Myoelectric Prosthetic Arms: How Assessment and Trial Fitting Work

How Muscle Signals Control the Prosthesis

When a muscle contracts, it produces a small electrical signal. Electrodes, which are sensors placed against the skin within the socket, detect that activity. A controller interprets the signal and tells a powered component to move. A battery supplies the power.

A common control approach uses selected muscle contractions to open and close a hand or operate another function. Some systems use pattern recognition: they learn patterns across several muscle signals and associate them with particular movements.

The control method and available movements depend on the system, the amputation level and the signals that can be used. A multi-grip hand, for example, offers different grip shapes, but that does not mean all movements happen automatically or without practice.

The term bionic arm is often used in marketing. It does not describe a single design, and a myoelectric arm does not reproduce every feature of a natural arm or hand. Ask what the proposed device can do and what you would need to control yourself.

Begin with Everyday Tasks

Start an assessment with real examples. Carrying shopping, holding a container while opening it, using a keyboard or handling a work tool may call for different functions. Explain which tasks you do frequently and where your current approach is difficult.

• Which tasks need a secure hold, a particular grip or support from both arms?
• Will you use the device indoors, outdoors, at work or around water?
• What matters most: appearance, weight, access to a task or speed of use?
• What do you already manage well with your current device or another method?

A prosthetist and occupational therapist can assess those goals together. They may consider a prosthesis, an attachment, an aid or a different way to do the task. Success is judged against the need being assessed, rather than how advanced the hand looks.

Bring items that represent your tasks if it is practical and safe. A short list is useful when the real equipment is too large to bring. Describe the load, surface and environment rather than relying on a product demonstration video.

Myoelectric, Body-Powered and Other Options

For some above-elbow fittings, a hybrid combines body-powered and electrically powered parts. Your team should explain which functions are controlled by each method.

No option is best for every person or every task. Weight, durability, feedback, appearance and ease of use can lead to different choices. A device for one activity may be useful alongside another approach for daily life.

What Assessment and a Trial Check

Assessment considers the residual limb, skin, joint movement, comfort, muscle signals and your ability to use the controls. The socket must hold the prosthesis securely and place sensors where they can detect the intended signals.

A trial may begin with practising control signals before a full device is fitted. It may then involve a trial socket or a demonstration component, depending on what is available and appropriate. Confirm the trial arrangements and any cost before starting.

Try relevant tasks, rather than judging only whether the hand opens and closes. Can you hold and release the object? Is control consistent when your arm changes position? Can you manage the weight and the time needed to select a grip?

Record what works, what is difficult and what still needs practice. Individual outcomes vary. A trial helps inform the decision; it is not a promise that a device will restore normal hand function.

Ask which systems the provider can assess or trial, what can be supplied, and what evidence would support a recommendation. Align’s upper-limb service includes myoelectric options. Specific models and trial access need to be confirmed with Maegan.

Training, Charging and Maintenance

Learning control is part of using the prosthesis. Occupational therapy may include practising muscle signals, selecting functions and using the device in daily tasks. The training plan should match the system and your goals.

Discuss how you will put the arm on, charge it, clean the interface and care for its parts. Ask about battery use, service arrangements and what to do if control becomes unreliable. Do not assume every myoelectric system tolerates water, dust or heavy manual work.

• Can I manage the socket and controls without help?
• When and how does this model need charging?
• Which environments and loads are permitted by its instructions?
• Who provides training, follow-up and repairs?
• How will I manage important tasks while it is being serviced?

A change in fit can affect sensor contact as well as comfort. Report skin problems or a change in control to the team. Adjusting the electronics alone may not address a socket or skin issue.

Funding and Preparing for Your Appointment

An assessment report and quote should explain the functional need, the proposed components, alternatives considered and any trial findings. Ask whether training, fitting, consumables and maintenance are included.

For eligible NDIS participants, funding decisions depend on the scheme’s criteria and assessed need. Being eligible for an assessment or finding a device useful does not automatically mean a particular system will be approved. Other funding arrangements have their own requirements.

Bring any current arm prosthesis, relevant medical reports and funding information. Wear clothing that allows the limb and socket to be assessed. Bring a list of your important tasks and the questions you want answered.

Ask what is achievable with the available options, what will need training, and what limitations remain. Read our prosthetic funding guide for payment questions and first appointment guide for the local process.

Align currently describes below-elbow and above-elbow services. Its service page says it does not currently make finger or partial-hand prostheses. Call to discuss a suitable referral if that is the service you need.

Frequently Asked Questions

Related Guides and Services

• Upper-limb prosthetics at Align
• When a socket needs review
• Repairs and replacement
• Prosthetic funding in Australia

Sources

Clinical guidance and manufacturer information checked on 10 October 2026. Your own fitting plan and the instructions for your device take priority.

• Ottobock Australia: upper-limb prosthetic options
• Ottobock: myoelectric control and powered hands
• Leeds Teaching Hospitals: multi-grip hand assessment and training
• NDIS: prosthetics and orthotics assistive technology assessment