What is Digit Amputation?
Finger amputation often occurs due to injuries, but can also happen as part of planned surgery for conditions like cancer, chronic conditions like Dupuytren’s contracture (a hand deformity), or peripheral vascular disease (circulation disorders that affect blood vessels outside of the heart and brain). It may also happen due to severe infections, though in these cases, the finger usually falls off on its own.
When an injury leads to finger amputation, the doctors primarily aim to save and reattach the affected finger to restore its function, especially if it is on the primary hand. However, this isn’t always possible due to several reasons like the time frame from the injury, how the injury occurred, and the level of contamination. When surgery is planned, deciding the level of amputation depends on factors like the need to clear cancer, alleviate symptoms, and maintain function. But for this explanation, we’re focusing on finger amputations due to injuries.
The main goal in treating finger amputations, especially involving the upper limb, is to:
- Maintain as much functional length of the finger as possible
- Ensure the remaining part of the finger is well-covered and protected
- Retain as much sensitivity in the finger as possible
- Prevent sensitive nerve endings (neuromas) that might cause pain
- Avoid a tightness or inability to straighten (contracture) in adjacent finger joints
- Help patients return to work quickly
- Fit a prosthetic finger soon, if required.
What Causes Digit Amputation?
When dealing with severe injuries, it’s crucial to follow a structured approach, like the advanced trauma life support method, which focuses on things like airway, breathing, and circulation. This helps check for any deadly injuries that need immediate attention before the patient with finger injuries is sent to a specialist for further treatment.
Understanding how the injury happened is also very important since it can influence the treatment plan and the patient’s recovery. For example, if the injury is sharp, it may clearly show where the amputation should take place. If the injury is blunt, it might be associated with injuries caused by crushing at the amputation spot. Lastly, avulsion injuries, which happen when a piece of tissue is torn away, could cause damage that isn’t as close to the visible injury.
Risk Factors and Frequency for Digit Amputation
Amputation injuries only make up about 1% of all trauma-related injuries that are treated in emergency departments. The most common types of these injuries are finger and thumb amputations. Most people experience this type of injury at home, not somewhere else. The majority of cases seen are fingertip or partial digit amputations, while full digit and multiple digit amputations are less frequent. Adults have a higher risk of such injuries, especially men who are four times more likely to have these injuries than women. Compared to children, adults are three times more likely to have amputation injuries. The most common cause of these injuries in adults is using power tools.
Signs and Symptoms of Digit Amputation
Understanding someone’s medical history is crucial, especially when it comes to amputations. Here are some important things to know: which hand the person typically uses (right or left), their job, when the injury occurred, what caused it, if other injuries happened at the same time, any pre-existing health conditions, and whether the person has eaten recently before an operation.
During the physical examination, the doctor will consider several factors, like the location and extent of the amputation, which body structures are involved, the health of the nerves and blood vessels, how the amputated part is functioning, and the extent of contamination (if relevant). The doctor will also evaluate the amputated part based on how the injury occurred (for example, a crush injury versus a clean cut) to decide if it can be reattached.
When dealing with finger amputations, they are usually classified according to the level of amputation. The Sebastian and Chung classification is generally used, and it breaks down amputations into different zones:
- Zone 1 distal amputations:
- Zone 1A – Beyond the lunula, through the sterile matrix
- Zone 1B – Between the lunula and nail bed
- Zone 1 proximal amputations:
- Zone 1C – Between the insertion point of the deep flexor muscle of the fingers and the neck of the middle bone of the finger
- Zone 1D – Between the neck of the middle finger bone and where the superficial flexor muscle of the fingers connects
Testing for Digit Amputation
If your doctor suspects that you may be experiencing blood loss, they might order a laboratory test called a CBC (complete blood count). This test assesses the different types of cells in your blood. If you are known to be taking blood-thinning medications, known as anticoagulants, your doctor may also order coagulation studies. These tests check how well your blood can form a clot, which is an essential part of the healing process.
Imaging tests can also be useful in the assessment of your condition. A type of X-ray, known as a plain radiograph, can be taken of the affected finger or hand, and of the part of the hand that has been amputated, if applicable. This X-ray allows your doctor to evaluate any injuries to the bone, assess the quality of the bone, and guide decisions regarding techniques to fix any injuries to the bone. Angiograms, which are tests that look at blood vessels, are not normally requested unless they are part of investigations for other injuries.
Treatment Options for Digit Amputation
If an individual suffers from a traumatic injury such as a partial or complete loss of a body part, it’s important to provide immediate medical attention. This involves taking steps such as administering first aid, preserving the removed part (if applicable), providing a tetanus vaccination, and delivering antibiotics following the guidelines a local hospital.
Those best suited to procedures where a severed body part is reattached are generally young, healthy individuals whose injuries were caused by precise methods that result in a clean amputation site and minimal damage to the surrounding tissue.
Reattachment may be considered for:
* Thumb amputations, since the thumb makes up 40% to 50% of hand functionality
* Multiple finger amputations
* Amputations at or closer to the palm
* Children with finger amputations at any level
* Single finger amputation past the point where the muscle that helps move the fingers (flexor digitorum superficialis) inserts itself
* Cases where the patient’s occupation or existing hand conditions require specialist care
However, reattachment may not be possible or recommended in certain cases such as damage to the muscles that bend the fingers (flexor tendons), smokers, severely crushed limbs, heavy contamination, improperly preserved amputated parts, injuries causing parts of the finger to be ripped off or yanked away (avulsion injuries), pre-existing surgeries to the affected finger, or if the person is mentally unstable or medically unfit.
In the operating room, the detached body part is assessed for its suitability to be reattached with emphasis on inspecting the nerve and blood vessel bundles. If these bundles aren’t in a condition suitable for reattachment, the procedure won’t proceed.
The reattachment process involves fixing the bone, repairing any tendon damage, rejoining the nerves, and reconnecting the blood vessels. The bone fixation is usually quick and dependent on the nature of the bony injury. If required, the bone may need to be shortened to allow the repair of other structures without stretching them too much.
If reattachment is not possible, and a decision is made to go ahead with amputation, an effort is made to create a functional, painless and mobile stump. Various techniques are applied to cover the stump, and the remaining bone should be smooth and free from bone chips. It’s also crucial to address the nerve at the stump end to decrease the chance of painful nerve growths (neuromas).
Maintaining the points where tendons attach can enhance the mobility and functionality of the stump. To prevent the tendons from sticking down (adhesions), the digit should be moved early on.
What else can Digit Amputation be?
While it usually seems clear when a finger or toe has been amputated, sometimes an infection can cause symptoms that make it look like there has been an amputation. It could lead to the loss of fingers or toes.
What to expect with Digit Amputation
Past research has shown a number of factors can greatly affect the outcome of a functional limb or finger after an operation. These factors include:
1. Where the amputation is on the limb
2. How many fingers were damaged
3. How and why the injury happened
4. The amount of time that passed since the injury occurred
Studies have shown that survival rates after re-attaching a limb or finger are between 80 to 90%. However, these numbers come from specialized healthcare centers.
It’s important to note that fixing the veins improves survival rates, no matter where the amputation is. This is key information because it’s not always possible to repair the veins. When this happens, it can cause a condition called venous congestion, where the blood flow back to the heart is blocked.
One way to solve this problem is by making a small cut near the end of the limb to allow blood to flow out. Alternatively, leeches can be used, as they can help blood flow by removing the blocked blood.
Possible Complications When Diagnosed with Digit Amputation
Complications that could occur after surgery can be divided into two types based on when they begin.
Early complications that might occur are:
- Arterial insufficiency: This typically comes as a pale, cool and pulseless digit. It’s important to keep a close eye on blood flow through the anastomoses (the surgical connection between two parts) after surgery to avoid blood clotting.
- Venous insufficiency: This usually appears as a purple digit with brisk capillary refill and swelling. If there’s worry about possible failure of the anastomoses or a blood clot, it should be checked out urgently. If there is venous congestion, leech therapy or anticoagulation may be considered to improve venous return.
- Infection
Late complications could include:
- Cold intolerance: The patient might become more sensitive to cold.
- Tendon adhesions: The tendons might stick together and restrict movement.
- Stiffness
- Bony malunion: The bone may heal in an incorrect alignment.
Another possible complication could be a change in feeling or sensation.
Recovery from Digit Amputation
After surgery, it’s important to stay well-hydrated and keep your blood volume stable. Pain relief will be provided, and you should keep your affected body part raised and warm. The reattached part of your body will be regularly checked to ensure the blood is flowing correctly, by observing its color and temperature.
For the first 48 to 72 hours, dressing changes should be avoided to minimize disturbance of the surgical repair. Depending on your case, blood-thinning medication might be considered.
In some situations where only the artery was reattached, a small cut might be made at the tip of the reattached part, then dressed with a special gauze soaked in a blood-thinning drug or leeches might be applied. This is all done to help blood flow out from the reattached part. Once your reattached part starts to turn back to its normal color, and the blood flow is as it should be, this treatment will be stopped.
Some patients might need to undergo additional surgeries to improve the function of their reattached part, like loosening of tendons, bone grafting or tendon transfer. Most people can return to work between 2 to 3 months after a surgery for an upper limb amputation. Studies have found that if your injury is closer to the hand, your function recovery, including movement and strength, is usually better than if your injury is further up the arm.
Preventing Digit Amputation
It’s crucial to have solid health and safety rules at the workplace. These measures help ensure a safe environment for employees and minimize the risk of work-related accidents. Similarly, spreading awareness among the public is another essential step towards ensuring safety. This is often done through information pamphlets or public awareness campaigns.
These campaigns aim to provide important safety information to the public, not just for workplaces, but for home environments as well. For instance, a news article by BBC in May 2018 was geared towards preventing accidents related to do-it-yourself projects and gardening. Such information helps people to stay safe during work and recreational activities at home.
