The proximal interphalangeal joint refers to the two horizontal lines on the fingers of the index, middle, ring and little fingers, with the proximal interphalangeal joint being located on the proximal side of the palm. This position is composed of the proximal phalanges and the middle phalanges, and plays an important role in the flexion and extension of the hand. When lifting, carrying heavy objects or exerting excessive force and frequent activities, the proximal interphalangeal joint, the joint capsule and the surrounding tendons, ligaments, fascia and other soft tissues may become strained or damaged by strain or inflammation, which may cause some stimulation of the peripheral nerves and pain. Further irritation can lead to significant pain, some with swelling of the interphalangeal joints, and unfavorable movement.