RAD blog

Why do we measure strength after a hamstring strain injury?

Strength testing is a useful clinical tool in the first half of your rehab when performed in long-lever positions. 

After injury we prefer to assess hamstring strength with a hand-held dynamometer (HHD) in outer range positions.

Whiteley et al. 2018 identified that testing strength in an outer range position offered more relevant information than mid-range and inner-range positions. 

As a rule of thumb we expect your outer range strength to approach 75% of the un-injured leg during the first half of your rehab. 

Outer range strength testing appears consistent across the literature. 

Wollin et al. 2016 assessed isometric hamstring strength at 30 degrees of knee flexion (and 45 degrees on hip flexion) using an externally fixed device. 

This position is difficult to replicate in private practice – however we try to replicate 30 degrees of knee flexion when assessing hamstring strength using the Force Decks.  

Crema et al. 2017 used isometric knee flexion force in their clinical examination to try and identify acute injuries involving the intramuscular tendon. 

Another clue in identifying these injuries may be a reduction in isometric strength at 15 degrees of knee flexion.

Take Home: 

• Strength testing is important – but so is the position you assess hamstring strength
• Outer range strength appears the best strength measure to guide/progress rehab
• Similar to flexibility – we see greater strength improvements in the first half of rehab

Do you have a Hamstring injury that needs to be assessed in Ballarat? Click through to our Physiotherapy page to find an appointment time:

https://radcentre.com.au/physiotherapy-and-injury-rehabilitation

References: 

• Whiteley, R., et al. (2018). Clinical implications from daily physiotherapy examination of 131 acute hamstring injuries and their association with running speed and rehabilitation progression. British Journal of Sports Medicine. 52(5): 303-310. 
• Wollin, M., et al. (2016). Reliability of externally fixed dynamometry hamstring strength testing in elite youth football players. Journal of Science and Medicine in Sport. 19(1): 93-96.
• Crema, M. D., et al. (2017). Can a Clinical Examination Demonstrate Intramuscular Tendon Involvement in Acute Hamstring Injuries? Orthopaedic Journal of Sports Medicine. 5(10): 1-8.

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