Summary

The incidence rate of ACL-R per 1000 athlete events is 2 to 6 times higher in female professional athletes compared to male professional athletes in Sweden.

Abstract

Introduction

Few studies have looked at the nationwide incidence rate (IR) of anterior cruciate ligament reconstruction (ACL-R) in higher level athletes in different sports simultaneously. To better understand the nature of ACL-R within different sports in Sweden, we aimed to study the IR of ACL-R in high-performance athletes in the six of the most common sports in the Swedish National Knee Ligament Registry (SNKLR) : soccer, ice hockey, basketball, handball, floorball, and alpine sports.

Methods

Patient data from the SNKLR, between January 2005 and December 2020, was linked to team rosters and event data of the two highest divisions of soccer, ice hockey, basketball, handball, floorball, and the highest levels of alpine sports. Professional athletes, 15–40 years of age, who sustained an anterior cruciate ligament (ACL) injury and later underwent ACL-R during seasons 2005–2020 while playing in the two highest divisions in team sports or participating in official International Ski and Snowboard Federations were included. Outcomes were evaluated based on athletes sex, division and sport. The IR of ACL-R was calculated as injuries per 1000 athlete events (AE) and as injuries per 100000 athlete-seasons .

Results

Results identified a total of 1014 ACL-R in 932 athletes during the study period. Female basketball athletes had 5.6 times higher IR of ACL-R than male basketball athletes (IR 1.238 vs 0.221 per 1000 AE, incidence rate ratio [IRR] 5.595, 95% CI 3.370–9.289, p<0.001). In soccer, handball, floorball, and alpine sports the IR of ACL-R per 1000 AE was 2 to 3 times higher for females than for males. In professional ice hockey however, there was no significant difference in the IR of ACL-R between females and males (IR 0.080 vs 0.081 per 1000 AE, IRR 0.982, 95% CI 0.388–2.485, p=0.844). There was a significant higher IR of ACL-R in female handball athletes compared to female soccer athletes (IR 1.705 vs 1.161 per 1000 AE, IRR 1.469, 95% CI 1.163–1.857, p=0.001). However, this was not the case for male handball athletes compared to male soccer athletes (IR 0.585 vs 0.516 per 1000 AE, IRR 1.134, 95% CI 0.836–1.539, p=0.466). On the other hand, the IR of ACL-R per 1000 AE in handball for both female and male athletes was significantly higher compared to floorball, ice hockey, basketball and alpine sports.

Conclusion

This is a nationwide study looking at the total IR of ACL-R in six different knee-strenuous sports during a same study period. The IR of ACL-R per 1000 AE in handball, soccer, basketball, floorball, and alpine sports were significantly higher in female athletes compared to male athletes. However, there was no significant difference in IR of ACL-R per 1000 AE in elite ice hockey between females and males.