The hamstring comprises three muscles: the biceps femoris (long and short head), semitendinosus and semimembranosus. Hamstring injuries are common among recreation and competitive athletes and can occur from repetitive microtears or during a single event overexceeding the muscles’ capacity and length.
The management for hamstring injuries can be short or long-term depending on the severity and type of injury. It will also depend on which hamstring muscle has been injured. The following grades will be applied to a hamstring injury, guiding treatment:
- Grade 1: minor strain, minimal tearing and some discomfort but no significant loss of function.
- Grade 2: partial tear, more pain and loss of function with some bruising and swelling.
- Grade 3: complete tear or rupture, severe pain, significant loss of function, bruising and possibly a palpable gap in the muscle.
Frequently Asked Questions
What are the different types of hamstring injuries?
A hamstring injury can be categorised as a strain or tear to the tendons or large muscles of the posterior of the thigh and most hamstring injuries are accepted as multifactorial and complex. Hamstring injuries have been described as having a sprinting-type or stretching-type mechanism, with the latter taking longer to heal. The literature states that nearly 1 out of 3 hamstring injuries will recur within weeks of an athlete’s return to sport. At Sydney Muscle & Joint Clinic our physiotherapists use high load isometrics and eccentric exercises to help increase capacity and resilience.
What causes hamstring injuries?
High-speed running type of injury is the most common mechanism for a hamstring injury and commonly affects the bicep femoris muscle. This type of hamstring injury typically carries a shorter recovery time than the stretch-type of hamstring injury.
The stretch-type of hamstring injury generally accounts for approximately 19% of incidences and commonly affects the semimembranosus muscle. These injuries normally occur from movements in sports like kicking or lunging.
How do you diagnose or assess a hamstring injury?
Your physiotherapist may begin with taking a history of the patient and information regarding the injury including how the injury occurred, symptoms, the onset and duration of symptoms and your current functional limitations. Diagnosing a hamstring injury will often take a symptomatic approach where your physiotherapist will look for a patient reporting a sudden onset of pain in the back of their thigh, reproduction of this pain when the hamstrings are stretched passively and/ or activated, pain on palpation over the muscle and if there is a loss of function, such as an antalgic gait or limping.
In addition to this, your physiotherapist may test passive and active range of motion of the hip and knee joint, strength of the hamstrings and perform special tests such as a straight leg raise, hamstring flexibility test or palpation of the ischial tuberosity.
Imaging of the injured hamstring may be necessary and can determine the severity of the injury. An MRI or ultrasound can show us tears or bleeds, though it is not needed to begin physiotherapy.
What are best current treatment recommendations for hamstring injury?
The prognosis and treatment of hamstring injuries may differ slightly depending on the type of injury, the mechanism of injury, the severity and the patient, however they will generally follow a similar protocol and sequence of treatment.
In the early stages, physiotherapists should have a focus on protecting the injured tissue by means of minimising atrophy of the muscle through isometric exercises and minimising pain in the injured tissue. There should also be an emphasis on preventing excessive scar tissue development through promotion of neuromuscular control, or gentle isometric contractions, within a protected range of motion to enhance the initial healing stage without further injury to the tissue.
Following this, a progressive overload strength program will be implemented to increase muscle hypertrophy and strength. This will begin as eccentric exercises to promote tendon healing and rebuild muscular strength. As you continue your rehabilitation, concentric exercises can be incorporated to work towards a return to sport or normal activities.
The final stage of rehabilitation will focus on a gradual return to activity. This may include sport-specific exercises, increasing in intensity and complexity such as sprinting, agility drills and jumping and other plyometric exercises.
At Sydney Muscle & Joint Clinic, we follow the Aspetar Hamstring Protocol. This protocol focuses on six stages of rehabilitation with a strong focus on promotion of healing, regaining full muscle function and neuromuscular control and integration into full sports specific participation.
- Stage 1: protect scar tissue development, minimise muscle atrophy and minimise pain.
- Stage 2-3: regain full voluntary neuromuscular control over the injured muscle, regain pain-free hamstring strength, develop neuromuscular control of trunk and pelvis with progressive movement speed and pain free running up to a maximal speed with changing directions.
- Stage 4-6: symptom-free during all activities and complete three progressive sports-specific sessions with no pain.