Stump Cone

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Stump Cone
BioEng 1161 Dept of Bioengineering University of
Pittsburgh April 18, 2005

• Marissa Ammer
• Jonisha Pollard
• Alison Saulsbery
• Mentor Bob Maguire
• DeLatorre Orthotics and Prosthetics, Inc.

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Amputation Procedure
www.wheelessonline.com
Sugarbaker, Bickels, Malawer Above-knee
Amputation www. Sarcoma.org
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Background

• Post-amputation dressings are applied to stump
  to
• Reduce edema (fluid collection)
• Prevent Thrombo (clotting) and embolic (occlusion
  of blood vessels) complications
• Stabilize stump shape
• Protect the stump from injury
• Three types of dressings soft, semi-rigid, rigid
• Soft dressings become a hassle, rigid dressings
  do not allow for wound cleaning or expansion
• Our device is semi-rigid

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Types of Dressings

• Soft Rigid Semi Rigid
• Ace bandage Cast
  Crash Helmet

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Competitive Analysis

• Soft dressings, Ace Bandages
• Rigid dressings, such as casts
• Weight bearing devices, such as FloTech
• Semi-rigid removable dressings, such as PSRRD,
  Crash Helmet

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Design Criteria

• The Stump Cone will use surgical spacer socks
  that can easily accommodate shape change
  throughout the day
• As the residual limb becomes smaller, the device
  will be able to fit around it maintaining
  compression
• The shell will be a harder plastic to protect the
  limb against bumps and falls

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Economic Consideration

• Hopefully covered by health insurance, but if not
  completely, still relatively inexpensive.
• Market Size 360 million in North America
• 3 million patients
• 1200 allowable charge for insurance (Anthem Blue
  Cross Blue Shield)
• Product will be distributed through hospitals and
  medical centers

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SolidWorks Modeling

• First designs in the planning stage

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Final Design
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Advantages of the New Design

• Shock protection
• Via Comcore patented composite material with
  excellent impact strength and fatigue life

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Advantages

• Fluid Drainage through drainage holes

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Advantages

• Adjustable
• clam shell
• Velcro strapping

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Advantages

• Pressure Relief
• Thermo plastic material
• Bottom opening

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Advantages

• Antibacterial Protection
• Charcoal padding- activated charcoal absorbs
  bacterial toxins and odor.

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Advantages

• Non-weight bearing
• Less bulk
• No buttock support
• More comfortable for user

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Advantages

• Best of both worlds
• Integrating features from soft and rigid dressings

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Methods to Test the Stump Cone

• Run an FEA in COSMOSWorks
• Survey prosthetists on what they think of the
  device

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Results of FEA Testing
50 lbs Normal Force Factor of Safety
4.2 (Design Check)
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Results from Testing

• Survey Results from Prosthetists
• Comfort Level 8
• Pressure 8
• Ease of Use 8.75
• Adjustability 7.25
• Protection 9.25
• On Scale of 1 to 10, where 10 is the best

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FDA Regulations

• Class I Device
• Permanent Device (greater than 30 days of use)
• Contact with the skin

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Acknowledgements

• Funding Contributions
• Drs. Hal Wrigley and Linda Baker
• The Bioengineering Department
• Donation of Materials from DeLatorre OP
• DeLatorre OP of Pittsburgh Personnel
• Brian the technician that made our prototype
• Drew Buffat, CP - Director of Prosthetics
• Bob Maguire, CP
• Jason, Head Prosthetic Technician
• Department of Bioengineering, University of
  Pittsburgh

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"...devices like those are the best for
treatment."
" Absolutely! It would shape the limb
wonderfully."