What should I do if I am unable to abduct my right shoulder after a fall?

Immediate Management of Inability to Abduct Right Shoulder After a Fall

You must obtain immediate three-view radiographs (anteroposterior in internal and external rotation, plus axillary or scapular Y view) before attempting any manipulation, as this presentation suggests possible fracture-dislocation or rotator cuff injury with potential neurovascular compromise. 1

Critical First Steps

Immediate Imaging Protocol

• Obtain standard three-view radiographs immediately to rule out fracture or dislocation, including AP views in both internal and external rotation, and critically, an axillary or scapular Y view 2, 1
• The axillary or scapular Y view is non-negotiable—dislocations are misclassified on AP views alone in over 60% of cases 1
• Perform upright imaging when possible, as supine imaging can underrepresent shoulder malalignment 1

Neurovascular Assessment

• Document radial pulse presence, capillary refill, and complete sensory/motor examination immediately before any intervention 1
• Test specifically for axillary nerve function (sensation over lateral deltoid/"regimental patch" area) and ability to contract deltoid muscle, as axillary nerve injury occurs in 5-35% of shoulder dislocations 3
• Assess for radial nerve function (wrist extension, thumb extension, sensation over dorsal first web space) and ulnar nerve function (finger abduction, sensation over ulnar hand distribution) 3

Interpretation of Initial Radiographs

If Radiographs Show Fracture or Dislocation

• Refer urgently to orthopedics without attempting reduction if any fracture-dislocation, displaced/unstable fractures, or any dislocation is present 1
• Attempting reduction without radiographic confirmation can worsen fracture-dislocations 1
• Obtain CT without contrast to characterize fracture patterns and confirm reduction success 1
• Order CT angiography if vascular compromise is suspected (absent/diminished radial pulse, expanding hematoma) 1

If Radiographs Are Normal But Abduction Remains Impossible

• Proceed to MRI without contrast or MR arthrography to evaluate for rotator cuff tears (particularly supraspinatus), labral injuries, or occult fractures 2, 1
• MRI is rated 9/9 ("usually appropriate") for suspected rotator cuff pathology when radiographs are noncontributory 2
• Ultrasound by experienced operators is equivalent to MRI for rotator cuff evaluation and can be performed immediately if expertise is available 2

Urgent Orthopedic Referral Indications

Refer immediately if any of the following are present:

• Any fracture-dislocation, displaced or unstable fractures, or any dislocation on radiographs 1
• Progressive neurological deficits during observation 1
• Absent or diminished radial pulse 1
• Complete inability to initiate shoulder abduction (suggests complete rotator cuff tear or axillary nerve injury requiring surgical evaluation) 2, 4

Management Pending Orthopedic Evaluation

Immobilization and Pain Control

• Place arm in sling for comfort and protection 4
• Avoid any forced movement or manipulation until imaging is complete and fracture/dislocation excluded 1
• Provide adequate analgesia to prevent muscle spasm and allow proper examination 4

Critical Pitfalls to Avoid

• Never attempt reduction without radiographic confirmation—fracture-dislocations can be catastrophically worsened 1
• Failure to obtain axillary or scapular Y views leads to missed dislocations, especially posterior dislocations which appear deceptively normal on AP views 1
• Delaying reduction (if dislocation confirmed) increases neurovascular complications 1
• Missing concomitant nerve injuries by inadequate initial documentation leads to medicolegal complications and delayed treatment 3

Special Considerations

Age-Related Factors

• In patients over 40 years, inability to abduct after trauma more commonly indicates rotator cuff tear than dislocation 4
• In younger patients (<25 years), dislocation with labral injury is more likely, and surgical stabilization should be strongly considered to prevent recurrent instability 5

Rotator Cuff Injury Patterns

• Pain during attempted abduction with weakness suggests rotator cuff tendinopathy or tear 2
• Complete inability to initiate abduction (arm drop sign) indicates complete supraspinatus tear or axillary nerve palsy requiring differentiation 2, 4
• Focal weakness with decreased range of motion during abduction with external or internal rotation confirms rotator cuff dysfunction 2