SPINAL INJURIES

 ANATOMY

The spine in man is a vertical column of 33 vertebrae piled one on another. The vertebrae vary somewhat in form from one part of the spine to another. To the front is the body - a cylinder of bone, which is the strong, weight-bearing part of the vertebrae. Behind the body is a ring of bone surrounding and protecting the spinal cord. The spinal cord is a downward extension of the brain. it runs through the spine and gives off branches to supply all parts of the body. From the ring of bone at the back of the vertabrae arise three knobs of bone - a transverse process to each side and a dorsal spinous process running backwards. These knobs serve only for the attachment of muscles. Between the bodies of the vertabrae lie the discs - a rubbery bag filled with a gelatinous material. These act as shock absorbers and also allow movement. When the spine bends forwards, the posterior part of the disc becomes stretched. If a heavy weight is being lifted at the same time, the resulting compression of the disc can cause a tear in its posterior part, allowing some of the contents to be squeezed out to press on the nerves leaving the spinal cord at that level. This is known as a slipped disc. If the resulting pain is felt in the back, it is termed lumbago and if the pain is felt down the course of the nerve in the leg, it is called sciatica.

INJURIES

1. Fractured processes Fractures of the processes are painful but minor injuries which are comparable to bruising of the surrounding muscles.

2. Wedge compression fractures When a force transmitted along the spine is greater than that which can be absorbed by the shock absorbers, the body of one or more vertebrae becomes crushed. This is greatest at the weakest point - the front, making the vertebrae wedge-shaped when viewed from the side. Such injuries are caused by a fall from a height onto the feet or ejection from an aircraft. This is not a serious injury but causes pain for a few weeks.

3. Fracture-dislocations Are caused by a combination of compression, forward rotation and flexion of the spine. There is a fracture of one vertebrae and displacement between it and the next. The resulting misalignment of the bony rings at the back of the vertebrae can cause damage to the spinal cord with temporary or permanent loss of power and sensation in all parts of the body below that level. These fractures must be handled very carefully to prevent damage to the cord where there is none already and to ensure that any temporary damage doesn’t become permanent.

EXAMINATION

When a patient refers to his "back" he may not mean his spine but back as opposed to front and he may be indicating the back of his chest or pelvis. The patient with a suspected spinal injury should therefore be asked to say whether his pain is in the midline or to one side. He may be able to point to the corresponding spot on the First Aider’s back.

Signs of injury to the spine

1. Abrasions or imprint of clothing.

2. Swelling obscuring the bony prominence of one or more dorsal spines.

3. Abnormal prominence of one spine where displacement at a fracture has caused a step in the spine.

4. A sideways step in the line of bony prominences (rotational displacement).

5. Tenderness.

6. Loss of power or sensation below the level of injury.

The first Aider cannot tell the difference between the different fractures and should treat as serious fractures all cases of pain in the midline and unconscious patient who exhibits others of the above signs.

TREATMENT

Strong analgesics can be administered but the patient should be warned of the risk of vomiting. The movement of a spinal injury is so critical that there should be no haste and the best qualified aid should be obtained before any movement is undertaken. Forward flexion and rotation should be avoided and it is best to load the patient to lie on his abdomen.

THE NECK

The neck vertebrae have no transverse processes. The body of C1 is missing having been attached as a peg to the top of the body of C2. The skull rocks on C1 to give nodding movements of the head. Turning movements take place as C1 swivels around the odontoid peg of C2. In judicial hanging, the head is forced forwards until the peg crushes the spinal cord. Fractures are commoner in the neck than in any other part of the spine - largely due to its being less well protected. They are also more serious.

Fractures

There are no fractured transverse processes and wedge-compression fracture are not common. The higher the level of a fracture dislocation, the more serious any resulting paralysis. The highest fractures cut off the nerve supply to the muscles of respiration - resulting in death from asphyxia.

Treatment

Handling must be as careful as for other spinal injuries. Strong analgesic cannot be given as the risk of vomiting is unacceptable.

A cut throat can cause the patient the bleed to death from severed carotid arteries - one on either side of the windpipe. To treat such an injury, the First Aider places himself behind the patient and applies firm and sustained pressure to a dressing over the wound, whilst pushing the head forward. Foreign objects should not be removed from wounds in this area lest similar torrential bleeding is released.

 30/12/01