What is the best management plan for a patient with left shoulder pain radiating to the head, sleep disturbance, and numbness in the arm?

Management of Left Shoulder Pain with Radicular Symptoms and Sleep Disturbance

This patient requires immediate plain radiographs (AP views in internal and external rotation plus axillary or scapula-Y view) to rule out fracture or dislocation, followed by MRI or ultrasound to evaluate rotator cuff pathology, combined with conservative management including physical therapy, analgesics, and sleep hygiene interventions. 1

Immediate Diagnostic Workup

Initial Imaging

• Obtain standard shoulder radiographs first (AP views in internal and external rotation plus axillary or scapula-Y view) to exclude fracture, dislocation, or significant bony pathology 1
• Radiographs are the preferred initial diagnostic modality and must precede advanced imaging 1

Advanced Imaging Based on Clinical Presentation

Given the clinical findings of limited abduction <90°, pain on internal rotation against resistance, and paraspinal tenderness with radicular symptoms:

• MRI shoulder without contrast is indicated to evaluate rotator cuff pathology (likely rotator cuff tear or tendinopathy given the pain pattern, limited range of motion, and nighttime symptoms) 1
• Ultrasound is an equivalent alternative if local expertise is available and can be performed with therapeutic injection if warranted 1
• The radiation to the neck and head suggests possible cervical spine involvement requiring differentiation from primary shoulder pathology 2

Conservative Management Strategy

Pain Management

• Start with acetaminophen or ibuprofen for pain relief if no contraindications exist 1
• Dosage should be kept to minimum effective dose 1
• The patient's pain severity of 8/10 and inability to sleep warrants aggressive initial pain control 3

Physical Therapy Interventions

• Initiate gentle stretching and mobilization techniques focusing on increasing external rotation and abduction gradually 1
• Active range of motion should be increased in conjunction with restoring alignment and strengthening weak shoulder girdle muscles 1
• Refer to physiotherapist for individually tailored graded physical exercise given the significant functional limitation (cannot lift heavy objects, limited abduction <90°) 1

Sleep Disturbance Management

This is critical as 91-93% of patients with rotator cuff injuries experience nighttime pain, and sleep disturbances significantly impact quality of life 3, 4:

• Provide education about good sleep hygiene practices including optimal sleeping positions (avoiding the affected side) 1
• Address the specific causes: pain is the primary driver but functional limitations also contribute 3, 4
• Consider short-term hypnotic medication (lowest effective dose for shortest period) only if daytime impairment is severe and conservative measures fail 1
• Avoid long-acting benzodiazepines; if pharmacotherapy needed, consider short-acting non-benzodiazepine options like zaleplon or zolpidem for brief periods 1

Addressing Neurological Symptoms

The numbness in the left arm at night and occasional paresthesias in the 3rd finger require specific attention:

• 33% of patients with rotator cuff pathology report hand paresthesia that improves with treatment of the shoulder condition 5
• These symptoms typically improve by 50-60% within one week of appropriate treatment 5
• However, cervical spine pathology must be ruled out as cervical spondylosis can mimic rotator cuff pathology with radiating arm pain and paresthesias 2
• If symptoms persist despite shoulder treatment, consider cervical spine imaging 2

Injection Therapy Considerations

If conservative management fails after appropriate trial:

• Subacromial corticosteroid injection can be used if pain is related to subacromial pathology (rotator cuff or bursa) 1
• Botulinum toxin injection into subscapularis and pectoralis muscles may be considered if spasticity contributes to pain 1
• Injections should be fluoroscopy or ultrasound-guided for accuracy 1

Psychosocial Factors

The patient's recent redundancy (job loss) is a significant psychosocial stressor:

• Screen for psychological factors including depression, anxiety, and catastrophizing cognitions that may interfere with pain management 1
• If psychosocial factors impede recovery, consider referral to psychologist or cognitive-behavioral therapy 1
• Social support and self-management programs may be beneficial 1

Metabolic Considerations

The patient is pre-diabetic on metformin:

• Pre-diabetes and diabetes are associated with increased risk of rotator cuff pathology and adhesive capsulitis
• Optimize glycemic control as part of comprehensive management
• Monitor for development of adhesive capsulitis, which has significantly worse sleep quality (Pittsburgh Sleep Quality Index score of 12.07) compared to other shoulder conditions 4

Red Flags Requiring Urgent Evaluation

Critical pitfall to avoid: The combination of shoulder pain radiating to the head with arm numbness could represent:

• Pancoast tumor (apical lung tumor) causing shoulder pain with neurological symptoms 6
• While less likely given the examination findings, obtain chest radiograph if constitutional symptoms present or if symptoms don't improve with conservative management 6

Timeline for Reassessment

• Reassess at 1-2 weeks for pain improvement and functional gains
• If no improvement by 6 weeks of conservative management, consider surgical consultation 1
• Massive rotator cuff tears may require expedited surgical timeline for optimal outcomes 1
• Sleep quality and paresthesias should improve within 1 week if shoulder pathology is the primary cause 5