Diagnosis of cruciate ligament injury using single contrast arthrography.

To evaluate the accuracy of arthrography for assessing the status of the anterior cruciate ligament (ACL), 212 arthrograms from 212 knees in 205 consecutive patients undergoing single contrast arthrography and subsequent arthroscopy or arthrotomy were reviewed. Criteria for evaluation of the ACL included the clarity of its radiographic appearance as well as the anterior laxity of the knee as seen on manual stress views. Of the 111 knees having intact ACLs at surgery, 98 (88%) were evaluated correctly by arthrography. Of the 101 knees having a damaged ACL, 85 were read as torn or attenuated on the arthrogram. When the torn and attenuated ligaments were considered separately, accuracy was decreased. Of the 87 ligaments actually torn, 68 (78%) were read as torn and 9 (10%) as attenuated. Of the 14 actually attenuated, 5 (36%) were read as attenuated and 3 (21%) as torn. Of 114 arthrograms read as intact, 98 (86%) were correct. Of 77 arthrograms read as torn, 68 (88%), were correct. Of 21 arthrograms read as attenuated, 5 (24%) were correct. Of 114 torn medial menisci, 112 (98%) were correctly diagnosed, as were 38 (69%) of 55 torn lateral menisci. Sixteen of the 17 missed lateral meniscus tears were in knees with torn medial menisci. Single contrast arthrography is, therefore, highly accurate in distinguishing intact from damaged ACLs. The distinction between torn and attenuated ligaments, however, is not valuable.