Upper Limb Prosthetics
When considering upper limb prosthetics it is important to recognise that our natural upper extremities are highly complex in how they function. Prosthetic upper limbs cannot replicate these movement however thanks to advances in technology we are now able to fit prosthetic devices that are more intuitive, responsive, and functional. The aim however, whether we use the latest technology available or standard mechanical devices, remains the same; to aid the user to perform activities of daily living and leisure activities, and to improve body image and balance.
The reason for amputation and the level of amputation will influence prosthetic the type of prosthesis fitted and components selected. Our prosthetic team is available to assess your personal needs. Contact us for a free initial assessment.
Upper Limb Amputation Levels
Upper limb amputations can be divided into two broad categories – minor amputations and major amputations. Minor amputations generally refers to the amputation of digits e.g. fingers. Major amputations are commonly referred to as below elbow and above elbow.
- Amputation of the hand – there are numerous levels of hand amputation that range from amputation of the fingertip, to entire finger/s and partial hand.
- Through Wrist (also known as a wrist disarticulation amputation) – amputation through the wrist
- Below elbow (also known as a trans radial amputation) – amputation between the elbow and hand
- Through elbow (also known as an elbow disarticulation amputation) – amputation at the level of the elbow
- Above elbow (also known as a trans humeral amputation) – amputation between the elbow and shoulder
- Through Shoulder (also known as a shoulder disarticulation) – amputation through the shoulder joint. The scapula (shoulder blade) remains, and the clavicle (collar bone) may be removed
- Forequarter amputation – Amputation at the level of the shoulder in which both the shoulder blade and collar bone are removed
There are three types of upper limb prosthetics:
- Cosmetic – non functional
- Body Powered – functional mechanical devices that are powered with a shoulder harness
- Myo Electric – functional, controlled electronically. May also use a harness for the elbow joint. The elbow can also be electronically controlled.
The components that make up an Upper Limb Prosthesis
Hooks are terminal devices that are also classified as voluntary opening and closing and does not come with a cosmetic glove. Hooks were designed for users with more refined, but heavy duty goals like picking up smaller objects. (bolts and screws) These devices are more durable than anatomical-looking hands. Hooks are preferred by users that aren’t too fussed by cosmetics.
A voluntary opening hook will remain closed and will open when the user uses a shoulder shrug to put tension on the cable to open the hook and when the tension is release the hook will continue to grasp the object.
A voluntary closing hook will remain in an open position and will only grasp the object when the user uses a shoulder shrug movement to close the hook, the hook will only hold the grasp while the user has their shoulders flexed forward.
All prosthetic hands, except hooks, will be covered with a cosmetic glove that come in different shades and designs. The user’s prosthetist will use a colour chart to pick the correct glove for the user. There are different types of gloves but the most popular are usually the most anatomical design of glove.
Aesthetically, prosthetic hands usually replicate anatomical features and the functions mimic that of a human hand. These devices are attached to the prosthesis via a wrist unit.
In order to attach the hand to the forearm we use a wrist unit. There are different types on the market; basic wrist units are just to attach the hand thus there is no physical movement possible in the wrist- this results in the hand not being able to rotate. There are some which can be rotated by using the opposite limb, some that can be flexed and extended and even myoelectric-controlled wrist units that operate by means of muscle impulses.
When you are a below elbow (trans radial) amputee, or if you are amputated through the wrist or partially through the hand, you do not require a prosthetic forearm. For above the elbow amputees you would need a prosthetic forearm for aesthetics. The wrist unit is inserted into the distal end of the forearm and the hand is attached. The colour of the forearm can be changed by your prosthetist but there are gloves that covers the entire prosthesis to add to aesthetics.
The cosmetic glove does not interfere with the functioning of the prosthesis and only serve as protection of the devise and add to cosmetics. The gloves are selected based on your skin colour.
Through- and above the elbow amputees would require an elbow joint to enable them to flex and extend the elbow joint. Depending on the joint selected, the elbow joint can be free swinging or locked in different positions They usually allow for rotation to enable in- and external humeral rotation. Elbow joints are either manually powered or electronic.
As an above the elbow amputee, the prosthetic socket will make up for the space between distal/bottom end of the residual limb and the elbow joint. If you are a through shoulder (disarticulation) amputee, there are options for the prosthetist to either extend the socket to replicate an upper arm or use a prosthetic shoulder joint with exoskeletal spacers that is covered with cosmetic foam.
As with all prosthetic sockets, the fit is extremely important. An Upper Limb socket is custom made according to the shape and size of the residual limb. Your prosthetist will manufacture the socket once coning/shaping of the upper extremity is complete. An in-depth assessment is performed to determine the components used to ensure function of the prosthesis for the users daily tasks. The fitting process consists of casting, test fits, issuing of the prosthesis and follow ups. Different suspension options affect the design of your prosthetic socket and your prosthetist will discuss this before committing to the best option for you. Prosthetic sockets take some time to get used to. The residual limb will have volume loss- and gain and this is unfortunately a part of the prosthetic process- for all amputees- you will have tests fits to adjust your socket to fit as snug and comfortably as possible. During this process to ensure comfort, your prosthetist will work with you individually and with your therapist to make sure that the components work effectively and that you are taught how to use the prosthesis.
Prostheses description at different levels:
- Partial finger amputee (Phalangeal): The availability of Naked Prosthetics products in the South African market offers this level of amputee a highly functional prosthetic option, it is however costly. Non-functional silicon cosmetic prostheses are more commonly used. A finger cap or leather sleeve is also often used to protect the stump during work activities.
- Partial hand (Trans metacarpal) amputee: For those who would like to return to performing fine motor skills, there are products on the market that enables you, the user, to flex, extend and grasp the finger. These are customized exo-skeletal prosthetics that are light weight and easy to don, they are however costly. Non-functional silicon cosmetic prostheses are more commonly used for aesthetic purposes. A simple opposition device is an option in certain cases to allow for function during tasks. There are products on the market that enables you, the user, to flex, extend and grasp the finger. These are customized exo-skeletal prosthetics that are light weight and easy to don.
- Through Wrist (wrist disarticulation) amputee: When it comes to aesthetics this level of amputation is a little more of a challenge to conceal as there is componentry that needs to be incorporated into a limited space, creating a limb length discrepancy compared to the sound side. This level of amputation allows for either a cosmetic or Myo electronically operated prostheses.
- Below Elbow (Trans radial) amputee: This level of amputation will consist of a rigid prosthetic socket that attaches to either cosmetic, body powered or myo electronically operated prosthetic componentry. These include a hand and wrist unit.
- Through Elbow (elbow disarticulation) amputee: This prosthesis would consist of a prosthetic socket as well as an elbow joint and prosthetic forearm, the forearm is attached to the wrist unit and prosthetic hand. This can be operated by means of body power or myo electronics, or one could opt to fit a cosmetic prosthesis for aesthetics.
- Above Elbow (Trans humeral) amputee: This level of amputation consists of a prosthetic rigid socket, elbow joint, forearm, wrist unit and prosthetic hand. This can be operated by means of body power or myo electronics, or one could opt to fit a cosmetic prosthesis for aesthetics
- Through Shoulder (shoulder disarticulation) amputee: This level of amputation is fitted with a rigid prosthetic socket that would reach around the trunk, elbow unit, forearm, wrist unit and prosthetic hand. Options include cosmetic, body powered- very limiting- and myoelectronics.
- Forequarter amputee – This amputation level consists of a prosthetic socket that encapsulates the entire upper trunk on the amputated side and reaches across to the sound side, a shoulder, elbow, forearm, and wrist unit that fit onto a prosthetic unit.
Indications for prosthetic wear
- Would a prosthesis be of benefit allowing you to work more effectively and efficiently? job optimally?
- Would a prosthesis help you to perform activities of daily living?
- Would a prosthesis enable you to return to your sport or hobby of choice?
- Do you feel that a prosthesis would help you accept your amputation?
- Would using a prosthesis be of benefit to enhance your body image?
- Would you benefit from using a prosthesis to provide balance and even weight distribution, preventing spinal deformity especially in the higher-level amputations.
Contra-indications for prosthetic socket fitting
- Severe scar tissue
- Bony prominences
- Excessive soft tissue
- Hypersensitivity – extreme sensitivity to external conditions or in this case to touch
- Too short a residual limb (stump) to get prosthetic suspension
- Cognitive limitations
It is important to note that most contra-indications should be assessed on more than one occasion as situations and technologies change, enabling someone who may not have previously been a candidate to now be suitable for fitting with a prosthetic device.
The Look of the Prosthesis
|This is a passive device that can not open or close||This device is controlled by a harness and cable system that are powered by certain movements called “shoulder shrugs”||It is necessary for a certified Prosthetist to perform a physical assessment and MYO test on you to identify whether you have the muscle activity to operate a Myo electronic prosthesis|
|This provides aesthetic appeal, improving body image and body balance|
Shoulder shrugs will cause tension in the cable and result in the prosthetic hand to open or close
|Our muscles have the ability to generate a “signal” when flexing or extending and this particular signal is measured when performing the MYO test|
|You will still require a prosthetic socket||You get default set hands; either voluntary opening or closing|
Different muscle activities will be “allocated” to performing different tasks when operating the prosthesis
|A cosmetic glove is used to create a more aesthetic look||Voluntary opening: The hand remains closed and a shoulder shrug will open the hand|
Flexion of the stump might be “allocated” to closing the prosthetic hand, rotating the wrist unit and/ or bending the elbow joint
Extension of the stump might be “allocated” to opening the prosthetic hand, rotating the wrist and extending the elbow joint
|High definition silicone gloves are available for more lifelike look||Voluntary closing: The hand remains open and a shoulder shrug will close the hand||Myoelectric prostheses require charging: they have limited functioinal time before requiring re-charging|
|The prosthetist sets up the harness to get as much movement with as little effort as possible, as your physical ability increase the harness should be adjusted to lessen the strain on your musculature||The average time of use for a fully charged MYO prosthesis is 8-12 hours. We advice charging your device daily; like a cellphone|
|There are different types of hands, including hooks; these are to perform mechanical and finer motor movements||Warranties on high-end prosthetics should be discussed with your attending Prosthetist|
We often work with the following prosthetic suppliers in Upper Limb Prosthetics
- Otto Bock
This German company has a wide range of products ranging from cosmetic to muscle stimulus operated prosthetics. The latest product that was introduced into the industry is the MYOplus.
This device is the first of its kind; it enables you, the user, to operate your Myoelectric prosthesis by means of “pattern recognition”. This means that the componentry is activated by the stimulus the brain creates in the muscle by thought.
The company originated in Iceland and has been one of the market leaders in lower limb prosthetics. They bought upper limb prosthetic company Touch bionics and released a hand called the iLimb; This is a myoelectric hand that has been praised for its sleek design and user-friendly functions.
When Intefab collaborated with NAKED prosthetics we were delighted that their products became available in South Africa. NAKED prosthetics is a mechanical exoskeletal partial hand- and finger prosthesis that is custom made for each user.
If you are an active individual who wants to do MORE, then this company’s components are for you. They specialize in terminal device prosthetic components that allow the user to perform different types of sporting activities ie. Gym, cycling, motor cycling, skipping, catching a ball, rowing, archery, and many more
General care and advice (please confirm with your prosthetist)
- Avoid getting your prosthesis wet
- Avoid leaving your prosthesis in direct sunlight i.e. in the car or an exposed window
- Do not expose the glove to harmful chemicals. Certain glove’s nails can be painted with nail polish but the removal of the nail polish with products that contain acetone will void the warranty
- Replace axillary pads on your harness once every 6-8 months. Most harnesses come with spare pads
- Do not alter settings on your prosthesis unless indicated by your prosthetist
- Wash your prosthetic socket daily using a cloth, lukewarm water with body soap, gently wiping the socket clean
Frequently Asked Questions
We would not recommend swimming with your prosthesis as the exposure to water may negatively affect your components and void your warrantee.
Our natural upper extremities are extremely complex but following the loss of a limb the human body and individual often adapts very quickly with guidance from a rehabilitation specialist and is often able to perform all task with one hand. If the amputee is able to adapt to activities of daily living and feels like they do not need assistance to performing these tasks, the they do not have to have a prosthesis BUT this often involve compromise and a high level of compensation. The use of a prosthetic limb with rehabilitation training will be of benefit in performing daily tasks and leisure activities, assist in regaining confidence and improve body image and aid in restoring balance and trunk symmetry.
A Prosthesis’ weight is determined by the componentry used. Myoelectric prostheses would weigh more than a cosmetic prosthesis. The level of amputation, stump length and suspension method all impact the perceived weight of the prosthesis. A good fitting socket with good suspension is an essential requirement, more so than the actual weight of the prosthesis.
The price of any type of prosthesis is determined by the components selected based on the level of amputations and level of function. Contact us for an assessment and quotation for a prosthesis that meets your needs
Yes you can, if you have an adequately fitting socket with componentry that compliments your activities of daily living, it is advised that you wear your prosthesis as often as you can to benefit from the improved function and to maintain trunk symmetry .