Pediatric Proximal Humerus Fractures

Pediatric Proximal Humerus Fractures

Prepared by Dr. Taha Furkan YAGCI

Overview

• Relatively uncommon injuries in the pediatric population (approximately  2% of pediatric fractures)
• High remodeling potential due to an active proximal humeral physis
• Management depends primarily on patient age, displacement, and remaining growth potential

Anatomy

• The proximal humerus is a key component of shoulder motion and stability
• Radiographic appearance of secondary ossification centers
• Proximal humeral epiphysis at 6 months
• The greater tuberosity appears at 1-3 years
• Lesser tuberosity appears at 4-5 years
• Deforming forces:
• Pectoralis major and deltoid  → medial and anterior displacement of the shaft
• Supraspinatus, infraspinatus, teres minor → external rotation of the greater tuberosity (proximal fragment)
• Pediatric-specific considerations:
• A thick periosteum may block closed reduction
• The long head of the biceps tendon is the most common interposed structure
• The proximal humeral physis contributes ~80% of humeral longitudinal growth
• Physeal closure begins in mid-adolescence

Epidemiology

• The annual incidence is approximately 30 per 100,000 children
• Male predominance (x3), peak in early adolescence
• Common mechanisms:
• Direct trauma (a fall directly onto the shoulder or a blunt force or strike)
• Indirect fall onto an outstretched hand, with the arm abducted and externally rotated
• Special considerations:
• Neonates and infants: consider birth-related injury
• history of forced obstetric maneuvers, high gestational weight, and breech presentation 
• Little League shoulder (LLS):
• Fracture of the proximal humeral growth plate that occurs from overthrowing in baseball players aged 11 to 14 years.
• X-rays: physeal widening and metaphyseal changes, not an actual fracture
• Pathologic fractures may occur in the setting of benign bone lesions
• unicameral bone cysts (UBC), nonossifying fibromas, aneurysmal bone cysts (ABC)
• Child abuse: in a child younger than 2 years should raise concern

Classification

• Neer–Horowitz classification (most commonly used)
• Type I: < 5mm displacement
• Type II: < 1/3 shaft width displacement
• Type III: 1/3–2/3 shaft width displacement
• Type IV: > 2/3 shaft width displacement
• Salter–Harris classification:
• Applicable for physeal injuries
• Less useful for metaphyseal fractures

Clinical Presentation

• Pain, swelling, and localized tenderness in the shoulder
• Limited shoulder motion or refusal to move the arm
• Many patients prefer holding the arm internally rotated against the body.
• Visible deformity in displaced fractures
• Neurovascular assessment:
• Check distal pulses
• Check brachial plexus nerve function, especially the axillary nerve.
• Associated injuries:
• In patients with high-energy injuries, fractures of the proximal humerus can be associated with dislocations of the glenohumeral joint.
• Neonatal: clavicle fracture, injury of the brachial plexus

Imaging

• Plain radiographs are the diagnostic standard
• AP shoulder view
• Scapular Y view
• Axillary view (or Velpeau view if abduction is not tolerated)
• CT scan
• Reserved for complex fractures or fracture-dislocations, intra-articular extension
• Used selectively due to radiation concerns
• MRI
• Indicated when a pathological fracture is suspected
• Ultrasound
• Useful in neonates
• Operator dependent

Treatment

• High remodeling capacity favors nonoperative management in most cases
• Decision-making factors:
• Patient age
• Degree of displacement and angulation
• Skeletal maturity
• Acceptable criteria for non-operative management
• <10 years old = any degree of angulation
• 10-12 years old = < 60-75° of angulation
• >12 years old =  < 45° of angulation or 2/3 displacement

Nonoperative Management

• Indications:
• Non-displaced or minimally displaced fractures
• Younger patients with significant growth remaining
• Methods:
• Sling and swathe
• Shoulder immobilizer
• Coaptation splint
• Duration:
• Typically 3–4 weeks
• Outcomes:
• Excellent functional recovery
• Rare need for secondary surgical intervention
• Neonatal: a safety pin is all that is needed to immobilize the arm by attaching a small stockinette-like sling or pinning the sleeve to the shirt.

Operative Management

• There is no absolute criteria with regard to the amount of displacement or angulation that requires surgical management.
• Closed reduction +/- fixation
• Unacceptable criteria for non-operative management as described above
• Open reduction internal fixation
• The deltopectoral approach is commonly used
• Failed closed reduction or soft tissue interposition
• Neurovascular compromise
• Open fracture
• Risk factors associated with surgery:
• Older age
• Greater injury severity

Surgical Techniques

• Closed reduction and percutaneous pinning
• Most commonly used technique
• Short operative time
• Low blood loss
• Elastic stable intramedullary nailing (ESIN)
• Preserves soft tissues
• Allows relative stability and remodeling
• Plate fixation
• Rarely indicated
• Reserved for severe deformity in near-skeletal maturity

Outcomes

• Overall prognosis is excellent
• Nonoperative treatment:
• High rates of full range of motion
• Low pain rates at follow-up
• Operative treatment:
• Good functional outcomes
• Higher-grade fractures are associated with:
• Increased residual angulation
• Limb length discrepancy
• Motion limitation

Complications

• Rare
• Nonoperative:
• Mild malunion
• Transient stiffness
• Operative:
• Pin tract infection (most common)
• Malunion
• Rare neurovascular injury
• Pin migration

Key Points

• Most pediatric proximal humerus fractures can be treated nonoperatively.
• Remodeling potential decreases with age.
• For severely displaced Neer and Horwitz grade III and IV fractures of the proximal humerus in the adolescent, there is no consensus on optimal treatment.
• Both operative and nonoperative treatments yield favorable outcomes.

References:

1-    Kim AE, Chi H, Swarup I. Proximal Humerus Fractures in the Pediatric Population. Curr Rev Musculoskelet Med. 2021 Dec;14(6):413-420. doi: 10.1007/s12178-021-09725-4. Epub 2021 Oct 28. PMID: 34709578; PMCID: PMC8733110.

2-    Popkin, C. A., Levine, W. N., & Ahmad, C. S. (2015). Evaluation and management of pediatric proximal humerus fractures. The Journal of the American Academy of Orthopaedic Surgeons, 23(2), 77–86. https://doi.org/10.5435/JAAOS-D-14-00033