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Dr Tom Cross

Injury to an athlete may be considered to be either;

1. An ACUTE injury: Injury occurs suddenly to usually previously normal tissue. The principle is the force exerted at that immediate point in time on the tissue (ie. muscle, tendon, ligament, and bone) exceeds the strength of that tissue damaging it. Forces commonly involved in acute injury are muscle contraction (eg. muscle/tendon tears) twisting injury to joints (ankle sprains, knee ligament injury) and direct trauma (impact from an object or opponent).

2. An OVERUSE injury: Any repetitive activity can lead to an overuse injury. The principle in overuse injury is that repetitive microtrauma overloads the capacity of the tissue to repair itself. The most common overuse injuries are inflammation of tendons (Tendinitis) and Stress Fractures of bones.

Common Overuse Injuries

  • Patellar Tendinitis
  • Achilles Tendinitis
  • Rotator Cuff (Shoulder) Tendinitis
  • Tenoperiostitis of Tibia (ie. Shin splints)
  • Stress Fracture of Tarsal (foot) bones
  • Pars Interarticularis in Lumbar Spine

To better understand overuse injury it helps to think in terms of what is happening at the microscopic level to the tissue that has been stressed during the repetitive workouts. During exercise the tissues (muscles, tendons, bones, ligaments, etc) experience excessive physiological stress. When the activity is finished the tissues undergo adaptation so as to be able to withstand a similar stress in the future if required. Overuse injury occurs when the adaptive capability of the tissue is exceeded and tissue injury then develops. That is, there is not enough time for adaptation to occur before the next work out.

The adaptive capability of the tissue may be exceeded secondary to excessive repetitive forces attributable to one or a combination of the following factors:

Intrinsic Factors

Extrinsic Factors

Poor Biomechanics

Training Errors - excessive volume

Lack of Flexibility

Training Errors - excessive frequency

Muscle Imbalance

Training Errors - excessive intensity

Muscle Weakness

Training Errors - faulty technique

Sex (women > men)

Surfaces (concrete vs grass)


Shoes (inappropriate or worn out)


Body Composition

The cause of overuse injury is very often MULTIFACTORIAL and can involve both extrinsic and intrinsic factors.

The greatest challenge is to identify and correct the cause(s) of injury. It is not sufficient to just diagnose and treat the injury. The cause(s) of the injury must be identified and treated otherwise the athlete may suffer a recurrence of the same or similar injury.

For many injury categories the injury can be thought of as sport specific or sport generic. The physical demands of some sports create high frequencies of specific injuries that would not present across all sports (eg Osteitis Pubis/Adductor Tendinitis in AFL). It is overuse injuries, rather than acute injuries, that tend to be sport specific.

In general, the treatment of overuse injuries involves relative rest, that is, the avoidance of aggravating activities while maintaining fitness (cross-training); the use of ice and various electrotherapeutic modalities (ultrasound, interferential); soft tissue massage and drugs, such as NSAIDS (topical or oral route).




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