Inter- and Intraobserver Reliability Between Orthopaedic Surgeons for Reparability of the Anterior Cruciate Ligament Using MRI

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction is the standard of care for patients after an ACL tear, as poor historical outcomes were observed after primary ACL repair. Certain subgroups of patients, however, have been shown to have outcomes equivalent to reconstruction after undergoing ACL repair and therefore may benefit from the potential advantages offered by avoiding reconstruction. It is important to accurately and consistently identify and indicate these candidates for ACL repair. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the inter- and intraobserver reliability of magnetic resonance imaging (MRI) evaluation for the reparability of ACL tears and to identify imaging factors that may lead to surgeon uncertainty or disagreement in decision making. Our hypothesis was that the orthopaedic surgeons surveyed would not be able to reliably agree on the reparability of an ACL using MRI scans alone. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: We administered 2 surveys to 6 fellowship-trained orthopaedic sports medicine surgeons. Each surgeon reviewed preoperative MRI scans for 20 patients and answered a series of questions, ultimately determining whether they would choose an ACL reconstruction or repair for the patient based on the imaging alone. The same survey was repeated 6 weeks later. Kappa values for inter- and intraobserver reliability of their decision making were then calculated. RESULTS: The average kappa for interobserver reliability in the 2 surveys was 0.22, and the average kappa for intraobserver reliability was 0.34. Interobserver reliability among the surgeons in this group was poor to moderate; intraobserver reliability was slightly better. The choice for ACL repair was significantly correlated with proximal tear locations (r = 0.854; P < .001), good-quality ACL tissue remnant (r = 0.929; P < .001), and how many surgeons believed that the tear only involved a single bundle (r = 0.590; P = .006). CONCLUSION: The surgeons surveyed in this study did not consistently agree on candidates for ACL repair using MRI alone.