MR arthrography of anterior cruciate ligament reconstruction grafts.

Objective: Our objective was to determine the accuracy of MR arthrography for identification of tears of anterior cruciate ligament reconstruction grafts and for detection of localized anterior arthrofibrosis and impingement.

Materials And Methods: We retrospectively identified 27 patients (mean age, 31 years; range, 18-45 years) with anterior cruciate ligament reconstruction who had undergone MR arthrography followed by arthroscopy within 1 year. Three radiologists independently reviewed the MR arthrograms for the presence or absence of graft tear, localized anterior arthrofibrosis, and impingement.

Results: Graft tears were identified with 100% sensitivity by all three reviewers with specificities of 100%, 89%, and 94%. Localized anterior arthrofibrosis was identified with 100% sensitivity by all reviewers, with specificities of 79%, 71%, and 38%. Impingement was detected with sensitivities and specificities of 83% and 100%, 83% and 52%, and 33% and 90% by the three reviewers, respectively. Interobserver agreement was almost perfect for detection of graft tear (kappa = 0.83, 0.92, and 0.83), was fair to moderate for detection of localized anterior arthrofibrosis (kappa = 0.50, 0.32, and 0.22), and was slight to fair for detection of impingement (kappa = 0.40, 0.08, and 0.35).

Conclusion: MR arthrography can accurately depict the presence of anterior cruciate ligament graft tears. Localized anterior arthrofibrosis and graft impingement were less accurately detected and showed greater observer variability.