Pediatric Supracondylar Humerus Fracture: A Complete Clinical Guide
Supracondylar humerus fractures are the most common elbow fractures in children, accounting for up to 80% of all pediatric elbow injuries requiring hospitalization. These fractures typically occur between the ages of 5 and 8 and are often the result of a simple fall—yet they carry significant risks if not managed properly. This evidence-based guide synthesizes current best practices from leading orthopedic institutions (including Boston Children’s Hospital and the Royal Children’s Hospital Melbourne) to provide clear, actionable information for both clinicians and families.
What Is a Supracondylar Humerus Fracture?
A supracondylar humerus fracture is a break in the distal humerus just above the growth plate (physis), in the thin metaphyseal bone that has not yet fully ossified. This area is biomechanically weak, making it vulnerable to injury during hyperextension.
The overwhelming majority (97–99%) are extension-type fractures, caused by a FOOSH injury—Fall On an OutStretched Hand. Common scenarios include falls from playground equipment (monkey bars, scooters, skateboards), or sports collisions. Less than 3% are flexion-type fractures, usually from direct impact to a flexed elbow.
Epidemiology and Risk Factors
- Peak age: 5–8 years
- Gender: More common in boys (M:F ≈ 1.5:1)
- Arm affected: Non-dominant arm in 60% of cases
- Seasonality: Higher incidence in spring and summer due to increased outdoor activity
Children in this age group have ligamentous laxity and immature bone architecture, which predisposes them to this injury during routine play.
Clinical Presentation
Children typically present with:
- Acute pain and refusal to use the arm
- Rapid swelling around the elbow
- Visible deformity—often an “S-shaped” contour in displaced fractures
- “Skin puckering” (a dimple over the antecubital fossa), indicating proximal fragment penetration through the brachialis muscle
Red Flags Requiring Immediate Orthopedic Consultation
- Absent radial pulse or cool/pale hand (“pulseless hand”)
- Neurological deficits (especially inability to make an “OK” sign—suggesting anterior interosseous nerve palsy)
- Open wound or severe anterior bruising
- Signs of compartment syndrome: severe pain, tight forearm, pain on passive finger extension
Radiographic Evaluation
Obtain true AP and lateral X-rays of the distal humerus (not just the elbow joint). Key radiographic signs include:
- Anterior humeral line: On a true lateral view, a line drawn along the anterior cortex of the humerus should intersect the middle third of the capitellum. Posterior displacement = fracture.
- Fat pad sign: Elevation of the anterior and/or posterior fat pads suggests occult fracture, especially in non-displaced injuries.
- Baumann’s angle: On AP view, the angle between the humeral shaft axis and the capitellar physis. Normal = 64°–82°. Decreased angle suggests varus malalignment.
Gartland Classification System
The modified Gartland classification guides treatment decisions and prognosis:
| Type | Description | Management |
|---|---|---|
| I | Non-displaced or minimally displaced (<2 mm); intact periosteum | Long-arm cast or backslab × 3–4 weeks |
| II | Displaced with intact posterior cortex hinge; anterior humeral line misses capitellum | Closed reduction ± percutaneous pinning |
| III | Completely displaced; no cortical contact; high risk of neurovascular injury | Urgent closed reduction + percutaneous pinning |
| IV | Multidirectional instability (unstable in both flexion and extension) | Surgical fixation required |
Treatment Strategies
Non-Operative Management (Gartland Type I)
- Immobilization in a long-arm backslab at 70°–90° elbow flexion
- Elevation for 48 hours to minimize swelling
- Pain control with acetaminophen or ibuprofen
- Follow-up with primary care in 3 weeks; repeat X-ray not routinely needed
Important: The cast should extend from the axilla to the metacarpophalangeal (MCP) joints to prevent loss of reduction. Avoid short or flimsy splints.
Operative Management (Gartland Type II–IV)
Indications for surgery include displacement, neurovascular compromise, or inability to maintain reduction. The gold standard is closed reduction with percutaneous K-wire fixation under fluoroscopic guidance.
K-Wire Configuration: Lateral vs. Crossed
Two main techniques exist for percutaneous pinning:
| Technique | Advantages | Disadvantages | Evidence-Based Recommendation |
|---|---|---|---|
| Lateral-only K-wires (2–3 wires) | • Lower risk of iatrogenic ulnar nerve injury • Simpler technique • Comparable stability in most Type II/III fractures |
• Slightly higher risk of loss of reduction in severely comminuted fractures | First-line choice per AAOS guidelines and multiple RCTs (e.g., Kocher et al., JBJS 2007) |
| Crossed medial + lateral K-wires | • Superior biomechanical stability • Preferred in Type III/IV or unstable reductions |
• 3–5× higher risk of ulnar nerve injury • Requires precise medial pin placement |
Use only when lateral pins fail to achieve stability; employ mini-open medial approach to protect the ulnar nerve |
Best Practice: Always confirm reduction and pin placement with both AP and lateral fluoroscopy. Post-reduction, the elbow should be immobilized in ≤90° flexion to avoid compartment syndrome.
Postoperative and Cast Care
- K-wires are removed in clinic at 3–4 weeks
- Elbow remains immobilized in a long-arm cast for 3–4 weeks total
- Encourage active motion of fingers, wrist, and shoulder during immobilization
- No routine physical therapy is needed—children regain motion naturally through play
Parents should be advised to elevate the limb for the first 48 hours and monitor for signs of swelling, numbness, or color changes.
Potential Complications
| Complication | Incidence | Prevention & Management |
|---|---|---|
| Cubitus varus (“gunstock deformity”) | 3–5% (down from 58% with modern pinning) | Avoid coronal plane malalignment; corrective osteotomy if severe and symptomatic |
| Neurological injury | 6–19% (mostly transient neuropraxia) | Anterior interosseous nerve (AIN) most commonly affected; >90% resolve within 3 months |
| Vascular injury / “pink pulseless hand” | 10–20% in Type III fractures | Emergent reduction; if perfusion doesn’t return, consider vascular exploration |
| Compartment syndrome → Volkmann’s contracture | 0.1–0.3% | Immobilize elbow at ≤90° flexion; monitor for pain, tightness, and passive stretch pain |
Follow-Up and Recovery Timeline
- 1 week: First post-op visit with X-ray to assess alignment
- 3–4 weeks: Cast and pin removal
- 4–6 weeks: Gradual return of elbow motion through normal activity
- 6–12 weeks: Full return to non-contact activities; contact sports only after physician clearance
Most children regain full or near-full range of motion without formal therapy. Persistent stiffness beyond 8 weeks warrants orthopedic re-evaluation.
Frequently Asked Questions (FAQ)
Q: Does my child need physical therapy after the cast is removed?
A: In most uncomplicated cases—no. High-quality studies (Schmale et al., JBJS 2014) show no functional benefit from formal physical therapy. Encourage gentle use in daily activities like eating, drawing, and playing. Full motion typically returns within 4–6 weeks.
Q: How long until my child can return to sports?
A: Avoid contact sports, playgrounds, and high-risk activities for 6–12 weeks. Return is based on X-ray healing, pain-free motion, and physician clearance—not just cast removal.
Q: What if the elbow looks crooked after healing?
A: Mild cubitus varus is often cosmetic with minimal functional impact. However, severe deformity may cause tardy ulnar nerve palsy or affect self-esteem. Discuss with your orthopedic surgeon—corrective osteotomy is an option near skeletal maturity.
Q: Are K-wires safe? Will they hurt my child?
A: K-wires are temporary and removed in the clinic without anesthesia. Infection risk is low (<2%). Lateral-only pins significantly reduce nerve injury risk. Post-op pain is usually well-controlled with oral medications.
Key Takeaways for Clinicians
- Always perform and document a thorough neurovascular exam.
- Immobilize the elbow at ≤90° flexion to minimize compartment pressure.
- Prefer lateral-only K-wires unless instability demands crossed configuration.
- Refer Gartland Type II with coronal deformity or any Type III fracture immediately.
- Educate families on red flags: increasing pain, numbness, cool/pale hand.
Conclusion
Supracondylar humerus fractures are common but potentially serious pediatric injuries. With prompt recognition, accurate classification, and appropriate management—especially timely pinning for displaced fractures—excellent outcomes are the norm. Modern techniques have dramatically reduced complications like cubitus varus and Volkmann’s contracture. Collaboration between emergency providers, orthopedic surgeons, and families ensures the safest, most effective care.
References
- American Academy of Orthopaedic Surgeons. (2011). Clinical Practice Guideline: The Treatment of Pediatric Supracondylar Humerus Fractures.
- Kocher, M. S., et al. (2007). Lateral entry compared with crossed pin fixation for supracondylar humerus fractures in children. Journal of Bone and Joint Surgery, 89(4), 790–795.
- Schmale, G. A., et al. (2014). Lack of benefit of physical therapy on function following supracondylar humeral fracture: a randomized controlled trial. JBJS, 96(11), 944–950.
- Vaquero-Picado, A., et al. (2018). Management of supracondylar fractures of the humerus in children. EFORT Open Reviews, 3(10), 526–540.
- Boston Children’s Hospital Orthopedics. (2019). Supracondylar Humerus Fracture: Take-Home Instructions.
- Royal Children’s Hospital Melbourne. (2023). Clinical Practice Guidelines: Supracondylar Fracture of the Humerus.
- Brubacher, J. W., & Dodds, S. D. (2008). Pediatric supracondylar fractures of the distal humerus. Current Reviews in Musculoskeletal Medicine, 1(3–4), 190–196.