Hamstring Injuries
The hamstring muscle complex is located at the back of the thigh and consists of 3 muscles.
The Biceps femoris is located on the outside. Semitendinosus and Semimembranosus are located on the inside.
The most commonly inured is the biceps femoris, which accounts for roughly 80% of all hamstring injuries.
The chance of injury increases with:
- Age
- Past history of injury
- Aboriginality
The muscles are most susceptible under fatigue and so general aerobic fitness specific to your sport is important in prevention.
There are other risk factors that are thought to be of significance, including past history of knee, ankle and calf injury, low back pain and ratio of hamstring to quads strength and tightness of the muscles.
A differential diagnosis is important before commencing a treatment and rehab program, including ruling out if pain is from the lower back or gluteal muscles.
The most common story of a patient presenting with a hamstring injury is a sharp pain whilst running fast or sprinting during football sports or athletics. The injuries are placed into 3 grades:
- Grade I – mild strain of a small percentage of fibres
- Grade II – moderate tearing of the muscles, usually in a longitudinal direction
- Grade III – full rupture of the fibres.
There are rare instances where the hamstring tendon ruptures from it’s bony origin or insertion where there is complete weakness. A surgical consultation would be recommended but interestingly not all of these require surgery.
Physiotherapy management
One third of these injuries recur within 1 year, often more severe, therefore use of a specific and adequate training program/rehabilitation is essential. For Grade I-II injuries a healing time of up to 4-6 weeks is generally recommended.
Eccentric strengthening (this is where the muscle is strengthened in a stretched position) decreases risk of recurrence. However, progressive running and agility training and trunk stabilisation exercises were proven to be more effective. Control of lumbo-pelvic region is also very important, so good core activation, running technique and muscle endurance is important.