What are the possible causes of combined shoulder pain and hand numbness, and what is the recommended evaluation and initial management?

Shoulder Pain with Hand Numbness: Differential Diagnosis and Management

The combination of shoulder pain and hand numbness most commonly indicates cervical radiculopathy or nerve compression syndrome, requiring immediate evaluation of cervical spine pathology, thoracic outlet syndrome, and peripheral nerve entrapment before considering isolated shoulder pathology.

Critical Differential Diagnoses to Consider

Cervical Radiculopathy (Most Common)

• Cervical nerve root compression produces both neck/shoulder pain AND radiating arm numbness or sensory deficits, making this the primary diagnosis to rule out when these symptoms coexist 1
• Cervical spondylosis causes pain in the neck and shoulder area with radiating symptoms that can mimic rotator cuff pathology 2
• This condition is marked by nerve compression from herniated disk material or arthritic bone spurs, producing neck pain, radiating arm pain, numbness, sensory deficits, or motor dysfunction 1

Thoracic Outlet Syndrome

• Among patients with neck-shoulder-upper extremity pain, thoracic outlet syndrome accounts for 14.5% of single diagnoses, making it a critical consideration 3
• This nerve compression syndrome of the shoulder contributes to pain, paresthesia, and weakness of the upper extremity 4

Peripheral Nerve Entrapment

• Carpal tunnel syndrome accounts for 4.5% of single diagnoses in patients presenting with neck-shoulder-upper extremity pain 3
• Suprascapular neuropathy and quadrilateral space syndrome can produce overlapping shoulder pain and upper extremity symptoms 4

Complex Regional Pain Syndrome (Shoulder-Hand Syndrome)

• CRPS presents with shoulder pain PLUS hand involvement characterized by pain and tenderness of metacarpophalangeal and proximal interphalangeal joints, edema over the dorsum of fingers, trophic skin changes, hyperaesthesia, and limited range of motion 5
• This diagnosis is particularly relevant in post-stroke patients, where combined motor, sensory, and visuoperceptual deficits carry a 67% incidence rate 5

Essential Clinical Evaluation

Key History Elements

• Mechanism of onset: Trauma suggests fracture or soft tissue injury 6; gradual onset suggests degenerative or compressive etiology 1
• Pattern of numbness: Dermatomal distribution indicates cervical radiculopathy 1; diffuse hand numbness suggests thoracic outlet syndrome or carpal tunnel syndrome 3
• Presence of weakness or muscle atrophy: 30.4% of patients with upper extremity pain have muscle weakness, and 29.4% have muscle atrophy 3
• Stroke history: Post-stroke patients have up to 72% incidence of shoulder pain in the first year 7

Critical Physical Examination Findings

• Evaluate tone, strength, soft tissue changes, joint alignment of the shoulder girdle, and pain levels to identify specific impairments 6
• Test for painful arc between 60-120° of abduction/flexion, which is pathognomonic for subacromial pathology 8
• Assess rotator cuff strength: Normal strength rules out full-thickness tear 8
• Examine for hand edema, trophic skin changes, and hyperaesthesia to identify CRPS 5
• Perform cervical spine range of motion and Spurling's test to evaluate for cervical radiculopathy 1

Initial Imaging Strategy

• Obtain standard shoulder radiographs (AP views in internal/external rotation plus axillary or scapula-Y view) as the preferred initial diagnostic modality to evaluate for fracture, dislocation, or malalignment 6
• MRI or CT myelography of the cervical spine confirms neurologic compression when cervical radiculopathy is suspected 1
• Triple phase bone scan demonstrates increased periarticular uptake in distal upper extremity joints to assist in CRPS diagnosis 6

Management Algorithm

When Cervical Radiculopathy is Suspected

• Most patients improve over time with focused nonoperative treatment 1
• Use cervical collars for short-period immobilization 1
• Consider traction to temporarily decompress nerve impingement 1
• Prescribe medications to alleviate pain and neuropathic symptoms 1
• Implement physical therapy and manipulation to improve neck discomfort 1

When Isolated Shoulder Pathology with Referred Symptoms

• Start with gentle passive and active-assisted range of motion exercises, placing the arm in safe positions within the patient's visual field 8
• Focus specifically on external rotation and abduction movements, as external rotation is the most significantly affected motion and relates most strongly to shoulder pain onset 7, 8
• Prescribe ibuprofen before bedtime for superior pain relief compared to acetaminophen 8
• Subacromial corticosteroid injection is indicated when pain is clearly related to rotator cuff or bursa inflammation 6, 8

When CRPS (Shoulder-Hand Syndrome) is Diagnosed

• Initiate an early course of oral corticosteroids starting at 30-50 mg daily for 3-5 days, then taper over 1-2 weeks to reduce swelling and pain 6
• Implement active, active-assisted, or passive range of motion exercises to prevent progression 6, 5
• Use analgesics such as acetaminophen or ibuprofen if no contraindications exist 6
• For shoulder pain related to spasticity, inject botulinum toxin into the subscapularis and pectoralis muscles 6

Critical Pitfalls to Avoid

• Never assume isolated shoulder pathology without evaluating the cervical spine, as cervical spondylosis frequently mimics rotator cuff pathology 2
• Avoid overhead pulley exercises in at-risk patients, as they encourage uncontrolled abduction and dramatically increase hemiplegic shoulder pain incidence 5, 7
• Do not delay imaging when red flags are present: Progressive weakness, muscle atrophy, or failure to improve after 3-4 weeks of conservative management warrants MRI and specialist referral 8, 3
• Consider autoimmune rheumatic diseases in patients presenting with upper extremity swelling: 36.4% of patients with upper extremity swelling in one series had autoimmune rheumatic diseases 3

Age-Specific Considerations

• Development of neck-shoulder-upper extremity pain is primarily observed in individuals aged 51-60 years (35.4% of cases) 3
• Younger patients with trauma require evaluation for fractures, dislocations, and soft tissue injuries 6
• Post-stroke patients require vigilant monitoring for CRPS development, particularly those with combined motor, sensory, and visuoperceptual deficits 5