2015 ISAKOS Biennial Congress Paper #0

Patient and Surgical Risk Factors Associated With Not Achieving A Minimal Important Change In KOOS Function in Sports and Recreation and Knee-Related Quality of Life Subscales After ACL Reconstruction

Janina Kaarre, MD, MSc, Pittsburgh UNITED STATES
Rebecca Simonson SWEDEN
Viktor Ris , Göteborg SWEDEN
Thorkell Snaebjörnsson, MD, Gothenburg SWEDEN
James J. Irrgang, PT, PhD, FAPTA, Pittsburgh, Pennsylvania UNITED STATES
Volker Musahl, MD, Prof., Pittsburgh, Pennsylvania UNITED STATES
Kristian Samuelsson, Prof, MD, PhD, MSc, Mölndal, Västra Götalands län SWEDEN
Eric Hamrin Senorski, PT, PhD, MSc, Västra Frölunda SWEDEN
Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy University of Gothenburg, Mölndal/Gothenburgh , SWEDEN

FDA Status Not Applicable

Summary: Clinicians should be aware of both modifiable and non-modifiable risk factors for not achieving a MIC after ACL-R and thus, should adjust treatment and establish realistic expectations for the patient.

Abstract:

Objectives: To investigate factors associated with not achieving a minimal important change (MIC) in the Knee injury and Osteoarthritis Outcome Score (KOOS) Function, Sports, and Recreational Activities (Sport/Rec), and Knee-Related Quality of Life (QoL) subscales 1 year after anterior cruciate ligament reconstruction (ACL-R).

Methods

This study used data from the Swedish National Knee Ligament Registry. Multivariable logistic regression models were used to determine factors associated with not achieving a MIC. The KOOS subscales Sport/Rec and QoL were dichotomized (not achieving/achieving MIC; the MICs for the Sport/Rec and QoL subscales were 12.1 and 18.3 respectively) and combined into one single variable (Sport & QoL).

Results

Of 16,131 included patients 44% did not achieve the MIC for the combined Sport/Rec and QoL subscales 1 year after ACL-R. Older patients (OR 0.91, 0.88-0.94; p<0.0001), males (OR 0.93, 0.87-0.99; p=0.034) and patients receiving hamstring tendon autograft ACL-R (OR 0.70, 0.60-0.81; p<0.0001) had decreased odds of not achieving the MIC 1 year after ACL-R compared to younger patients, females and patients receiving patellar tendon autograft. In addition, patients with cartilage injuries (OR 1.17, 1.09-1.27; p<0.0001) and higher pre-operative KOOS Sport/Rec and QoL scores (OR 1.34, 1.31-1.36; p<0.0001) had increased odds of not achieving the MIC.

Conclusion

Females, younger patients, and patients with higher pre-operative Sport/Rec and QoL KOOS scores, and cartilage injuries, are less likely to benefit from ACL-R and subsequently, have a lower probability for improved Sport/Rec and QoL scores after ACL-R. In addition, graft choice may also be associated with the risk of not achieving the MIC.