Paraplegia and Paraplegic

Paraplegia Information Sections

• Causes of Paraplegia
• Symptoms of Paraplegia
• Function of Spinal Nerves Affected by Paraplegia
• Secondary Medical Complications in Paraplegics
• ASIA Impairment Scale

Causes of Paraplegia

Note: The cervical spinal nerves exit the vertebrae above the cervical vertebrae, except for C7, where the C8 spinal nerve exits below the C7 vertebrae. All spinal nerves then exit below the thoracic, lumbar and sacral vertebrae.

Paraplegia due to a spinal cord injury results in an impairment in motor or sensory function of the lower half of a person's body. The condition occurs due to damage to the cellular structure of the spinal cord within the spinal canal. The area of the spinal cord which is affected in paraplegia is either the thoracic, lumbar, or sacral regions of the spinal column. If the arms are also affected by paralysis, quadriplegia/tetraplegia is the correct terminology.

Symptoms of Paraplegia

Injury to the spinal cord at the thoracic level and below result in paraplegia, with the arms and hands not affected. People with injuries to the spinal cord segments T-1 to T-8 usually retain control of the arms and hands but have poor trunk control and balance due to the lack of abdominal muscle control. Lower thoracic injuries (T-9 to T-12) retain good truck control and good abdominal muscle control. The sitting balance of people with lower spinal cord injuries is usually very good. Lumbar and Sacral injuries result in decreased control of the hip flexors and legs.

Spinal Nerves and Levels

Each part of the body is supplied by a particular level or segment of the spinal cord and its corresponding spinal nerve. Function below the level of spinal cord injury will be either lost or impaired

This is approximately the same for every person:

Function of the spinal nerves in the cervical section of the spinal cord are usually unaffected by paraplegia and remain fully functional in a paraplegic individual.

C3,4 and 5 Supply the diaphragm (mostly C4) (the large muscle between the chest and the belly that we use to breath).

C5 also supplies the shoulder muscles (deltoid) and the muscle that we use to bend our elbow (bicep).

C6 Bends the wrist back (extension), and externally rotates the arm (supinates).

C7 Straightens the elbow and wrist (triceps and wrist extensors); pronates wrist.

C8 Bends the fingers (flexion).

Function of the spinal nerves below the cervical sections of the spinal cord are usually impaired due to damage in either the thoracic, lumbar or sacral areas, resulting in paraplegia.

T1 Spreads the fingers and supplies small muscles of the hand.

T1 –T12 supplies the chest wall (intercostal muscles) and abdominal muscles.

T10 - L2 Psychogenic erections (thought controlled).

L2 Bends the hip.

L1, L2, L3, L4 Thigh flexion.

L2, L3, L4 Extension of leg at the knee (quadriceps femoris)

L2, L3, L4 Thigh adduction.

L4, L5, S1 Thigh abduction.

L4, L5, S1 Dorsiflexion of foot (tibialis anterior).

L4, L5, S1 Extension of toes.

L4, L5, S1, S2 Flexion of leg at the knee (hamstrings).

L5, S1, S2 Extension of leg at the hip (gluteus maximus).

L5, S1, S2 Plantar flexion of foot.

L5, S1, S2 Flexion of toes.

S2, S3, S4 Control a man's ability to have a reflex erection.

S2, S3, S4 Ejaculation is generated by the bulbospongiosus muscle under the control of a spinal reflex via the pudendal nerve.

S3,4 and 5 supply the bladder, bowel and sex organs and the anal and other pelvic muscles.

Secondary Medical Complications

As a result of the decreased loss of feeling or function in the lower extremities, paraplegics can be susceptible to a number of secondary medical complications. These include pressure sores (decubitus), thrombosis, low blood pressure, autonomic dysreflexia and pneumonia. Dysfunction of the bowel and bladder will usually also occur. Sexual functioning is frequently impaired or lost with SCI. Men may have their fertility affected, while a women's fertility is generally not affected. Physiotherapy and various assistive technology, such as a standing frame, as well as vigilant self observation and care may aid in helping to prevent future and mitigate existing complications.

As paraplegia is most often the result of a traumatic injury to the spinal cord tissue and the resulting inflammation, other nerve related complications can and do occur. Cases of chronic nerve pain in the areas surrounding the point of injury are not uncommon. There is speculation that the "phantom pains" experienced by individuals suffering from paralysis could be a direct result of these collateral nerve injuries misinterpreted by the brain.

ASIA impairment scale

Spinal cord injuries are classified by the American Spinal Injury Association (ASIA) classification. The ASIA scale grades patients based on their functional impairment as a result of the injury, grading a patient from A to D