A distal radius fracture (ICD code: S52.5) is commonly referred to as a wrist fracture. It is actually a fracture of the radius, which is also known by its technical term. The ulna, the second bone of the forearm, is not injured in a radius fracture; otherwise, the condition is referred to as a distal forearm fracture.
“Distal” and “proximal” are terms used to more precisely classify and categorize the extremities. Here,
- "distal" means farther from the body (in the arm, closer to the fingers) and
- proximal means closer to the body (in the arm, closer to the shoulder).
What makes a distal radius fracture unique is that the wrist is often involved as well, which carries the risk of impaired wrist mobility. A distal radius fracture differs from a simple radius fracture
- in terms of the fracture site
- and in terms of treatment.
If the radius fracture affects or damages the wrist, surgery is usually necessary.
Conservative treatment—that is, simple immobilization with a cast without surgery—is only possible for very simple fractures (simple radius fracture). However, it is a suitable option if the radius is fractured without displacement or impairment of the joints.
The radius is one of the two bones in the forearm © FGWDesign | AdobeStock
Diagnostics in Orthopedics and Trauma Surgery: Clinical and Radiological
A distal radius fracture is invariably caused by an accident, most commonly a fall onto an outstretched hand. This common bone injury is also accompanied by pain in the affected area, specifically around the wrist. Immediately after the accident, the pain is often mild but intensifies and worsens as swelling increases and a hematoma forms.
In addition, there is a significant restriction in wrist mobility, which is usually due to pronounced swelling and pain. Increased sensitivity to touch and pain when pressure is applied to the joint are also typical signs of a wrist fracture.
Furthermore, the affected arm is often unable to exert as much force as normal. Sensory disturbances may also occur, for example, if a nerve is pinched or compressed as a result of the fracture.
Finally, depending on the severity of the fracture, a misalignment may also be visible, giving the wrist an abnormal appearance.
In extreme cases, open skin wounds and exposed bone fragments may be visible; this is also referred to as an “open fracture.” This is a very serious condition and generally indicates the need for surgical treatment.
Here is a summary of the symptoms:
- Pain on pressure
- Pain with movement
- Swelling of the forearm or wrist
- Possible misalignment
- Functional impairment
- Weakness
- Sensory disturbances
- Skin lacerations and exposed bone fragments
Fractures of the radius usually result from breaking a forward fall with the hands. When falling, most people instinctively reach forward with their hands to avoid landing on their face. Depending on the angle of the fall, the severity of the impact, and the speed, a fall can quickly result in a fracture. In younger people, severe falls during sports are usually the cause. In particular,
- contact sports such as soccer, handball, or basketball, and
- jump-based sports such as the high jump or long jump
- sports with a high risk of falls (inline skating, skateboarding)
carry an increased risk. However, even in low-contact sports such as jogging or cycling, stumbling and falls—due to speed and uneven terrain (e.g., in the woods)—can also frequently lead to a distal radius fracture.
In a distal radius fracture, it is not a bone in the wrist that breaks, but rather the radius near the wrist © yodiyim / Fotolia
In older patients, even minor falls can lead to a fracture due to the often lower bone density (osteoporosis).
Bone density decreases with age, even in the absence of any pathological bone changes. As a result, bones naturally become more unstable with age (i.e., without representing a pathological change) and can break more easily. Strength training for seniors, by the way, can help address this issue and lead to a strengthening of bone structure.
In cases of pathological reduction in bone density—that is, osteoporosis—the bone is weakened beyond normal (physiological) levels and is consequently extremely susceptible to fractures. For this reason, even minor falls can sometimes be enough to cause fractures in older adults. Fractures of the radius following falls from a standing position are very common in this context.
Fractures of the radius near the wrist are classified into two subtypes:
- Colles fracture: Impact with the outstretched hand
- Smith fracture: Impact with the hand flexed.
The Colles fracture accounts for about 90 percent of all radius fractures and is therefore much more common. Although the Smith fracture is much rarer, it requires surgical treatment in the vast majority of cases. This is because the Colles fracture is often stable and can be treated with a cast, whereas the Smith fracture is unstable and repeatedly shifts despite cast treatment. Conservative treatment of a Smith fracture almost invariably leads to wrist osteoarthritis, which is attributable to malunion or nonunion.
A fracture of the radius is a matter for trauma surgery and orthopedics. Patients often receive initial care and examination in the emergency room. First, a history of the patient’s medical background and the mechanism of the injury is taken; then, the forearm is palpated to check for
- swelling,
- tenderness, or
- bruising
are present. In some cases, a cracking sound may also be heard during the examination, which is another strong indication of a bone fracture. Furthermore, in extreme cases, a significant misalignment of the bone and joint may be observed, which is virtually conclusive evidence of a bone fracture. It is also important during the initial examination to check blood flow and sensation in the hand to rule out injury to blood vessels and nerves.
A radius fracture without displacement often delays diagnosis, as many symptoms are absent in this case. Typically, an X-ray can unequivocally reveal the nature of the underlying fracture.
If a complicated fracture is suspected, a computed tomography (CT) scan is also performed in most cases.
Distal radius fractures treated in orthopedics and trauma surgery: Conservative therapy or surgical therapy via reduction
In the case of a so-called simple and stable radius fracture, conservative treatment may be sufficient. A radius fracture is considered stable whenever the fracture ends are well aligned and do not shift relative to one another while in a cast. However, regular X-ray follow-ups are important—initially at short intervals—to monitor the success of the cast treatment and the alignment of the bones. Immobilization with a cast typically lasts for six weeks.
In the case of an unstable fracture, however, the fracture ends cannot be properly reduced, and there is always a risk that the bone ends will shift relative to one another despite being immobilized in a cast. This is always the case when tissue (such as tendons) is located between the bone ends or in the case of a Smith fracture, as described above. Unstable fractures must always be treated surgically; otherwise, there is a risk of wrist osteoarthritis.
What surgical methods are available for distal radius fractures?
The principle behind all surgical procedures here (as with conservative treatment) is that the fracture must first be restored to its correct position through reduction (repositioning). This position should be the normal position. Subsequently, this position must be stabilized, which can be achieved through various approaches.
- Plaster cast immobilization: This is possible and indicated when tissue had to be removed from the fracture gap prior to reduction and the fracture is subsequently well aligned and stable.
- Osteosynthesis: This refers to the fixation and stabilization of the fracture using screws, wires, plates, or other devices that are inserted externally onto or into the body. “Osteo” stands for bone, and “synthesis” for connection or joining.
The following are examples of the most important osteosynthesis procedures:
- External fixator (application of an external metal frame)
- Wire osteosynthesis (often used in children; so-called “pin wires”)
- Screw osteosynthesis
- Plate osteosynthesis (most common procedure)
In each individual case, the most appropriate surgical method must be determined on a case-by-case basis.
Metal plates and screws stabilize a fractured radius © Whyona / Fotolia
Epidemiology and mechanism of injury in distal radius fractures: Associated injuries and closed reduction of distal radius fractures
After surgery, the wrist must be rested for an appropriate period of time. In the meantime, targeted weight-bearing on the surrounding muscle and joint areas should be resumed as quickly as possible.
As part of physical therapy, the range of motion of the fingers, elbow, and shoulder is assessed and restored to normal. Patients should also resume performing light grasping movements as soon as possible and avoid completely immobilizing their arm.
Even after surgery, the success of the procedure is monitored through X-rays. The first X-ray is usually taken on the first day after surgery, when many patients are still in the hospital. For outpatient procedures, appointments for follow-up examinations are scheduled at the time of discharge. Depending on the findings, the date for the next follow-up examination is then determined. In any case, this examination should take place no later than 6–8 weeks after surgery to document the healing of the fracture.
The metal support materials used must be removed after a certain period of time during a minor procedure. The plates used in plate osteosynthesis usually remain in the body for at least 12 months, while wires and screws are removed earlier. This is because wires and screws can also break or migrate outward when subjected to stress, and can cause skin damage. This is generally not the case with plates.
The prognosis for treatment depends on the severity of the fracture. In the case of a severe fracture, long-term complications such as
- chronic pain
- loss of strength, or
- sensory disturbances
. These must then be treated on a case-by-case basis.
However, a distal radius fracture usually heals well, and no permanent damage remains.
How can I tell if I have a wrist fracture?
Typical signs of a distal radius fracture include immediate pain in the wrist, visible swelling, and often a misalignment in which the hand appears displaced relative to the forearm (bayonet position). Movement is barely possible and very painful. Bruising is often present. If there is numbness in the fingers, a nerve (median nerve) may be compressed, which is a medical emergency. An X-ray of the wrist provides a definitive diagnosis.
When is surgery necessary for a distal radius fracture?
Surgical treatment is necessary if the fracture is unstable—that is, if it shifts again after reduction (repositioning). Surgery is also performed in cases of open fractures, if the articular surface is affected by a step greater than 1–2 mm (intra-articular distal radius fracture), or if there are associated injuries such as a tear of the scapholunate ligament. The goal is to precisely restore the anatomy in order to prevent osteoarthritis.
How is the surgery performed?
The gold standard for surgical treatment today is angle-stable plate osteosynthesis. In this procedure, a titanium plate is screwed onto the distal radius through an incision on the flexor side (palmar) or, less commonly, the extensor side (dorsal), thereby stabilizing the fracture. This often allows for early functional exercise without a cast. In cases of very complex comminuted fractures or soft bone, an external fixator (external frame) or Kirschner wire fixation may also be necessary.
How long does healing take?
Bone healing usually takes 6 to 8 weeks. However, it often takes 3 to 6 months for full weight-bearing capacity and range of motion to be restored. After plate osteosynthesis, the wrist can usually be moved gently right away, whereas with conservative treatment, immobilization in a cast for 4 to 6 weeks is recommended.
What are instability criteria?
Criteria for instability help the doctor decide whether surgery is necessary. These include a comminuted fracture site, a shortening of the radius by more than 5 mm, a dorsal tilt of the articular surface by more than 20 degrees, or a concomitant fracture of the ulna, specifically of the styloid process of the ulna. If these criteria are met, there is a high risk that the fracture will slip out of the cast (secondary dislocation).
What are the associated injuries?
Common associated injuries include fractures of the ulnar styloid process (processus styloideus ulnae), tears of the triangular fibrocartilage complex (TFCC), or tears of the ligaments between the carpal bones (e.g., the SL ligament). Nerve injuries (carpal tunnel syndrome) or tendon tears (e.g., extensor pollicis longus tendon) may also occur. These must be taken into account during diagnosis and treatment.
What is CRPS?
CRPS (Complex Regional Pain Syndrome) is a feared complication following distal radius fractures. It involves a dysregulation of the nervous system that leads to severe, burning pain, swelling, skin changes, and restricted movement that are disproportionate to the original trauma. Early treatment with physical therapy and medication is important to prevent chronic damage.
Does the metal need to be removed?
Removal of the plate is no longer absolutely necessary today, provided it does not cause any problems. If tendons (e.g., flexor or extensor tendons) are irritated by the plate or if the plate presses on the wrist, it should be removed after the bone has healed (no sooner than 6–12 months). In children, the plate is almost always removed so as not to interfere with growth.
