top of page
Robot Hand

DYNAMO HAND Brace

Overview

How can a device restore mobility and independence for people with hand spasticity while remaining affordable and easily maintainable?

 

Goals

  1. I will use Solidworks and other 3D modeling software to design organic shapes and functional assemblies.

  2. I will work with multiple materials to design, develop, build, and test a physical product.

  3. I will be able to create products that can be replicated and reproduced for future adaptations and adjustments.

  4. I will discover new information about neurological conditions and their effects on the body.

 

Specifications

The final outcome of my project will be a device to help people with disabilities and low mobility in their hands. This will be a learning stretch for me as I have only worked with simple shapes in Solidworks, and I have never added other materials to my 3D prints. Learning to use other 3D software and making complex and functional shapes and assemblies will definitely be a challenge for me, and it will require my current skill set to grow massively.

Deliverables

Deliverable 1

I will turn in thorough research and an updated plan for my project.

​

Deliverable 2

I will submit sketches of my desired product to show a visual of my product. I will include labels and captions and begin listing my needed materials.

​

Deliverable 3

I will scan my hand and create a 3D representation in Solidworks so the device will fit to my measurements.

​

Deliverable 4

I will turn the mesh into a set of curves, lines, and dimensions using curve wizard that I can use as a reference.

​

Deliverable 5

I will build the base of the device that will connect the bottom of the finger pieces together- this will fit over the hand.

​

Deliverable 6

I will fine tune and rebuild parts that don’t function properly or aren’t to my standards aesthetically. I will create a second layer to hide all inner workings.

​

Deliverable 7

I will create a piece to fit over the wrist to support the joint. I will color and design details for functionality and aesthetics. I will lay out my parts in an assembly.

​

Deliverable 8

I will present and demonstrate my final product along with a document detailing my process.

​

​

Research

 

Problem

​

People with MS, Arthritis, Muscular Dystrophy, strokes, cerebral palsy, spinal injuries, and other neurological conditions (an estimated 12 million+) tend to have a common and debilitating side effect: clenched fists. These are caused by spasticity- an inhibition of motor neurons- not a muscle problem. When communication between the muscles and the brain is cut off, the muscles produce their own signals and stay flexed as a form of protection. The hand stays closed and often curls into the forearm. This prevents natural hand motions such as grasping and pinching, and can result in deterioration or shortening of the muscles. Treatments for this disorder are expensive and often ineffective.   

​

Rehabilitation Process

​

Typically, injuries and neurological disorders resulting in clenched fists can be helped. The best way to rehabilitate this symptom is through exercise. Repetitive motions can assist and rewiring the brain and regaining muscle tone. The most important thing in rehab is opening the hand and getting it out of that clenched and curled position, then encouraging opening and closing to regain strength. To address the root problem, brain-muscle communication must be restored. This can be done by using neuroplasticity, the rewiring of neurons in the brain, through very repetitive and controlled actions. There are typically three steps to recovering hand function after a central nervous system dysfunction- stretch open the hand with a splint, practice passive exercises (range of motion- someone or something stretching the joints to grow flexibility), then practice active exercises (using the muscles independently).

 

Current Treatments

​

Many different products have been created as assistance for people with disorders that may inhibit hand function. However, the majority of these devices either make objects easier to grasp or focus on attaching everyday objects to the forearm for easy use. Some involve stretching and bracing the hand over a flat area to prevent curling. This is an important step to prevent surgical intervention, facilitate improved functional use of the hand, and reduce the breakdown of skin. Other treatments, such as Botox injection, focus on relieving the symptom but not the cause, which isn’t sustainable. Other, more high tech models move the hand through electronics and signals. Electronic signals are also used to stimulate the nerves. More extreme cases are typically treated with incredibly invasive surgery. I would like to make a device that could restore motion to and help rehabilitate the hand so patients could eventually move their hands at their own free will.

​

Importance of Dynamic Splinting

​

Many splints used in spasticity treatment are incredibly similar- a curved or straight piece of plastic that holds the hand in place and prevents all movement, known as static splinting. This may seem like it would be beneficial in preventing further damage to the limb. However, long-term use of these devices can result in contracture- a loss of motion over time due to abnormal shortening of the soft tissue structures spanning one or more joints. These include skin, ligaments, tendon, muscles and joint capsules. This type of damage can make mobility loss much worse or even permanent. Dynamic splints allow the hand and fingers to stretch and flex freely while still keeping the hand out of a closed condition. This addition of motion allows for incredible benefits such as reduced joint pain, edema prevention, and nerve reconnection.

​

Requirements

​

  • The device must assist in restoring mobility and hand function (i.e. grasping, thumb opposition, pinching, etc.)

​

  • It must contain some type of material to pull the wrist and fingers out of a clenched position. This material must be strong enough to open the hand but be weak enough to allow movement back and forth.

​

  • The finger sections must be slip-proof for easy grasping of objects- silicon or rubber tracks or sleeves to aid grip.

​

  • The thumb segment must attach to the wrist, and the fingers must attach to the back of the hand to mimic their natural open stance.

​

  • It should be low-profile and lightweight.

​

  • It must be simple to use with little explanation.

​

  • The device should be pleasing to the eye and be customizable for patients who want a different look (i.e. children). Cables, springs, etc. shouldn’t be the main focal point.

​

  • It must consist of a low number of parts for ease of printing and assembling.

​

  • The finger segments must be jointed individual pieces that can convert between a rigid splint and a dynamic tool.

 

​

Materials NeedeD

​​

  • 3D-printed bases

​

  • Sugru silicone sculpted finger grips

​

  • Fishing line

​

  • Aluminum fishing line crimps

​

  • Jump rings

​

  • Elastic

​

  • 5/32” x 3-⅛” extension spring

​

​​

​

Sources

​​

​

​

​

​

​

​

​

© 2017 by Rachel Cox

R
bottom of page