The term 'clonus' refers to involuntary, alternating contractions and relaxations observed in the muscles. An injury to the brain or spinal cord, stroke, multiple sclerosis, cerebral palsy, hepatic encephalopathy, paraplegia, etc., are some of the contributing factors. It can be diagnosed through the ankle clonus test, wherein doctors look for involuntary muscle contractions in the foot.
The ankle clonus test is a diagnostic test wherein doctors induce dorsiflexion (flexing the foot back and forth) to look for abnormal reflex movements of the foot. Deep tendon reflexes are used to understand the response of the muscles. The test is very simple to perform. The doctor will ask the patient to relax, after which the knee will be kept in a partly flexed position. The foot will be quickly moved to a dorsiflex position, that is, the foot will be gently pushed backwards. The foot will be released, after which doctors will look for rhythmic clonus movements. If more than 3 beats are observed, the reflexes are termed as hyperactive without clonus. In case of more than 4 beats, it is called hyperactive with clonus. If there are more than 5 beats, further tests would be needed to ascertain if the person has a neurological problem.
This test is conducted for detecting cerebral palsy in infants. Some of the children who show such abnormal movements in the first year, might develop cerebral palsy. During the test, the foot of the child is moved to the dorsiflexion position. The doctor then observes the motion after the foot is released. He looks for alternating contraction and relaxation of muscles that cause the foot to repeat the motion on its own.
The treatment involves the use of drugs that help control the motor neurons. Nerve blocks are also used at the muscle/motor point and peripheral nerves to curb the vibrations. In case of spinal injury, surgery is suggested as a treatment so as to release the pinched nerves. Spinal disc herniations too require surgery. Physical therapy would also prove to be helpful in its treatment. Apart from that, the use of walking aides or walking sticks is advised to patients who have problems maintaining their gait.
The ankle clonus test is an effective diagnostic tool that can help in the detection of neurological disorders that cause the foot to jerk and twist involuntarily. These conditions cause loss of balance and problems while walking or standing, which might cause discomfort to the patient. Proper diagnosis and treatment is required for alleviating the symptoms.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.