Background: Our aim was to examine the association between an expert clinician's impression of symptomatic meniscal tears and subsequent MRI in the context of middle-aged and older adults with knee pain.
Methods: Patients older than 45 were eligible for this IRB-approved substudy if they had knee pain, had not undergone MRI and saw one of two orthopaedic surgeons experienced in the diagnosis of meniscal tear. The surgeon rated their confidence that the patient's symptoms were due to meniscal tear. The patient subsequently had a 1.5 or 3.0 T MRI within 6 months. We examined the association between presence of meniscal tear on MRI and the surgeon's confidence that the knee pain was due to meniscal tear using a χ(2) test for trend.
Results: Of 84 eligible patients, 63% were female, with a mean age of 64 years and a mean BMI of 27. The surgeon was confident that symptoms emanated from a tear among 39%. The prevalence of meniscal tear on MRI overall was 74%. Among subjects whose surgeon indicated high confidence that symptoms were due to meniscal tear, the prevalence was 80% (95% CI 63-90%). Similarly, the prevalence was 87% (95% CI 62-96%) among those whose surgeon had medium confidence and 64% (95% CI 48-77%) among those whose surgeon had low confidence (p = 0.12).
Conclusion: Meniscal tears were frequently found on MRI even when an expert clinician was confident that a patient's knee symptoms were not due to a meniscal tear, indicating that providers should use MRI sparingly and cautiously to confirm or rule out the attribution of knee pain to meniscal tear.
Keywords: Diagnosis; Knee pain; MRI; Meniscal tear.