MR IMAGING OF ANTERIOR CRUCIATE LIGAMENT INJURIES - HOSPITAL BASED STUDY

Objective: To determine the MR imaging patterns of anterior cruciate ligament injuries Study Design: Descriptive study Place and Duration of Study: Armed Forces Institute of Radiology and Imaging Rawalpindi, from July 2013 to May 2014. Patients and Methods: Patients referred to MRI dept, of AFIRI with history of traumatic or non traumatic knee pain were included in the study. Age range was 16-60yrs.  Patients > 60yrs of age and with known diseases like tumors, AV malformations, degenerative changes etc were excluded from the study. Total 81 patients were included in the study through non-probability consecutive sampling. Results: The patients in this study had a mean age of 30.10 ± 9.017 years having minimum age of 16 years and maximum age of 56 years. There were 70 (88.6%) male patients and 9 (11.4%) female patients in the study. The mechanism injury showed that majority 59 (74.7%) of the patients had a traumatic injury. According to the clinical symptoms almost all the patients presented with knee pain and only 2 (2.5%) patients had instability of knee. According to the MRI findings the most common ACL finding was inconspicuous ACL which was found in 21 (26.6%) patients followed by ACL contusion which was noted in 10 (12.7%) patients. MRI findings of 8 (10.1%) patients had combination of findings like Inconspicuous ACL at femoral attachment and posterior bowing of ACL fibers. Similarly 3 (3.8%) patients had findings of Inconspicuous ACL and fluid signals at ACL femoral attachment(empty notch sign). It was noted that in 36 (45.6%) patients there was negative MRI examination. Conclusion: The ACL ligament is a very important ligament structurally and because it is so frequently injured. Imaging, and in particular, MRI has allowed a much more accurate assessment of ACL injuries and other conditions affecting the ACL as well as associated injuries.When evaluating for ACL insufficiency, radiologists must be able to recognize primary and secondary signs on imaging to make a diagnosis as they are helpful in determining the success of primary repairs. However, improved imaging with newer MR equipment and  imaging techniques is required in our setup to improve accuracy in diagnosis of partial tears. Keywords : Anterior cruciate ligament, knee injury