Dr. Bertrand Brugerolle
Médecin-chef, CRF Lay-Saint-Christophe
Strokes (CVA) are acute complications of a vascular disease caused due to a lack of blood supply to a portion of the brain (cerebral infarction) or a ruptured blood vessel (intracerebral hemorrhage). Stroke is the third leading cause of mortality in France, as well as the first leading cause of disability. The most common manifestation of a stroke is hemiplegia (paralysis of one side of the body).
What is a stroke?
In common language, a cerebral vascular accidents are also referred to as 'brain attack' or 'stroke'. The number of new cases each year is estimated to be 100,000 in France, and there are 35,000 annual relapses in post-stroke patients. The number of individuals who have had a stroke is estimated at 500,000 in France. Strokes are commonly seen in males (4 males for 3 females) and more often during winter. The number of cases increases with age; the incidence being 40 cases in 1000 individuals aged over 85.
Cerebral lesions lead to various impairments. Motor impairments are the most common form, however other disorders can be observed such as sensory disorders and cognitive impairments (language, comprehension, memory, perception of time and space)
How does a stroke occur?
The onset can be devastating (signs appear in a few seconds, minutes or hours), immediate or gradual with an unpredictable alteration of consciousness. It immediately leads to one or more neurological deficits depending on the site of the cerebral lesion (focal syndrome). Clinical signs may progress and stabilize or regress.
These examinations affirm the diagnosis and clarify the condition's mechanism.
CT scan (figure 1): Performed in emergency, it distinguishes ischemic (due to vessel obstruction) and hemorrhagic strokes, and clarifies the site, the extent, and the impacts of the cerebral lesion.
Magnetic Resonance Imaging (MRI) is rarely necessary, but was proven useful for some locations (brainstem).
Other examinations are used to validate the stroke mechanism. Examination of the arteries using non-invasive techniques (Doppler and pulsed Doppler ultrasonography) are performed. Radiological examinations of the arteries or angiography are critical when a vascular malformation is suspected, because it enables visualization of the malformation and sometimes its treatment is done through embolization techniques (by the probe used for exploration). Examinations of the heart in search of a potentially embolic heart disease, and high blood pressure are also performed.
Figure 2: Cerebral strokes
Diagram showing the arterial territories of the brain that are affected in focal syndromes.
It depends upon the cerebral vascular territory concerned (figure 2)
Carotid territory (80% of the hemispheric infarctions):
|Left middle cerebral artery||hemiplegia, hemianesthesia, homonymous hemianopsia, aphasia, constructional and gestural apraxia|
|Right middle cerebral artery||Left neglect, anosognosia, hemiasomatognosia, constructional and dressing apraxia|
|Superficial middle cerebral artery||Hemiplegia of the face and arm, and same deficits as above to various degrees|
|Deep middle cerebral artery||Complete hemiplegia|
|Anterior middle cerebral artery||Hemiplegia predominant in lower limb|
Vertebrobasilar territory and posterior cerebral artery
|On the side of the lesion||Paralysis of a cranial nerve|
|On the side opposite to the lesion||Hemiparesis; hemihypesthesia|
Descriptive clinical presentation
Strokes are associated with:
- Motor disorders: the individual initially presents with total paralysis of one side of the body, the muscles are incapable of any activity. Following a few days or weeks, muscle contractions becomes possible again, but this recovering motility is altered and only enables coarse inaccurate of movement. In addition to the motor disorders, are problems with tone which are characterized by resistance to muscle stretching (spasticity), producing the typical hemiplegic attitude: flexion of the upper limb, closed hand, extension of the lower limb;
- Sensory disorders are very common (according to the same physical features as paralysis);
- Visual disorders: impairment of the intracerebral visual pathways is responsible for the loss of vision in one visual hemifield located on the same side as the paralysis (hemianopsia);
- Praxis disorders: discomfort or incapacity in the performance of movements despite the absence of motor disorders;
- Gnosic disorders or sensory integration disorders when peripheral sensory receptors are intact. It is also referred to as sensory and visual agnosia;
- Speech and language disorders: paralysis of the muscles of the palate, tongue, and jaws leads to speech difficulties called dysarthria; comprehension and/or expression difficulties characterizes aphasia. This disorder may be predominant in the motor aspect with preservation of a relatively good comprehension. Comprehension is sometimes very severely affected, with preservation of a discourse riddled with jargon and hardly comprehensible. These difficulties concern both the oral and written aspects of language;
- Depression syndromes are common (30%), as well as issues related with recent memory.
A very complex network of arteries carries blood supply to the brain. Impairment of such arterial ramifications affects a specific brain area and produces particular clinical signs (hemiplegia when the motor area is affected, etc.)
- Diagram of the arteries in the brain: four main axes
- Circle of Willis and vessels of the base of the brain
- Carotid system
What causes a stroke?
Strokes are caused by the interruption of blood flow (ischemia) in a cerebral territory (cf. fig. 3) provoking its destruction. The cerebral tissue is very sensitive to any reduction in the blood flow and will definately necrotize (die) if the lack of blood supply last longer than 6 minutes. There are two main causes of ischemia (see below):
- Obstruction of a blood vessel;
- Disruption of a blood vessel (hemorrhagia).
Aetiologies and risk factors
Causes of Obstruction (ischemic strokes)
- Atherosclerosis: It is a lesion of the artery walls; causing a reduction of the internal diameter of vessels or total obstruction. Fragments may dislodge from the atheromatous plaques to become small emboli (foreign bodies circulating in vessels) that will most likely clog small vessels downstream;
- Embolic thrombosis results from the formation of small clots in cardiac chambers causing a cardiac rhythm disorder (arrhythmia).
Risk factors of vessel obstruction can be identified as
- Major risks: high blood pressure, diabetes, aging, personal or family histories of stroke;
- Minor risks: dyslipidemia (cholesterol level in particular), tobacco use, oral contraception, obesity, and alcohol abuse.
Causes of Intracerebral Hemorrhage (hemorrhagic strokes)
Intracerebral hemorrhage is caused by a sudden rise in blood pressure, trauma, or disruption due to an arterial malformation (angioma, aneurysm).
How does the disease progress?
The mortality rates are very high during the initial stages; one patient out of 10 dies on the first day, and 1 out of 3 or 1 out of 2 during the first month after an incident. After one year, survivors gain back their normal life expectancy similar to individuals of the same age.
All post-acute patients experience full spontaneous recovery and improvement of function. This recovery may vary from one patient to another significantly and it may be unpredictable. Rehabilitation that is started early does not change the course of spontaneous recovery. Reacquisition of neurological control, especially a gross control, in the weeks and months following the stroke is unquestionable. Functional compensations are established and developed, for example: use of the left hand to write in case of hemiplegia on the right side.
A prognosis of recovery is extremely hard to establish. Some signs are pejorative, such as persistent postural deficits (poor equilibrium in sitting), hemineglect, and massive impairment of deep sensibility. Patients with left side hemiplegia display with significant body image disorders and attention deficits, and often experience a later recovery. While age is not a priori a factor for inappropriate prognosis, the number of failures increase with age due to associated disorders (cardiac, respiratory, etc.) and underlying depressive syndrome. The aetiology (causes) of the stroke has an impact: hemorrhages are more severe at the beginning, but are generally less invalidating than ischemia for those who survive the initial phase.
What are the disabilities?
- Potential full recovery including fine finger movements;
- The quality of movements of the upper extremity may be poor, with absence of finger dissociation, grip, and release (opening of the hand). Recovery is more significant in lower limbs, even if impairments of the dorsiflexor muscles are usually persistent;
- Major global impairments may be persistent, in complete upper limbs, and some movements may be possible in the lower limbs, but insufficient to enable walking.
- Walking with or without cane is possible for four patients out of five individuals. One out of five becomes permanently dependent on a wheelchair. These patients require the help of a caregiver to perform their activities of daily living;
- Independence in the activities of daily living is achieved for four patients out of five;
- Full recovery of hand function is rare (15%-30%);
- Communication disorders may remain a primary concern with some speech disorders and comprehension difficulties. Compensatory strategies are often implemented using sign language or facial expression.
Beyond initial complications of decubitus position (phlebitis, pulmonary embolism, respiratory and urinary tract infections, etc.); some effects of the stroke may be persistent: painful shoulder, drop foot, and spastic equinovarus. Finally, stroke relapses may occur.
Complications of Stroke
- In decubitus position: This involves life threatening issues that are critical to the initial phase.
- Painful shoulder: it is very common and often attributed to early trauma (traction on the hemiplegic arm, partial dislocation of the humeral head by the arm weight when getting in and out of bed or chair). Treatments combine preventive measures (avoiding tractions and improper positioning), simple mobilization therapy, intra-articular injections, and functional electrical stimulation.
- Spastic equino varus: This typical deformity is seen in patients who resume walking and increases with speed. The surface area of support is on the anterior and outer edge of the foot. Treatment combines mobilization and muscle relaxants, electrical stimulation, orthotic support or orthopaedic shoes, and surgery if fitting difficulties persist (tendon stretching and transfer).
What are the suggested treatments and management strategies?
In emergency: basic life support and control of brain oedema (resuscitation); specific treatments according to the aetiology of the condition (anticoagulants, clot-dissolving drugs, vascular surgery in some cases); physical therapy interventions (mobilization, proper positioning, avoiding shoulder pain, and prevention of pressure sores).
During the rehabilitation phase, patient management is multidisciplinary
- Physical therapy: neuromuscular rehabilitation facilitating useful movements and inhibiting parasitic ones. In most cases, treatments to lower limbs mainly result in the patient resuming walking;
- Occupational therapy: regaining independence, re-lateralization if necessary, treatment of neuropsychological disorders, potential selection of technical aids, home conversion, help for a third party for people with severe forms of disabilities. Retraining of upper limbs sometimes enabling a full recovery;
- Speech Therapy: treatment of oral and written communication disorders (speech comprehension and production);
- Prescription of orthoses: stabilization splints, drop foot braces, walking aids (single-tip, tripod or quad canes), hemiplegic wheelchairs (one-arm driven), and orthopaedic shoes sometimes required.
- Stroke research addresses different aspects: prevention (reduction of risk factors, especially high blood pressure screening and treatment); better familiarity with the lesion, more effective treatment of causes; initial medications limiting the extent of lesions; more effective rehabilitation treatment of cognitive disorders (assessment of disorders and treatment adjustment according to that assessment).
Living with the side effects of a stroke
The overwhelming majority of hemiplegic individuals return home. Final discharge is the logical outcome at the end of outpatient rehabilitation. Maintaining the acquired performance levels after discharge requires daily practice of adaptive training in home settings (improvement is often noticed), medical supervision in order to prevent and reduce the risk of relapse, maintaining contact with the outside world to prevent de-socialization, as well as orthopaedic supervision may be required.
Vascular hemiplegia may leave side effects that are consistent with normal activities, even with sports.
For more information:
Albert A., Rééducation neuromusculaire de l'adulte hémiplégique. Paris, Masson, 1969, 265 p. (physicians and paramedics)
Girard R., Vivre avec une hémiplégie. Handicap et réadaptation, SIMEP 1987.
Pelissier J., Hémiplégie vasculaire de l'adulte et médecine de rééducation. Paris, Masson, 1988, 370 p. (physicians and paramedics).