For parents who are new to the subject of prostheses, or teens who are looking for more information, a terminal device is what replaces the hand at the end of the prosthesis. Like hands, terminal devices are used to interact with the people and things around you.
While there are more terminal device options for adults than for children, the ones that are available are helpful for younger patients who may have a congenital limb difference, such as symbrachydactyly, or who have partial hand or limb loss.
The age that a child can be fitted with a prosthesis depends on the level of their limb difference. We’ll start by talking about options for children that are missing a hand or more of an upper limb, and then address timing and options for kids with partial hand limb differences.
A passive prosthesis is what our clinical team generally recommends as the first prosthesis for a baby with a congenital upper limb difference. The terminal device does not have an active grasp but it helps the baby get used to wearing a prosthesis, bat at objects, and hold toys and other items by pressing them between the prosthesis and intact hand. We often suggest that an infant be fit at about six months since the prosthesis can help them with sitting balance, crawling and pulling up to standing. Our prosthetists can custom fit small, passive terminal devices that our young patients have found success with. TRS Prosthetics is one company that makes such devices.
At 18 months, we may recommend changing to a prosthesis that allows the child to open and close the device — a myoelectric prosthesis. They learn how to open and close the terminal device by contracting muscles in their residual limb. The muscle contractions produce electrical signals that are “read” by electrodes that are inside the prosthesis and touch the child’s skin. The signals are what move the terminal device and allow objects to be grasped, held and released. For toddlers and children, there is only one type of myoelectric terminal device available: single-motor hands. Otto Bock offers one of these types of hands, the Electrohand 2000. Adolescents have more options as they grow closer to being adult size. There are electric hooks in addition to single motor hand options, and more companies are now offering smaller sized, multi-articulating myoelectric hands for petite individuals that may also be a good size for teens.
Once a child is around three years old, body-powered devices may also be a great choice for kids that want to be able to get their prosthesis dirty or wet. A body-powered terminal device can be opened and closed by harnessing and moving a higher portion of the body. For example, if a child is missing their hand, a harness can be applied to the child’s shoulder(s) with a cable that connects to a body-powered hook or hand. When the child moves the shoulders or upper back, tension is applied on the cable, either opening or closing the device to grasp and release objects. TRS also offers child size body-powered prosthetic components.
Activity-specific devices are very helpful for kids who want to play sports or play a musical instrument. You can see our patient Amber Peterson with her two different activity-specific devices in the photo below.
Watch children use activity-specific, body-powered and myoelectric devices in the video below:
For children with a partial hand difference, either due to a "dactyly" condition, other congenital reasons or an injury, similar prosthetic options are available. However, it may be preferable to wait until their hand has grown enough to be an appropriate size for the applicable finger or partial hand components. We offer different, customized options based on the patient’s age, hand size, goals and amputation level. Check out Kimmie's video below to see what our team was able to create for her:
Are you ready to speak with our clinical team about what options are available for your child? Please contact us! Are you a teen who wears a prosthesis, or an adult who wore a prosthetic device as a child and would like to tell our readers about your experience? We’d love for you to leave a comment below. Thanks for reading!
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