Introduction to i-Digits


i-Digits is a multi-articulating myoelectric partial hand prosthesis for individuals with absence of 1 to 5 digits.

i-Digits is created from a kit of components, built into a custom socket to fit the individuals residual limb, with a self contained wristband housing batteries and a microprocessor. The digits can be individually positioned for customisation to the individual's presentation.

i-Digits is not intended to be a cosmetic restoration, instead it focuses on functionality for the user.

i-Digits is a functional prosthesis, replicating the features of a natural hand

Conformable grip:
shapes around
objects​

Manual
thumb rotation:

to achieve a range
of grip positions​

Integrated:

works in
conjunction with any
remaining digits​

Automated grips:
such as pinch and
lateral, for increased precision
in completing tasks​

Multiple control
options:
for optimal grip access

Personalisation: create a prosthesis specific to each
individuals functional needs

i-Digits Introduction

User Benefits


i-Digits has a wide range of features designed to benefit the user in their day to day activities.

Feature
User Benefit

Works in conjunction with remaining digits
Digits are positioned to function alongside any anatomical digits

The residual function of the hand is utilised with the i-Digits to maximise user functionality

Conformable digits
The digits shape around the object being held

Provides a secure grip on the object and provides a natural grip appearance

Manual thumb rotation
Position thumb manually throughout range from lateral to opposition

Allows a range of grip positions to be achieved for optimum grasp on objects

Automated Grips
A wide selection of grips to choose from where only specific digits are active

The user can select the grips which are most relevant to their lifestyle, allowing increased precision within those tasks

Control Options
Multiple control options available to access automated grips

The user can choose the methods which best suit them, allowing personalisation of the prosthesis to an individual's needs

Gesture Control
A method of accessing automated grips through movement of the i-Digits Quantum

Enables access to 4 grips via one easy to learn control method

Vari-Grip¹
Increased grip force when required

The appropriate amount of force for the current task can be applied

App
Mobile Apps for clinician and user

The user can personalise the i-Digits to their needs and has control of some features. The myo-graph allows ongoing training of muscle signals

Feature
User Benefit

Works in conjunction with remaining digits
Digits are positioned to function alongside any anatomical digits

The residual function of the hand is utilised with the i-Digits to maximise user functionality

Conformable digits
The digits shape around the object being held

Provides a secure grip on the object and provides a natural grip appearance

Manual thumb rotation
Position thumb manually throughout range from lateral to opposition

Allows a range of grip positions to be achieved for optimum grasp on objects

Automated Grips
A wide selection of grips to choose from where only specific digits are active

The user can select the grips which are most relevant to their lifestyle, allowing increased precision within those tasks

Control Options
Multiple control options available to access automated grips

The user can choose the methods which best suit them, allowing personalisation of the prosthesis to an individual's needs

Gesture Control
A method of accessing automated grips through movement of the i-Digits Quantum

Enables access to 4 grips via one easy to learn control method

Vari-Grip¹
Increased grip force when required

The appropriate amount of force for the current task can be applied

App
Mobile Apps for clinician and user

The user can personalise the i-Digits to their needs and has control of some features. The myo-graph allows ongoing training of muscle signals

¹ Not on i-Digits Access

i-Digits Introduction

User Selection


Suitable Candidates

i-Digits is for individuals with 1 to 5 digit partial hand absence which is: Distal to the wrist AND proximal of the metacarpal-phalangeal joint.

It is designed for low to moderate weight bearing everyday activities.

i-Digits will restore a gross grasp to the hand in most cases - restoration of fine grasp will be dependent upon the physical presentation e.g. if the thumb and index finger are intact then restoration of fine pinch is not required.

The users priority must be for functional gain, as i-Digits is not offered as a cosmetic solution.

User Evaluation

A complete evaluation should be carried out of all potential user's, with particular attention to

  • Skin condition: healing, scaring, sensitivity
  • Strength and range of movement in any remaining fingers
  • Strength and range of movement of the wrist
  • Shape of residual limb to facilitate suspension
  • Control site possibilities
  • Condition of contra-lateral hand/arm

The extent of functional impairment within the hand should be identified, alongside evaluation of how the individual currently completes daily activities.

To achieve optimum outcomes with the i-Digits prosthesis, individuals should

  • Be motivated to use a prosthesis
  • Have clear and realistic functional goals
  • Have an understanding of the time, effort and patience involved in learning to use the prosthesis
  • Be aware that i-Digits will not match the appearance of their sound hand
  • Understand that i-Digits is not a replacement for a human hand, but a tool to assist with functional tasks

Occupational Therapy Training

The Occupational Therapist is a key member of the upper limb multi-disciplinary team. They are responsible for maintaining focus on functional goals and supporting the user on the best ways to incorporate their prosthesis into their day to day life.

Therapy training is person centric, focusing on personal goals, lifestyle and interests.

Optimum user outcomes are achieved when the Prosthetist and Therapist work closely together with the user.

Studies support the inclusion of Occupational Therapy in upper limb prosthetic fitting.

  • Early therapy nearly doubles the rate of daily use. Fletchall, S. “Returning upper-extremity amputees to work”. The O&P Edge. 2005; 4:28-33.
  • Research suggests skilled, individualised therapy with the prosthesis takes an average of 20-30 hours. Resnik, L. Meucci, MR, Lieberman-Klinger, S, Fantini, C, Kelty, DL, Disla,R, Sasson, N. “Advanced upper limb prosthetic devices: Implications for upper limb prosthetic rehabilitation.” Arch Phys Med Rehabil. 2012; 93: 710-717.

i-Digits Introduction

i-Digits Design


i-Digits prosthesis is designed specifically to the individual user's presentation and requirements. There are many options available in relation to design including materials, trimlines and suspension.

Materials

The inner socket is manufactured from medical grade silicone:

  • Allows shaping to the contours of the partial hand
  • Accommodates the i-Digits signal inputs

The outer socket is typically laminate resin:

  • Provides secure attachment for the mounting plate
  • Lightweight
  • Shapes well to contours of silicone socket and i-Digits components

Note: Carbon fibre is not recommended due to interference properties with electrodes.

Trim-Lines

The trim-lines of the socket can be located:

  • At the wrist
  • Just proximal to the wrist
  • Mid/proximal forearm

Socket trim-lines are determined based on:

  • Remaining anatomy
  • Suspension requirements
  • Control site location
  • Range of motion available

Suspension

A secure fitting socket is required to give the user security in completing tasks and also to maintain consistent contact with the electrodes / FSRs. The shape of the residual limb determines the suspension possibilities. Options include:

  • Zipper incorporated into the silicone socket
  • Strap (hook & loop, buckle, ratchet) attached to inner or outer socket
  • Push fit / anatomical suspension

i-Digits Introduction

i-Digits Kit


i-Digits is supplied as a kit comprising of a selection of individual components which are assembled to the custom fabricated socket to create a unique i-Digits prosthesis for the individual user.