Concussion Intro

Concussion = mTBI

Very common→ ~3 million cases/yr in US

resolves in how long?

Adults: 14 days

<18 yrs: 3-4 wks

10-33% who will have prolonged or incomplete concussion recovery for how long?

Termed as either:

Postconcussion Syndrome (PCS) & Persistent Postconcussion Symptoms (PPCS)

Adults: >14 days

<18 yrs: 30 days

who exp concussion most commonly?

0-4 y/o

Males 15-24 y/o

Females >65 y/o

why/how do concussions most commonly occur?

Falls are most common (trauma)

Sports→ concussion is most commonly reported sports injury

Females > Males

When a pt exp concussion,

1st. Mechanical deformation of neurons→ failure of energy-dependent ion transport pumps

K+ out/Ca2+Na+ in→ water follows Ca2+/Na+→ edema

Neuron tries to restore ionic homeostasis→ uses LOTS of energy→ energy crisis

When a pt exp a concussion,

2nd. Mechanical deformation of neurons→ releases excess glutamate into extracellular space

Creates MORE Ca2+ influx, MORE glutamate in extracellular space (Ca does not want to be around glutamate)

Neurometabolic cascade of events leads to functional cell injury. Functional cell injury leads to energy crisis at level of cell.

Little to no cell death occurs in concussion. Functional disturbance of nervous system. disturbances in neurotransmitters & microstructural changes.

3. Initial decrease in cerebral blood flow→ lack of cellular nutrition makes

cells vulnerable to injury

Microstructural change from concussion such as Axonal stretch can have what affects?

Impaired synaptic transmission

Transient (recovery) vs permanent damage

Microstructural change from concussion such as inflammation can have what affects?

Functional disruption of neural activity