MRI of the ankle: Effect on diagnostic confidence and patient management

OBJECTIVE. The purpose of our study was to quantify the impact that MRI of the ankle has on a surgeon's diagnosis and diagnostic confidence and on patient management. SUBJECTS AND METHODS. A prospective controlled observational study was performed with 91 consecutive referrals (53 males, 38 females; age range, 13-76 years; mean age, 40.6 years) from a single orthopedic foot and ankle surgeon to a regional teaching hospital for ankle MRI. Measurements of diagnostic confidence using a visual analogue scale (VAS) were made both before and after the MRI examination in each case. Proposed management was also recorded before imaging and then with benefit of the MRI result. Finally, the surgeon provided a subjective statement regarding the perceived usefulness of the MRI examination when the patient was subsequently reviewed in the clinic. RESULTS. There was a significant overall change in diagnostic confidence in 65 (71%) cases. The number of diagnoses reduced from an average per patient of 2.3 (95% CI, 2.09-2.44) to 1.2 (95% CI, 1.05-1.39), and in 157 (69%) of all diagnoses entertained, there was a significant change in the confidence with which they were considered after imaging. Management plans changed in 32 (35%) of the patients, and in 31% of those patients for whom plans were changed, a less invasive plan was adopted. Overall, the surgeon thought that understanding of the patient's disease had either depended on MRI or had been substantially improved by it in 60 (66%) cases. CONCLUSION. MRI of the ankle influences clinicians' diagnoses and management plans.