A pediatric wrist X-ray is a standard, quick imaging procedure used to evaluate the bones and joints in a child’s wrist following an acute injury, such as a fall. Wrist fractures are among the most frequent bone injuries seen in children, often occurring when a child attempts to break a fall with an outstretched hand. The X-ray provides immediate, detailed images of the bone structure, which is necessary for accurately diagnosing a fracture or other significant trauma near the joint.
Preparing for the Procedure and Managing Concerns
The X-ray process is quick, typically taking only a few minutes. The technologist usually takes at least two views of the wrist—a posteroanterior view (palm down) and a lateral view (side view)—to ensure the entire joint is visible from different angles. Obtaining a clear image depends on the child remaining perfectly still during the brief exposure, which is sometimes challenging when the wrist is painful.
Healthcare providers use various methods to help a child stay still, including simple distraction techniques like conversation or toys. A parent may be asked to help gently hold the child’s arm or hand in position, using a protective lead apron. Pediatric X-rays use a very low dose of radiation, and protocols are strictly followed to minimize exposure, addressing common parental concerns.
The principle of “As Low As Reasonably Achievable” (ALARA) ensures the lowest possible radiation dose for a diagnostic image. Specialized equipment and techniques limit the X-ray beam precisely to the area of interest. Lead shielding may be used over other sensitive areas of the body, like the torso, to provide extra reassurance.
The Role of Growth Plates
A fundamental difference between a child’s skeleton and an adult’s is the presence of growth plates, or physes, located at the ends of long bones. These physes are areas of developing cartilage responsible for bone lengthening and appear on an X-ray as dark, translucent lines at the end of the bone shaft. Because cartilage is not yet fully hardened, these areas are often weaker than the surrounding bone or ligaments, making them a common site for injury.
An injury that might only sprain a ligament in an adult can cause a fracture through the growth plate in a child. Fractures involving the physis are often classified using the Salter-Harris classification, which describes the location and pattern of the break relative to the growth plate. This classification is important because it helps predict the risk of future growth disturbance.
Interpreting an X-ray with an open growth plate can be complex because the normal appearance of the physis can sometimes mimic a fracture. As a child ages, the growth plates gradually ossify, turning into solid bone and disappearing on the X-ray, typically closing around age 14 to 16. Until this ossification is complete, any fracture near the wrist requires careful assessment to ensure the integrity of this specialized cartilage layer.
Identifying Common Wrist Injuries
One common injury is a Torus fracture, also known as a buckle fracture, which results from a compressive force, often from a fall. This injury appears as a subtle bulging or wrinkling of the bone cortex, rather than a full break across the bone shaft.
Another frequent finding is a Greenstick fracture. The bone bends and cracks on one side, typically the tension side, but remains intact on the opposite side. Both Torus and Greenstick fractures are considered incomplete fractures, reflecting the bone’s greater elasticity compared to adult bone.
When a force is great enough, a complete fracture can occur, where the bone is broken into two or more separate pieces. These are often transverse fractures near the end of the radius bone, called distal radius fractures, and may be displaced or out of alignment. The X-ray precisely shows the alignment of the fractured pieces, which guides the medical team in deciding if the bone needs to be manually repositioned.
Next Steps Following the Diagnosis
Once the X-ray confirms a diagnosis, the next steps focus on stabilizing the injury. Most simple fractures, like non-displaced buckle or greenstick fractures, are treated with immobilization using a splint or a cast. This is typically worn for four to six weeks to hold the bone fragments in a stable position while new bone forms.
For fractures that are significantly displaced or involve the growth plate, a procedure known as closed reduction may be necessary to realign the bones without surgery. A cast is then applied to maintain the corrected alignment. Follow-up X-rays are routinely scheduled, often within one to two weeks, to confirm the fracture fragments have not shifted within the cast.
A referral to a pediatric orthopedic specialist may be necessary for complex injuries, such as those crossing the joint surface or growth plate. Long-term monitoring with subsequent X-rays may be recommended in cases of growth plate injury to ensure the bone is continuing to grow and develop normally.