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02 · EMG · Anatomy

Interactive Plexus

Roots to trunks to cords to nerves — click through the wiring, break it on purpose, and let the pattern of weakness teach the localization.

Click any structure to trace its pathway — everything upstream and downstream lights up.

C5C5C6C6C7C7C8C8T1T1Upper TrunkUpper TrunkMiddle TrunkMiddle TrunkInferior TrunkInferior TrunkAnt. Div (Upper)Ant. Div (Upper)Post. Div (Upper)Post. Div (Upper)Ant. Div (Middle)Ant. Div (Middle)Post. Div (Middle)Post. Div (Middle)Ant. Div (Inf)Ant. Div (Inf)Post. Div (Inf)Post. Div (Inf)Lateral CordLateral CordPosterior CordPosterior CordMedial CordMedial CordDorsal ScapularDorsal ScapularLong ThoracicLong ThoracicSuprascapularSuprascapularN. to SubclaviusN. to SubclaviusLat. PectoralLat. PectoralMusculocutaneousMusculocutaneousLat. Root MedianLat. Root MedianUpper SubscapularUpper SubscapularThoracodorsalThoracodorsalLower SubscapularLower SubscapularAxillaryAxillaryRadialRadialMed. PectoralMed. PectoralMBC (Med. Cut. Arm) — Medial Brachial Cutaneous (MBC). Sensory branch off the medial cord. Provides sensation to the medial arm. Key SNAP for lower trunk / medial cord lesions (spares post-ganglionic in radiculopathies).MBC (Med. Cut. Arm)MAC (Med. Antebrach. Cut.) — Medial Antebrachial Cutaneous (MAC). Sensory branch off the medial cord. Provides sensation to the medial forearm. Critical SNAP for diagnosing lower trunk / medial cord plexopathies (e.g., true neurogenic TOS).MAC (Med. Antebrach. Cut.)LAC (Lat. Antebrach. Cut.) — Lateral Antebrachial Cutaneous (LAC). Sensory terminal branch of the musculocutaneous nerve. Provides sensation to the lateral forearm. Critical SNAP for upper trunk / lateral cord lesions (e.g., Parsonage-Turner, upper trunk plexopathy).LAC (Lat. Antebrach. Cut.)UlnarUlnarMed. Root MedianMed. Root MedianMedian NerveMedian Nerve

Tap a stage chip or pinch to zoom · tap a structure for details

SelectedUpstream pathwayDownstream territory

Structure details

Click a structure in the diagram. Its upstream pathway (gold) and downstream territory (terracotta) light up, with details here.