From the Guidelines
When a radiologist and a pediatric orthopedic surgeon interpret an ankle MRI differently, with the radiologist diagnosing a Salter-Harris type I growth plate fracture and the pediatric orthopedic surgeon diagnosing a bone bruise, it is recommended to follow the pediatric orthopedic surgeon's assessment. This recommendation is based on the specialized training of pediatric orthopedic surgeons in children's bone injuries and their ability to integrate clinical findings with imaging results, as highlighted in the American College of Radiology's appropriateness criteria for acute trauma to the ankle 1. The treatment approach for a bone bruise, which typically involves rest, ice, compression, elevation (RICE protocol), and possibly non-weight bearing or protected weight bearing for a short period, differs significantly from that of a Salter-Harris fracture, which may require immobilization with a cast for 3-4 weeks and closer follow-up.
Some key points to consider in this situation include:
- The importance of MRI in assessing ligamentous injury and stability, particularly in athletes, as it allows for high-resolution evaluation of tendons and ligaments and distinction between tendinopathy, sprain, and partial or complete tears 1.
- The possibility of ligament and tendon injuries occurring without fracture on radiography, with studies showing that 15% of ligamentous injuries at the syndesmosis in acute ankle injuries on MRI demonstrated no fracture on radiography 1.
- The association between bone bruise and adjacent soft-tissue edema with acute ligamentous injuries and tendon abnormalities in patients with negative radiographs 1.
- The role of MRI in excluding Salter 1 fractures in the pediatric population, which is crucial in avoiding unnecessary immobilization and promoting proper healing 1.
In terms of management, it is essential to consider the pediatric orthopedic surgeon's physical examination findings, such as the location of tenderness, degree of swelling, and stability of the joint, which provide crucial context that complements the imaging results. A follow-up appointment in 2-3 weeks can be requested to ensure proper healing regardless of the exact diagnosis.
From the Research
Interpretation of Ankle MRI by Radiologist and Pediatric Orthopedics Surgeon
- The radiologist diagnoses a Salter-Harris type I growth plate fracture, while the pediatric orthopedics specialist diagnoses a bone bruise.
- According to 2, the Salter-Harris classification of growth plate injuries aids in estimating both the prognosis and the potential for growth disturbance.
- However, studies such as 3 and 4 suggest that lateral ankle injuries without radiographic evidence of a fracture may represent ankle sprains rather than growth plate fractures.
Diagnosis of Salter-Harris Type I Fracture
- 3 found that only 3.0% of children with radiograph-negative lateral ankle injuries had MRI-confirmed Salter-Harris type I fractures of the distal fibula.
- 4 also found that none of the 18 patients with clinically suspected Salter-Harris type I fracture of the distal fibula had evidence of fibular growth plate injury on MR imaging.
- Instead, most patients had evidence of ligamentous sprains and/or bony contusions, as reported in 3 and 4.
Management of Growth Plate Fractures
- 5 emphasizes the importance of understanding the properties of the pediatric skeleton and being sensitive to the psychological and social expectations of patients and their families.
- The provider must remain vigilant for changes in the osseous and soft tissue structures during treatment, as failure to recognize signs of growth interruption and changes in position may lead to functional abnormalities, as noted in 5.
- The diagnosis and treatment of growth plate fractures require a detailed understanding of fracture mechanism and fracture patterns, as well as the potential for growth disturbance, as discussed in 2 and 5.