Flexor finger is mainly characterized by shortening of the superficial flexor muscles. The cause of the deformity is not clear, but it is mostly due to the irregularity of the starting point of the superficial muscles, which can be caused by the superficial flexor ring or the earthworm muscle. It is often accompanied by shortening of the skin, and the function of finger extension will be limited to a certain extent. So, how to check the flexor digits? The following is the examination method of flexor finger: Flexor deformity often occurs in the little finger, occasionally involving the ring finger, more than half of the bilateral, flexion often occurs in the proximal interphalangeal joints, when accompanied by the metacarpophalangeal joints or the wrist antagonistic dorsiflexion. Flexion of the fingers is progressive by the age of 10 years, often with a family history, initially unremarkable, and gradually worsening and becoming important to parents. It is often associated with other generalized syndromes such as doun syndrome, klinefelfer syndrome, several common facial syndromes, and sometimes with crooked deformities. Flexion refers to changes in the fingers that occur as a result of flexion deformities. Flexion of the fingers, often with a family history, is initially unremarkable and gradually worsens with flexion, often accompanied by other generalized syndromes such as Doun syndrome.