KNEE 3-T MR imaging of partial ACL tears: a cadaver study Hanno Steckel Æ Gianluca Vadala Æ Denise Davis Æ Volker Musahl Æ Freddie H. Fu Received: 29 November 2006 / Accepted: 12 March 2007 Ó Springer-Verlag 2007 Abstract Magnetic resonance imaging (MRI) is the most commonly used diagnostic imaging procedure for sus- pected injuries to the anterior cruciate ligament (ACL). However, MRI has less utility for the evaluation of partial ACL tears. The goal of this study was to evaluate the possibility of distinguishing partial ACL tears applying the double bundle concept by dividing the ACL anatomy in the anteromedial (AM) and posterolateral bundle (PL). Six human cadaver knees were used in this laboratory study. The protocol consisted of sagittal, oblique coronal, and oblique sagittal proton-density-weighted fast spin echo sequences. After MRI the AM and the PL bundle were severed to mimic different partial ACL rupture patterns. MRI scanning of each knee was repeated, to record the quantitative parameters tilt and ACL angles and disconti- nuity as a nonquantitative parameter. Three orthopaedic surgeons and two radiologists were enlisted as blinded observers to evaluate the images. The transection patterns could be differentiated by evaluating discontinuity both in the paracoronal and in the sagittal plane. Evaluating the transection patterns, the AM bundle reached a better result in both planes compared to the PL bundle and the parac- oronal plane had a better result in assessing the transection patterns compared to the sagittal plane for the PL bundle. Partial ACL transections could predictably be recognized on oblique sagittal and oblique coronal planes utilizing 3-T MRI technology. This concept allows a more precise description of ACL rupture patterns and might lead to a more distinctive approach for reconstructive surgery. The presurgical planning could be improved by applying a treatment algorithm based on a description of each bundle as intact or ruptured, leading to a reconstruction of the torn and a preservation of the intact bundle. Keywords Anterior cruciate ligament Á Anteromedial bundle Á Posterolateral bundle Á Magnetic resonance imaging Á Rupture patterns Introduction Magnetic resonance imaging (MRI) is the most commonly used diagnostic imaging procedure for suspected injuries to the anterior cruciate ligament (ACL). With an expected sensitivity of 92–100% and specificity of 85–100% it is possible to provide information of the normal ACL anat- omy, tears, and grafts [9, 14, 16, 32]. Since new pulsing sequences, multiplanar imaging, different field strengths, and ultra-thin-slicing have enhanced the image quality and accuracy of the procedure, better anatomic details are provided [3, 7, 15]. Several investigators have shown high accuracy of MRI in the assessment of native ACL and complete ACL tears [4, 16, 17]. However, MRI has less H. Steckel (&) Á G. Vadala Á V. Musahl Á F. H. Fu Department of Orthopaedic Surgery, University of Pittsburgh, 3471 Fifth Avenue, Suite 1011, Pittsburgh, PA 15213, USA e-mail: hanno.steckel@gmail.com H. Steckel Department of Orthopaedic Surgery, University of Go ¨ttingen, Robert-Koch-Straße 40, 37073 Go ¨ttingen, Germany G. Vadala Department of Orthopaedic Surgery, Campus Bio-Medico University, Via E. Longoni 69, 00155 Rome, Italy D. Davis Magnetic Resonance Research Center, University of Pittsburgh, 200 Lothrop Street, Pittsburgh 15213, USA 123 Knee Surg Sports Traumatol Arthrosc DOI 10.1007/s00167-007-0337-5