Case of the Month – Shoulder Dislocation with Radial Nerve Palsy in a Young Rugby Player

Why this case?

Shoulder dislocations are common in contact sports such as rugby. Nerve injuries are a recognised complication, with reported rates ranging from around 0.4% up to over 20%, depending on how actively you look for them. 

The axillary nerve is most often affected, while isolated radial nerve palsy is rare, but important not to miss. (MDPI)

This case highlights the importance of a structured neurovascular assessment after shoulder dislocation, early recognition of radial nerve injury, and coordinated rehab to protect both shoulder function and hand/wrist mechanics.

Key Takeaways & Learning Points

1. Always perform and document a focused neurovascular exam after shoulder dislocation and reduction. 

Including axillary, radial, median and ulnar nerve function, plus pulses. Nerve injuries are more common than many clinicians realise, particularly in high-energy trauma. (MDPI)

2. Radial nerve palsy is rare, but real.

Wrist drop and dorsal hand sensory loss should raise suspicion and prompt urgent specialist review, even when X-rays look reassuring. (ResearchGate)

3. Avoid prolonged sling immobilisation, it increases stiffness and delays recovery.

Patients should be educated early on appropriate sling weaning. Excessive immobilisation risks secondary adhesive capsulitis, particularly in young, active individuals.

4. Parallel rehabilitation programmes are required, one for the shoulder, one for the hand/nerve deficit.

Rehab must address scapular control, shoulder range of motion and rotator cuff function while simultaneously protecting hand position, using splinting and directed hand therapy to maintain mobility and function.

5. Early imaging and nerve conduction studies help clarify injury severity and guide management.

MRI helps exclude structural injury affecting stability or return-to-play decisions, while EMG/NCS differentiate neuropraxia from higher-grade nerve injury and inform prognosis and referral timelines. (MDPI)

6. Return-to-sport planning must consider both shoulder stability and nerve recovery.

Full wrist and finger extension, functional hand use, adequate grip strength and stable, pain-free shoulder mechanics are essential before a contact athlete returns to full rugby participation.

Clinical Presentation

History

A 20-year-old right-hand-dominant male club-level rugby player presented two weeks after a traumatic right shoulder injury:

• Mechanism: Slipped on a wet pitch during a match and landed with the right arm outstretched in abduction and external rotation.
  
• Immediate symptoms: Severe shoulder pain with obvious deformity and loss of shoulder contour, consistent with anterior dislocation.
  
• Initial care:
  
  • Attended A&E the same day.
    
  • Required procedural sedation; reduction took two attempts.
    
  • Post-reduction X-rays confirmed congruent glenohumeral joint with no associated fracture.
    
• Post-injury symptoms:
  
  • Persistent numbness from the posterior upper arm (triceps region), down the posterior forearm to the dorsum of the hand.
    
  • Profound weakness of wrist and finger extension – classic “wrist drop.” Present before reduction.
    
  • Ongoing shoulder pain, especially with overhead activities and when dressing.
    
  • Over the last 3 days, new shooting pains down the posterior forearm when the arm hangs by his side.
    

He had been placed in a sling in A&E and had worn this almost continuously for two weeks.

Activities of daily living

• Marked difficulty dressing, especially pulling T-shirts or shirts on and off overhead.
  
• Struggling with basic tasks such as lifting a kettle or typing with both hands due to wrist drop.
  
• Sleep disturbed by shoulder discomfort when rolling onto the right side.
  
• Able to continue office-based work in event management, but worried about long-term function and a return to rugby and social activities (e.g. going out, carrying bags, holding drinks).
  

Past medical & drug history

• No significant past medical history.
  
• First-time shoulder dislocation.
  
• No regular medication; no history of neurological disease.
  

Exercise History

• Plays competitive amateur rugby as a back, training 2–3 times per week with weekly matches.
  
• Additional gym-based strength training 1–2 times per week, focused on compound lifts and upper-body strength.
  
• No previous shoulder instability, contact injuries, or brachial plexus/“stinger” episodes.

Clinical Examination

General

• Slim, athletic young male in no acute distress.
  
• Right arm initially supported in a sling.

Shoulder Examination

• Posture: Shoulder held in a neutral, slightly protective position. No gross deformity or bruising, no obvious scapular winging.
  
• Range of Motion (active/passive):
  
  • Forward flexion: Limited by pain but functionally reasonable.
    
  • Abduction: ~100° on the affected side.
    
  • External rotation in neutral: 30° on the right vs 40° on the left.
    
  • Internal rotation: Mild restriction due to discomfort.
    
• Shoulder strength:
  
  • External and internal rotation strength preserved (rotator cuff power good but painful).
    
  • No obvious apprehension signs, though patient was guarded with abduction–external rotation.
    

These findings pointed towards capsular restriction and early stiffness rather than gross instability at this stage.

Neurological Examination (Right Upper Limb)

Motor:

• Wrist & finger flexion: 5/5.
  
• Wrist & finger extension: 1/5 (only trace movement), producing a clear wrist drop.
  
• Intrinsic hand muscles: Preserved, though function limited by inability to extend fingers.
  

Sensation:

• Reduced/light-touch sensation:

• Posterior upper arm and forearm.
• Dorsum of the hand, particularly over the thumb, index and middle fingers – classic radial nerve distribution.
• Axillary nerve territory (regimental badge area) sensation: Normal.
• Median and ulnar nerve dermatomes: Intact.

Reflexes:

• Triceps reflex difficult to assess reliably due to pain and weakness but not clearly absent.
  
• Biceps and brachioradialis reflexes: Normal and symmetrical.
  

Vascular & Cervical Assessment

• Radial, ulnar and brachial pulses palpable and symmetrical.
  
• No colour change, swelling or evidence of compartment syndrome.
  
• Cervical spine range of motion full and pain-free, with no reproduction of arm symptoms.
  

Initial Diagnostics

• Plain radiographs (ED): Confirmed successful relocation of the glenohumeral joint with no humeral head or shaft fracture and no obvious bony Bankart lesion.
  
• No initial cross-sectional imaging or nerve conduction studies were performed in A&E.
  

Given his ongoing neurological deficit at 2 weeks, we arranged:

1. MRI of the shoulder – to assess labral and capsular structures, rotator cuff, and any associated bone bruising or occult fracture.
   
2. EMG and nerve conduction studies – to characterise the radial nerve lesion (neuropraxia vs axonotmesis vs more proximal plexus involvement) and to provide a baseline for prognosis.

Working Diagnosis & Clinical Reasoning

Working diagnoses:

1. Traumatic anterior shoulder dislocation in a young rugby player, now with early capsular restriction and pain-limited range of motion.
   
2. Radial nerve palsy with wrist drop and sensory deficit in the radial nerve distribution, most likely a traction neuropathy related to the dislocation and/or reduction.
   

Why radial nerve palsy?

• Clear radial nerve motor involvement (wrist and finger extension 1/5) with preserved elbow extension suggests a lesion distal to the triceps branch in some cases; however, clinical patterns can overlap depending on the precise site of injury along the posterior cord/spiral groove. (ResearchGate)
  
• Sensory loss over the posterior arm/forearm and dorsum of the hand is in keeping with involvement of the posterior cutaneous nerve of the arm/forearm and superficial radial nerve.
  
• Axillary nerve function and sensation are preserved, making an isolated axillary mononeuropathy unlikely.
  
• Normal cervical spine exam and lack of dermatomal distribution or myotomal pattern reduce the likelihood of cervical radiculopathy.
  

Differentials considered

• Global brachial plexus injury – less likely given the isolated radial pattern and preserved other myotomes. (Hopkins Medicine)
  
• Humeral shaft fracture with radial nerve entrapment – excluded radiographically.
  
• Cervical nerve root lesion – clinical and planned imaging do not support this.
  

Given mechanism (contact sport, arm in abduction–external rotation, high traction forces) and the temporal association with dislocation and reduction, a traction neuropraxia of the radial nerve at or near the spiral groove/posterior cord remains the most plausible explanation.

Management Plan

1. Education & Sling Management

• Advised the patient to discontinue constant sling use, as prolonged immobilisation was contributing to capsular stiffness and could delay functional recovery.
  
• Recommended using the sling only in crowded/public settings for comfort and protection in the short term, with gradual weaning.
  

2. Shoulder Rehabilitation

Goals:

• Restore glenohumeral range of motion without provoking instability.
  
• Optimise scapular control and rotator cuff function.
  
• Prevent progression to adhesive capsulitis.
  

Key components:

• Early capsular mobilisation and passive/active-assisted ROM within pain limits (particularly external rotation and abduction). Gentle exercise such as pendulums to start 1-2 weeks after injury.
  
• Scapular stabilisation exercises focusing on serratus anterior and lower trapezius.
  
• Gradual progression to isometric then isotonic rotator cuff strengthening once pain and range allowed.
  

3. Hand Therapy & Splinting

Given his profound wrist drop, we initiated:

• A functional wrist extension splint to position the hand optimally for daily tasks and prevent flexion contractures.
  
• Passive and active-assisted ROM exercises for wrist and fingers to maintain joint mobility.
  
• Education on nerve protection – avoiding prolonged compression over the spiral groove, careful positioning during sleep and at the desk.
  

Hand therapy will be adjusted in response to EMG findings and any evidence of reinnervation.

4. Investigations and Timeline

• MRI shoulder – to exclude structural pathology that may alter management (e.g. significant Bankart lesion, humeral head bone loss, rotator cuff tear), especially in a young contact athlete who may later consider surgical stabilisation depending on recurrence risk and sport demands.
  
• EMG/NCS – initial study to confirm site and severity of radial nerve injury, with repeat testing at ~3 months if clinical recovery is unclear, in line with published series emphasising the need to characterise high-grade lesions early for timely referral. (MDPI)
  

5. Ongoing Follow-Up & Red Flags

• Review planned after MRI to:
  
  • Re-assess shoulder stability and range as well as repeat neurological exam
  • Review EMG findings and refine prognosis.
    
  • Adjust rehab and discuss return-to-play strategy.
    
• Clear safety-netting:
  
  • Worsening pain, new sensory changes, increasing weakness, or signs of vascular compromise would prompt urgent reassessment.
    
  • Failure to see any objective motor recovery in the radial nerve territory by ~3 months would trigger early discussion with peripheral nerve/shoulder surgeons.

Return to Rugby – Considerations

Return-to-play decisions will depend on two parallel recoveries:

1. Shoulder stability and function
   
   • Pain-free full ROM (or close to baseline) in flexion, abduction and external rotation.
     
   • No subjective instability or positive apprehension signs.
     
   • Satisfactory rotator cuff and scapular strength on objective testing.
     
2. Radial nerve recovery
   
   • Functional wrist and finger extension without need for splinting.
     
   • Grip strength sufficient for safe tackling, ball handling and contact scenarios.
     
   • Ideally, evidence of reinnervation on EMG as early weakness was marked. (MDPI)
     

Contact rugby would be deferred for at least several months, with progression through:

• Non-contact skills (passing, running drills).
  
• Controlled contact drills.
  
• Full training and finally competitive match play.

Conclusion

This case highlights the importance of a thorough, structured assessment and collaborative management approach when dealing with shoulder dislocation injuries in young athletes. 

While most clinicians are alert to axillary nerve involvement, this example reinforces the need to assess the entire neurovascular chain, as radial nerve palsy, though uncommon, can have significant functional implications if missed. 

Early recognition, appropriate splinting, timely imaging and electrodiagnostic studies, and a coordinated rehabilitation plan targeting both shoulder mechanics and distal nerve recovery are essential to optimise outcomes.

With careful monitoring, progressive rehabilitation, and clear return-to-play criteria, athletes with complex presentations such as this can recover function and stability safely. This case reinforces that early identification and proactive management not only protect long-term neuromuscular health but also support a safe and confident return to sport.