ORIGINAL RESEARCH n MUSCULOSKELETAL IMAGING Radiology: Volume 264: Number 2—August 2012 n radiology.rsna.org 531 Short-term Clinical Importance of Osseous Injuries Diagnosed at MR Imaging in Patients with Anterior Cruciate Ligament Tear 1 Richard Kijowski, MD Mamadou L. Sanogo, MD Kenneth S. Lee, MD Alejandro Muñoz del Río, PhD Tim A. McGuine, PhD Geoffrey S. Baer, MD Ben K. Graf, MD Arthur A. De Smet, MD Purpose: To determine the association between osseous injuries and short-term clinical outcome in patients with anterior cruciate ligament (ACL) tear. Materials and Methods: The retrospective study was performed with institutional review board approval, and the requirement to obtain in- formed consent was waived. The study group consisted of 114 patients (57 male and 57 female patients with a mean age of 26.1 and 25.1 years, respectively) with ACL tear who underwent magnetic resonance (MR) imaging and ACL reconstruction surgery and who filled out In- ternational Knee Documentation Committee (IKDC) knee evaluation questionnaires before and 1 year after surgery. All MR images were independently reviewed by two radi- ologists to determine the presence of a cortical depression fracture on each surface of the knee joint. Bone marrow edema volume was quantified by using segmentation soft- ware. Correlation coefficients were used to determine the association between bone marrow edema volume and IKDC score. A multivariate analysis model was used to compare IKDC scores in patients without fracture, pa- tients with a single fracture, and patients with multiple fractures. Results: There was no significant association between total bone marrow edema volume and preoperative or postoperative IKDC score (P = .32 and P = .91, respectively). The mean preoperative and postoperative IKDC scores were 53.4 6 18.6 and 93.0 6 5.0, respectively, for patients with- out fracture, 54.8 6 13.6 and 87.3 6 10.8 for patients with a single fracture, and 53.1 6 17.2 and 83.4 6 12.7 for patients with multiple fractures. Patients with single and multiple fractures had similar (P = .91) preoperative IKDC scores but significantly lower (P , .001) postoper- ative IKDC scores compared to patients without fracture. Conclusion: Cortical depression fractures in patients with ACL tear are associated with decreased clinical outcome scores 1 year after ACL reconstruction surgery. q RSNA, 2012 Supplemental material: http://radiology.rsna.org/lookup /suppl/doi:10.1148/radiol.12112171/-/DC1 1 From the Departments of Radiology (R.K., M.L.S., K.S.L., A.M.d.R., A.A.D.S.) and Orthopedic Surgery (T.A.M., G.S.B., B.K.G.), University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Clinical Science Center- E3/311, Madison, WI 53792-3252. Received October 11, 2011; revision requested November 12; revision received January 18, 2012; accepted February 8; final version ac- cepted March 6. Address correspondence to R.K. (e-mail: r.kijowski@hosp.wisc.edu). q RSNA, 2012 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights.