods and criteria.