Summary of a review of risk factors for the first-time hamstring strain injury and recurrent hamstring strain injury in sport.
Who
71,324 athletes; 8,319 total hamstring strain injuries including 967 recurrent injuries. 179 potential risk factors analyzed
Design
Systematic review and meta-analysis of 78 studies.
Outcome measures/tests
- index (first-time injury during a period of time)
- recurrent hamstring strain injury (HSI)
Main results
Non-modifiable risk factors:
- older age (based on the results from 19 studies)
- history of HSI (the highest risk for within the same season), ACL injry, knee injury, calf strain injury, or ankle ligament injury
- position played a role in American football, rugby, Gaelic football and cricket. Positions with more running had greater risk of index HSI.
- international travel (in cricket)
Modifiable risk factors for index HSI:
- hamstring muscle-tendon unit stiffness and bicept femoris fascicle length
- reduced hamstring strength and strength endurance
- reduced single leg hop for distance
- decreased trunk muscle and increased gluteus medius electromyographic activity during sprinting/running
- trunk and hamstring motor control (3 studies)
- increase in high-speed running exposure
- increased in thoracis side-bending during running
Modifiable risk factors for recurrent HSI:
decreased active knee extension just after return to play
reduced hamstring strength and strength endurance
No increase in risk for HSI in relation to:
- athlete weight and biceps femoris or glueal muscles size
- quadricept strain or chronic groin pathology, osteitis pubis
- eccentric hamstring strength on Nordic hamstring exercise
- hight and power output of countermovement jump
- flexibility, mobility and range of motion
- aerobic, YoYo, 40m sprinting and agility tests
Conflicting relation for:
- decreased hip extension
- decreased ankle dorsiflexion
- gluteus maximus electromyographic activity in sprinting and running
- reduced between-game recovery
- increased congestion in game schedule
- level of competition
- MRI finding of intratendinous injury, intramuscular tendon disruption
Take home message
Original article
Green B, Bourne MN, van Dyk N, Pizzari T. Recalibrating the risk of hamstring strain injury (HSI)-A 2020 systematic review and meta-analysis of risk factors for index and recurrent HSI in sport. British Journal of Sports Medicine. 2020 Apr 15.