This edition of the FastFact profiles research from two of our 49 FMCE’s. It looks at the influence of injury mechanism and quadriceps strength on a player’s confidence about returning to play after an ACL reconstruction.1
The aim of this study was to evaluate the influence of quadriceps strength symmetry on a player’s psychological readiness to return to play (RTP) following an ACL reconstruction (ACLR). A total of 78 female patients completed strength testing and the Injury–Psychological Readiness to Return to Sport (I-PRRS) scale. Isometric quadriceps strength was measured using a motor-driven dynamometer. Linear regression analysis was used to assess the relationship between the I-PRRS and other variables, including quads strength and injury mechanism. Patients were aged between 13 and 30 years of age and participated in either ‘level 1 sport’ (sport with frequent pivoting or cutting such as football, soccer, volleyball or lacrosse) or level 2 sport (sport with less frequent pivoting or cutting such as softball, tennis or dance). Patients who met the above criteria were included in the study regardless of their mechanism of injury, graft type or presence of any coexisting pathologies (for example meniscal tears).
The study’s key finding was that there was a significant linear relationship between quadriceps strength symmetry and the I-PRRS score in patients who experienced a non-contact injury (n = 55; P = 0.01; R2 = 0.24). There was no such relationship among those who had sustained a contact injury mechanism (n = 23; P = 0.97; R2 = 0.01). Based on these results it would appear that greater quadriceps strength symmetry is associated with greater psychological readiness to RTP in those who have a non-contact ACL injury.
Greater quadriceps symmetry has been linked to been linked to higher rates of RTP and has been shown to protect against a secondary ACL injury. It is also known that female athletes have lower rates of psychological readiness to RTP after an ACLR compared with male athletes. The results of this study further highlight the importance of quadriceps strength as a measure of rehabilitation and illustrates the impact that it may have on a player’s confidence about RTP. Clinicians should consider carefully assessing this metric.
As with any study there are a number of limitations that should be illustrated. The cohort included athletes from a range of sports, not just football, and as a result may not be generalisable to all football players. Furthermore, the sample size was small and the study did not include male players. The cross-sectional study design and variability regarding surgical treatment, post-surgical rehabilitation and the timing of testing are also potential limitations.
1. Della Villa F, Straub RK, Mandelbaum B, Powers CM. Confidence to Return to Play After Anterior Cruciate Ligament Reconstruction Is Influenced by Quadriceps Strength Symmetry and Injury Mechanism. Sports Health. February 2021. doi:10.1177/1941738120976377