Partial paralysis is a condition that describes a muscle or group of muscles that is not completely paralyzed. Unlike total paralysis, where movement is not possible, with partial paralysis, the muscles, to some extent, can still produce movement. This condition is usually caused by illness, injury, or stroke. Certain types of poisoning can also cause the condition.
Stroke victims often suffer from some form of paralysis, both total and partial. Strokes generally occur when a blockage or bleeding in an artery cuts off the supply of oxygen to the brain. Sometimes this can cause damage that can be centralized in a specific part of the brain. The death of brain cells in the affected region can cause nerve damage, which can interrupt or weaken the signals that nerve endings send to specific muscle groups. In these cases, the brain may signal a hand to make a fist, but the muscle group may interpret this as a mere signal to move a finger.
Brain injuries that occur near the bottom of the skull are the most common type of brain injury that can lead to partial paralysis. These injuries often cause partial paralysis of the face and can affect swallowing, speech, and eyelid movement. Often times, patients suffering from this type of injury can use muscle groups on only one side of the face, while the other side can function normally. This condition is sometimes permanent, but in many cases, with proper therapy, muscle function is restored.
Spinal cord injuries account for the vast majority of cases associated with partial paralysis. This condition is also known as an "incomplete" spinal cord injury. When the spinal cord is injured, it can affect nerve signals anywhere below the point of injury. These injuries can cause partial paralysis in many different parts of the body. In some cases, the spinal cord heals and nerve and muscle functions return to normal, but depending on the severity of the injury, the paralysis can become a permanent condition.
Poisoning is sometimes the cause of partial paralysis. Lead poisoning, for example, can cause the condition, however, due to health and safety regulations that control human exposure to lead, this is no longer a common occurrence. Diseases that can cause partial paralysis include Bell's palsy, Lyme disease, and Alpers syndrome. In addition to experiencing incomplete muscle movements, people suffering from these diseases may also experience pain in the affected area.