From the Guidelines
Radiologists might misdiagnose a Salter-Harris type I lateral fracture on MRI because these injuries can be challenging to differentiate from bone bruises, as both conditions show similar signal changes on MRI, particularly increased T2 signal at the growth plate. The key difference lies in interpretation: a true fracture would show complete separation through the physis (growth plate), while a bone bruise presents as edema without disruption of the growth plate architecture 1. The pediatric orthopedic surgeon's assessment of a bone bruise rather than a fracture may be more accurate because orthopedic specialists have more clinical experience with pediatric fracture patterns and can correlate imaging findings with physical examination findings like point tenderness, swelling, and functional limitations.
Some key points to consider in differentiating between Salter-Harris type I fractures and bone bruises include:
- The presence of bone bruise and adjacent soft-tissue edema have shown a higher association with acute ligamentous injuries and tendon abnormalities in patients with negative radiographs 1
- MRI can help exclude Salter 1 fractures in the pediatric population, but its interpretation requires careful consideration of the clinical context and correlation with physical examination findings 1
- Salter-Harris type I fractures are often radiographically occult on standard X-rays, making MRI interpretation more subjective and highlighting the need for a multidisciplinary approach to diagnosis and treatment
The disagreement between the radiologist's and orthopedic surgeon's assessments highlights the importance of collaboration in pediatric injuries, as treatment approaches differ significantly - fractures may require immobilization or even surgical intervention, while bone bruises typically need only activity modification and symptomatic treatment.
From the Research
Radiologist Misdiagnosis of Salter-Harris 1 Lateral Fracture on MRI
- A pediatrics orthopedic surgeon may diagnose a bone bruise, while a radiologist may diagnose a growth plate fracture due to the complexity of interpreting MRI results in skeletally immature children 2, 3.
- Studies have shown that the clinical diagnosis of Salter-Harris type I fractures is often incorrect, with MRI identifying ligamentous sprains and/or bony contusions in almost 90% of cases 2.
- The high false-positive rate of clinically suspected Salter-Harris type I fractures may lead to misdiagnosis by radiologists, highlighting the need for careful interpretation of MRI results 3.
Diagnostic Challenges
- Ultrasound may allow visualization of Salter-Harris type 1 fractures, but its sensitivity and specificity are unknown, making it unreliable for eliminating the diagnosis 4.
- MRI is a more reliable diagnostic tool, but its interpretation requires expertise in pediatric orthopedic injuries to accurately distinguish between growth plate fractures and other injuries such as bone bruises or ligamentous sprains.
Implications for Diagnosis and Treatment
- The misdiagnosis of Salter-Harris type I fractures can have significant implications for treatment, with potential consequences for the child's long-term bone health and athletic career 5.
- A multidisciplinary approach, including collaboration between radiologists, orthopedic surgeons, and physical therapists, is essential for accurate diagnosis and effective management of pediatric orthopedic injuries 5.