In the previous blog on hamstring injuries, we discussed how the type and structure of injury play a pivotal role in determining effective rehabilitation, you can read about hamstring tendon injuriesToday, our focus shifts to the intra-tendinous subtype, specifically the 3c type injuries according to the British Athletics Muscle Injury Classification score. We will explore how these injuries heal and discuss the implications and associated risks when returning to sport


Lynch, Tierney Hamstring Injuries:

Last week, Richmond’s forward Tom Lynch returned to play after missing 8-9 weeks due to a significant hamstring injury behind his knee needing surgical repair. This week, Scotland’s Kieran Tierney also suffered a significant hamstring injury that required him being stretchered off during the Euro Tournament in Germany. This injury marks his third in six months, an  absence of over 80 days due to injuries between October 2023 and February 2024 


A key feature in these tendon-based injuries is a significantly high recurrence rate. Up to 33%, if return to sport has occurred prematurely. 


The extensive time off is primarily due to tendon’s slower healing properties compared to muscles. Tendons have reduced blood supply, which delays the formation of scar tissue needed to bridge damaged fibers. 


Early Phases of Hamstring Injury:

Within the first 2 weeks of these injuries, we observe increased inflammatory processes to initiate early scar formation. Following this, over the next 1-2 months, we see a thickened and immature scar forming with disorganized collagen. 


Final Phase of Hamstring Injury:

The final phase is known as the remodeling phase. Maturation of the scar begins and develops from 6-8 weeks post injury. It can last for up to 1 year and beyond. It is in this phase we see a thickening of the scar tissue gaining compliance, becoming more rigid to hold the muscle back together. The maturation of tissue commences after the 10-week mark. Achieving peak thickness and stiffness at approximately 6 months post injury. However, after 2 years the scar may structurally never be the same as normal tissue. 


Throughout the above healing process and timelines, its important we are engaging in specific, targeted and appropriate exercise rehab. This assists regaining appropriate principles within the muscle to execute our tasks required for our chose sport/event. In Kieran & Tom’s cases, they need/have been diligent and consistent with their work in the gym to improve their strength, pliability and flexibility of their hamstring (as well as other areas). As well as undertaking a return to run program that involves high speed running, change of direction and reactive components.  


Lastly, If you are an athlete or regular fitness enthusiast experiencing recurrent hamstring strains and are lost as to why. Perhaps there is something amiss with your diagnosis and / or rehabilitation plan. Get in touch with the team at CSSM to put you on the right path, with a plan to improve, whatever your goal.  


About the author

CSSM physiotherapist Peter Stath believes a strong and healthy body maintains a healthy mind, which allows us to perform and work to the best of our ability.

Peter is a strength and conditioning enthusiast with a unique understanding of the demands of high level competition and performance.  Having previously worked within the National Premier League Victoria (soccer) as well as part of the medical team for Futsal Victoria at their National Championships, he has a passion for treating all aspects of musculoskeletal or sporting pain with a particular interest in shoulders, hips, knees and ankles.

He is also a great advocate for the involvement of children and adolescents in sport, helping them develop healthy habits as they grow.



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