From the Guidelines
For a suspected Salter-Harris type I fracture of the distal fibula physis in a 14-year-old male with a lateral ankle injury where the growth plate is not visible on initial x-ray, I recommend immobilization with a short leg cast or removable walking boot for 3-4 weeks. Initial management should include rest, ice, compression, and elevation (RICE protocol) as suggested by general principles of fracture management 1. The patient should avoid weight-bearing for the first week, then progress to partial weight-bearing as tolerated.
Key Considerations
- Follow-up imaging with repeat x-rays in 7-10 days is essential, as growth plate fractures may become more visible after initial swelling subsides 1.
- If symptoms persist or worsen, consider advanced imaging such as MRI to better visualize the physis, as it is the reference standard for ligamentous injury and assessment of stability 1.
- These fractures typically heal well with conservative management, but proper treatment is crucial to prevent growth disturbances.
- The physis (growth plate) is weaker than surrounding ligaments in adolescents, making it vulnerable to injury during ankle trauma 1.
- Even though the initial x-ray appears normal, clinical suspicion based on point tenderness over the growth plate warrants treatment as a fracture until proven otherwise, as growth plate injuries can lead to long-term complications if missed or improperly managed.
Imaging Protocols
- Radiographs are indicated in patients who meet OAR criteria as the initial imaging study, with typical radiographic protocols including three standard views: anteroposterior, lateral, and mortise views to include the base of the fifth metatarsal bone distal to the tuberosity 1.
- Weight-bearing radiographs, if possible, provide important information, particularly with fractures of uncertain stability 1.
- Special scenarios that warrant special mention and additional views include axial Harris-Beath view, Broden view, and bicycle spoke injuries in children 1.
From the Research
Diagnosis of Suspected Salter-Harris Type 1 Fracture
The diagnosis of a suspected Salter-Harris type 1 fracture of the distal fibula physis in a 14-year-old male with a lateral ankle injury, where the growth plate is not visible on initial X-ray, can be challenging.
- The clinical diagnosis of Salter-Harris type 1 fracture of the distal fibula (SH1DF) is often incorrect, with studies showing that the majority of cases are actually ligamentous sprains and/or bony contusions 2, 3, 4.
- Magnetic Resonance Imaging (MRI) is a useful tool in diagnosing SH1DF, as it can detect occult growth plate fractures and other injuries such as ligamentous sprains and bony contusions 3, 4.
- The proportion of SH1DF in children with radiograph-negative lateral ankle injuries is low, ranging from 0-3% in recent series 5.
- Other injuries, such as anterior talofibular ligament (ATFL) injuries and osteochondral avulsions, are more common in children with lateral ankle injuries 5.
Imaging and Diagnosis
- Initial X-rays may not show the growth plate, and further imaging such as MRI may be necessary to confirm the diagnosis 3, 4.
- MRI can detect SH1DF, as well as other injuries such as ligamentous sprains and bony contusions, and can help guide treatment decisions 3, 4.
- The use of MRI in diagnosing SH1DF can help reduce the risk of overtreatment and improve patient outcomes 3.
Treatment and Management
- Treatment of SH1DF typically involves immobilization and orthopedic follow-up, but the use of MRI can help guide treatment decisions and reduce the risk of overtreatment 3.
- Children with radiograph-negative lateral ankle injuries can be managed with a removable brace and allowed to return to activities as tolerated, regardless of whether an SH1DF is present or not 3.