Assitive TechnologiesID 20123/26/2013Kaj Niegmann

What is life like with only one leg?

He used to be an avid motorcycle rider and adventurer. At 21 years old he has his entire life in front of him and he doesnt want anything to hold him back.

Three weeks ago John was hit by a car while riding his motorcycle to work in Atlanta. His left leg was crushed between the motorcycle and the car. The doctors were forced to amputate his left leg right above his knee to save Jack from a life of pain. The driver was uninsured and Jacks insurance barely covered his intitial medical bills.

After the surgery Jack developed a severe amount of scar tissue that prevented him from getting a prosthetic. He would require another surgery to remove the scar tissue but he lacked the funds. Since a prosthetic leg wasnt possible, Jack had to rely alternate meas of mobility.

He uses his axillary (underarm) crutches most of the time while commuting around his college campus. Every once in awhile he uses a wheel chair if he knows he will be out and about for a long time.

Meet Jack.

Client: Trans-femoral amputee (above knee amputation)

Situation: Client, 21 year old male, suffered lower leg injury from a motorcycle accident. Post surgery a large amount of scar tissue eliminated the possibility of using prosthesis. The client has been using crutches for 6 months since his accident. The client uses all of the same accessories that he had before his accident. He does not want to purchase assistive devices that are not 100% necessary (i.e. crutches). He wants to continue doing his daily living activities the same as before his accident to retain a sense of normalcy. The client uses underarm crutches he had from a previous accident and cannot afford forearm crutches and does not want the limitations created by a wheelchair, power chair, or leg scooter. Mobility: Travels using under-arm crutches Accessories: Clothes, belt, two strap backpack, keys, wallet, phone, purchases User Needs: The user needs to get inside of buildings. The user needs to carry a backpack. The user needs to ride the trolley. The user needs to get to the second floor of Barnes and Nobles. The user needs to pay the cashier.

Simulation: Simulating the client revealed many problems. The client completed all of the necessary tasks; how-ever, he stumbled multiple times, started to fall while exiting the trolley, fell against a wall due to backpack catching a crutch, had trouble managing his purchases and money all at once, crutches separated while try-ing to use them as one, and had trouble navigating narrow parts of Barnes and Noble.

Problems: Crutches snagging backpack strap causing client to stumble or fall Entering/exiting the trolley safely Separating crutches Handling purchases while operating crutches Navigating tight spaces

Specific Issue: Decrease the chances of crutches snagging the clients current backpack. Byfindingasolutionhewillbeabletowalksafer.

Needs: The client needs his backpack straps out of the way of his crutches. The client needs to take his backpack off easily The client needs a comfortable crutch experience Theclientneedsconfidenceinwalking Specifications: Fits into the users daily life without drawing attention or distraction Stored somewhere so user does not have to carry it separetely Affordable Augments a current accessory The solution must work with his current lifestyle/accessories.

SometimesMost Often Not Applicable

Mobility

Simulation

To better understand and empathize with Jack, I set up a simulation where I would experiencefirsthandthedifficultieshefaceseveryday.

These were the three main problems discoved during the initial user simulation. They directly impact Jacks solution to mobility and pose hazards to him. I chose to explore a design solution to his crutches catching onto his backpacks straps. This decision was based off the fact that I may be able to remedy crutch slippage and loss of balance problems by solving the straps catching problem. These problems were chosen as most important because they connect needs that are big enough to be profound to related ones that are small enough to solve.

Crutch Slippage

While perfoming the simulation one of the most notable problems was the crutch slipping out of position while the user moved quickly. This may have been a user-specific problem but it was a problem none-the-less.

Catching Straps

The most severe and potentially dangerous problem discovered during the simulation was the users crutch catching on the users backpack strap. This caused the user to start to fall of the bus while exiting. Also this loosened the backpack straps over time and the user had to re-adjust before entering the bookstore.

Loss of Balance

Walking with crutches and a backpack while having one operational leg created many opportunties for losing balance. Loss of balance for a person with one leg poses safety issues and falling can lead to serious injury.

Design Opportunities

Identitfying the Problem

Proper use of axillary crutches, as prescriped by a Doctor and Physical Therapist, is to place the tops 1.5 inches below the armpit and press against the ribcage for support. The users elbows should be slightly bent while holding the grips which should be adjusted to the hip line.

If a user is to wear a backpack properly, tight agianst the body with the weight above the hip line, the backpack straps and tops of the crutches conflict with one another.

While walking the crutches press against the ribcage and straps which causes discomfort. Occasionally the straps get caught around the tops of the crutches which can cause the user to stumble, lose balance, or fall.

Bag Crutch Bodyoror

After researching and identifying the problem, I had to decide which entity of the problem could be altered so that a solution could be achieved.

Since I could not alter my users body, and I did not want tosacrificetheintegrityofthecrutch as a mobility device, the obvious path to take was to alter thebackpacktobetterfittheuserwhile using crutches.

A quick whiteboard session let me distill the problem in simple diagrams. How can I separate the crutches from the backpack straps?

I took note of common features inbackpackstotrytofindacommon unit so that I could design a more universal solution.

Cargo and camping backpacks have webbing sewn all the way up the straps to add extra strength and attachment points.

Laptop and light travel backpacks lack padding and straps supported by extra webbing.

Three quarter inch webbing is the common denominator.

My focus was to create a simple device that attached to the common three quarter inch webbing pulling the straps away from the side of the ribcage and crutch tops.

Thesquareconceptwaschosenforitspuresimplicity.Itfitsnugglyaround the webbing and blended in with the user. However, It caused the straps to tighten down even when the strap adjustments were fully let out. It was also diffeicult to insert the straps into the prototype be-cause of how small it was.

Since the prototypes did not work well, I had to take a step back and rethink ways to augment the backpacks straps away from the crutches.

I took inspiration from hiking backpacks. They have an aftermarket sternum strap that is available for purchase that clips directly onto the support webbing that runs up the strap. Since travel/laptop backpacks do not have this webbing,

I centered my new focus on creating an adjustable sternum strap for backpacks without any traditional accessory attachment locations.

After my second phase of sketching I settled on the sternum strap I was going to pursue. It featured a center release button for easy removal and minimalistic clips that will attach to the users backpack straps.

I prototyped this version as well as two other straps just to be sure that this was the right decision.

Soft AttachmentUsing 3/4 inch webbing as the attachment device did not prove to be very successful. The soft webbing did not offer any support to the flimsy foam backpack strap and it pinched in on itself which caused discomfort for the user.

Side-Release BuckleThe side-release buckle offers adjustment on one side of the strap so the user can set their comfort level. It is a successful and affordable attachment system, however, it requires more finitedexteritytoreleasethebuckle.

Center-Release Buckle

This custom designed center-release buckle allows the user to very easily release themselves from the sternum strap. They have a choiceofusingfinitedexterity to push and slide to release or to stretch the strap and givethelargebuttonafirmtaptorelease.

The soft strap prototype failed in creating a comfortable wearing experience.Theonlybenefittothisversion is extremely low cost to manufacture.

The side-release buckle prototype was successful in relocating the backpack straps. During another test simulation it was much easier to walk with crutches without worrying about snagging a backpack strap.

Thefinaldesignisasternumstrapthat pulls the clients backpack straps in towards the chest. This frees up the ribcage area for uninterupted axillary crutch use. A custom center release buckle allows for easy buckling and one touch unbuckling. The strap clips can be slipped onto most laptop backpack strap and squeeze the padding for a tight fit. They can be slid up and down the backpack strap for further adjustment and comfort. The product blends in with current backpack materials and does not stand out giving the user relief without attracting attention.

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