Suprascapular Neuropathy

Suprascapular neuropathy (SN) arises from compression or injury of the suprascapular nerve. It manifests as deep posterior–lateral shoulder pain, weakened abduction and external rotation, and, in advanced cases, visible wasting of the supraspinatus and/or infraspinatus muscles. Though uncommon—accounting for 1–4 % of shoulder pain cases—SN is increasingly recognised in overhead athletes. Early, accurate diagnosis and tailored treatment (from conservative rehabilitation to surgical decompression) yield the best outcomes and minimise permanent muscle loss.

Anatomy & Pathophysiology

1. Nerve Origin & Function
   • Arises from C5 ± C6 (± C4) roots of the upper brachial plexus.
   • Motor: supraspinatus (initiates abduction) and infraspinatus (external rotation).
   • Sensory: acromioclavicular and glenohumeral joints, coracoacromial ligament, subacromial bursa, occasionally lateral‐arm skin.
2. Entrapment Sites
   • Suprascapular notch: Under the superior transverse scapular ligament → affects both muscles.
   • Spinoglenoid notch: Beneath the spinoglenoid ligament → affects infraspinatus only.
3. Predisposing Variations
   • Ossified or V-shaped suprascapular notch morphologies increase entrapment risk.
   • Tight spinoglenoid ligament, especially with overhead activity.
4. Mechanisms of Injury
   • Dynamic (primary): Repetitive overhead motion (“sling effect”) stretches/kinks the nerve.
   • Static (secondary): Ganglion cysts, fractures, massive rotator cuff tears, postoperative scarring, systemic neuropathies.

Clinical Presentation

• Pain: Deep, dull ache in the posterior shoulder; worse with overhead use.
• Weakness: Difficulty with abduction (supraspinatus) and/or external rotation (infraspinatus).
• Atrophy: Visible wasting in the supraspinatus and/or infraspinatus fossae confirms chronic compression.
• Examination:
  • Tenderness over the notches.
  • Strength testing (Jobe’s test for supraspinatus; resisted external rotation for infraspinatus).
  • Special tests:
    • Suprascapular stretch: Neck turned away + shoulder traction → posterior‐shoulder pain.
    • Cross‐arm adduction: Arm across chest + internal rotation → posterior‐shoulder pain.

Diagnosis

1. Imaging
   • MRI: Gold standard—shows cysts, muscle oedema/atrophy/fatty change, nerve course.

1. • CT: Detailed bone anatomy (notch morphology, ossified ligaments).
   • Ultrasound: First‐line for dynamic/cystic lesions and guided injections.
   • X-ray: Stryker notch view for bony variants; otherwise to exclude other pathology.
2. Electrodiagnostics
   • EMG/NCS: Confirms denervation (fibrillations, sharp waves) and slowed conduction; 70–90 % sensitivity.
3. Diagnostic Block
   • Local anaesthetic injection into the notch; pain relief supports SN diagnosis.

Management

1. Conservative

• Activity modification: Avoid aggravating overhead motions.
• Physiotherapy:
  • Strengthen rotator cuff, periscapular, deltoid muscles (concentric & eccentric).
  • Improve scapular control and shoulder flexibility.
• NSAIDs and corticosteroid injections for pain/inflammation.
• Thermal therapy: Heat or ice as needed.
• Minimally invasive (if > 6 months without improvement): neurostimulation, cryoneurolysis, pulsed radiofrequency.

1. Surgical

• Indications: Persistent symptoms despite ≥ 6 months of rehab, muscle atrophy, or identifiable lesion on imaging.
• Arthroscopic decompression (gold standard):
  • Release of the transverse scapular ligament at either notch; optional notchplasty.
  • Concomitant cyst decompression or labral repair when indicated.
• Open decompression: Posterior or anterior approach if required.

1. Rehabilitation Post-Op

• Early gentle range‐of‐motion exercises under physiotherapy guidance.
• Sling for comfort until strength restores (4–8 weeks).
• Progressive strengthening thereafter.

Prognosis & Prevention

• Early Intervention (< 6 months) → > 80 % chance of significant pain relief and return to previous activities.
• Muscle recovery depends on chronicity; prolonged atrophy may not fully reverse.
• Preventative strategies:
  • Educate on proper overhead technique.
  • Regular rotator cuff and scapular stabiliser conditioning.
  • Ergonomic adjustments for repetitive tasks.

If you have pain, book an appointment to be reviewed by Prof Imam or another member of our specialist team at The Arm Clinic. Early specialist care helps prevent long-term issues. Visit www.TheArmDoc.co.uk or book your consultation today. Phone: 020 3384 5588 | Email: Info@TheArmDoc.co.uk