IB Sports, exercise and health science B.3.1.2 Differences Between Acute Trauma and Cumulative Trauma Injuries Notes

Acute trauma

1. Acute trauma results from a single identifiable event that delivers enough force to damage tissue right away.
2. The athlete usually knows the exact moment the injury occurred.

Mechanisms of acute trauma

1. Direct impact occurs when one body or object strikes another, such as a tackle or collision.
2. Sudden force comes from a single high-load action such as landing badly from a jump.
3. Unexpected direction changes twist a joint while the foot is planted, such as a sharp change of direction with the studs gripping the turf.

Signs of acute trauma

1. Sharp pain appears at the moment of injury.
2. Rapid swelling develops in the minutes that follow.
3. Bruising appears as blood collects in the surrounding tissue.
4. Loss of function prevents normal movement of the injured part.

Cumulative trauma

1. Cumulative trauma, also called overuse injury, develops from repeated loading over weeks or months.
2. Each loading event is too small to cause damage by itself, but accumulated microtrauma outpaces the body's ability to repair.

Patterns of loading

1. Repeated movements load the same joints in the same way, such as a baseball pitch or a swimmer's stroke.
2. Ongoing impact stress loads bones and joints with smaller but frequent forces, as in distance running.
3. Regular microtrauma that fails to heal between sessions accumulates faster than the body can repair it.

Signs of cumulative trauma

1. Gradual onset of pain or stiffness develops over weeks.
2. No single injury moment can be identified.
3. Symptoms worsen with continued activity and improve with rest.
4. Treatment is often delayed because the athlete pushes through early warning signs.

Tissue responses to trauma

1. Different tissue types respond differently to the same force, which is why two athletes hit by the same impact can have very different injuries.

Connective tissue (ligaments and tendons)

1. Ligaments connect bone to bone; stretch injuries are called sprains.
2. Tendons connect muscle to bone; stretch injuries are called strains.
3. Healing is slow because connective tissue has a poor blood supply.

Muscle

1. Muscle can be injured by tears, strains, or contusions (the bruising from a direct blow).
2. Muscle has a rich blood supply, so healing is usually faster than for connective tissue.
3. Scar tissue often replaces original muscle fibres during repair, and scar tissue is stiffer and weaker.

Bone

1. A single large force causes an acute fracture.
2. Repeated smaller forces cause a stress fracture, a small crack that grows when remodelling cannot keep pace.
3. Healing depends on adequate blood supply, nutrition, and load management during recovery.

Skin

1. Abrasions are scrapes from sliding contact.
2. Lacerations are cuts.
3. Contusions are bruises.
4. Healing time depends on the depth of the wound and whether infection sets in.

Concussion (functional brain injury)

1. A concussion is a mild traumatic brain injury caused by a force that makes the brain move rapidly inside the skull.
2. The brain itself is not visibly damaged on a standard scan, but function is temporarily disrupted.

Force mechanisms

1. Direct hits to the head, such as a punch or head-to-head collision, drive one obvious mechanism.
2. Indirect forces, such as a heavy body tackle that snaps the head forward and back, shake the brain without touching the skull.
3. Rotational forces spin the head sharply and may be the most damaging because they stretch and shear neural connections.

Signs of concussion

1. Confusion or disorientation at or after the moment of injury.
2. Memory problems around the event.
3. Balance issues when standing or walking.
4. Blurred vision or light sensitivity.
5. Headache, nausea, and slowed reaction time can also follow.

Assessing acute or cumulative trauma

1. Was there a specific incident that caused immediate pain? Suggests acute trauma.
2. Has there been repetitive stress over weeks or months? Suggests cumulative trauma.
3. Which tissue type is involved, and does its healing speed match the pattern of symptoms?
4. Are there signs of brain involvement such as confusion, memory loss, or balance issues?