Would a computed tomography (CT) scan be helpful in evaluating a patient with chronic right ankle pain, degenerative changes at the tibiotalar joint, and a history of remote fractures of the lateral and medial malleoli, given that an X-ray has already been performed and a magnetic resonance imaging (MRI) scan has been ordered?

From the Guidelines

An MRI is the better choice for evaluating the patient's ankle pain, as it is superior for evaluating soft tissue structures, cartilage damage, ligament injuries, and osteochondral defects, which are likely contributing to the patient's ongoing pain. While CT would provide excellent bone detail to further assess the healed malleolar fractures and bony changes, MRI is more appropriate in this case due to its ability to characterize degenerative changes at the tibiotalar joint and a possible osteochondral defect in the lateral talar dome, as seen on the X-ray report 1. The current plan to proceed with an MRI, continue ankle brace use, and follow up with the orthopedic specialist is appropriate, as MRI can also detect bone marrow edema, which might explain the patient's ongoing pain 1. Additionally, MRI is effective in determining osteochondral injury instability and can be used to stage these lesions preoperatively, with accuracy of 81% 1. The orthopedist can then determine if additional imaging like CT is needed after reviewing the MRI results, providing a comprehensive evaluation while avoiding unnecessary radiation exposure from a CT scan that might not provide the needed soft tissue information. Key points to consider include:

• MRI is superior for evaluating soft tissue structures, cartilage damage, ligament injuries, and osteochondral defects
• CT may be considered if additional bone detail is needed, but MRI is the better initial choice
• The current plan to proceed with an MRI and follow up with the orthopedic specialist is appropriate
• MRI can detect bone marrow edema, which might explain the patient's ongoing pain
• The orthopedist can determine if additional imaging like CT is needed after reviewing the MRI results, as suggested by the American College of Radiology appropriateness criteria for chronic ankle pain 1.

From the Research

Ankle Pain and Imaging Studies

• The patient's X-ray report indicates signs of old injuries and developing arthritis, with findings such as a healed fracture of the lateral malleolus, mild marginal spurring, and subcortical cysts 2.
• An MRI has been ordered to further evaluate the patient's ankle pain, which is likely due to degenerative changes at the tibiotalar joint and subcortical lucency in the lateral talar dome 2.

CT Scan vs. MRI

• A CT scan may be helpful in evaluating bony abnormalities associated with tendon injuries, but MRI is generally preferred due to its superior soft tissue contrast resolution and multiplanar capabilities 3.
• CT-arthrography can be used as a further diagnostic approach in cases where MRI is contraindicated or unclear findings are present 2.

Ankle Brace and Follow-up

• The patient has been advised to wear an ankle brace to reduce mechanical ankle instability, which can contribute to chronic ankle instability and degenerative changes 4.
• Follow-up with an orthopedic doctor is recommended to monitor the patient's condition and adjust treatment as necessary.

Imaging Studies for Ankle Pathologies

• MRI is effective in diagnosing various ankle pathologies, including osseous and osteochondral injuries, ligamentous injuries, and tendon pathology 5.
• SPECT-CT has shown to be feasible in foot and ankle surgery, particularly in complex cases with diagnostic uncertainty, and can have a high impact on final treatment decision 6.