A wrist fracture is a common injury, often resulting from a fall onto an outstretched hand, affecting one or more of the bones connecting the forearm to the hand. Many people try to determine the severity by attempting to move their fingers, mistakenly believing that movement means the bone is not broken. This self-assessment is a mistake, as the ability to move your fingers does not rule out a significant fracture. The true diagnosis requires professional medical evaluation and imaging, as the structures controlling finger movement are largely separate from the fractured bone itself.
Understanding Wrist and Finger Anatomy
The ability to move your fingers, even with a broken wrist, is due to the distinct anatomical separation between the wrist bones and the finger-moving structures. The wrist is a complex joint made up of eight carpal bones, along with the two forearm bones: the radius and the ulna. A fracture typically involves one of these bones, most frequently the distal radius, which is the forearm bone near the thumb side of the wrist. The muscles that control finger and thumb movement are primarily located in the forearm, not the hand. These muscles are connected to the fingers by long tendons, which pass through the wrist area and into the hand.
The flexor tendons, which allow you to curl your fingers, run along the palm side of the wrist, while the extensor tendons, which straighten your fingers, run along the back. Since the tendons run past the wrist bones to attach to the finger bones, they can often still function even if a wrist bone is broken. Unless the fracture is severely displaced or has directly lacerated a tendon or nerve, the mechanical connection for finger movement remains intact. This explains why a person can often still wiggle their fingers or make a fist despite having a fractured wrist.
Finger Movement After Injury
The misconception that a broken bone means total loss of function is often disproven when an individual can move their fingers after an injury. Movement of the fingers is common with a fracture, especially a non-displaced break where the bone pieces remain aligned. While you may experience pain when trying to move the fingers, the physical action is often still possible. The primary concern of a wrist fracture is bone instability, not the immediate loss of tendon function. Medical professionals often advise keeping the fingers moving while the wrist is in a splint or cast to prevent stiffness and reduce swelling. Using the presence or absence of finger movement to self-diagnose a break is unreliable and delays necessary treatment.
Recognizing a Serious Wrist Fracture
Since finger movement is not a reliable indicator, recognizing a serious wrist fracture requires looking for specific symptoms. The most noticeable sign is severe, persistent pain that does not improve quickly after the initial shock wears off. This pain is frequently accompanied by rapid swelling around the joint.
Another strong indicator is a visible deformity, where the wrist appears bent at an unnatural angle or looks crooked. This suggests a displaced fracture, such as a Colles fracture, where the broken end of the radius tilts toward the back of the hand. Localized tenderness over the “snuffbox” area on the thumb side of the wrist can suggest a scaphoid bone fracture, which can be difficult to see on initial X-rays.
Beyond pain and deformity, look for signs of nerve involvement, such as numbness or tingling in the fingers. A severe break can impact the nerves or blood vessels, manifesting as a loss of sensation or a change in finger color. These symptoms should prompt an immediate visit to a medical facility.
Immediate Care and Seeking Medical Help
Immediate care for a suspected wrist fracture should focus on stabilizing the injury and managing swelling and pain until professional help is available. Gently restrict movement of the wrist using a makeshift splint, such as a rolled-up newspaper or a pillow. This immobilization helps prevent further injury to the soft tissues and nerves.
To control swelling and reduce pain, apply ice to the area for about 20 minutes at a time. The injured wrist should also be elevated above the heart to minimize fluid buildup. Over-the-counter pain relievers can manage discomfort, but this should not replace seeking a medical evaluation.
Seek medical attention quickly, especially if there is severe pain, an obvious deformity, or a loss of sensation in the fingers. Only professional medical imaging, typically an X-ray, can definitively diagnose a fracture and determine its severity. Delaying a diagnosis can lead to improper bone healing, long-term stiffness, or joint complications.