Overview
Definition:
Sprains involve ligamentous injuries, while growth plate injuries specifically affect the physis, the region of bone responsible for longitudinal growth in children and adolescents
The Salter-Harris classification is crucial for categorizing these physeal fractures based on their relationship to the physis and epiphysis.
Epidemiology:
Growth plate fractures account for 15-30% of all pediatric fractures
They are most common in children aged 10-16 years, with boys being more frequently affected
The distal radius, distal tibia, and proximal humerus are common sites.
Clinical Significance:
Accurate classification of growth plate injuries is paramount for determining appropriate management and predicting long-term outcomes
Mismanagement can lead to premature physeal closure, limb length discrepancies, and angular deformities, significantly impacting a child's functional status.
Salter Harris Classification
Type I:
Fracture through the physis only
Often difficult to diagnose radiographically
diagnosis may rely on clinical suspicion and tenderness over the physis
Can be diagnosed by displacement of the epiphysis from the diaphysis.
Type Ii:
Fracture through the physis and the metaphysis, sparing the epiphysis
This is the most common type (approximately 75% of cases)
Radiographically, a triangular fragment of metaphysis is seen along with the epiphysis.
Type Iii:
Fracture through the physis and the epiphysis, extending into the joint surface
This type occurs when the physis is fused partially
Common in older children with ossified epiphyses
Requires careful reduction to restore joint congruity.
Type Iv:
Fracture line crosses the metaphysis, physis, and epiphysis
This type involves all three components
Requires surgical reduction and fixation to ensure accurate alignment and prevent physeal bar formation.
Type V:
A crush injury to the physis
This is the rarest and most ominous type
Often difficult to visualize on initial radiographs, diagnosis is typically made retrospectively if growth arrest occurs
High risk of premature physeal closure.
Clinical Presentation
Symptoms:
Acute onset of pain at the affected site
Swelling and tenderness localized to the joint or bone
Inability to bear weight or move the affected limb
A visible deformity may be present in some cases.
Signs:
Point tenderness over the physis or surrounding ligaments
Localized swelling and ecchymosis
Range of motion may be limited due to pain
Crepitus may be palpable during attempted movement
Assessment for neurovascular compromise is essential.
Diagnostic Criteria:
Diagnosis relies on a combination of a thorough history of injury, physical examination findings, and radiographic assessment
Radiographs should include at least two views (AP and lateral) of the injured area, including the joint above and below the suspected injury.
Diagnostic Approach
History Taking:
Mechanism of injury: direct blow, fall, twisting injury
Age of the child: crucial for understanding physeal status (open vs
closed)
Previous injuries or medical conditions affecting bone health
Symptoms of pain, swelling, and functional limitation.
Physical Examination:
Inspect for swelling, deformity, and ecchymosis
Palpate for point tenderness, especially over the physis
Assess range of motion actively and passively
Evaluate distal neurovascular status (pulses, sensation, motor function)
Compare with the contralateral limb.
Investigations:
Plain radiography: Initial imaging of choice, often with contralateral comparison views
If plain radiographs are inconclusive but suspicion is high, stress radiographs or MRI may be considered to evaluate ligamentous integrity or subtle physeal injuries
CT scan may be helpful for complex intra-articular fractures
Ultrasound can sometimes visualize physeal separation in type I injuries.
Differential Diagnosis:
Simple sprain (ligamentous injury without physeal involvement)
Fracture of the metaphysis or epiphysis without physeal involvement
Musculoskeletal contusion
Referred pain
Osteomyelitis (less common with acute trauma presentation).
Management
Initial Management:
RICE protocol: Rest, Ice, Compression, Elevation
Immobilization with a splint or cast to provide comfort and prevent further injury
Analgesia: Non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen as appropriate for pain control
Avoid aggressive manipulation of deformed limbs without adequate imaging and planning.
Medical Management:
Pain management with oral analgesics
Tetanus prophylaxis if open fracture is suspected
Antibiotics are generally not indicated for closed Salter-Harris fractures unless there is significant soft tissue compromise or contamination.
Surgical Management:
Indications for surgery include significantly displaced fractures (especially Type III and IV), intra-articular involvement requiring anatomical reduction, Type V injuries, or failure to achieve acceptable closed reduction
Techniques include percutaneous pinning, screws, or plates for fixation
Open reduction may be necessary for complex injuries.
Supportive Care:
Close monitoring for neurovascular status, especially after reduction and immobilization
Follow-up radiographs to assess healing and alignment
Physiotherapy may be required for regaining range of motion and strength, particularly after surgical intervention or if stiffness develops.
Complications
Early Complications:
Neurovascular compromise (e.g., compartment syndrome)
Skin necrosis or infection (if open fracture)
Displacement of fracture fragments after initial treatment.
Late Complications:
Premature physeal closure leading to limb length discrepancy or angular deformity
Growth arrest lines
Joint stiffness and arthritis
Chronic pain
Malunion or nonunion.
Prevention Strategies:
Accurate diagnosis and appropriate management based on Salter-Harris classification
Careful surgical technique if indicated, with precise anatomical reduction
Avoiding forceful manipulation of physeal fractures
Close radiographic follow-up
Early recognition and management of complications.
Prognosis
Factors Affecting Prognosis:
Salter-Harris type (Type I and II generally have good prognosis
Type IV and V have poorer prognoses)
Age of the child (younger children have greater growth potential to compensate for minor deformities)
Degree of displacement and intra-articular involvement
Accuracy of reduction and stability of fixation
Presence of premature physeal closure.
Outcomes:
Most Type I and II injuries, when managed appropriately, have excellent long-term outcomes with minimal to no growth disturbance
Type III and IV injuries can have good outcomes with accurate reduction but carry a higher risk of complications
Type V injuries have a poor prognosis for normal growth.
Follow Up:
Regular clinical and radiographic follow-up is essential until skeletal maturity is achieved
Serial radiographs may be needed to monitor for evidence of premature physeal closure or angular deformity
Consultation with a pediatric orthopedic surgeon is recommended for all growth plate injuries, especially Types III-V.
Key Points
Exam Focus:
Remember the Salter-Harris classification (I-V) and their respective anatomical locations relative to the physis, epiphysis, and metaphysis
Type II is the most common
Type V is the least common and most ominous due to crush injury to the physis
Radiographic evaluation is key, and comparison views are often helpful.
Clinical Pearls:
In a child with a limp and tenderness over a long bone's end, always consider a growth plate injury even if initial radiographs are normal (especially for Type I injuries)
Early surgical intervention for displaced Type III and IV fractures is crucial to prevent angular deformities and joint incongruity.
Common Mistakes:
Misinterpreting subtle Type I fractures on radiographs
Underestimating the potential for growth disturbance in Type IV and V injuries
Inadequate reduction of intra-articular fragments in Type III fractures
Failing to compare with the contralateral limb when suspecting subtle injuries.