Cone bundle signs, also known as pathological reflexes, include Babinski’s sign, Chaddock’s sign, Gordon’s sign, Oppenheim’s sign, and Hoffman’s sign. The most common cause of positive cone beam sign is corticospinal tract injury, which can be seen in cerebral infarction, spinal cord lesion, etc. However, children under 1 year old may also have physiologic positive cone beam.
1. Cerebral infarction: patients with cerebral infarction often present with symptoms such as limb weakness, sensory impairment, and slurred speech, etc. Positive pathologic signs can be found on the affected side of the limb during physical examination. This is mainly because cerebral infarction may damage the central motor neurons on the opposite side of the brain, thus producing a positive pyramidal tract sign on one side.
2. Spinal cord lesions: Spinal cord tumors may cause nerve root irritation if they grow in tissues close to the spinal cord. When the spinal cord is partially compressed, there will be motor deficits in the ipsilateral limbs below the plane of compression and sensory deficits in the contralateral limbs, which will also produce a positive sign of pathology on one side.
3. Physiologic positivity: Physiologic pyramidal fascicle positivity may also occur in children less than 1 year of age. In infants and young children, because the pyramidal tract is not yet well developed, the above reflexes can occur and are not pathologic. However, it is common for both sides of the pyramidal tract to be positive, and if only one side is positive, it is recommended that a doctor be consulted to determine if there is any abnormality.
If only one side is positive, it is recommended to consult a doctor to find out the cause of the reflex.