Tetraplegia

Forms of tetraplegia

A distinction is made between a complete or incomplete paralysis, depending on whether all nerve fibres of the spinal cord are affected or only some of them. Incomplete paralysis has sub-types depending on the location of the lesion. Damage may occur in the anterior section (anterior spinal cord syndrome), in the posterior section (posterior spinal cord syndrome), in the centre (central cord syndrome), in the bone marrow, or on one side (Brown-Séquard syndrome).

The level of injury, in turn, results in different types of damage. An injury to the upper segments results in quadriplegia/tetraparesis, which causes paralyses in the arms and legs. Lower damage causes paraplegia/paraparesis, i.e. paralysis of the legs. An injury to the lumbar part of the spinal cord (from Th12/L1) may cause the conus medullaris syndrome, which affects mainly the bladder, bowel, and sexual functions. An injury to the lower end of the spinal cord (cauda equina) causes paralysis of the legs, in addition to bladder, bowel, and sexual dysfunctions.

The American Spinal Injury Association (ASIA) Impairment Scale is used to classify acquired tetraplegia. The extent of paralysis determines the following categories (American Spinal Injury Association 1992):

• ASIA A - complete: No motor or sensory function is preserved in the sacral segments S4-S5.
• ASIA B - incomplete: Sensory (sensation), but not motor (movement) function, is preserved below the level of injury and includes S4/S5
• ASIA C - incomplete: Motor function (movement) is preserved below the level of injury, and most muscles are either unable to move, or can move only slightly against the force of gravity.
• ASIA D - incomplete: Motor function (movement) is preserved below the level of injury, and most muscles are able to move against the force of gravity, or even against resistance.
• ASIA E - normal: Normal functions (sensory and motor)
  

Symptoms of tetraplegia

Depending on the type of tetraplegia (complete or incomplete), movement and/or sensation is impaired. The control of internal organs may be impaired in the event of lesions above the 5th thoracic vertebra due to the separation of the sympathetic nervous system. In general, the higher the paralysis, the more body parts are affected.

Progression of tetraplegia

Limited motor skills/acute consequences

In the immediate aftermath of the trauma, all muscle functions below the injury location are lost, and reflexes are absent (spinal shock). There is also tachycardia (fast heartbeat), while the pulse can be easily felt and the hands are well supplied with blood (differential diagnosis to distinguish from classic shock). This pseudo-flaccid paresis persists for a few days to weeks before spasticity (excessive muscle tension) develops due to a reorganisation process.

Long-term damage and life expectancy

Depending on the nature and severity of tetraplegia, there may be different symptoms and consequences. Common problems with long-standing, pronounced symptoms are pressure ulcers (pressure sores), and contractures (painfully rigid joints) caused by spasticity (excessive muscle tension).

Whether or not life expectancy is impaired also depends heavily on the severity and, above all, on the location of the plegia. The life expectancy of paraplegics and quadriplegics is only slightly reduced (Niethard & Pfeil 2005). If several concomitant symptoms occur, e.g. if ventilation is necessary, the life expectancy may be more reduced.

Healing time/chances of recovery

The chances of recovery vary depending on the cause. If, for example, an incomplete paralysis is caused by a herniated disc, eliminating the cause (removing the intervertebral disc) may ease the pressure on the spinal cord and make the symptoms disappear. Residual symptoms may remain if the spinal cord has already been damaged by the pressure on the intervertebral disc.

If the cause cannot be eliminated, and the injury is thus permanent, there is currently no chance of a recovery. However, consistent rehabilitation assists in restoring functions, learning compensation strategies, and improving the patient’s quality of life.

Other complications or consequences

If the bladder function is impaired, especially if the bladder cannot be completely emptied, urinary tract infections are more likely. A catheter may be necessary if the patient is no longer able to independently empty his or her bladder.

Diagnosis: tetraplegia

Imaging techniques such as CT, MRI, or X-ray are used to diagnose possible tetraplegia.

First and foremost, the diagnostic process must establish the cause of the tetraplegia. Initial hypotheses can be made based on the case history and a clinical neurological examination. Various examinations may be useful, depending on the suspected cause:

• X-ray, computed tomography (CT) to display the osseous structures, especially if an accident is suspected to be the cause
• Magnetic resonance imaging (MRI) for a more accurate assessment of the spinal cord
• Lumbar puncture to examine the cerebrospinal fluid
• Neurophysiological studies (evoked potentials - EVP) to assess nerve conductivity
• Examination of the blood supply and blood vessels, especially in traumatic injuries to the neck
• Blood tests

Treatment of tetraplegia

Acute tetraplegia, which is usually caused by an accident, must be treated immediately. Emergency services use an ambulance or a helicopter to transfer the patient to the trauma room in the nearest specialist hospital. The following occurs in the hospital:

• the diagnosis
• acute treatment of complications (intestinal obstruction, cardiovascular failure, etc.)
• surgery if necessary (in the case of bone fractures: immobilisation/plating)
• intensive care monitoring and follow-up

Surgery is also indicated if the tetraplegia is caused by a tumour or other mass (e.g. herniated disc). Routine treatment also includes special medication for inflammatory causes, tumours, coagulation disorders, or severe post-traumatic pain.

Symptomatic treatment of sexual, bladder, or sensory disorders (dysaesthesias) may be required at a later stage. Spasticity, which occurs at a later stage in the healing process, may also require treatment. This pathologically increased muscle tension can be treated pharmacologically (Botox, baclofen). The combination of pharmacological treatment and electrotherapy has proven to be beneficial (Cotoi et al. 2018). Early physiotherapy and occupational therapy are also particularly important for the treatment of symptoms.

Bladder and rectal disorders are alleviated to the greatest possible extent using compensatory techniques. The mostly spastic bladder can be controlled by an indwelling catheter, or by catheterisation several times daily using disposable catheters. Regular urological follow-up visits are particularly important in this case. The flaccid or spastic colon is compensated primarily by regulating the diet, and thus the stool consistency, and by digital stimulation.

Rehabilitation of tetraplegia

Physiotherapy, occupational therapy & further treatment

The therapy is already started as soon as possible during the inpatient hospitalisation. The goal of the therapy is to ensure the maximum independence of the affected person in their everyday life, as well as their social and professional reintegration.

Physiotherapy is mainly concerned with restoring functions, training specific activities, and restoring movement with or without aids. Depending on the severity of the damage, the focus may also be on independent use of a wheelchair or independent movement in bed. A balance between restorative and compensatory measures is the key to ensuring that the affected person can successfully master their daily routine.

Physiotherapy also serves to maintain and improve the pulmonary function. Since pneumonia is considered to be one of the more serious complications and represents a high risk, patients are treated in repeated rehabilitation phases. The consistent therapy aims at improving or restoring functions, thereby minimising the risk of infection.

Physiotherapy and occupational therapy for (incomplete) tetraplegia

Occupational therapy focuses on independence, dressing and undressing, as well as household tasks. Especially in this setting, context factors (such as age, gender, fitness, home life, family environment, etc.) play an essential role in the successful integration of what has been learnt into the daily routine. The provision of aids of any kind can also facilitate everyday life and increase the independence of the affected person.

Future leisure activities constitute another important aspect that is mostly covered by occupational therapy. The therapy sessions often aim to find new hobbies for those affected. Effective structuring of the newfound leisure time is essential, especially if the patient has lost the ability to work.

An interdisciplinary task is the prevention of secondary complications such as:

• pressure ulcers (bedsores) due to reduced mobility
• contractures (painfully rigid joints) due to excessive muscle tension (spasticity)

Whether in the therapy, at home, or in the nursing home, attention must be paid to warning signs. Timely intervention is essential, where required. Special mattresses and splints may be helpful in these cases.

Functional electrical stimulation for (incomplete) tetraplegia

Electrotherapy

The focus is on restoring functions for patients with incomplete tetraplegia The EMG-triggered functional electrical stimulation (EMG FES) enables the affected person to perform everyday exercises through multi-channel stimulation (Popovic et al. 2011).

Functional electrical stimulation is not only used to restore functions, but also to treat spasticity. The treatment is particularly advantageous in combination with Botox, as compared to Botox injections on their own (Cotoi et al. 2018).

Flaccid paralysis at the level of injury is usually the main concern for the affected person due to the strength deficit. The structure can be preserved and the muscle strength improved by stimulating with adapted currents (low frequency, long pulse duration) (Kern et al. 2010). Electrical stimulation may even be applied years after the spinal cord injury (Kern et al. 2002), and even in the case of complete denervation (Kern et al. 2017).

In this context, preventing pain in the subluxated shoulder is the main concern. Treatment with neuromuscular electrical stimulation may help stop the increasing muscle atrophy, which is caused by the (partial) denervation, and thus the subluxation (Koyuncu et al. 2010; Fil et al. 2011).

In the case of complete paralysis or severe damage, the focus is on supporting the upper limbs, which are sometimes still partially innervated. Stimulation should help to train the support function and a functional hand after tendon transplants (Bersch & Fridén 2016).

Functional electrical stimulation is also an important treatment method for patients with paraplegia (Th2-Th5) and quadriplegia (tetraplegia), since they can no longer voluntarily activate abdominal muscles. Stimulation can activate abdominal muscles, which are responsible for forced exhalation and coughing, thus making coughing possible (Gollee et al. 2008).