What does tenderness of the coracoid process indicate?

Tenderness of the Coracoid Process: Clinical Significance and Diagnostic Implications

Tenderness of the coracoid process most commonly indicates subcoracoid impingement syndrome, musculoskeletal injury, or referred pain from surrounding shoulder structures. This finding requires careful evaluation as it may represent various pathologies affecting the shoulder complex.

Clinical Significance of Coracoid Process Tenderness

• Coracoid process tenderness on palpation is an important physical examination finding that can help differentiate between various shoulder pathologies 1
• The coracoid process serves as a critical anchor for many tendinous and ligamentous attachments including the pectoralis minor, coracobrachialis, short head of biceps brachii, and several important ligaments (coracoclavicular, coracohumeral, coracoacromial, and transverse scapular) 2
• Localized tenderness at the coracoid process is a key diagnostic sign of subcoracoid impingement syndrome 3

Common Conditions Associated with Coracoid Process Tenderness

Subcoracoid Impingement Syndrome

• Characterized by pain at the anterior aspect of the shoulder, localized tenderness of the coracoid process, and anterior shoulder pain on horizontal adduction testing 3
• Often presents as persistent pain after rotator cuff surgery or other shoulder procedures 3
• Histopathologic findings reveal hypertrophic changes of the fibrocartilage layer at the posterior aspect of the coracoid process in affected patients 3

Coracoid Process Fracture or Nonunion

• Fractures of the coracoid process may cause localized tenderness and can be classified using Ogawa's functional classification 4
• Nonunion of coracoid fractures (CN) may be asymptomatic in many cases but can produce localized tenderness when symptomatic 4
• Coracoid fractures are often missed on initial evaluation, with oversight by physicians being the most frequent cause of nonunion 4

Musculoskeletal Causes

• Tenderness may indicate costochondritis or Tietze syndrome when it involves the anterior chest wall structures near the coracoid 1
• May be part of a broader pattern of musculoskeletal chest pain, which typically reproduces symptoms on palpation 1

Diagnostic Approach

Physical Examination

• A focused cardiovascular and musculoskeletal examination should be performed to distinguish between serious causes of chest/shoulder pain and localized musculoskeletal issues 1
• Specific tests to evaluate for subcoracoid impingement include:
  • Horizontal adduction test (positive if it reproduces anterior shoulder pain) 3
  • Subcoracoid block (injection test) 3
  • Palpation for localized tenderness directly over the coracoid process 1

Imaging Studies

• Plain radiographs of the shoulder should be the initial imaging study to evaluate for fractures, dislocations, or other bony abnormalities 1
• When radiographs are normal or indeterminate but clinical suspicion remains high:
  • MRI without contrast is useful for evaluating soft tissue structures around the coracoid, including tendons and ligaments 1
  • CT without contrast may be helpful for better visualization of bony abnormalities when fracture is suspected 1

Management Considerations

• For subcoracoid impingement syndrome that doesn't respond to conservative treatment for 6 months, coracoplasty (partial resection of the posterolateral side of the coracoid process) may be indicated 3
• Fractures of the coracoid process may require surgical fixation if they are part of a complex injury pattern involving the superior shoulder suspensory complex 4
• When evaluating coracoid tenderness, it's important to assess for concurrent shoulder girdle injuries, as isolated coracoid pathology is relatively uncommon 4

Important Anatomical Considerations

• The coracoid process has five morphological types in the Chinese population (Vertical 8-shape, Long stick shape, Short stick shape, Water drop shape, and Wedge shape), which may influence clinical presentation and surgical approaches 5
• The coracoid serves as the "lighthouse of the shoulder" due to its proximity to major neurovascular structures and its role as a landmark for surgical approaches 2
• Understanding the anatomical relationships of the coracoid is crucial when evaluating tenderness in this region, as it may represent referred pain from adjacent structures 2