Pathologic signs include Babinski’s sign, Oppenheim’s sign, and Gordon’s sign, which are examined at the ankle joint at the foot and calf of the patient. If the pathological signs are positive, it indicates damage to upper motor neurons, such as lesions in the head, lesions in the cervical spine, and lesions in the lumbar spine. When there is a lesion in the brain and a lesion in the spinal cord, this can lead to positive pathology, decreased muscle strength and increased muscle tone in the extremities. In the case of peripheral nerve injury, the pathology is generally negative, and the muscle strength and tone of the extremities are reduced, mainly in the form of flaccid paralysis. For example, nerve injury in the lower extremity, sciatic nerve injury, or ulnar nerve injury in the upper extremity.