Cardiovascular accident (CVA) is a disease defined as a sudden neurological deficit (e.g. weakness, loss of sensation or other) due to a vascular cause. The deficit must last for longer than 24 hours and is of sudden onset. A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue (cerebral infarction) and causing sudden symptoms.
Pathophysiologically, CVA can be classified into two processes:
- Ischaemic (85%): can be due to a thrombus (a clot forming in one of the blood vessels supplying the brain); or due to an embolus – a clot which travels from another site (usually the heart) to block off one of the arteries in the brain.
- Haemorrhagic (15%): this is due to rupture of one of the arteries in the brain – usually due to an aneurysm (an outpouching of an artery – causing a point of weakness).
There are several other types – including dissection (splitting) of the wall of one of the blood vessels to the brain, or trauma, and others – but they make up a very small percentage. A TIA (or transient ischaemic attack) has the same symptoms as a stroke, but the neurological deficit lasts for less than 24 hours – i.e. the person recovers completely within that time.
Symptoms of CVA occur suddenly and can include muscle weakness, paralysis, abnormal or lost sensation on one side of the body, difficulty speaking, confusion, problems with vision, dizziness, and loss of balance and coordination.
As a podiatrist it is important to ascertain the cause of the stroke from the medical history. If vessel disease is the underlying pathology, there is reason to assume similar vascular manifestations are occurring in the lower extremity. Podiatrists also have a role in examining and treating the biomechanical complications that CVA victims often have.
Symptoms which may affect the foot and its biomechanics include muscle atrophy (wasting), paralysis (loss of nerve control and sensation) or paraesthesia (altered sensation). These symptoms can often lead to a secondary condition known as foot drop.
Foot Drop (flaccid paralysis)
Foot drop can be defined as a significant weakness of ankle and toe dorsiflexors. The foot and ankle dorsiflexors include the tibialis anterior, extensor hallucis longus, and extensor digitorum longus. These muscles help the body clear the foot during swing phase and control plantar flexion of the foot on heel strike. This is sometimes referred to as steppage gait, because the patient tends to walk with an exaggerated flexion of the hip and knee to prevent the toes from catching on the ground during swing phase.
Spastic Paralysis (muscular hypertonicity)
Increased and involuntary stimulation and weakness of the opposing musculature of each side of the legs often results in an equinovarus deformity (foot twisted so that weight is taken on the outside of the foot). This makes walking and balancing difficult combined with difficulty clearing the ground when swinging the leg through. Furthermore, high pressure on the outside of the foot can lead to severe calluses and even skin ulceration.
- Footwear advice
- Orthotic therapy
- Custom AFO’s (ankle foot orthoses)