Structural pathology is not related to patientreported pain and function in patients undergoing meniscal surgery

Background The relationship between meniscal tears and other joint pathologies with patient-reported symptoms is not clear. We investigated associations between structural knee pathologies identified at surgery with preoperative knee pain and function in patients undergoing arthroscopic meniscal surgery. Methods This study included 443 patients from the Knee Arthroscopy Cohort Southern Denmark (KACS), a prospective cohort following patients 18 years or older undergoing arthroscopic meniscal surgery at 4 hospitals between 1 February 2013 and 31 January 2014. Patient-reported outcomes, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), were obtained by online questionnaires prior to surgery. Knee pathology was assessed by the operating surgeons using a modified version of the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification of meniscal tears questionnaire, supplemented with information extracted from surgery reports. Following hypothesis-driven preselection of candidate variables, backward elimination regressions were performed to investigate associations between patient-reported outcomes and structural knee pathologies. Results Regression models only explained a small proportion of the variability in self-reported pain and function (adjusted R-2 = 0.10-0.12) and this association was mainly driven by age, gender and body mass index. Conclusions Specific meniscal pathology and other structural joint pathologies found at meniscal surgery were not associated with preoperative self-reported pain and function in patients with meniscal tears questioning inferences made about a direct relationship between these. Our findings question the role of arthroscopic surgery to address structural pathology as a means to improve patient-reported outcomes in patients having surgery for a meniscal tear.