Offloading Device for the Offloading Device for the Reduction of Foot Reduction of Foot Complications in Diabetic Complications in Diabetic PatientsPatients Michael OsborneMichael Osborne Rod AliabadiRod Aliabadi Patrick GonzalesPatrick Gonzales Colin SmithColin Smith Supported by:Supported by:

Dr. William Dougherty-AdvisorDr. William Dougherty-AdvisorRichard Brown-Certified Richard Brown-Certified PedorthistPedorthistDr. Kevin Robinson-Belmont Dr. Kevin Robinson-Belmont Univ. Gait LabUniv. Gait Lab

Diabetes and the Diabetes and the EffectsEffects Affects 20.8 Affects 20.8

million Americansmillion Americans Insufficient insulin Insufficient insulin

production or production or actionaction

NeuropathyNeuropathy Poor circulation Poor circulation Foot deformationFoot deformation Decreased healingDecreased healing

Deformations and Deformations and ComplicationsComplications

Charcot Foot Increased Pressure at Metatarsal Heads

Foot Drop Hammer Toe

“Within the rapidly growing diabetes market, companies will find it extremely challenging to protect their market share because of intensifying competition, no longer can a manufacturer concentrate on just one segment and lead the market. Apart from having an ambitious product line strategy, manufacturers need to enter into other diabetes segments in order to not only protect but also grow their market share.”

-Ajit Baid

July 2003

CEO, F&S industry analysis

Is There a Legit Is There a Legit Market?Market? $27,987 $27,987 20.8 million people20.8 million people 6% incidence6% incidence

= $34,927,776,000= $34,927,776,000

Orthotic Insert Orthotic Insert SpecificationsSpecifications

Inexpensive-Minimize Inexpensive-Minimize labor costs and cut costs labor costs and cut costs of customized insert by of customized insert by at least 50%at least 50%

Versatile-Manufacture it Versatile-Manufacture it to fit any standard extra to fit any standard extra depth shoe; built in depth shoe; built in modificationsmodifications

Preventative-Minimize Preventative-Minimize vertical plantar pressure vertical plantar pressure and incidence of wounds and incidence of wounds in the TYPICAL in the TYPICAL neuropathic patientneuropathic patient

Durability-Match the Durability-Match the standard useful life of standard useful life of four months for custom four months for custom insertsinserts

Current TechnologyCurrent Technology

Acor: QuickFit Pro and Acor: QuickFit Pro and QuickformablesQuickformables

Total contact and heat Total contact and heat formingforming

Require sizing (come in a Require sizing (come in a three size range) and three size range) and modification (at an extra modification (at an extra cost for materials AND cost for materials AND labor)labor)

Difficult to change after Difficult to change after initial fabricationinitial fabrication

Reduce fabrication time Reduce fabrication time and costand cost

Inadequate durability and Inadequate durability and performance compared to performance compared to custom insertscustom inserts

Proposed ProductProposed Product

Manufactured, four-layered, Manufactured, four-layered, modifiable orthotic insert for modifiable orthotic insert for the general diabetic patient the general diabetic patient with neuropathy and foot with neuropathy and foot deformationdeformation– all sizesall sizes– Perforated from the Perforated from the

bottom up to quickly bottom up to quickly offload areas of high offload areas of high pressurepressure

– Removed sections of Removed sections of cork can be reattached cork can be reattached to previous location or to previous location or can be used to build up can be used to build up another areaanother area

– Head-molding Head-molding capabilities make the capabilities make the insert total contactinsert total contact

Costs and SafetyCosts and Safety

Proposed Cost: $40/pair; compare to current $260/pair Proposed Cost: $40/pair; compare to current $260/pair for custom and $25/pair for Acor Quikfitfor custom and $25/pair for Acor Quikfit

Proposed Budget: $300 due to F Scan sensor and Proposed Budget: $300 due to F Scan sensor and materialsmaterials

Safety:Safety:Foam bottoming out-test to determine useful life and Foam bottoming out-test to determine useful life and

provide warningsprovide warningsUser modification-warnings and educationUser modification-warnings and educationImproper modification by provider-sell only to licensed Improper modification by provider-sell only to licensed

physicians and pedorthistsphysicians and pedorthists

FDA Class I Device: no 501(k) necessary, must submit FDA Class I Device: no 501(k) necessary, must submit Good Manufacturing PracticesGood Manufacturing Practices

F-scanF-scan

Provides bipedal Provides bipedal plantar pressure and plantar pressure and force measurements on force measurements on the feet using paper-the feet using paper-thin reusable sensors thin reusable sensors placed in shoes.placed in shoes.

The actual sensor is a The actual sensor is a resistive sensor with a resistive sensor with a resolution of 0.25 cmresolution of 0.25 cm22

This is a key factor in This is a key factor in quantifying the results quantifying the results of the pressure of the pressure offloading of our insert.offloading of our insert.

www.tekscan.com

MaterialsMaterials

Material

Heat Formable Temperature

(F)Durometer

(Shore)

Minimum Thickness Available Additional Benefits

P-Cell 250-275 20-25 1/16" Top layer, serves to control friction

Plastazote 250-285 20 1/16"

Puff Lite 250 25 1/8"

BirkoCork 325 - 5 mm stability and durability

Cushion Cork - - 1/16"

Multi-Cork 300-325 50-63 1/8"

NORA EVA - 18 1.5 mm

SPENCO - 40 1/16" shock absorption, shear force maintenance

MicroCell Puff 275-300 35 1/16"

Poron 14-55 1/16" pure shock absorbance

Material Material ExperimentationExperimentation

Compare and contrast vertical Compare and contrast vertical plantar pressure plantar pressure measurements (pressure vs. measurements (pressure vs. time) during normal gaittime) during normal gait

Compare five inserts to Compare five inserts to determine if fourth layer is determine if fourth layer is necessary and which material necessary and which material is most easily perforated and is most easily perforated and provides the best offloadingprovides the best offloading

Pressure conversion factor Pressure conversion factor given as one unit to 1.4 psigiven as one unit to 1.4 psi

White Plastizote base offloads White Plastizote base offloads the most, but cork is almost as the most, but cork is almost as good and MUCH easier to good and MUCH easier to perforateperforate

Blue Line: New Balance InsertBlue Line: New Balance InsertGreen Line: White Plastizote and SpencoGreen Line: White Plastizote and SpencoPink Line: Cork and Diabetic Tri-lamPink Line: Cork and Diabetic Tri-lamBlack Line: P-Lite and Diabetic Tri-lamBlack Line: P-Lite and Diabetic Tri-lamRed Line: White Plastizote and Diabetic Tri-Red Line: White Plastizote and Diabetic Tri-

lamlam

Time (ms)

Vertical

Plantar

Pressure

Shape of PerforationShape of Perforation

Test perforation schemes Test perforation schemes with static tests on loaded with static tests on loaded first metatarsal head on first metatarsal head on diabetic tri-lam (1/8 inch diabetic tri-lam (1/8 inch layers) with no base layerlayers) with no base layer

Dual layer perforation Dual layer perforation shown to be best-base layer shown to be best-base layer and Puffand Puff

Pressure conversion is one Pressure conversion is one unit to 1.4 psiunit to 1.4 psi

Red line: Diamond perforationsRed line: Diamond perforationsBlue line: Circular perforationsBlue line: Circular perforationsBlack line: Diamond perforations below circular Black line: Diamond perforations below circular

perforationsperforations

In order to fit into standard In order to fit into standard extra-depth shoe, we will extra-depth shoe, we will use 1/8” of Pink Plastizote use 1/8” of Pink Plastizote and Poron on top of 1/16” and Poron on top of 1/16” Puff with a standard shaped Puff with a standard shaped cork basecork base

Time (ms)

Vertical

Plantar

Pressure

ConclusionsConclusions

There is a rapidly increasing market for diabetic There is a rapidly increasing market for diabetic footwear.footwear.– Many patients cannot afford necessary footwear.Many patients cannot afford necessary footwear.

The current process of orthotic customization is labor The current process of orthotic customization is labor intensive, expensive, and unavailable to rural patients.intensive, expensive, and unavailable to rural patients.– The cost and availability can be optimized by The cost and availability can be optimized by

minimizing labor.minimizing labor. The use of surface depressions is a common method of The use of surface depressions is a common method of

offloading used in industry.offloading used in industry.– Perforations address this need and allow Perforations address this need and allow

modifications.modifications. Recommendation: Project can be continued to develop Recommendation: Project can be continued to develop

a “smart” insert that records pressures during the day a “smart” insert that records pressures during the day and alerts patients of potentially dangerous plantar and alerts patients of potentially dangerous plantar pressures.pressures.