Tetraplegia: Definition, Causes, and Treatments

Tetraplegia is a paralysis caused by an injury of the cervical spinal cord. This can result in a partial or total sensory and motor loss of the four limbs and torso. The injuries that occur above level C4 often result in respiratory deficiency.

Tetraplegia

Epidemiology /Etiology

In the United States there is an estimated incidence of tetraplegia or paraplegia of 230 000 persons a year.

Eighty percent of the tetraplegic cases are men and almost 60 percent of the cases arise from traffic accidents. Almost 50 percent of the patients were between 18 and 25 years old at the time of the accident. The most often affected levels are C4 - C7. Half of the patients have physiotherapy, with an average of 3 times a week.

Characteristics/Clinical Presentation

Patients with tetraplegia have different clinical presentations, depending on the level of the injury. In general all patients have motor and sensory deficits in arms, trunk and legs.

The spinal cord can be crushed (e.g. due to compressing forces caused by translation of a vertebrae or segment) or torn (e.g. due to extreme tension caused by an extreme movement of the spine causing trauma of multiple tissues).

In case it is torn, it will likely have a better prognosis. When the spinal cord is crushed the decompression is urgent within 2-3 hours, otherwise the prognosis will worsen.

In case of a high tetraplegic lesion (above C3) it is possible that the patient experiences a locked-in-syndrome. This means that he or she is aware of everything, but there is no communication possible or communication is reduced to vertical eye movements and blinking.

The most common complications are:

• Respiratory problems such as atelectasis, hypersecretion, brochospasms, pulmonary edema and pneumonia.
• Pulmonary thromboembolism and other embolisms (blood clots).
• Urinary and pulmonary infections
• Pressure sores
• Spastic muscles
• Loss of bladder and bowel control
• Pain

Differential Diagnosis

There is no differential diagnosis, the ASIA classification excludes other disorders.

We can differentiate between tetraplegia and paraplegia, and between tetraplegia and tetraparesis. We speak of tetraparesis if the paralysis is not complete.

The difference between tetraplegia and paraplegia lies in the affected levels, we say everything above level Th1 is in the category of tetraplegia. Below C8 until the cauda equina is paraplegia.

Diagnostic Procedures

An early and accurate diagnosis of lesions of the spine and cervical spinal cord in tetraplegic patients is important. To find out which part of the spine is damaged they could use imagining studies such as computed tomography (CT) and magnetic resonance imaging.

Sometimes they use CT or MRI scan with contrast for a more accurate diagnosis. In case of diseases of the spinal cord they do a blood test and/or spinal tap to investigated the blood and/or spinal fluid.

Examination

The initial assessment of individuals with acute spinal cord injury should include a complete history, physical, and neurologic examination to determine the level of injury as accurately as possible.

Physical assessment should include an evaluation of breathing pattern and effectiveness of cough. The most common abnormal breathing pattern is an isolated diaphragmatic breathing with chest wall retraction during inspiration.

The neurologic examination, more specific the motor and sensory examinations, of tetraplegia includes:

The International Standards for Neurological Classification of Spinal Cord Injury (ISCSCI)

Electrophysiological measures: stimulated muscle testing, strength-duration (SD) testing, evoked-potential testing, nerve conduction velocity (NCV) testing, and needle and dynamic electromyography (EMG) testing

These motor and sensory examinations could be used for the assessment of muscles strength and sensation.

For the assessment of upper limb in tetraplegia the Sollerman hand function test, Capabilities of the Upper Extremity instrument (CUE), the Motor Capacity Scale and the Tetraplegia Hand Activity Questionnaire are useful instruments. At least one or a battery of several of these tools should be used for the assessment of the hand function and to collect evidence for interventions.

In the systematic review, Julio C. Furlan et al., they collect eight different outcome measures that were used to assess disability in the spinal cord injury population:

• Functional Independence Measure (FIM)
• Spinal Cord Injury Measure
• Walking Index for Spinal Cord Injury (WISCI)
• Quadriplegia Index of Function (QIF)
• Modified Barthel Index (MBI)
• Timed Up & Go (TUG)
• 6-min walk test (6MWT)
• 10-m walk test (10MWT)

Tetraplegia

Medical Management

The medical management of tetraplegia could be the treatment of the cause, an invasive technique might be used to release pressure or attempts can be made to repair damage. Most of these techniques are still in an experimental stage (eg. use of stem cells.

More often the treatment is aimed on the functional recovery. The ability to use the upper limb(s) has an important influence on the independency of the patient (use of a wheelchair, pressure relief manoeuvres, independent transfers, etc.

Therefore procedures such as: the transfer of the teres minor motor branch for triceps reinnervation and biceps-to-triceps transfer for elbow extension could give the patient an improvement in function.

Most physicians believe these procedures are beneficial but unfortunately they are not often used since the risk/benefit ratio is still unknown. The known literature consist of small case reports.

Patients that lost their ability to breathe autonomously are ventilated through a tracheotomy and are more likely to get a respiratory infection and/or decease. A better technique is the use of a diaphragm pacing system which electrically stimulates the phrenic nerve to pace the diaphragm. This technique has promising results but more trials are necessary to evaluate the impact on the patients.

Physical Therapy Management

As mentioned above, the ability to use the upper limbs is considered crucial to regain independence. A review of several studies showed that different training techniques may improve arm and hand functioning after cervical spinal cord injury, with tetraplegia as a consequence.

There is some evidence that suggests that task-specific training (with functional electrical stimulation if the grasp function is to weak) is ideal to improve the hand function. Almost all studies showed an improvement in arm and hand function and/or activity level.

Therefore a physical therapist should set individual goals for each patient and use a specific (suitable) training program to gain success.

If the surgeon and physician decide to use a procedure as mentioned above, the physiotherapist’s task will be to reinforce the muscle and learn the patient to control his muscle individually.

Furthermore the lack of physical activity which is often paired with chronic spinal cord injury should be one of the key points a physical therapist should address. Innovative techniques such as :the use of functional electrical stimulation lower extremities cycling[, treadmill gait and electrical stimulation during gait are used to regain/maintain muscle mass in the legs , strengthen the bones and to gain many other benefits from physical activity (cardiovascular).

Hypotension and orthostatic hypotension is often seen is these patients, a patient should be instructed to get up (form a lying or seated position) gradually and slowly.

Circulatory exercises before standing up might be helpful to stimulate the blood flow. Furthermore medication, a special diet (with enough water and salt) and regular exercise therapy should be given to prevent hypotension.

For the respiratory problems that can come with tetraplegia secretion removal techniques, use of expiratory flow devices are recommended and the improvement of various components of cough (Vital capacity, flow rate, maximum respiratory pressures) are recommended. Intermittent positive pressure breathing (IPPB) can be used as a treatment for or to prevent atelectasis.

Studies have shown that inspiratory muscle training with a threshold trainer at low loads increases the strength of the respiratory muscles in quadriplegic patients. The efficacy for quadriplegics has not been proven but it is suggested that this will help the respiration as it does for COPD patients.