Uncontrolled shaking of the index finger may be a symptom of Parkinson’s and cerebellar diseases, or it may be caused by strain, neuropathy, nerve compression, vascular lesions and other factors. 1. Parkinson’s disease: mainly resting tremor, the patient’s finger shaking is obvious when at rest, and is reduced when in motion. 2. Cerebellar disease: mainly intentional tremor, the patient’s finger tremor in motion, disappears at rest. 3. Strain injury: If the patient suffers from muscle strain of the finger due to long-term work, the phenomenon of uncontrolled shaking of the index finger may occur. 4. Neuropathy: If the patient suffers from diabetes or electrolyte disorders caused by inflammation and other factors, it may cause peripheral neuropathy, which may lead to the symptoms. 5. Nerve compression: If the patient suffers from carpal tunnel syndrome or cervical spondylosis, etc., the nerves may be compressed and the index finger tremor may occur. 6. Vascular lesions: If the patient has hardening or narrowing of the blood vessels in the upper limbs, it may cause this symptom. There are many factors that cause involuntary shaking of the index finger, patients should go to the hospital in time to check the cause of the disease and consult the doctor after clarifying the cause of the disease.