Currently proposed risk factors after episode 5
| Non-modifiable risk factors | |
| History of HMI | Yes: five episodes in 5 months |
| Age>23/24 | Yes: age 26 |
| Black African/Caribbean ethnicity | Yes |
| Past ACL/major knee injury history | No: as per definition in study but Gd 3 MCL 18 months prior |
| Past osteitis pubis | No: as per definition in study but bilateral Sportsman's hernia repair 8 years prior |
| Modifiable hamstring muscle properties | |
| Bilateral hamstring strength asymmetry>8% (REFS) | No (injured side strength>uninjured side) |
| Concentric H/Q ratio<0.66 (REFS) | Yes (0.58 vs 0.62) |
| Optimum angle (REFS) | 23° (vs 24°) |
HMI, hamstring muscle injury.