Pihl, K, Ensor, J, Peat, G, Englund, M, Lohmander, S, Jørgensen, U, Nissen, N, Fristed, JV and Thorlund, JB (2020) Wild-goose chase, no predictable patient subgroups who benefit from meniscal surgery: patient-reported outcomes of 641 patients 1 year after surgery. British Journal of Sports Medicine, 54 (1). ISSN 0306-3674

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Despite absence of evidence of a clinical benefit of arthroscopic partial meniscectomy (APM), many surgeons claim that subgroups of patients benefit from APM.

We developed a prognostic model predicting change in patient-reported outcome 1 year following arthroscopic meniscal surgery to identify such subgroups.

We included 641 patients (age 48.7 years (SD 13), 56% men) undergoing arthroscopic meniscal surgery from the Knee Arthroscopy Cohort Southern Denmark. 18 preoperative factors identified from literature and/or orthopaedic surgeons (patient demographics, medical history, symptom onset and duration, knee-related symptoms, etc) were combined in a multivariable linear regression model. The outcome was change in Knee injury and Osteoarthritis Outcome Score (KOOS4) (average score of 4 of 5 KOOS subscales excluding the activities of daily living subscale) from presurgery to 52 weeks after surgery. A positive KOOS4 change score constitutes improvement. Prognostic performance was assessed using R2 statistics and calibration plots and was internally validated by adjusting for optimism using 1000 bootstrap samples.

Patients improved on average 18.6 (SD 19.7, range -38.0 to 87.8) in KOOS4. The strongest prognostic factors for improvement were (1) no previous meniscal surgery on index knee and (2) more severe preoperative knee-related symptoms. The model’s overall predictive performance was low (apparent R2=0.162, optimism adjusted R2=0.080) and it showed poor calibration (calibration-in-the-large=0.205, calibration slope=0.772).

Despite combining a large number of preoperative factors presumed clinically relevant, change in patient-reported outcome 1 year following meniscal surgery was not predictable. This essentially quashes the existence of ‘subgroups’ with certain characteristics having a particularly favourable outcome after meniscal surgery.

Trial registration number NCT01871272.

Item Type: Article
Additional Information: This is the accepted author manuscript (AAM). The final published version (version of record) is available online via British Association of Sport and Excercise Medicine at http://dx.doi.org/10.1136/bjsports-2018-100321 - please refer to any applicable terms of use of the publisher.
Uncontrolled Keywords: arthroscopy; knee; meniscus; patient-reported outcomes; prognosis.
Subjects: R Medicine > RC Internal medicine > RC1200 Sports Medicine
Divisions: Faculty of Medicine and Health Sciences > Primary Care Health Sciences
Depositing User: Symplectic
Date Deposited: 14 Jun 2019 15:16
Last Modified: 22 Mar 2021 12:32
URI: https://eprints.keele.ac.uk/id/eprint/6493

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