Approach

• Expose fully to waist

1. Look

   

   • Asymmetry of shoulders
   • Obvious winging
   • Bilateral involvement?
2. Feel
3. Move
   • Ask patient to abduct arm above horizontal (may be difficulty)
   • Push hands against wall to accentuate

Completion

1. Examine upper limb

Causes:

Weakness of serratus anterior due to:

1. Nerve injury - long thoracic nerve of bell
   • Axillary surgery (esp breast)
   • upper brachial plexus injury
   • Viral infections of nerve roots
2. Muscle injury
   • Muscular dystrophy