Which nerve in the neck or shoulder is most commonly compressed and causes pain, weakness, or tingling?

The C6 and C7 nerve roots are the most commonly compressed nerves in the neck, while the suprascapular nerve is the most commonly compressed nerve in the shoulder region.

In the cervical spine, C6 and C7 radiculopathy account for the majority of cervical nerve compression cases, with an annual incidence of cervical radiculopathy estimated at 83 per 100,000 persons 1. These nerve roots are typically compressed by herniated discs or degenerative changes (osteophytes, facet joint arthropathy, uncovertebral joint hypertrophy).

Cervical Nerve Compression (Neck)

Clinical Presentation:

• Neck pain radiating to the upper extremity
• Sensory deficits in specific dermatomal distributions
• Motor weakness in corresponding myotomes
• Pain often worse with neck extension or rotation toward the affected side

Key Diagnostic Approach:

The diagnosis requires combining clinical findings with imaging, as physical examination alone has limited accuracy for diagnosing cervical radiculopathy 1. Importantly, 75-90% of cervical radiculopathy cases resolve with conservative nonoperative therapy 1, so aggressive imaging is not always necessary initially.

Imaging Algorithm:

• Radiographs first for initial screening of spondylosis, degenerative disc disease, and malalignment 1
• MRI without contrast is the most sensitive modality for soft tissue evaluation and nerve root compression, but should only be ordered when "red flag" symptoms or radiculopathy symptoms are present 1
• CT is less sensitive than MRI for nerve root compression, particularly with disc herniations 1

Critical Pitfall: MRI frequently shows abnormalities in asymptomatic patients (53.9% demonstrate disc degenerative changes) 1, and abnormal MRI levels don't always correspond to clinical examination findings 1. Never diagnose cervical radiculopathy on MRI alone—always correlate with clinical findings 1.

Shoulder Nerve Compression

The suprascapular nerve is the most commonly entrapped nerve in the shoulder region 2, 3, 4. This nerve follows a tortuous course from the neck to the posterior shoulder and is vulnerable at two key locations:

Anatomical Compression Sites:

• Suprascapular notch (more proximal)
• Spinoglenoid notch (more distal)

Clinical Presentation:

• Non-specific shoulder pain (often the only initial symptom) 5
• Weakness and atrophy of supraspinatus and/or infraspinatus muscles (late finding)
• Pain worse with overhead activities
• May coexist with rotator cuff tears or labral pathology 2

Causes of Compression:

• Ganglion cysts (particularly spinoglenoid cysts) 3, 5
• Ligamentous constraints at the notches
• Traction injury from overhead sports
• Massive retracted rotator cuff tears in older patients 3

Diagnostic Approach:

• Detailed history focusing on overhead activities and duration of symptoms
• Symmetrical shoulder examination comparing both sides
• Evaluate for muscle atrophy in supraspinatus/infraspinatus distribution 2
• MRI is the primary imaging modality to visualize ganglion cysts and muscle denervation patterns 6, 5
• Electrodiagnostic studies to confirm nerve involvement
• Consider diagnostic local anesthetic injection to the entrapment site 2

Treatment Algorithm:

• Conservative management first for isolated entrapment without space-occupying lesions: activity modification and physical therapy for at least 6 months 2, 3
• Surgical decompression indicated for: failure of conservative treatment, presence of ganglion cysts or masses, or progressive muscle atrophy 2, 3
• Both open and arthroscopic approaches provide reliable pain relief; arthroscopic has advantage of addressing concurrent intra-articular pathology 3

Important Caveat: Suprascapular neuropathy is often a diagnosis of exclusion and frequently missed because the initial presentation is non-specific shoulder pain 2, 5. Maintain high clinical suspicion, especially in overhead athletes or patients with persistent shoulder pain despite treatment for presumed rotator cuff pathology.

Other shoulder nerve compressions include axillary nerve (quadrilateral space syndrome), long thoracic nerve palsy, and thoracic outlet syndrome, but these are less common than suprascapular neuropathy 4, 7.