MRI technology continues to improve benefiting clinicians searching for serious pathology, but at a cost of identifying non serious pathology which may not be related to a patient’s clinic presentation. Initial imaging studies in the 1990s were conducted in the lumbar spine which identified a high percentage of structural changes including disc herniations and spinal arthritic changes in individuals without pain. Since these early studies were conducted additional research has found similar findings in pain free necks, shoulders, and hips. The high percentage of findings in asymptomatic individuals places a greater emphasis on the patient history and clinical examination to determine the impact of these findings on the patient’s presentation. A recent study shows how important this point is in patients trying to interpret the clinical significance of their knee MRI.
Authors in the journal Skeletal Radiology sought to identify the percentage of MRI findings and pathology in a cohort of individuals without knee pain (Torlasco et al. 2021). Authors imaged 230 knees of 115 pain free individuals (64 female, average age 44 y.o., age range 25-73) and each scan was read by a radiologist to determine the incidence of meniscal tears, arthritis, ligamentous tears, and cartilage injury. They reported 97% of the knees were diagnosed with one of the tissue abnormalities. Specifically, one in three (30%) demonstrated a significant meniscal tear and half were diagnosed with a bone and cartilage abnormality under the knee cap (patellofemoral joint). The authors concluded, “nearly all knees of asymptomatic adults showed abnormalities in at least one knee structure on MRI”.
Patients are encouraged to interpret their MRI findings in comparison to what may be identified in their asymptomatic peers.