What is your diagnosis?

Displaced Salter Harris I fracture of the distal femur. Salter-Harris fractures of the distal femur account for only about 2% of all Salter Harris fractures [1]. 

• Pearl: There are five classification types (prevalence): 

• I: Through the epiphyseal plate (5%)

• II: Through the epiphyseal plate and metaphysis (75%)

• III: Through the epiphyseal plate and epiphysis (10%)

• IV: Through the metaphysis, epiphyseal plate, and epiphysis (10%)

• V: Compression of the epiphyseal plate (rare) [2]

What is your management in the ED? Do I need to consult Orthopaedics?

In general, non-displaced type I fractures can be managed conservatively in the ED with splinting and outpatient Orthopaedic follow up. These require a high level of suspicion as x-rays may appear negative. 

In this case there is significant displacement with shortening and this patient requires emergent orthopaedic consultation and urgent surgical fixation. A displaced type I fracture should be treated as a knee dislocation and distal pulses should be checked. Have a high index of suspicion for neurovascular injury such as a popliteal injury. The risk for compartment syndrome increases with displaced fractures. 

• Pearl: A displaced type I fracture is often unstable and typically requires fixation.

What are the complications?

With the severity of displacement in this case, neurovascular complications are possible and need to be monitored closely. This can be done via recurrent ABI and physical exam, or CTA of the leg. 

Salter-Harris fractures are at risk for long term complications such as leg length discrepancy or growth disturbance. Specifically for distal femur fractures type I fractures have a 36% rate of growth disturbance, type II have a 58% rate, type III have a 49% rate, and type IV have a 64% rate of growth disturbance [1]. 

What is your disposition?

Admission for surgical fixation. This patient required traction to maintain the fracture at length. 

• Pearl: Other fracture type management

• Non-displaced type I and type II: Splint and outpatient follow up

• Type III and IV: Often require ORIF, will need urgent orthopedic follow up

• Type V: EMERGENT orthopaedic consultation due to high risk of growth arrest [2]

What imaging should be obtained?

Plain films of the injured extremity are sufficient. CT or MRI can be obtained if clinically  indicated. 

If there is concern for a vascular injury an ABI can be obtained along with observation and repeat testing. ABI should be > 0.9. Alternatively CTA of the leg can be performed to definitively rule out vascular injury.