Salter-Harris Fracture

What is a Salter-Harris fracture?

A Salter-Harris fracture is an injury to the physis, or growth plate, in skeletally immature individuals. Because the physis guides longitudinal bone growth, these injuries require early recognition to prevent growth arrest or limb deformity. Physeal injuries account for approximately 15%–30% of pediatric bony injuries, most commonly involving the distal radius, distal tibia, and distal femur.

Clinicians use the Salter-Harris classification to stratify these injuries based on how they involve the metaphysis (the neck of the bone), the physis, and the epiphysis (the rounded end of the bone). This system helps predict the risk of future growth disturbances. Identifying the specific fracture pattern is essential for determining whether the bone can be managed with a simple cast or requires surgical intervention.

What causes a Salter-Harris fracture?

These fractures occur when mechanical forces (such as shearing, tension, or compression) exceed the strength of the cartilaginous physis. In a growing child, this growth plate is naturally weaker than the surrounding ligaments and bone. Torsional injuries during sports or a fall onto an outstretched hand (FOOSH) apply differential stress that can cause the plate to separate. Commonly affected areas, like the distal radius and distal tibia, are vulnerable during periods of rapid growth, when the physis is relatively weak. Direct blows to a joint can also drive a fracture line through the cartilage and into the adjacent bony structures.

Salter-Harris fractures are classified by how the fracture line involves the physis, metaphysis, and epiphysis. Type I passes through the physis only. Type II passes through the physis and metaphysis, and is the most common type. Type III passes through the physis and epiphysis into the joint. Type IV crosses the metaphysis, physis, and epiphysis. Type V is a crush injury of the physis that may be radiographically occult and has the highest risk of growth arrest.

What are the signs and symptoms of a Salter-Harris fracture?

These fractures typically present with localized tenderness directly over the growth plate following an acute injury. Swelling and joint effusion (fluid buildup within the joint) are common, along with a significantly limited active range of motion. Weight-bearing becomes difficult or impossible, particularly when an injury involves a lower-extremity physis such as the distal tibia.

While neurovascular compromise is rare, providers must carefully monitor for changes in pulses or sensation. Deformity may be subtle, requiring a comparison of the injured limb with the contralateral side to detect minor angulation. Repeat examination and follow-up imaging may be needed to monitor alignment and detect displacement.

How is a Salter-Harris fracture diagnosed?

Diagnosis begins with orthogonal radiographs, which include true anteroposterior and lateral views of the affected joint. Clinicians may request oblique views or even radiographs of the opposite limb to identify subtle physeal widening. Identifying whether the fracture extends into the epiphysis or joint surface is critical for classification and management.

A Type I Salter-Harris fracture can be particularly challenging to diagnose because the physis may separate without creating visible bone fragments. If radiographs appear normal but clinical suspicion remains high, the injury may be treated clinically with follow-up radiographs. CT or MRI can be used when the extent of injury is unclear or surgical planning is needed.

How is a Salter-Harris fracture treated?

Initial management prioritizes immobilization, activity restriction, and non-weight-bearing when a lower-extremity injury requires it. Most Type I and Type II injuries respond well to closed reduction (repositioning the bone without surgery) followed by a period of casting. However, an epiphysis fracture that extends into the joint (Types III and IV) often requires anatomic reduction and internal fixation to restore the smooth articular surface.

Type V injuries, which involve a crushing of the physis, carry the highest risk of growth arrest and require long-term monitoring. Follow-up radiographs may be needed to monitor healing and detect premature growth plate closure, especially of the distal tibial and femoral growth plates. If premature closure occurs, a corrective osteotomy (surgical bone cutting) may be needed to realign the limb.

What are the most important facts to know about a Salter-Harris fracture?

• A Salter-Harris fracture is a fracture involving the physis (growth plate) of a long bone in a skeletally immature patient.
• These injuries most often result from acute trauma, such as a fall, sports injury, or twisting mechanism that places shear, tension, or compression forces across the growth plate.
• The Salter-Harris classification (Types I–V) categorizes fractures based on whether the fracture line involves the physis alone or extends into the metaphysis and/or epiphysis, helping estimate the risk of growth disturbance.
• Patients typically present with localized pain, swelling, and tenderness over the growth plate after trauma, with a limited range of motion and possible difficulty bearing weight when the lower extremity is involved.
• Diagnosis is primarily made with plain radiographs (anteroposterior and lateral views) of the affected region, with clinical diagnosis, repeat radiographs, or advanced imaging (MRI or CT) only necessary in certain cases.
• Management depends on fracture type and displacement, and includes immobilization after closed reduction, internal fixation, and long-term follow-up due to the high risk of growth arrest.