Understanding Head Injuries

Head Injuries

• Head injuries are frequently the target of choice in assaults.
• When victims are pushed or knocked to the ground, they often strike their heads.
• The brain and its coverings are vulnerable to blunt trauma, which can be lethal if applied to other areas.
• Head injuries are best understood by categorizing them in three sections:
  • Scalp injuries
  • Skull injuries
  • Brain injuries

Scalp Injuries

• The scalp is the outermost layer of the head, composed of five layers from the outside in.
  • Skin
  • Connective tissue (epicranial aponeurosis)
  • Loose areolar tissue
  • Pericranium

Skull Injuries

• The skull is a diploic bone, with a thicker and stronger outer table compared to the thinner and weaker inner table

• The space in between, gives the skull elasticity. 

• There are two types:

  • Cancellous (trabecular or spongy)
  • Compact (cortical) bone

• Types of skull fractures include:

  • Fissured fracture(linear): A fracture involving only the outer or inner table, or both.
  • Stellate fracture: A radiating fracture with fragmented parts remaining intact.
  • Mosaic fracture (spider's web fracture): A comminuted and depressed fracture, with tissues spreading outwards to form a web pattern.
  • Depressed fracture: The fractured bone fragments are pushed inwards, and the shape mirrors the weapon that caused the trauma.
  • Elevated fracture: One end of the fractured fragment is raised above the skull surface, while the other end is depressed into the cranial cavity, potentially damaging the dura mater.
  • Diastrophic fracture: A fracture that occurs along the suture lines of the skull, common in children and young people.
  • Gutter fracture: The thickness of the skull bones is affected, resulting in irregular depressed fractures of the inner table.
  • Comminuted fracture: The bone is broken into multiple pieces.

• Base of skull fractures: characterized by blood and cerebrospinal fluid (CSF) leakage from the nose, ears, or the back of the neck; associated with anterior, middle, or posterior cranial fossa fractures.

• Ring fracture: A fracture encircling the foramen magnum, usually from a fall landing on the crown of the head.

• Hinge fracture: A fracture that runs across the floor of the middle cranial fossa and through the pituitary fossa (more common in motorcyclists).

Brain Injuries & Intracranial Haemorrhage

• Cerebral concussion: A temporary disruption of neuronal activity without demonstrable brain lesions.

• Clinically, a concussion presents as:

  • loss of consciousness
  • flaccidity of muscles, and,
  • recovery of consciousness, with the possibility of re-losing consciousness.

• Post-concussion syndrome: Neurological symptoms following concussion include headache, dizziness, nervousness, and, in some cases, epilepsy.

• Lucid interval: A recovery period between unconsciousness episodes, when the patient appears perfectly normal.

• Extra-dural haemorrhage (EDH): Bleeding outside the dura mater, often due to a fractured temporal bone and middle meningeal artery rupture. 

• Collected blood leads to intracranial pressure (ICP) increases and brain displacement, resulting in loss of consciousness and coma.

• Subdural haemorrhage(SDH): Bleeding in the subdural space (no mesothelial lining). This results in blood cysts and is commonly seen in children and the elderly.

• Causes of SDH:

  • Glidng movements between the dura and arachnoid mater
  • Bruising and laceration of the brain
  • Minor trauma.

• Subarachnoid haemorrhage(SAH): bleeding in the subarachnoid space, caused by trauma, and certain medical conditions

  • Causes include:
    • All traumatic causes
    • Prolonged hyperextension of the neck
    • Diseases (like atherosclerosis, hypertension, or leukemia)
    • Berry aneurysms of the basilar artery

• Findings in serious brain injuries include:

  • Ipsilateral dilated pupils
  • Contralateral paresis (weakness on the opposite side of the brain from the injury)
  • Lucid interval
  • Automatic movements
  • Possible confusion mistaken for intoxication, leading to arrest.

Spinal Cord Injuries

• Four types of spinal injuries:
  • Concussion: (Whiplash) hyperextension followed by hyper flexion, causing dislocation at C4-C6 with haemorrhage in spinal cord substance, resulting in quadriplegia.
  • Compression: Spinal cord compression in fracture-dislocation (in Pott's disease).
  • Pithing: Killing by stabbing a fine needle into the nape of the neck between the base of the skull and the first cervical vertebrae.
  • Lacerations : Twisting of the neck may produce lacerations without external injuries (like infanticide or wrestling)

This quiz delves into the categorization and details of head injuries, including scalp, skull, and brain injuries. It explores the anatomy of the head and the implications of different types of traumas. Get ready to test your knowledge on this critical topic in medical science!