Diagnosis: Hamstring Strain
How Hamstring Strain Presents
A hamstring strain is a common traumatic injury that usually occurs during sporting activities.
Depending on the severity of the strain, the symptoms can range from mild discomfort to agonising pain limits weight bearing in the affected leg, making it difficult to stand or walk.
- Sudden pain in the back of the thigh during activities such as running and jumping
- May be accompanied by a popping, snapping or tearing sound
- Swelling a bruising may develop, sometimes a couple of days after the injury
- Depending on the severity, patients may complain of tightness at the back of the thigh when walking or bending over, to severe pain, weakness and inability to extend the knee.
How Hamstring Strain is Diagnosed
Being a common sporting injury, your skilled physiotherapist is well equipped to diagnose for hamstring strain. A positive diagnosis can be formed on the following assessments:
- A full history of the presenting symptoms
- Observation for asymmetry in muscle bulk between limbs, and bruising and swelling on the back of the thigh
- Tenderness, swelling, warmth and pain on palpation of a hamstring muscle. In more severe injuries, there may be a lump or a gap in the muscle bulk, which may indicate a muscle tear
- Assessment of walking and running abilities
- Increased hamstring tightness and pain or increased discomfort on stretching the muscle
- Loss of flexibility in the knee, and decreased range of motion of hip flexion with the leg straight
Causes of Hamstring Strain
Your hamstrings are a group of muscles consisting of the biceps femoris, semitendinosus and semimembranosus. In a hamstring strain, fibres of one or more of these muscles are torn due to a rapid contraction or stretch.
Hamstring Tear (author: Bruce Blaus source: WikiMedia Commons)
There are 3 grades of severity:
- Grade 1: A few fibres in a muscle or tendon are torn (generally not detectable). You’ll feel tightness in the back of your thigh. There might be some slight discomfort with walking but it not be affected. Your running may be slower than normal.
- Grade 2: More fibres are torn (damage able to be seen on ultrasound or MRI). You’ll feel sudden twinges of pain when walking or trying to lift the affected leg, and you’ll most likely have a limp.
- Grade 3: At least half of the fibres are torn to a complete tear of a muscle or tendon. You’ll likely experience severe pain and weakness. Walking may not be possible and you may need to prescribe crutches while the muscle heals.
Some predisposing risk factors for hamstring strain are: poor timing of muscle contraction and poor running mechanics, fatigue and inappropriate training loads, not warming up, slippery playing surfaces and nerve issues relating to the lower back.
Treatment of Hamstring Strain
The goal of physiotherapy is to restore the patient’s function so they can return to sport with reduced risk of reinjury. Depending on the severity, the timeframe for rehabilitation may be 12 weeks or more.
A conservative treatment protocol may progress through the following 3 phases:
- Phase 1: Protect the muscle to encourage healing, reduce inflammation and pain, low grade exercises to maintain flexibility
- Phase 2: Progressively regain strength and restore normal full range of motion at the hip and knee. Increase core strength and control for better stability at the hip and thus reducing the risk of reinjury
- Phase 3: Progressive increase in loading and speed of sport specific activities in preparation for returning to sport.
Surgical intervention for hamstring strains are very rare. They are only indicated for complete ruptures of muscle or tendon.
Heiderscheit, B. C., Sherry, M. A., Silder, A., Chumanov, E. S., & Thelen, D. G. (2010). Hamstring Strain Injuries: Recommendations for Diagnosis, Rehabilitation and Injury Prevention. The Journal of orthopaedic and sports physical therapy, 40(2), 67-81. doi: 10.2519/jospt.2010.3047
Hellinckx, B., Kothekar, V., Thomas, E., Yona, T., & Lowe, R. (n.d.). Hamstring Strain Retrieved December 05, 2016, from http://www.physio-pedia.com/Hamstring_Strain
WebMD Medical Reference. (2015, June 21, 2015). Hamstring Strain Retrieved December 05, 2015, from http://www.webmd.com/fitness-exercise/hamstring-strain#1
www.sportsinjuryclinic.net (Producer). (2010, December 05, 2016). Assessment of a Suspected Hamstring Strain (tear). [Video] Retrieved from https://www.youtube.com/watch?v=xRXZIfvM–w