Hamstring injuries are something we know about all too well at Arsenal.

Hamstrings are the tendons which attach the hamstring muscles of the thigh to the thigh bone and are the cause of one of the most common injuries in football. The purpose of hamstrings is to bend the knee as well as straighten or extend the hip and the hamstring muscles one of the most important muscles in the body when it comes to running and jumping.

The majority of hamstring injuries heal without the need for surgery and the general goal of treatment is to ensure that they heal without any scaring being caused. Treatment generally consists of rest, compression, ice.

Here are the grades of hamstring injury and how long players can expect to be sidelined for in the event of ‘doing a hammy.’

Hamstring grades:

1 Tightness and awareness of some hamstring discomfort but no difficulty walking. A grade 1 tear will impact your ability to run at full speed and could produce some swelling of the muscle. It will also be tender when palpated. This type of injury can usually be recovered from in a matter of days.

2 This will produce a limp and sudden twinges of pain during ‘activity’ will occur. Like a grade 1, the muscle will be swollen and tender when palpated but it is also likely to produce pain when the knee is bent. This is the type of hamstring injury most fans think of when they hear of the injury and generally results in a 2-4 week layoff.

3 Moving into ‘severe’ territory, a grade 3 hamstring tear means that half or all of the muscle has been torn. Needing crutches to move around, a player will be sidelined for months rather than weeks with a grade 3. Swelling is immediate and bruising appears within 24 hours.