Background: Arthroscopic knee surgery including partial meniscectomy & meniscal repair are of the world's most performed surgical procedures. Magnetic Resonance arthrography is the cornerstone imaging modality in evaluating postoperative symptomatic patients.
Objective: This study aimed to evaluate the diagnostic value of conventional MR compared to MR arthrography in the diagnosis of recurrent meniscal tear.
Subjects and methods: Our prospective cross-sectional study included 20 patients with postoperative meniscus surgery admitted to Orthopedic Department, Suez Canal University Hospital through the period from April 2020 to September 2021. Results: In the meniscus surgery group (total 20 patients), 6 studied cases (30%) were treated with meniscal repair, 13 studied cases (65%) had meniscectomy and one patient (5%) had meniscal transplants. Conventional MRI showed 77% sensitivity, 58% specificity and 67.5% accuracy in the meniscal surgeries group. MRI and MRA showed high agreement (K= 0.66) in meniscal transplant and meniscectomy less than 25%, while MRI has a low agreement (K=0.1 &0.5) with MRA in meniscal repair and meniscectomy more than 25%.
Conclusions:Conventional MRI alone has low sensitivity and specificity in the assessment of recurrent tears in post-meniscal surgeries where MR arthrography is essential in the detection of recurrent meniscal tears in cases of meniscal repair and partial meniscectomy more than 25%. However, when meniscus resection is minimal (less than 25%) conventional MRI is usually enough for diagnosis.