From the Guidelines
The protruding joint on the wrist is called the ulnar styloid process. This bony prominence is located on the outer edge of the wrist on the pinky finger side and is part of the ulna bone in the forearm. The ulnar styloid process serves as an attachment point for ligaments that help stabilize the wrist joint and is an important anatomical landmark. It becomes particularly noticeable when you rotate your hand or bend your wrist. Sometimes people mistake this normal anatomical feature for a ganglion cyst or injury, but it's a natural part of human anatomy. If the ulnar styloid process becomes painful or more prominent after an injury, it could indicate a fracture or other damage that would require medical evaluation, as discussed in the context of acute hand and wrist trauma 1. Under normal circumstances, this bony prominence should not cause any discomfort or functional limitations. In cases of suspected wrist fracture or trauma, radiography is always indicated as the initial imaging, and careful attention to radiographic positioning is necessary to assess carpal instability 1. However, the ulnar styloid process itself is a normal anatomical feature and not typically a cause for concern unless it becomes painful or prominent after an injury. Key points to consider include:
- The ulnar styloid process is a normal bony prominence on the outer edge of the wrist
- It serves as an attachment point for ligaments that stabilize the wrist joint
- It can become noticeable when rotating the hand or bending the wrist
- Pain or prominence after an injury may indicate a fracture or other damage requiring medical evaluation, as guided by radiographic assessment 1
From the Research
Wrist Anatomy
- The wrist is a complex joint that consists of multiple bones, including the scaphoid, lunate, and distal radius.
- The distal radius is the bone in the forearm that forms the wrist joint, and it has a protruding joint on the wrist known as the radial styloid process 2.
- The radial styloid process is a bony landmark that can be palpated on the wrist and is used as a reference point for locating other carpal bones, such as the lunate and capitate 2.
Protruding Joint on Wrist
- The protruding joint on the wrist is likely referring to the radial styloid process, which is a bony prominence on the distal radius that can be felt on the thumb side of the wrist 2.
- The radial styloid process serves as an attachment point for ligaments and tendons that support the wrist joint and provide stability to the forearm 3.
- Injury to the radial styloid process or the surrounding ligaments can lead to wrist instability and other complications, such as distal radioulnar joint (DRUJ) instability 3.