What is Wrist Fracture?
A distal radius fracture, or a broken wrist, happens when the main large bone in the forearm, called the distal radius, gets broken. The break could include the joint of the wrist, the joint where the two bones of the forearm meet, or the smaller bone in the forearm, the ulna. Younger people typically get this kind of injury from high-energy events, like car accidents or sports, while older people more often get it from lower-energy events, like falls.
Some of the signs of a wrist fracture are sudden severe pain and swelling in the wrist. If the fracture doesn’t receive treatment, it can lead to serious health problems. The approaches to treat a broken wrist can either be non-surgical or surgical, and the choice among these depends on numerous factors.
What Causes Wrist Fracture?
Distal radius fractures, or broken wrists, usually happen because of force applied to the wrist. What happens and how bad the break is can be influenced by the strength of the bone, how the wrist was positioned, and how much force was used. Most often these fractures happen when someone falls and tries to brace themselves with their hands stretched out.
This kind of injury, often called a “fall onto an outstretched hand” or FOOSH, can cause the back part of the wrist, which is usually thinner and weaker, to compress or ‘give way’. Meanwhile, the front part of the wrist, which is usually stronger, pulls apart under tension. This results in a typical ‘triangle’ of bone damage with smaller pieces on the back and a point towards the front. If the inner part of the bone gets compressed, it can affect the wrist’s stability. High-energy injuries like from a car accident can cause severe displacements or shattered bones in a fractured wrist.
Younger people often break their wrists from falling from a height, car accidents, or sports injuries. Older people usually break their wrists from falling from a standing position.
Risk Factors and Frequency for Wrist Fracture
A distal radius fracture, which is the most common type of break in the upper arm, can happen to anyone, regardless of their age or health status. This kind of fracture is the leading orthopedic injury and its frequency is increasing. Each year in the United States, more than 450,000 of these fractures occur. This means they make up about one-sixth of all fractures treated in emergency rooms.
Typically, younger patients get these fractures from intense, high-energy accidents, while older patients usually get them from less intense, low-energy falls. The rate of these fractures in the older population goes up with age, similar to the increase seen with hip fractures. That happens especially when the bones become less dense, a condition known as osteopenia.
There are certain factors that increase the risk of getting this type of fracture for older individuals. If you fall into any of the following categories, you might be at a higher risk:
- Having decreased bone mineral density
- Being a woman
- Being white
- Having a family history of these fractures
- Experiencing early menopause
Signs and Symptoms of Wrist Fracture
Patients with wrist injuries typically show various signs such as a deformed wrist, a displaced hand compared to the wrist, swelling, and pain when moving the wrist. They may also have tenderness and skin discoloration around the injured area. It’s important to understand how the injury occurred because it provides a clue about the extent of the injury. Also, knowing the patient’s general health condition and job requirements can help doctors determine the right treatment. Conditions like osteoporosis, diabetes, and tobacco use could affect how the patient heals.
The doctor should conduct a thorough physical examination. They should look at:
- Condition of the skin and soft tissue around the injury
- Quality of blood flow and pulse in the injured area
- Nerve function
- Sensitivity to touch
- Function of the hand muscles
- Particularly, the function of the median nerve, because it may be affected in up to 20% of these cases
The doctor should also check for any other injuries related to the fractured wrist. These associated injuries could include:
- Injury to the same-side elbow
- Injury to the same-side shoulder
- Damage to the joint connecting the two bones in the forearm
- Fracture of the bony bump on the forearm
- Damage to the cartilage disk and ligaments connecting wrist and hand bones
- Damage to other wrist ligaments
Testing for Wrist Fracture
Imaging is a crucial tool when it comes to assessing the seriousness of a fracture. It helps doctors understand how stable the fracture is and determine the best way to treat it. Plain x-rays should be taken both before and after setting the bone back into place if needed. The typical images taken include a front and side view of the wrist, plus an angled or ‘oblique’ view to give more detail about the fracture.
These additional angled images are especially helpful for looking at joint involvement, particularly for the ‘lunate fossa’ fragment, which is a part of the wrist. In some cases, doctors might take images of your other wrist to see what’s normal for you in terms of the ulnar variance and the scapholunate angle.
Sometimes, a computed tomography (CT) scan might be used to show how much a fracture involves a joint. Knowing the usual measurements on x-rays of the lower end of the radius (one of the bones in the forearm) can help doctors spot fractures in this area. These measurements can also help them decide on the best treatment.
A few of the key measurements doctors look at include:
- Radial inclination: Normally around 23 degrees.
- Radial height: Normally around 11 mm.
- Volar tilt: Normally around 11 degrees.
Treatment Options for Wrist Fracture
Breaking your wrist bone, or what doctors call a distal radius fracture, can be managed with either surgery or non-surgery. Non-surgical treatment is only possible if the bone break meets certain conditions like how much the broken bone has moved or its angle. If these conditions aren’t met, it’s recommended to consider surgery instead.
These are the criteria that a wrist fracture must meet for non-surgery:
* The difference or shortening in wrist height should be less than 5 mm.
* The change in the wrist’s inclination should be less than 5 degrees.
* The step-off, which is a change in surface level in the joint, should be less than 2 mm.
* The wrist’s tilt towards the dorsal side should be less than 5 degrees or within 20 degrees of the uninjured wrist.
If fractures have moved too far off from these conditions, a procedure called closed reduction is performed, which aims to put the fractured bone back into place. Adequate pain relief is provided during this procedure. Once done, the arm is secured in place with a big, special splint that restricts movement and provides room for swelling. Images of the fixed fracture are then taken to check if the bone is set at acceptable levels.
If the fracture meets these criteria, the patient will be sent home with the splint and asked to schedule regular check-ups. If not, surgery may be suggested. After the bone has been successfully set in place and doesn’t change, the splint can be replaced with a cast for six weeks.
Fractures where the broken bone hasn’t moved from its place are treated without surgery. They’re initially placed in a long-arm splint then later transitioned to a shorter cast for six weeks while the healing is monitored.
For fractures that have moved away from these ideal positions, it’s usually recommended to have surgical treatment. The aim of the surgery is to return the broken bone to the ideal position and secure it there to promote early movement. There are various ways the bone can be fixed, including using pins, external fixators, and plates. For fractures with a stable front bone layer, a pin is placed to keep the bone’s length and alignment. An external fixator is used together with a pin or a plate as it can’t securely restore the front bone layer by itself. It mainly relies on the stretching force of ligaments to maintain the position of the fractures. Normally, the external fixation lasts for eight weeks maximum, with aggressive hand therapy to maintain range of hand motion. A plate can also be placed inside the hand through a small opening to hold the broken bone together. It’s crucial to know that having a plate can result in irritation or breakage of both the flexing and extending tendons in the wrist.
What else can Wrist Fracture be?
X-rays can confirm the diagnosis, but there are several things that need to be taken into account:
- Other injuries that may be connected should always be considered
- The possibility of a fracture caused by disease
- Potential injuries to the carpus (the wrist bones)
It’s important for physicians to consider these factors to help make the most accurate diagnosis.
What to expect with Wrist Fracture
Open-reduction internal fixation and volar plating, surgical procedures, typically lead to good or excellent results in over 80% of patients. These results include improvements in movement range, strength, and general recovery outcomes. Studies comparing volar fixation with other fixture methods have shown equal or superior results.
Early recovery seems to be better with volar fixation, and the results are generally on par across all fixation methods. Some studies even suggest that volar plating may help maintain overall reduction better than other fixation types.
Possible Complications When Diagnosed with Wrist Fracture
Here are some potential complications related to certain medical conditions:
Median Nerve Neuropathy (Carpal Tunnel Syndrome):
- This is the most common neurological complication.
- It occurs in 1% to 12% of low-energy fractures, and up to 30% of high-energy fractures.
- A treatment for this condition is acute carpal tunnel release, which is typically used when there are progressively worsening symptoms of numbness or tingling, or weakness in moving the thumb. This treatment is especially considered if these symptoms do not improve after the fracture has been set back in place, or if the symptoms last for more than 24 to 48 hours.
Extensor Pollicus Longus Tendon Rupture:
- This complication has a higher occurrence rate with nondisplaced distal radius fractures, which are fractures of the radius bone close to the wrist.
Radiocarpal Arthrosis:
- This condition reportedly occurs in up to 30% of cases.
- Ninety percent of young adults may experience painful joint degeneration if there’s a misalignment of more than 1 to 2 mm in the joint surfaces.
- However, this condition might also be symptom-free.
- Other complications can involve the abnormal healing or non-healing of a fracture (malunion and nonunion).
Compartment Syndrome and Complex Regional Pain Syndrome:
- These syndromes are other potential complications.
Recovery from Wrist Fracture
The care after surgery for internal alignment and fixing with a volar plate requires an immediate volar splint. The patient should move their fingers actively and keep their wrist higher than their heart. This helps prevent stiffness and controls swelling. The splint gets removed after one or two weeks for the wound to be checked. A removable splint is needed and should be made by a hand therapist. It helps with swelling and must be worn all the time to protect the fixed fracture. The patient should not put weight on their upper limb but can start wrist movements after the first check-up after surgery. Between 4 to 6 weeks, they can start exercises like squeezing putty and gripping. After 6 to 8 weeks, the splint isn’t needed anymore, and they can start doing strengthening exercises. Normally, after 10 to 12 weeks, the patient can resume normal activities at a comfortable pace.
