Upper extremity amputations and the options for prosthetic devices.
It is estimated approximately 45,000 digit amputations occur yearly in the United States. Partial hand amputations, referring to the partial or complete loss of one or more fingers or the hand, account for 90% of all traumatic amputations of the upper extremity (Munaretto, 2023). While amputations of digits, or fingers, may seem minor from the outside population, these amputations can lead to functional limitations, decreased quality of life, and disability. The most common cause of partial hand amputations is trauma related incidents. Most of the trauma injuries result from motor vehicle accidents, penetrating and blast injuries (military involvement, firework incidents, work accidents, etc.). Other causes include vascular compromise, malignancy, complications secondary to diabetes mellitus, and congenital abnormalities.
Regardless of the cause or level of amputation, there are numerous devices available with varying styles and functionality to help with your daily needs and activities. There are several types of partial hand prosthetics including body-powered, myoelectric, and hybrid prosthetics, as well as activity specific, passive or silicone based.
Body-Powered Partial Hand Prosthetics
Body-Powered partial hand prosthetics are durable and provide greater functional benefits compared to some other options. “One of the biggest functional benefits is that the force exerted by the prosthesis is directly controlled using a person’s wrist or the remaining portion of their hand, which makes movement and control feel very natural” (Finger, 2024). Some other benefits of body-powered partial hand prosthetics are they are low maintenance, restore digit length, lightweight, and waterproof to withstand different environments and activities. Some disadvantages include strength as the patient must have the strength and range of motion to work the device and cosmesis due to a more mechanical appearance.
Myoelectric Partial Hand Prosthetics
Myoelectric partial hand prosthetics have tiny motors inside each finger to create certain motions. Sensors or electrodes are placed on a remaining portion of the hand or wrist and detect movement of the muscles controlling the digit. The amount of strength the electric fingers exert is variable and controlled by the user depending on the given situation. Advantages of the myoelectric type includes helping the user achieve more natural hand movements, help patients generate more force and have greater pinch or grip strength, more intuitive control, can be operated in more planes of movement than body-powered systems, and a more cosmetic appearance. Some disadvantages include the devices are not always waterproof, the sensors need to be in direct contact with the skin and may not operate if the prosthesis is not on properly, batteries need to be charged daily, and it may require more training to operate.
Hybrid Partial Hand Prosthetics
Hybrid partial hand prosthetics are devices where two or three different types of prostheses are combined in one device. The prostheses can include a combination of passive, body-powered, electric and activity specific devices. For example, in a partial hand situation, the patient may need passive fingers with a body-powered thumb for better functionality or for better results for specific activities. These devices can be tricky to learn to operate different types of devices together, but with lots of practice and proper training, patient’s can have great success.
Passive Partial Hand Prosthetics
Passive partial hand prosthetics can help provide some function for everyday life, but do not have active grasp and release. Silicone restorations and positional digits can provide functional enhancement for a secure grasp. Depending on the patient’s preference, the prosthesis can be made with unique colors and designs or more lifelike to match a patient’s skin tone and provide a more cosmetic appearance. Silicone based prosthetics are stationary, but there are ‘ratcheting’ style fingers that patients can use their other hand or press the digit on something to place in a specific position.
Activity-Specific Hand Prosthetics
Activity-specific prosthetics are designed for work circumstances, sports, and hobbies depending on the patient's needs. Everyday prostheses with a standard terminal device are not always helpful when completing certain activities or tasks. These everyday prostheses can sometimes be damaged in certain environments which is where activity-specific devices can be extremely beneficial in reaching functional goals. Some examples of activity specific devices include cooking devices, weightlifting, sports, biking, fine wood working, hand and power tools, playing instruments, etc.
How do I find the right prosthetic device?
The extensive list of different types of partial hand prosthetics available can feel very overwhelming. There are numerous custom devices for different amputation levels offered by Naked Prosthetics, Point Designs, Partial Hand Solutions, Össur i-Digits, and other companies. If you are a recent partial hand amputee or are an amputee who’s facing challenges with their current prosthesis, contact our Tillges today to schedule a consultation with our upper extremity specialist to help find the right prosthetic option specific for your needs. Team Tillges is here to offer support, find the right solution and to help you reach your goals!
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