Fractures of the lower end of the radius mainly present as swelling and significant pressure pain in the wrist. Fractures of the distal radius are extremely common, accounting for about 1/10 of usual fractures. mostly seen in older women, children and young adults. The fracture occurs within 2 to 3 cm of the distal radius. It is often accompanied by damage to the radial carpal joint and the lower ulnar radial joint. What are the causes of swelling and pressure pain in the wrist? Fracture of the radius: it occurs mostly at the distal end and is extremely common, accounting for about 1/10 of usual fractures. it is mostly seen in older women, children and young people. The fracture occurs within 2 to 3 cm of the distal radius. It is often associated with damage to the radial carpal joint and the lower ulnar radial joint. The radius, one of the two bones of the forearm, is divided into one and two ends. The upper end forms a flat round radial head with a concave radial head concavity above the head, which is associated with the humeral tuberosity. The circumference of the radial head has a circumferential articular surface, which is associated with the radial notch of the ulna. The neck of the radius is smoothly reduced below the radial head, and there is a large rough elevation below the neck called the radial ramus, which is the resistance of the biceps brachii. The medial margin is sharp, also known as the interosseous ridge, and is opposite to the interosseous ridge of the ulna. The rough surface at the midpoint of the lateral surface is the ramus of the pronator teres. The inferior end is particularly inflated and subrectangular. The distal side is smoothly concave and is the carpal articular surface, which is associated with the proximal carpal bone. The medial side has an ulnar notch and is associated with the ulnar head. The lateral side is protruding downward and is called the radial styloid process, which is approximately 1 to 1.5 cm lower than the ulnar styloid process. It is the most common, mostly due to indirect violence, and was described in detail by A. Colles in 1814. The fracture is caused by a fall with the wrist in dorsal extension and forearm rotated anteriorly and the palm of the hand on the ground, with violence concentrated on the distal cancellous bone of the radius. The distal end of the fracture is displaced dorsally and radially. In children, the epiphysis may be separated, while in the elderly, due to osteoporosis, the fracture can be caused by a slight external force and is often a comminuted fracture, with the fracture end shortened due to impaction. Comminuted fractures may involve the articular surface or combine with ulnar stem avulsion fractures and lower ulnar radial dislocation. Lower ulnar radial dislocation: The function of the lower ulnar radial joint is to stabilize the rotation of the radius at the distal end of the ulna. The main stabilizing factors are: the ulnar collateral ligament, which attaches to the tip of the ulnar styloid process and ends at the pisiform and triangular bones, the triangular cartilage disc, which attaches from the base of the ulnar styloid process to the edge of the ulna and the radial recess; the ulnar and posterior ulnar radial ligaments, which are partially connected to the joint capsule, the anterior rotator muscle, part of the surface of the distal radius and the ulna and the interosseous membrane. Lower ulnar radial dislocation can be associated with Colles fracture, Smith fracture, and Galazzi fracture, but in many cases it can also occur alone. The diagnosis of inferior ulnar radial dislocation is often missed by physicians with little clinical experience, therefore, the diagnosis of this dislocation must be based on clinical manifestations, and bilateral contrast radiographs should be used as much as possible to detect and solve difficult problems.