What is the diagnosis for a patient with an MRI report indicating bone marrow edema of the distal fibula, a linear region of low signal extending from the physis (growth plate) distally, and an undisplaced fracture involving the lateral malleolus with a suspected Salter-Harris type 1 component?

From the Guidelines

The patient's diagnosis is most likely a Salter-Harris type 1 fracture, which is a fracture that involves the growth plate but without displacement, as evidenced by the MRI report indicating bone marrow edema of the distal fibula and an undisplaced fracture involving the lateral malleolus with a suspected Salter-Harris type 1 component. The MRI findings, including the linear region of low signal extending from the physis distally, are consistent with this diagnosis 1. Key features of this injury include:

• Bone marrow edema in the distal fibula
• Undisplaced fracture involving the lateral malleolus
• Suspected Salter-Harris type 1 component, which involves the growth plate
• No evidence of ligament damage, tendon injuries, or joint effusion
• Intact ankle joint alignment The management of this injury typically involves immobilization with a cast or boot for 4-6 weeks to allow proper healing, followed by gradual rehabilitation 1. It is essential to monitor for any growth disturbances, which can occasionally occur with physeal injuries, and follow-up imaging may be necessary to ensure proper healing 1. Weight-bearing restrictions would likely be recommended initially, with gradual return to activities as healing progresses. The use of MRI in this case is particularly important, as it allows for high-resolution evaluation of the tendons and ligaments, and can help exclude other types of injuries, such as ligamentous injuries or tendon abnormalities 1.

From the Research

Diagnosis of Ankle Injury

The diagnosis for a patient with an MRI report indicating bone marrow edema of the distal fibula, a linear region of low signal extending from the physis (growth plate) distally, and an undisplaced fracture involving the lateral malleolus with a suspected Salter-Harris type 1 component can be considered based on the following points:

• The presence of bone marrow edema and a linear region of low signal on MRI may indicate a fracture or stress injury to the distal fibula 2.
• The suspected Salter-Harris type 1 component suggests a fracture involving the growth plate, which is a common injury in pediatric patients 3, 2.
• However, a study found that the clinical diagnosis of Salter-Harris type 1 fracture of the distal fibula (SH1DF) was incorrect in 100% of cases, and instead, MRI identified ligamentous sprains and/or bony contusions in almost 90% of patients 2.
• Other possible diagnoses to consider include osteonecrosis, which can occur after a Salter-Harris type 1 fracture, although this is rare 3.
• The presence of an undisplaced fracture involving the lateral malleolus may require further evaluation to determine the best course of treatment, which may include nonsurgical or surgical management 4, 5.

Possible Diagnoses

Possible diagnoses for this patient include:

• Salter-Harris type 1 fracture of the distal fibula
• Ligamentous sprain
• Bony contusion
• Osteonecrosis
• Undisplaced fracture involving the lateral malleolus

Imaging and Treatment

Imaging studies, such as MRI, can help guide the diagnosis and treatment of this patient 2, 4.

• MRI can help identify the extent of the injury and guide treatment decisions.
• Treatment may include nonsurgical management, such as immobilization and physical therapy, or surgical management, such as open reduction and internal fixation 4, 5.