Summary

This study aimed to describe the Composite Score of Readiness (CSR) as a method providing a single score for RTS tests after ACL reconstruction and analyze how many tests should be included in the final CSR.

Abstract

Introduction

Return-to-sport (RTS) after anterior cruciate ligament (ACL) reconstruction require readable and easy-to-use, holistic indication of an athlete’s readiness-to-play. The injury risk index called Composite Score of Readiness (CSR) may allow for assessing these athletes' functional deficits. It was recommended that RTS testing after ACL reconstruction should incorporate several tests, but it is unclear which are the most appropriate. This study aimed to describe the Composite Score of Readiness (CSR) as

Method

providing a single score for RTS tests after ACL reconstruction and analyze how many tests should be included in the final CSR. When is the CSR accurate - when it is calculated based on a small or large number of tests?

Methods

The study included 65 male football players (age 18-25 years), divided into three groups: Group 1 (ACL) (n=24) - subjects after ACL rupture and reconstruction during previous 2-3 years who passed RTS and were cleared to play; Group 2 (MI) (n=21) - subjects after mild lower limb injury during previous 2-3 years; Group 3 (C) (n=20) - control group without injuries. The CSR was calculated based on five performed tests (Functional Movement Screen (FMS), Tuck Jump Assessment (TJA), Y-balance test (YBT), hop test (HT), isokinetic test (IT)) and expressed as the sum of z-scores. The CRS allows to highlight an athlete’s functional deficits across tests relative to the healthy group. The interpretation of the CSR is as follows: zero represents the group average, any value above zero means that the athlete is better than average, while values below 0 indicate worse performance. Two kinds of CSR indexes were calculated: CSRA-H - for athletes after ACL reconstruction relative to the group of athletes without injuries; CSRM-H - for athletes after mild lower limb injuries relative to the group of athletes without injuries. A multiple stepwise regression model was calculated, and redundant variables were excluded from the model.

Results

CRS calculated from FMS, TJA, YBT, HT and IT tests indicated, that athletes after ACL reconstruction are in functionally worse state than those following mild injuries. CSR that constituted of five or four tests results better differentiated athletes after ACL reconstruction from those after mild injuries, because the difference in CSR value between the groups was higher. For CSR calculated from three tests the difference was lower, and for CSR calculated from two tests the difference was low and not significant. Regression model showed that CSR index calculated from FMS, TJA, YBT, HT and IT including only knee flexors values influenced the final index the most. Data from IT for extension and from H/Q ratio are redundant in regression model, which means that they should be removed from the CSR index calculations.

Conclusion

The CSR is a simple way to differentiate athletes with severe functional deficits following serious injuries like ACL reconstruction from those with only small functional deficits. This difference may be expressed as one index, which is easy for interpretation. CSR should be calculated from more than two tests because it increases its accuracy. Y-balance test, Tuck Jump Assessment and isokinetic test for knee flexors influenced the final CSR index the most, what means that these tests are most indicative for functional deficits related to ACL reconstruction. The CSR index seems to be a useful tool for monitoring of athletes who returned to sport after ACL reconstruction. This method of evaluation may prevent them from ACL re-injury.