Long Thoracic Nerve Anatomy

The long thoracic nerve is the tidiest nerve in the upper-limb syllabus: one nerve, one muscle, one sign. It is purely motor (C5–C7), supplies only serratus anterior, and its failure produces the unmistakable medial scapular winging that examiners love as a spot diagnosis. Its exam value comes from three linked ideas — the anatomy that explains its vulnerability (a long, superficial course down the chest wall), the clinical sign and how to elicit and distinguish it (medial vs lateral winging, wall push-up), and the staged management (most recover, surgery is reserved). Build the topic around "why this nerve is so easily injured and how its single sign is told apart from trapezius winging."

• Protraction of the scapula (draws it forward around the chest wall - the "boxer's punch").
• Upward rotation of the scapula (with the trapezius force couple), which swings the glenoid upward to permit full arm elevation above 90 degrees.
• Scapulothoracic stabilisation - holds the medial border and inferior angle flat against the chest wall.

When serratus anterior fails, the scapula loses its anchor and upward-rotation contribution, producing both medial winging and loss of full overhead elevation.

Management is staged and depends on cause, duration and electrodiagnostic findings:

• Observation and physiotherapy first: most isolated long thoracic nerve palsies - especially neuralgic amyotrophy or traction injuries - recover spontaneously over months. Scapular stabilisation and range-of-motion physiotherapy are the mainstay, with recovery often awaited for up to two years.
• Nerve surgery (neurolysis / nerve transfer): for persistent palsy with no reinnervation, neurolysis of the long thoracic nerve can restore serratus function, with good or excellent results in the majority and best outcomes when performed within about 12 months. Nerve transfers (e.g. a branch of the thoracodorsal nerve to the long thoracic nerve) are an option.
• Tendon/muscle transfer (salvage): for established, irreversible palsy, pectoralis major (sternal head) transfer to the inferior scapula (dynamic stabilisation) is the classic reconstruction; scapulothoracic fusion is a salvage for refractory cases or generalised winging.

Global Practice Picture

The diagnosis and staged management of long thoracic nerve palsy are consistent internationally and rest on clinical examination plus electrodiagnostics rather than registries. The universal principles are: recognise the medial-winging pattern, exclude trapezius (lateral) winging and traumatic muscular detachment, allow spontaneous recovery for isolated/neuralgic cases, and reserve surgery for persistent palsy.

Side-by-Side Synthesis

Practice Variation

Electrodiagnostic access varies, but the clinical distinction between medial and lateral winging can be made anywhere with a careful examination. Non-operative care is the universal first step; the choice and availability of nerve versus tendon-transfer surgery for persistent cases varies with local expertise.