Lifting Monster

BME 4013 BME Projects 1

Professor Nasir

By: Owen Cameron

Allaa Nori

Date: 12/17/15

Abstract Our project goal is to collaborate with University of Detroit Mercy in the guided efforts to

produce a tangible device design for a spinal cord injury patient. The need statement is as

follows: An ability to lift dog bowls without bending of the spinal cord to assist a patient who

suffers Cauda Equina Syndrome. The design concept is a lifting apparatus which lifts bowls to

patient’s waist and lowers bowls to ground. Introducing an accessible button controller so patient

can have direct device interaction. The novelty for our project to provide a cheap or cost efficient

approach to the design with long lifetime and minimal maintenance as an approach.

Introduction Background

We are involved in a collaborative effort between Lawrence Technological University and

University of Detroit Mercy. The collaboration has guided efforts to assist a patient who suffers

cauda equina syndrome. She suffers partial paraplegia, clotting disorder and obesity. The patient

has two dogs and bending causes her back pain. Currently, she is undergoing therapy to

strengthen both lower limb muscles. We are interested in a mechanical based sub-systems 1 & 2

to create final design based on a product defined for class 1 or 2 device for adaptability for the

patient with no clinical trial need. Will allow the patient to adhere to the product more effectively

aligned with time constraints for UDM and LTU. The details of the design concept discuss the

selected design for the project.

Problem Identification

The patient suffers from cauda equina syndrome causing her to be a partial paraplegic. Bending

causes back pain and she has two dogs that she cannot currently feed on her own. Our patient

experiences difficulties in bending and symptoms of cauda equina syndrome include:

● Low back pain;

● Pain in one or both legs that starts in the buttocks and travels down the back of the thighs;

● Bladder and bowel problems (inability or difficulty urinating, incontinence, constipation);

● Weakness in lower extremities and loss of sensations.

The patient wants to be able to feed her dogs but cannot due to the bending required and her

disease states prohibits bending.

Disease State Fundamentals

Anatomy and Pathophysiology

The patient is suffers from cauda equina syndrome causing her to be a partial paraplegic.

Bending causes back pain and she has two dogs that she cannot currently feed on her own.

Symptoms of cauda equina syndrome include:

● Low back pain;

● Pain in one or both legs that starts in the buttocks and travels down the back of the thighs;

● Bladder and bowel problems (inability or difficulty urinating, incontinence, constipation);

● Weakness in lower extremities and loss of sensations.

Cauda equina syndrome is an uncommon compression of the nerves at the end of the spinal cord

within the spinal canal. The syndrome can be caused by any condition that results in direct

irritation or pinching of the nerves at the end of the spinal cord. Also, she is undergoing therapy

to strengthen both lower limb muscles.

Focus is identified for spinal cord injuries in general as economic impact with costs do not

specify otherwise:

Normal anatomy and physiology

Anatomy –

The spinal cord is part of the central nervous system (CNS) protected by the vertebral column. It

extends from the brain to the lower border of the 1st lumbar vertebra being around the thickness

of the little finger (45cm-males and 43cm-females). The spinal cord gray matter is surrounded by

the white matter at its circumference. White matter ceases toward the end of the spinal cord

while the gray matter blends into a single mass forming what is called as the cauda equine.

Physiology –

The spinal cord consumes the 3 most important functions of an individual: sensation, autonomic

and motor control. The spinal cord contains the link between the brain and the rest of the body

where all impulses from the brain throughout the body and various organs is carried through the

nerve tissue in the spinal cord. The same concept applies when organs and tissues sensory nerves

pass information to the brain by travelling up to the brain through the spinal cord.

Nógrádi, Antal, and Gerta Vrbová. "Anatomy and Physiology of the Spinal Cord."

Transplantation of Neural Tissue into the Spinal Cord. Springer US, 2006. 1-23.

Description of disease function, causal factors, and disease progression

Paraplegic patient due to a spinal cord injury. Injury within the thoracic level or below in the

spinal cord; result in poor trunk control due to lack of abdominal muscle control. T-1 lower level

spinal cord injury with normal hand function, preform all motor f unction of non-injured person,

with the exception of standing and walking. Ability of walking for short distances using walker

or long leg braces. Pain associated with standing and walking.

“Spinal Injury Network Paraplegia (Paraplegia) <http://www.spinal-

injury.net/paraplegia.htm>”

Clinical Presentation, Outcomes and Epidemiology

Clinical presentation associated with this disease/condition (spinal cord injury):

Focusing on symptoms related to the vertebral column (most commonly pain) and any motor or

sensory deficits. Ascertaining the mechanism of injury is also important in identifying the

potential for spinal injury. The axial skeleton should be examined to identify and provide initial

treatment of potentially unstable spinal fractures from both a mechanical and a neurologic basis.

The posterior cervical spine and paraspinal tissues should be evaluated for pain, swelling,

bruising, or possible malalignment. Logrolling the patient to systematically examine each

spinous process of the entire axial skeleton from the occiput to the sacrum can help identify and

localize injury. The skeletal level of injury is the level of the greatest vertebral damage on

radiograph.

“Spinal Cord Injuries Clinical Presentation (Spinal Cord Injuries Clinical Presentation: History

and Physical Examination) <http://emedicine.medscape.com/article/793582-clinical>”

Assess clinical outcomes and Epidemiology:

Clinical outcomes –

Loss of ventilatory muscle function from denervation and/or associated chest wall injury; Lung

injury such as pneumothorax, hemothorax, or pulmonary contusion; Decreased central

ventilatory drive that is associated with head injury or exogenous effect of alcohol and drugs.

“Spinal Cord Injuries Clinical Presentation (Spinal Cord Injuries Clinical Presentation: History

and Physical Examination) <http://emedicine.medscape.com/article/793582-clinical>”

Epidemiology –

Studies suggest the incidence rate of SCI is about 40 cases per million population. With a United

States population of over 300 million persons, over 12,500 new cases occur each year. There are

between 240,000 and 337,000 persons living with SCI in the United States. The average age at

injury has increased from 29 years during 1970s to 42 years since 2010. There is an about 4 to 1

male to female ratio. Approximately 24% of spinal cord injuries occur among blacks, which is

higher than the proportion of blacks in the general population (12%). (NSCISC)

Morbidity, Mortality, Incidence, and Prevalence of this condition

Morbidity –

250,000 Americans are spinal cord injured. 52% of spinal cord injured individuals are considered

paraplegic. (NSCISC)

Mortality –

Life Expectancies for persons with SCI are still significantly below life expectancies for those

without SCI and have not improved since the 1980s. Mortality rates are significantly higher

during the first year after injury than during subsequent years, particularly for severely injured

person. (NSCISC)

Incidence –

40 cases per million population in the U.S. or approximately 12,500 new cases each year.

(NSCISC)

Prevalence –

The number of people in the U.S. who are alive in 2014 who have SCI has been estimated to be

approximately 276,000 persons, with a range from 240,000 to 337,000 persons. (NSCISC)

Evaluate the Economic Impact

Cauda equina syndrome is often concurrent with congenital or degenerative diseases and

represents a high cost of care to those admitted to the hospital for surgery. Hospital stays

generally last 4 to 5 days, and cost an average of $100,000 to $150,000.

Overall cost of the disease on society/healthcare‐system:

Paraplegia (AIS ABS)

- First year = $518,905

- Each subsequent year = $68,739. (NSCISC)

Below is a table listing all of the average yearly expenses and estimated lifetime costs based on

severity of injury (NSCISC):

“Spinal Cord Injury Facts & Statistics (Spinal Cord Injury Facts & Statistics) <http://www.sci-

info-pages.com/facts.html>"

Observations and Interviews

Both the LTU and UDM met with the patient one time as a team to observe and interview the

patient. She appears to have a very open living room space providing easy access for her

motorized cart that she rests on. There are two dogs that are in an open cage when entering the

living room from the front door. Also, there are a few hand rails bolted into the studs on the

walls when entering and leaving the living room to the back deck awning. She appears to need a

device to allow her to feed her dogs that she can easily interact with that won’t cause her to bend.

Current Treatment Options

Existing and emerging solutions for diagnosis, treating, and managing given disease state

Diagnosis –

Computerized tomography (CT) scan. A CT scan may provide a better look at abnormalities seen

on an X-ray. This scan uses computers to form a series of cross-sectional images that can define

bone, disk and other problems.

X-rays. Medical personnel typically order these tests on people who are suspected of having a

spinal cord injury after trauma. X-rays can reveal vertebral (spinal column) problems, tumors,

fractures or degenerative changes in the spine.

Magnetic resonance imaging (MRI). MRI uses a strong magnetic field and radio waves to

produce computer-generated images. This test is very helpful for looking at the spinal cord and

identifying herniated disks, blood clots or other masses that may be compressing the spinal cord.

“Spinal cord injury (Tests and diagnosis) <http://www.mayoclinic.org/diseases-

conditions/spinal-cord-injury/basics/tests-diagnosis/con-20023837>”

Treatment and Management –

Cauda equina syndrome is a medical emergency. Decompression surgery is required to relieve

the substance that is causing pressure/pinching with the nerves of the spinal cord. Early surgery

can prevent further nerve damage that may be irreversible. Long-term management includes pain

medicine, physical therapy, supportive braces, urinary catheters, and other treatments.

A spinal cord injury needs to be treated right away. The time between the injury and treatment

can affect the outcomes. Medicines called corticosteroids are sometimes used to reduce swelling

that may damage the spinal cord. If spinal cord pressure is caused by a growth that can be

removed or reduced before the spinal nerves are completely destroyed, paralysis may improve.

Surgery may be needed to:

- Realign the spinal bones (vertebrae)

- Remove fluid or tissue that presses on the spinal cord (decompression laminectomy)

- Remove bone fragments, disk fragments, or foreign objects

- Fuse broken spinal bones or place spinal braces

- Bedrest may be needed to allow the bones of the spine to heal.

- Spinal traction may be recommended. This can help keep the spine from moving. The skull

may be held in place with tongs. These are metal braces placed in the skull and attached to

weights or to a harness on the body (halo vest). You may need to wear the spine braces for many

months.

“New York Times (Health Guide) <http://www.nytimes.com/health/guides/disease/spinal-cord-

trauma/overview.html>"

Market Analysis

Current market landscape

With the current market the global patient handling equipment market is estimated to reach USD

19,684.9 million in 2019. According to Grand View Research, Inc. the market is expected to

grow at a CAGR 6.9% from 2013 to 2019. Our device classifies as a Medical Mobility Aids and

Ambulatory Devices described as “Transfer Lifts”.

"Elderly and Disabled Assistive Devices Market (Medical Mobility Aids and Ambulatory

Devices, Medical Furniture and Bathroom Safety Products, Hearing Aids and Vision & Reading

Aids) - Global Industry Analysis, Size, Share, Growth, Trends and Forecast, 2013." - Elderly and

Disabled Assistive Devices Industry Overview, Market Segmentation Report, Leaders, Future,

Demand, Opportunities, Sales, Company Profiles and Research Insights. Web. 17 Dec. 2015.

Describing market segments

The personal mobility devices market can be segmented into the following: Pre-hospital, In-

hospital and Post Hospital. The results are either distributed for the hospital or home health care

usage.

Pre hospital:

- EMS

In hospital:

- Inpatient care

Post hospital:

- Rehabilitation Centers

- In-home care

Defining market size, growth, and competitive dynamics of each segment:

Post hospital (Rehabilitation Centers)

Market size –

Projects are currently located in the following states: Alabama, Colorado, District of Columbia,

Georgia, Illinois, Massachusetts, Michigan, New Jersey, New York, Ohio, Pennsylvania, Texas,

and Washington.

Growth –

Model SCI Centers across the United States work together to demonstrate improved care,

maintain a national database, participate in independent and collaborative research, and provide

continuing education relating to spinal cord injury.

Competitive dynamics –

Between Rehabilitation centers - spinal cord injury accredited centers and non-accredited

centers.

“Rehabilitation Centers (Christopher & Dana Reeve Foundation)

<http://www.christopherreeve.org/site/c.mtKZKgMWKwG/b.4514607/k.681B/Rehabilitation_C

enters.htm#>"

Pre hospital (EMS), In hospital (In-home care) and Post hospital (In-home care)

Market size –

North America (U.S.), Europe (Germany, UK, France, Italy, Spain, Austria, Switzerland), Asia

Pacific (Japan)

Growth –

$12.373 billion in 2013 to $19.684 billion in 2019;

Forecasted to grow at CAGR of 6.2% from 2013 to 2019.

Competitive dynamics –

Developing technologically advanced personal mobility devices via extensive R&D investments

and entering into strategic alliances with buyers are some key sustainability strategies are

adopted by these market players.

Describing to what extent stakeholder needs are being met in each segment

Clinicians –

Evaluate and dictate on which methods to pursue for optimal care for patient where resources are

able to be pursued.

Hospitals –

Based on the injury type and required healing methods hospitals make revenue through

programs, directly from patient or through insurance means. Improvements in R&D along with

inside the hospital enhance quality of care.

Insurance companies –

Based on treatments available they either accept or deny coverage based on specified cost/benefit

ratio. Companies choose most optimal coverage based on cost/benefit ratio to align with overall

needs of the patient and which options for pursuance.

Rehabilitation centers –

After stabilization, the person with a spinal cord injury needs to go to a specialized hospital

called a rehabilitation center. National Institute on Disability and Rehabilitation Research

(NIDRR) funds 14 Model Spinal Cord Injury Facilities in the U.S.

Listing key considerations for choosing a target market

- Existing solutions available in market segment

- Insurance coverage in market segment

- Number of patients in market segment

- Cost/benefit ratio in market segment

- Availability of resources in market segment

- Adaptability for usage in market segment

Stakeholder Analysis

Influential stakeholders

i. First Responders (EMS/paramedics (minimize effects of any head or neck trauma), EMTs,

clinician engagement)

ii. Hospital - Personnel/Care

iii. Rehabilitation Centers

iv. Surgeons (Neurosurgeon, Orthopedic surgeon, etc.)

v. Physiatrist (physical medicine and rehabilitation)

vi. Care-giver

vii. Physiatrist for rehabilitation

Potential conflicts

i. Patients need improved devices and treatment but insurance companies will not pay for it.

ii. Limited accredited Rehabilitation centers for optimal treatment and care

iii. Limited resources with inpatient and outpatient care

iv. Limited coverage from insurance companies for personal mobility devices for outpatient care

Recognizing which stakeholders are the decision makers

i. Clinicians (decision makers who would determine the injury level by collecting diagnosis

data.)

ii. Hospitals

iii. Insurance companies

iv. Rehabilitation Centers

Mapping the current continuum of care

i. Hospitalization / Surgeon referral

ii. Spinal cord treatment

iii. Outpatient extended care (monitor injury with infection prevention)

iv. Rehabilitation Centers

v. Utilization of walker around home

vi. Care-giver to help with daily needs

vii. Motorized chair when leaving home

viii. Physiatrist for rehabilitation

Design Concept

Design Justification

We have decided on a concept for design based on our patient need. The patient specifically

requested a device capable of lifting and lowering 2 dog bowls containing water and food. Also,

the patient wanted the device to be controlled by clicking button in terms of operating. Another

request our patient had, is for the device to have an excellent life-time. From there, UDM and

LTU teams decided on having a mechanical structure with a lifting apparatus. What is

considered novel about the design application and cost efficiency. After discussion and research

from both teams we have come across the lifting method using a stepper motor. A stepper motor

can work effectively and accurately for short periods of daily operations. The stepper motors

have a wide range of properties such as torque, speed and accuracy suiting our design perfectly.

As stepper motors come in variety of properties other components such as linear slides and

couplers come in wide range of specifications to adapt almost all kinds of stepper motors.

Materials

Stepper Motor including power supply, driver and controller

Ball screw linear slide

Coupler

Cables

Button switches

Methods

LTU and UDM teams have developed precise methods which need to be done in order to

get the project completed as follows:

1. Design the mechanical structure of the body

This part of the project is purely UDM side of responsibilities, where UDM team designs the

mechanical structure that will have the lifting prototype attached to it. For this part, UDM team

will need to consider all parameters and aspects associated with the making of the structure in

terms of stability and center of mass. UDM team are expected to perform structural analysis

within the making of the structure. UDM team will be using Solidworks for modeling the

structure which will be also used for testing. Since Solidworks provides multiple mechanical

stimulation constructs the program can give data related to 3D models, structures and failure

concerns.

2. Design/purchase ball screw linear slide

This part of the project will be LTU team responsibility, where LTU team decide on the proper

ball screw linear slide for the prototype. UDM team are expected to provide LTU team with the

final dimensions of the mechanical structure, and LTU team will consider human interaction

phase with the prototype by designing the lifting design to reach its lowest point on the ground

and its highest point up to patient’s waist for the most convenient handling to improve the patient

life.

3. Purchase stepper motor + coupler

Once getting the first two methods done while deciding on the platform material and weight by

both teams LTU is expected to figure the proper motor to use. Deciding on the proper motor to

use for the prototype is going to be associated with many consideration. The main consideration

is the motor torque and speed. The relation between the motor torque and the motor speed

defines the capabilities of the motor in terms of accuracy and lifting abilities. Finally, choosing

the proper coupler that will be the attachment between the motor and the linear slide.

4. Compile the actuator

Compiling the actuator has to do with the 2nd and 3rd methods. Testing the actuator performance

will be the main concern within this part of the methods where we are aiming to have a prototype

that has an excellent lifetime. Therefore, our testing of the actuator performance will take into

account all failure concerns to make justification if needed.

5. Write Arduino code and implement to controller

Writing Arduino code that will be the communication between the controller (2 buttons) and the

actuator to set limits and proper operation of the actuator.

6. Test final prototype for final confirmation or changes

Finally, testing the final prototype by using multiple subjects with different weight and shapes on

the platform for a variety of ranges of time. The approach assures prototype effectiveness while

more importantly assuring safety concerns and failure possibilities for improvement and/or

changes. In addition, electrical components will be test for safety concerns in terms of heating

and human/animals interactions.

Project Relevance and Broader Impact

There is approximately 12,000 new cases of spinal cord injury per year. The number of people is

around 270,000 persons who have SCI in the United States alone as of 2012. Designing our

device will allow patients who have SCI to bend and feed their pets that would otherwise be too

difficult or impossible. Within the next 7 years there is going to be an increase from around 12

billion in revenue to 19 billion for the global elderly and assisted devices market. With the

increased revenue expectations the need for our design will increase as the market segment

expands.

Timeline and Project Schedule

Task Timeline

Design lifting prototype (choose proper

motor)

Jan 2016

Writing operating code Jan 2016

Design proper electrical setup Feb 2016

Design cooling-off system preventing heating

issues

Feb 2016

Design control system for prototype operation Feb 2016

Design/purchasing proper ball screw slide Feb 2016

Design/build the prototype’s mechanical body Feb 2016

Deadlines:

Finish all development and testing by March, 2016

Have a functional prototype by April, 2016

Budget

Cost (LTU)

Material Cost

Ball screw linear slide $200.00 + 54.00 shipping

Stepper motor including power supply, driver,

controller and cables

$135.00 + $58.00 shipping

Coupler $1.99

Cables $6.91

Button switches $14.79

Total $470.70 ± $150.00

Budget

Project budget is $1500 provided by UDM for this collaboration

References

1) “Elderly and Disabled Assistive Devices Market (Medical Mobility Aids and Ambulatory

Devices, Medical Furniture and Bathroom Safety Products, Hearing Aids and Vision & Reading

Aids) - Global Industry Analysis, Size, Share, Growth, Trends and Forecast, 2013." - Elderly and

Disabled Assistive Devices Industry Overview, Market Segmentation Report, Leaders, Future,

Demand, Opportunities, Sales, Company Profiles and Research Insights. Web. 17 Dec. 2015.

2) Nógrádi, Antal, and Gerta Vrbová. "Anatomy and Physiology of the Spinal Cord."

Transplantation of Neural Tissue into the Spinal Cord. Springer US, 2006. 1-23.

3) “Spinal Injury Network Paraplegia (Paraplegia) <http://www.spinal-

injury.net/paraplegia.htm>”

4) “Spinal Cord Injuries Clinical Presentation (Spinal Cord Injuries Clinical Presentation:

History and Physical Examination) <http://emedicine.medscape.com/article/793582-clinical>”

5) “Spinal Cord Injury Facts & Statistics (Spinal Cord Injury Facts & Statistics)

<http://www.sci-info-pages.com/facts.html>"

6) “Spinal cord injury (Tests and diagnosis) <http://www.mayoclinic.org/diseases-

conditions/spinal-cord-injury/basics/tests-diagnosis/con-20023837>”

7) “New York Times (Health Guide)<http://www.nytimes.com/health/guides/disease/spinal-

cord-trauma/overview.html>"

8) “Personal Mobility Devices Market Analysis By Product (Wheelchairs, Scooters, Walking

Aids, Canes, Crutches, Walkers, Premium Rollators, Low Cost Rollators) And Segment

Forecasts To 2020 (Personal Mobility Devices Market Analysis By Product And Segment

Forecasts To 2020) <http://www.grandviewresearch.com/industry-analysis/personal-mobility-

devices-market>"

9) “Rehabilitation Centers (Christopher & Dana Reeve Foundation)

<http://www.christopherreeve.org/site/c.mtKZKgMWKwG/b.4514607/k.681B/Rehabilitation_C

enters.htm#>"

9) “Elderly and Disabled Assistive Devices Market (Medical Mobility Aids and Ambulatory

Devices, Medical Furniture and Bathroom Safety Products, Hearing Aids and Vision & Reading

Aids) - Global Industry Analysis, Size, Share, Growth, Trends and Forecast, 2013." - Elderly and

Disabled Assistive Devices Industry Overview, Market Segmentation Report, Leaders, Future,

Demand, Opportunities, Sales, Company Profiles and Research Insights. Web. 17 Dec. 2015.”