Injury to the median nerve in the hand is manifested as: thumb abduction dysfunction and thumb and index finger pinching dysfunction due to thumb short abductor palsy, sensory deficits in the radial half of the palm, thumb, index, middle and ring finger radial half of the palm, thumb interphalangeal joint and index, middle and ring finger radial half of the proximal interphalangeal joint to the distant, mainly manifested as loss of sensation in the index finger. So what is the differential diagnosis of loss of sensation in the index finger? The following is a brief introduction for you. Differential diagnosis of loss of sensation in the index finger: 1, sensory disorders: sensation is the direct reflection of various receptors to various stimuli in the body in the human brain. Sensory disorder is one of the common symptoms in neurological disorders. 2, sensory separation: If there is a disease that destroys the posterior cord of the spinal cord, so that deep sensation can not be transmitted upward, then you can not feel the position of the limb, and can not figure out whether it is flexion or extension. Because of the loss of knowledge of their own limbs, they appear to move awkwardly and walk wobbly. The phenomenon of sensory dissociation is of great importance in the diagnosis of neurological diseases. The doctor determines what is diseased according to the form of distribution of various sensory disorders, which is called localization diagnosis. 3, numbness, pain or abnormal sensation in the distal extremities: sensory-type peripheral neuropathy, mainly manifested as numbness, pain or abnormal sensation of varying degrees starting in the distal extremities. The typical symptoms of median nerve injury are loss of sensation in the radial 3.5 fingers and inability to fully flex the index and middle fingers. There is a “sworn hand”-like deformity.