Clinical examination vs. MRI: evaluation of diagnostic accuracy in detecting ACL and meniscal injuries in comparison to arthroscopy.

Background: To compare the diagnostic accuracy of clinical examination and MRI in evaluation of meniscal and ACL injuries using arthroscopic findings as reference standard.

Material/methods: A total of 51 patients with traumatic knee injuries were identified and prospectively followed up with clinical examination, MRI and arthroscopy. Clinical examination and MRI findings were compared with arthroscopic findings. Sensitivity, specificity, PPV, NPV and diagnostic accuracy were calculated with statistical analysis.

Results: Out of 24 patients with arthroscopic evidence of medial meniscal injury, clinical examination and MRI correctly identified 20 and 18 patients, respectively. Clinical examination was characterized by better sensitivity and specificity with regard to diagnosis of medial meniscal tear. On arthroscopy, lateral meniscal tear was present in 13 patients; clinical examination and MRI both identified 8 of them correctly. Similarly, out of 9 patients with arthroscopic evidence of ACL tear, clinical examination and MRI correctly identified 7 and 8 patients, respectively. There were only marginal differences in sensitivity and specificity of clinical examination and MRI in diagnosis of lateral meniscal and ACL injury.

Conclusions: Careful clinical examination is much better than MRI with regard to the diagnosis of medial meniscus injury and is as reliable as MRI with regard to diagnosis of lateral meniscus injury and ACL tears. MRI should be used to rule out such injuries rather than to diagnose them.