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What Causes A Quadriceps Muscle Injury?

There are two types of injury to muscle. A muscle strain occurs when muscle fibres are pulled apart during a very strenuous activity such as jumping or all-out sprinting. A muscle contusion is caused by a direct blow to the muscle, usually during a contact sport such as football, soccer, or hockey.

Both a strain and a contusion involve the disruption of muscle fibres, although contusions can be worse than strains.

How Are Quadriceps Muscle Injuries Diagnosed?

The severity of an injury to the quadriceps muscles can vary from minor bruising to a complete tear. Injuries are easily hidden by the large size of the thigh muscle so that bleeding and swelling in the deep part of the muscle are often under-estimated.

The severity of the muscle injury is determined by assessing the active range of motion of the knee joint; that is the range of motion that you can perform on your own, unassisted.

Other factors used to grade injury severity include:

  • pain with passive flexion of the knee joint (the examiner stretches the quadriceps muscles)
  • tenderness of the muscle
  • strength loss of the muscle
  • swelling
  • presence of bruising
  • a previous injury to the muscle


Last modified date: February 6, 2017