Anatomy Case Correlate “Shoulder Pain”

History 22 year old male, professional hockey player 6 week history of right shoulder pain No recent trauma Training heavily in the off-season Upper arm pain, increased with overhead activity, lifting

Physical Exam Normal motion Pain with lifting beyond 90 degrees Abduction 4+/5 and painful External rotation 4/5 Infraspinatus atrophy

Differential Rotator cuff Cervical spine Instability Nerve entrapment Labral tear Arthritis

Differential Inflammatory Tumor Infection Fracture Adhesive Capsulitis Intrathoracic Biceps

Rotator Cuff Impingement “Dynamic” pinching of the supraspinatus tendon between the humeral head and undersurface of acromion Force couple between deltoid and rotator cuff musculature

Rotator Cuff Disease Inflammatory Degeneration Partial Tearing Full Thickness Tearing Tears predictably begin in supraspinatus Part of normal aging process

Instability Static restraints Dynamic restraints (musculature) Osseous architecture Capsuloligamentous restraints Dynamic restraints (musculature)

Shoulder Instability Dislocation Subluxation More difficult diagnosis Suspect in younger patient with chronic post-traumatic shoulder pain, with or without history of instabilty

AC JOINT Traumatic event (separation) Arthritis (post-traumatic versus degenerative) Well localized pain, superior shoulder

Labral Tear Variable anatomy SLAP lesion (superior, labrum, anterior and posterior) Most common in repetitive overhead athletes

Approaching the Problem Subjective complaints  cuff tendinitis Abduction pain  cuff tendinitis No history of instability Pain not localized to AC joint No repetitive overhead sports

Approaching the Problem But, infraspinatus atrophy and external rotation weakness Massive rotator cuff tear Suprascapular neuropathy

Suprascapular Nerve Origin: C5 root or upper trunk of brachial plexus Suprascapular notch, beneath transverse scapular ligament Innervates supraspinatus Winds around spine of scapula Innervates infraspinatus

Further Work-up X-rays normal Electrodiagnostic studies  injury to suprascapular nerve at spinoglenoid notch  isolated denervation of infraspinatus Ganglion cyst?

Diagnosis Suprascapular neuropathy right shoulder secondary to ganglion cyst with possible superior labral tear at spinoglenoid notch

Treatment Right shoulder arthroscopy Labral debridement, arthroscopic decompression of the cyst Post op rehab, return to play at 6 weeks with full strength

Suprascapular Neuropathy It all starts with the anatomy Careful history + careful exam usually results in diagnosis Imaging studies, when necessary, support what you suspect from above