The Gordon finger spread sign is a reflex that can only be elicited under pathologic conditions. It is considered an uncertain pyramidal tract sign and may also provide evidence of autonomic hyperexcitability.
What is the Gordon finger spread sign?
In a healthy individual, pressure on the pea bone has no effect. Under pathologic conditions, pressure is followed by extension and spreading of the fingers of the affected hand. The Gordon finger spread sign was named after the American neurologist Alfred Gordon (1874-1953). In English, the reflex is also known as Gordon’s finger phenomenon. In this reflex, pressure is exerted on the os pisiforme (the round pea bone). Under pathological conditions, this pressure causes extension and spreading of the fingers of the affected hand. In healthy people, the finger spread sign usually cannot be triggered. It is considered an uncertain pyramidal tract sign and provides clues to diseases of the nervous system.
Function and task
Reflex testing, and thus testing of the Gordon finger spread sign, is part of the general physical examination and, in particular, part of the neurologic examination. Reflex testing involves both checking for physiologically present reflexes and detecting pathologic reflexes. The result of checking reflexes is also called reflex status. The examination is usually performed with a reflex hammer. Most reflex hammers have two rubber inserts of different sizes on their upper side. In the Gordon finger spread sign, the smaller of the two rubber inserts is used. With this, the examiner applies pressure to the os pisiforme. The Os pisiforme functions as the sesamoid bone and is incorporated into the tendon of the ulnar hand flexor (Musculus flexor carpi ulnaris). It belongs to the carpal bones. In a healthy person, pressure on the pea bone has no effect. Under pathological conditions, pressure is followed by extension and spreading of the fingers of the affected hand. The Gordon finger spread sign is always tested in lateral comparison. Documentation of the reflex response is categorized as normal, diminished, attenuated, increased, or absent. Under normal conditions, the response would have to be categorized as attenuated or absent. If a response to pressure on the os pisiforme is found on one or even both sides, it is referred to as a positive Gordon finger spread sign. A positive Gordon finger spread sign is indicative of damage to the pyramidal tract. The pyramidal tract is a nerve pathway in the brain and spinal cord that is responsible for transmitting the impulses of voluntary motor activity. The pyramidal tract begins in the motor cortex of the parietal cortex. The fibers of the pathway run through all brain sections. In the medulla oblongata, the fibers of the pyramidal pathway cross to the opposite side. The pyramidal tract usually terminates in the spinal cord at the motor neurons of the anterior horn. Because a positive Gordon finger spread sign provides evidence of pyramidal tract damage, it is one of the pyramidal tract signs.
Diseases and ailments
The Gordon finger spread sign becomes positive when there is damage to the pyramidal tract. Such damage, with disturbances in fine motor skills, weakness in voluntary movements, mass movements, and spastic increases in tone, is also known as pyramidal tract syndrome. The pyramidal tract in the brain can be damaged, for example, by a stroke. In a stroke (apoplexy), there is reduced blood flow to brain tissue. This tissue is damaged or even dies. The cause of a stroke can be a vascular occlusion. A cerebral hemorrhage can also result in an apoplexy. Typical symptoms of a stroke are hemiplegia, speech difficulties, nausea or loss of consciousness. Multiple sclerosis (MS) can also result in a positive Gordon finger spread sign if the pyramidal tract is involved. It is a chronic disease with multiple inflammations of nerve fibers. The myelin sheaths are particularly affected. The myelin sheaths serve as electrical insulation for the nerve fibers. In MS, there are numerous such inflammations. They are found in the brain and spinal cord. The symptoms of multiple sclerosis are very diverse, so that there are often problems with the diagnosis.For example, visual disturbances, swallowing and speech disorders, gait instability, incontinence or depressive moods can occur as part of the disease. Another disease of the nervous system that also affects the pyramidal tract is amyotrophic lateral sclerosis (ALS). Like multiple sclerosis, ALS is a chronic inflammatory disease. In this case, the motor neurons are affected. Motoneurons are nerve cells that are responsible for muscle movements. Both the motoneurons in the brain and the motoneurons in the anterior horn cells of the spinal cord can be affected. Degeneration of these motor nerve cells results in increasing muscle weakness and atrophy. Paralysis and paresis are the result. Increased muscle tone can also result from damage to the first motoneuron. In this case, the Gordon finger spread sign would also be positive. As the disease progresses, gait disturbances, speech disorders, or dysphagia may occur. Patients are severely limited in their coordination and often require assistance with activities of daily living. The disease is not curable. Therapy is aimed exclusively at alleviating the symptoms.
