Central Cord Syndrome

What is Central cord syndrome?

Central cord syndrome is an incomplete spinal cord injury. It is the most common type of traumatic spinal cord injury, which is characterized by motor function impairment in both arms and to a lesser extent in legs. Depending on the extent of the injury there can also be sensory loss below the level of the injury ^{[1, 2, 3]}. Spinal cord contains large nerve fibers that carry information from cerebral cortex to the spinal cord. After incomplete injury, the brain still can send and receive some information below the site of injury.

Sagittal image of Spinal cord and are of injury in Central cord syndrome.
Image source: aans.org

Pathophysiology and incidence

Hyperextension of the neck
Image source: emedicene.medscape.com

This syndrome is usually due to a neck trauma or in case of herniated intervertebral disc. Traumatic injury causing the central cord syndrome is called hyperextension injury- the head is flung backwards ^[1].

Central cord syndrome is more commonly found in persons over 50 years of age, due to age related weakening of spinal structures – Spondylosis. Spondylosis is weakening of neck vertebrae and discs, and hypertrophy of ligaments. This degenerative disease narrows the spinal canal; therefore it is easier to damage the spinal cord when experiencing such injury ^{[1, 4]}.

This syndrome is more commonly observed in males, than females ^[2].There is a pattern of causes for different age groups. In young persons this syndrome is usually due to trauma, for example, sports injuries or car accidents ^[5]. For older people the injury is usually due to falling ^[1].

Symptoms

Patients usually experience motor weakness in the extremities that is more profound in arms than in legs. Motor weakness can present as complete paralysis or loss of fine control of the movements. There might also be sensory loss below the level of spinal injury.

Some patients experience different sensations in arms or legs: dull or burning pain or tingling sensation. Loss of bladder control can also occur ^{[2, 3]}. There are also a number of other complaints that occur after the initial period of trauma:

• Disturbance of the autonomous homeostasis- autonomic dysreflexia. It is a sudden, uncontrolled hypertension caused by imbalance of sympathetic reflexes. A variety of conditions caused by patient being immobile (urinary tract infection, bowel distention, fractures, lung emboli and many other) can cause an episode of autonomic dysreflexia.
• Neurogenic bladder- loss of normal bladder function, which causes retention of urine.
• Spasticity can be experienced in both upper and lower extremities.
• Neuropathic pain below the level of injury
• Pressure ulcers (bed sores) can occur if the patient has lost sensory function. Patient doesn´t feel the continuous pressure on the skin, which causes the formation of bed sores.
• Neurogenic bowel- loss of normal ability to pass stool ^[1].

Diagnosis

There are steps that have to be taken when evaluating patient with neck injury. First of all it is very important to provide first aid. The person should not be moved without a neck brace, because it can further damage the spinal cord.

The steps taken in hospital settings usually are:

• Complete medical and accident history: how the injury was acquired, previous medical conditions, medications taken by the patient.
• Neurological examination

Neurological examination includes assessment of the functions of central and peripheral nervous system. Doctor will assess all movements and strength of muscles and tendon reflexes, as well as sensation all over the body.

• General examination

  • General examination includes assessment of all organ systems. In case of spinal cord injury it is possible that there is impairment of bladder function. Since central cord syndrome is usually due to a trauma, any damage to other organs and systems has to be excluded.
• X-ray imaging can produce an image of bone structures. It is possible to detect fracture, dislocations, and spondylitic changes. Flexion and extension x-rays can help in evaluating the stability of spinal column. It is necessary in order to assess if spinal column stabilizing surgery is necessary.
• CT imaging will show bony structures more efficiently than plain X-ray. It is possible to assess the spinal canal and structures around it.
• MRI is used to confirm the diagnosis. It will show evidence of spinal cord injury and its cause. With MRI damage to other soft tissue structures can be assessed ^{[1, 2]}.

The combination of clinical examination and imaging studies can give a complete understanding of the severity of spinal injury and help in making a treatment plan.

Treatment

For patients with central cord syndrome there are many treatment options, depending of the severity of the condition. Surgical treatment is used to repair the initial cause, if it is possible. Non surgical treatment focuses on relieving the symptoms and renewing body functions to close to normal level.

Acute surgical treatment is rarely necessary. It is used only when there is a continuous pressure on the spinal cord with worsening of the symptoms. Surgery is best to be performed when the swelling of spinal cord has minimized. Usually the neck vertebrae are stabilized using screws and rods. If there has been herniation of the disk, it can also be completely or partially removed.

Non-surgical treatment involves:

• Immobilizing neck with a collar
• Corticosteroids are used to reduce inflammation and lowed the blood flow to the injury
• Physical therapy in order to recover the motor function.
• Occupational therapy is used to introduce the patient back in everyday life and teach how to cope with disability
• Autonomic dysreflexia can be prevented with proper care of the patient and drugs to reduce the blood pressure.
• Neurogenic bladder is managed by placing a catheter for urine drainage
• Anticonvulsant medication to deal with the neuropathic pain ^[1].

Prognosis

The prognosis of Central cord syndrome is better in case the underlying cause is injury with swelling of the spinal cord. If hematoma or ischemia has occurred, the prognosis of full recovery is not as likely. Young patients after trauma have a higher rate of recovery without surgical intervention. For elder patients surgery is usually necessary. In case of this syndrome, leg and bladder function is first to return, following return of arm function and dexterity ^[1].

References

1. http://emedicine.medscape.com/article/321907-overview
2. http://www.aans.org/Patient%20Information/Conditions%20and%20Treatments/Central%20Cord%20Syndrome.aspx
3. http://www.ninds.nih.gov/disorders/central_cord/central_cord.htm http://emedicine.medscape.com/article/1144952-overview
4. https://radiopaedia.org/articles/central-cord-syndrome