Scapular Winging

Serratus Anterior and the Long Thoracic Nerve

• Origin/insertion: Arises from the upper 8 or 9 ribs, wraps around the chest wall, and inserts on the deep surface of the medial scapular border.
• Action: Protracts the scapula and, crucially, produces upward rotation so the glenoid faces up for overhead reach. It also holds the medial border flat against the thorax.
• Nerve: Long thoracic nerve (the nerve of Bell), roots C5, C6, C7. It runs superficially on the surface of serratus anterior, making it vulnerable to traction and direct trauma.
• Failure: Loss produces medial winging - the medial border lifts off and drifts towards the spine, and forward elevation is limited and weak.

Trapezius and the Spinal Accessory Nerve

• Three parts: Upper (elevates and rotates), middle (retracts), lower (depresses and rotates) - together they suspend and upwardly rotate the scapula.
• Nerve: Spinal accessory nerve (cranial nerve XI). It runs superficially across the posterior triangle of the neck, where it is easily injured during lymph node biopsy or neck dissection.
• Failure: Loss produces lateral winging - the shoulder droops, the scapula translates laterally and rotates downward, and abduction is weak. The neckline looks asymmetric.

Rhomboids and the Dorsal Scapular Nerve

• Action: Rhomboid major and minor retract and stabilise the medial border; levator scapulae elevates the superior angle.
• Nerve: Dorsal scapular nerve (C5).
• Failure: Rare, subtle medial winging with the scapula translated slightly laterally and the inferior angle rotated outward - the opposite rotation to serratus palsy. Often missed.

Medial vs Lateral (the working classification)

• Medial (dynamic) winging: Serratus anterior palsy. Inferior angle rotates towards the midline; winging worst on forward flexion / wall push-up.
• Lateral winging: Trapezius palsy. Scapula translates laterally, inferior angle rotates outward, shoulder droops; winging worst on abduction.
• This direction-based split is the most useful clinically because it points straight to the nerve.

Neurogenic vs Muscular vs Bony

• Neurogenic: Long thoracic (serratus), spinal accessory (trapezius), dorsal scapular (rhomboids). Most common.
• Muscular / soft tissue: Direct avulsion or tear of serratus, trapezius or rhomboids; facioscapulohumeral muscular dystrophy (FSHD).
• Bony / mechanical: Osteochondroma of the scapular undersurface, malunion, scapulothoracic bursitis ("snapping scapula") causing pseudo-winging.

Conservative Management (first line for neurogenic palsy)

• Why: Most neurogenic winging recovers spontaneously - the traditional teaching is recovery within around 2 years for long thoracic nerve palsy.
• What: Physiotherapy (scapular stabiliser strengthening, range of motion to avoid stiffness), activity modification, and analgesia.
• Bracing: Scapulothoracic orthoses are described but are often poorly tolerated.
• Duration: Continue for roughly 12 to 24 months with serial clinical and EMG review for reinnervation before considering salvage.

According to PubMed, most patients with serratus palsy regain function with conservative treatment, although recovery may take up to 2 years, and bracing is often poorly tolerated (Wiater and Flatow, 1999).

Nerve-Directed Surgery (selected cases)

• Neurolysis / decompression: For persistent isolated long thoracic nerve palsy not recovering on conservative care, decompression and neurolysis of the nerve can improve winging.
• Nerve repair / graft: For sharp, recognised spinal accessory nerve transection - early repair within about 1 year offers the best chance of recovery.
• Timing matters: Outcomes are best when nerve surgery is done within roughly 12 months of onset.

According to PubMed, in isolated long thoracic nerve palsy with persistent winging that fails conservative care, neurolysis of the nerve can be considered, and outcomes are best when surgery is performed within around 12 months of paralysis (Ng et al., 2024; Roulet et al., 2022).

Salvage Tendon Transfers (fixed palsy)

• Serratus anterior palsy (medial): Pectoralis major (sternal head) transfer to the inferior angle of the scapula, often reinforced with fascia/tendon graft, is the procedure of choice.
• Trapezius palsy (lateral): Eden-Lange transfer - levator scapulae and both rhomboids are moved laterally to recreate the trapezius force vectors.
• FSHD / non-reconstructable muscle: Scapulothoracic arthrodesis (fusion) stabilises the scapula and improves elevation when the muscles cannot be restored.

Pectoralis Major Transfer (for serratus palsy)

• Goal: Replace the lost upward-rotation and stabilising pull of serratus anterior.
• Principle: The sternal head of pectoralis major is mobilised and transferred to the inferior angle of the scapula, usually lengthened with an autograft (fascia lata, hamstring) to reach.
• Steps:
  1. Two-incision approach (anterior axillary fold and over the inferior scapular angle).
  2. Harvest the sternal head of pectoralis major.
  3. Lengthen with fascial/tendon graft if needed.
  4. Pass deep to the chest wall soft tissue to the inferior angle.
  5. Fix to the scapula and tension with the arm at the side.

According to PubMed, transfer of the sternal head of pectoralis major to the inferior angle of the scapula reinforced with fascia or tendon autograft consistently improves function, eliminates winging and reduces pain (Wiater and Flatow, 1999; Galano et al., 2008; DOI).

Eden-Lange Transfer (for trapezius palsy)

• Goal: Recreate the three force vectors of the paralysed trapezius.
• Classic transfer:
  • Levator scapulae transferred laterally onto the scapular spine (replaces upper trapezius).
  • Rhomboid minor and major transferred laterally onto the scapular body (replace middle and lower trapezius).
• Modified (Elhassan) version: Triple-tendon transfer with the levator, rhomboid minor and rhomboid major moved further laterally to better restore the native vectors, used as a salvage for chronic trapezius palsy.

According to PubMed, the Eden-Lange procedure transfers the levator scapulae, rhomboid minor and rhomboid major laterally and relieves pain, corrects deformity and improves function in irreparable spinal accessory nerve injury (Wiater and Bigliani, 1999; Gong et al., 2023; DOI).

Scapulothoracic Arthrodesis (for FSHD)

• Goal: When the stabilising muscles cannot be restored (dystrophy), fuse the scapula to the rib cage so the deltoid can elevate the arm.
• Technique: Plate-and-wire construct with iliac crest autograft interposed between scapula and ribs.
• Trade-off: Improves elevation and reduces winging, but it is a fusion - and bilateral fusion raises a theoretical concern about restricting the chest wall and respiratory function.

According to PubMed, bilateral scapulothoracic arthrodesis in FSHD gave a 90 percent fusion rate, gained around 40 degrees of forward elevation, raised the Subjective Shoulder Value from 25 to 72 percent, and showed no significant fall in vital capacity (Boileau et al., 2020; DOI).

Missed or Wrong Diagnosis

• Calling lateral (trapezius) winging "serratus palsy" sends the surgeon to the wrong operation.
• Missing FSHD or neuralgic amyotrophy leads to inappropriate early surgery.

Always confirm the direction of winging and back it with EMG.

Tendon-Transfer Problems

• Graft stretch or rupture, recurrence of winging, and under-tensioning.
• Wound problems - superficial infection is the commonest reported complication in transfer series.

Adequate graft length and secure scapular fixation reduce recurrence.

Scapulothoracic Fusion Risks

• Pneumothorax and pleural effusion (rib instrumentation).
• Non-union and hardware problems.
• Theoretical restriction of chest-wall excursion after bilateral fusion.

Careful subperiosteal rib technique limits pleural injury.