Single-Motor Myoelectric Hands

When choosing which terminal device will best fit one’s needs, wants and lifestyle, there are many factors to consider. Do you want something that can handle heavy-duty activities? Or is grasping objects quickly more what you are looking for? What do you want your device to resemble? Do you want a futuristic robot hand? Or do you want something that looks like a regular human hand?

Single-motor myoelectric hands can offer the benefit of looking very much like a sound hand while also being a device that’s controlled by one’s muscle signals. Passive silicone restorations can look very life-like, but they are passive, meaning, they have to be moved and manipulated by the user’s intact hand. Multi-articulating myoelectric hands can offer a variety of grips, but they look robotic. Single-motor hands can be covered with a custom realistic-looking glove so that most people don’t notice a limb difference.They also offer one or two muscle control spots which allow for the hand to open or close very quickly. Single-motor hands are the only myoelectric option available for children. It’s also worth noting that, generally, these types of myoelectric devices are more likely to be covered by insurance than multi-articulating myoelectric devices.

Our patient Sherri Whittiker uses the single-motor Variplus Speed hand from Otto Bock. At the beginning of Sherri’s video below, you can watch her make jewelry, holding the pliers steady with her prosthetic hand:

Our own Kristi Wolfgram, an Arm Dynamics team member, also uses the Variplus Speed hand. We asked her a few questions about her prosthesis, including why she chose this particular prosthesis: “My top two priorities when it comes to a prosthesis for daily use were durability and the ability to cover it with a custom silicone cover – and this one offered that.” We also wanted to know what kinds of tasks she found the prosthesis particularly helpful for: “It’s very helpful in holding objects to free up my right hand, so I can do things like open doors. I use it to hold the dog leash or hold a bottle of water. My daughter holds my prosthesis a lot when we’re walking together if I have something in my right hand.” While the grasping ability, speed, durability and silicone cover are what she loves about the device, she does sometimes wish the fine motor skills were a little more precise. “Tying little knots, threading a needle, arts and crafts with my daughter like latch hook — those are hard. I know from the experience I had with my body-powered device as a child that those types of prostheses are better for those little, fiddly tasks.” Regardless, the single-motor hand has more benefits for Kristi, so that’s what she’s been happily using for years.

While both Sherri and Kristi use the Variplus Speed hand from Otto Bock, there are other single-motor hands that can be covered, including the Motion Control hand from Fillauer, the Electrohand 2000 pediatric hand and the SensorHand Speed, both from Otto Bock.

Do you have any questions about single-motor hands? We would be happy to answer them. We offer complimentary consultations, either in person or via video chat, with our clinical team. Just contact us. Do you wear a single-motor hand or have experience with one and would like to tell your peers about your experience? Please comment below. Thanks for reading!

For more information, see related Arm Dynamics articles here:

• An Introduction to Passive Silicone Restorations
• Introduction to Multi-Articulating Myoelectric Hands
• Resources for Parents of Children with Upper Limb Differences or Limb Loss
• How to Stay Comfortable When Wearing an Upper Limb Prosthesis
• Introduction to Targeted Muscle Reinnervation (TMR)