Differential Diagnosis for Hyperextension Shoulder Injury in a 13-Year-Old Football Player
In a 13-year-old football player with a hyperextension shoulder injury, you must prioritize physeal and apophyseal injuries unique to adolescents, followed by soft tissue injuries including glenohumeral instability, labral pathology, and ligamentous strains—recognizing that standard adult diagnoses like rotator cuff tears are uncommon in this age group.
Key Differential Diagnoses
Physeal/Growth Plate Injuries (Priority in Adolescents)
- Proximal humeral physeal stress injury ("Little League Shoulder"): Pain localized to the proximal humerus physis, worsened by rotational movements 1, 2
- Coracoid growth plate fracture (Salter-Harris type I): This is a critical diagnosis that can be missed on initial MRI and mistaken for labral pathology. Look for tenderness over the coracoid process 3
- These physeal injuries are distinct to skeletally immature athletes and should be your first consideration 4
Glenohumeral Instability
- Anterior traumatic instability: Most common in contact sports like football. Hyperextension with external rotation can cause anterior dislocation or subluxation 1, 4
- Multidirectional instability: Consider in adolescents with underlying hyperlaxity 4
- Recurrence rates are particularly high in this age group 1
Labral Pathology
- SLAP tears (Superior Labral Anterior-Posterior): Can occur but are frequently overdiagnosed on non-contrast MRI in adolescents 3
- Anterior or posterior labral tears: Associated with instability events 2
Ligamentous Injuries
- Glenohumeral ligament strains: Common with hyperextension mechanisms 3
- Coracoclavicular ligament strains: Often accompany coracoid injuries 3
- AC joint injuries: Account for 40-50% of shoulder injuries in contact sports, though typically from direct trauma rather than hyperextension 5
Fractures
- Proximal humerus fractures: Usually managed conservatively in adolescents unless significantly displaced 1
- Clavicle fractures: Common but typically from direct impact 6, 1
Critical Clinical Pitfalls
The most important caveat: Non-contrast MRI frequently shows false-positive findings in young athletes, particularly for SLAP tears 3. A case report demonstrates a 13-year-old football player whose initial MRI suggested a SLAP tear, nearly leading to unnecessary surgery, when the actual diagnosis was a coracoid growth plate fracture 3.
Examination Priorities for This Age Group
Focus your physical exam on:
- Physeal tenderness: Palpate the proximal humeral physis and coracoid process—pain here takes priority over adult-pattern diagnoses 4
- Apprehension and relocation tests: Primary assessment for anterior instability 4
- Load and shift test: Evaluates multidirectional instability 4
- Pain with rotational movements: Suggests physeal involvement 4
Diagnostic Approach
Start with plain radiographs as they remain the preferred initial imaging modality for acute shoulder pain 6. Obtain bilateral comparison views, as subtle physeal injuries may only be apparent when compared to the contralateral side 3.
The sensitivity and specificity of physical examination maneuvers are variable, making the mechanism of injury and patient history particularly important 7. Radiographs and even MRIs are frequently negative in soft tissue problems in young athletes, underscoring the importance of thorough clinical examination 7.
If advanced imaging is needed, recognize that contrast-enhanced MRI is superior to non-contrast MRI for labral pathology, but clinical findings remain more reliable than imaging alone 7, 3.
Age-Specific Considerations
Adolescent shoulder injuries differ fundamentally from adult patterns because: