PROCESS OF MANUFACTURE OF CUSTOMIZED SPLIT INSOLE FOR DIABETIC PATIENTS

Abstract

Under the inventive process, the customised split insole is made by processing manually collected medical data and arch data along with plantar pressure distribution data and foot type data both of which are collected using a computer enabled Plantar Pressure Measuring Device in a first computer and processing these data in a second computer to generate a Projection Data which is expressed in Shore Hardness Value. Then, ranking of the projection data into a zone wise Ranking Index, determining the elasticity of the material to be used for the said Shore Hardness Value, converting the said shore hardness value into Surface Tessellation Language and transmitting the same to a third computer built into a 3D printing machine which selects a suitable material and its elasticity zone wise as per the Shore Hardness Value and 3D prints the same.

Claims

1) The process of manufacturing a customised split insole by processing; a. manually collected Medical Data, b. Plantar Pressure Distribution Data, and Foot Type Data collected using a computer enabled Plantar Pressure Measuring Device in a first computer, and c. manually collected Arch Data, in second computer where the Medical Data and Arch Data are directly manually fed into the second computer and converting the output projection data into a zone wise Ranking Index, and determining the elasticity of the material based on the Ranking Index and in turn allotting the Shore Hardness Value of the material zone wise, and then converting the said Shore Hardness Value into Surface Tessellation Language and transmitting it to a machine built third computer, which selects the suitable material and, the elasticity of the material, zone wise, as per the Shore Hardness Value and 3D prints the customised split insole.

2) An inventive process as in claim 1, where Medical Data consists of the name, age, height, weight, foot size, general or specific animus applicable to person.

3) An inventive process as in claim 1, where the Plantar Pressure Data is captured by 4 or 5 bare foot Trail Walks made by the person on the Plantar Pressure Measuring Device and stored in the First Computer whereupon the best Trail Walk Data is manually selected and sent along with the foot type data also captured by the Plantar Pressure Measuring Device and stored in the First Computer, to the Second Computer.

4) An inventive process as in claim 1, wherein the arch data as recorded using Foot Arch Measuring Board is manually fed into the second computer and the Foot Template is manually selected in the second computer from pre-stored Foot Template Data.

5) An inventive process as in claim 1, wherein the second computer processes the Pressure Distribution Data, Foot Type Data, Arch Data and the selected Foot Template, to generate the projection data plotted as a Ranking Index.

6) An inventive process as in claim 1, where the elasticity of the material to be used is determined based on the Ranking Index and the corresponding Shore Hardness Value is assigned to it.

7) An inventive process as in claim 1 where the Shore Hardness Value is uniform throughout a zone, depending on the peak pressure points on the plantar surface of the foot and the corresponding elasticity of the material for that particular plantar surface of the zone, but varies zone-wise.

8) An inventive process as in claim 1, where the Shore Hardness Value is converted into Surface Tessellation Language and transmitted to the Third Computer which in turn is built in to Polyjet Technology, Objet Connex Machine.

9) An inventive process as in claim 1, where the Third Computer selects the material which is VeroClear RGD810, TangoPlus FLX930, and the quantity of material to be used zone wise corresponding to the Shore Hardness Value of each zone which is A40, A50 and A60 respectively for normal and flat foot persons and 3D prints the customised split insole accordingly.

10) An inventive process as in claim 1, where the Third Computer selects the material which is VeroClear RGD810, TangoPlus FLX930, and the quantity of material to be used zone wise corresponding to the Shore Hardness Value of each zone which is A40 and A60 for high arch persons and 3D prints the customised split insole accordingly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG. 1 is a process sequence.

[0040] FIGS. 2A to 2C are a person walking on the pressure sensor pad.

[0041] FIG. 3 is plantar pressure distribution and foot type.

[0042] FIG. 4 is a plant pressure distribution, best trial walk.

[0043] FIG. 5 is an arch measuring foot board.

DESCRIPTION OF THE INVENTIVE PROCESS

[0044] The process of making a customized split insole under the present inventive process is as described in FIG. 1. Under this inventive process, various data pertaining to the foot of the diabetic patient is collected manually and technically, and processed to get the projective data based on which the hardness of the material and type of material to be used is determined, and then the customized split insole printed by the machine designed for such purpose. The following types of data are collected and processed; [0045] i. Medical datawhich is manually collected by the technician by a one to one interaction with the patient. This data serves to identify the individual for whom the insole is made and to bring on record the patients name, age, height, weight, foot size and general or specific animus as applicable to the patient. [0046] ii. Plantar pressure distribution datathis data pertains to the pressure exerted by the patients' foot on the floor. This data is collected by making the patient walk bare foot for four or five times on the sensor pad of a special equipment and stored in the first computer, and then selecting the best Trial Walk data manually. [0047] iii. Foot Type Datais the data pertaining to the type of foot of the patient i.e. whether normal, flat or high arch foot. This data is also collected when the patient walks four or five times on the sensor pad of the special equipment. This data so collected is also stored in the first computer. [0048] iv. Arch dataThis data pertains to the type of foot i.e. normal, flat or high arch foot and is obtained by physical measurement of the foot using an Arch Measuring Foot Board.

[0049] The selected plantar pressure distribution data and the foot type data which are collected by the sensor pad and stored in the first computer are transmitted to the second computer.

[0050] The arch data collected manually is also directly fed into the second computer. The foot template is manually selected in the second computer.

[0051] The second computer processes the selected plantar pressure distribution data and, the foot type data received from first computer, the arch data, selected foot template and generates the projection data which is then converted into Surface Tessellation Language in the second computer itself. This forms the instruction basis on which the insole is to be made. This data determines the type and hardness of the material to be used in each zone of the split insole, and the nature of projections.

[0052] The Surface Tessellation Language instruction from the second computer is transmitted to the third computer which is built into a 3D printing machine which prints the customized split insole as per the instruction received from the second computer, by choosing/selecting the appropriate material of requisite Shore Hardness Value.

Working of the Inventive Process

[0053] The foot profile of each individual is different, in terms of size, shape, plantar pressure distribution and gait pattern. Therefore a uniform material composition for foot insole is not suitable. This is because each individual's peak pressure point and gait pattern will vary. The design of the split insole is made according to an individual's foot type and plantar pressure distribution, so as to dissipate the pressure build up on the peak pressure points.

[0054] In this inventive process, the medical data of the person such as, his name, age, height, weight and foot size are collected manually. Then the person for whom the customized foot insole is to be made is made to walk on a Plantar Pressure Measuring Device as in FIG. 2. The measurement of plantar pressure using the Plantar Pressure Measuring Device provides the distribution of force over the plantar surface of the foot and thus provides detailed information specific to each region of the foot that can be separately addressed. The person is made to undergo trial walk on bare foot for four to five times or more, on this device. During which time the data on plantar pressure distribution is captured. The foot type viz. normal, flat or high arch foot is also captured by this device. All the captured data are stored in a computer (first computer) as in FIG. 1.

[0055] The best Trial Walk is manually ascertained from the four or five trials or more and stored in the first computer. The best Trial Walk is ascertained by considering the gait pattern (in particular gait pattern at heal strike and toe off) and consistency of plantar pressure distribution, the total contact area comprising of the peak pressure, distribution in all the trials, individual zone peak pressure and plantar pressure distribution pattern on the plantar surface. By considering these factors, the best trial walk is manually selected and sent to the second computer along with the data on the foot type.

[0056] However, any abnormality in the gait pattern, ambiguity at heal strike and toe-off, any consistency in peak pressure and contact area, non-similar pressure patterns, abnormal contact area and abnormal plantar pressure are not considered in selecting the best Trial Walk, because that is not his normal walking style/gait pattern.

Example 1

[0057] A total of four trial walks were performed on each foot and the same were compared to select the best trial walk for the design purpose. By comparing the four trials abnormal gait pattern is found in trials 1, 2 and 4 in the metatarsal region. Ambiguity in the gait pattern is found in heel strike as in trial 4. Variation in the contact area and peak pressure consistency are found in trials 2 and 4. Abnormal peak pressures 375 and 710 kPa is found in the trial 2 and 4 respectively, so the trial 1, 2 and 4 were excluded and trial 3 is selected for designing the customized split insole.

[0058] The trial walks which are stored in the first computer are stored as graphical representations. Thus, the Plantar Pressure Measuring Device collects the plantar pressure data stored in the first computer which analyses the same based on the plantar pressure exerted on the contact areas of the foot and the ground and represents it geometrically and graphically in pre-dimensional manner as in FIG. 4. The best Trail Walk and the foot type are then manually selected and transferred to the second computer. The arch data taken separately is also fed manually into the second computer. The Foot Template is selected from the set of pre-stored sizes in the second computer. The second computer then processes all the data and gives the projection data.

[0059] The best Trial Walk data which is manually selected from the trial walks as in FIG. 4 is called Plantar Pressure Data. The plantar pressure distribution on the manually selected best trial walk is as shown in FIG. 4. The report of pressure build-up is indexed in various colours with the pressure units indicating the pressure build-up and the pressure reading. The same is as analysed in Table 1 below:

TABLE-US-00001 TABLE 1 Analysis of FIG. 4 S. No Colour Pressure Build up Pressure Rating 1 Pink 300 kPa and above Dangerously high 2 Red 220 kPa to 299 kPa Very high 3 Yellow 150 kPa to 219 kPa High 4 Green 100 kPa to 149 kPa Normal 5 Light blue 60 kPa to 99 kPa Moderate 6 Dark blue 30 kPa to 59 kPa Low 7 Black 10 kPa to 29 kPa Very low 8 White No

[0060] From the above Table-1 which is an analysis of FIG. 4 it can be seen that the areas highlighted in pink, red and yellow are peak pressure build up areas and are more vulnerable to nerve and tissue damage and the chances of ulcer formation is very high. More is the area of pink colour, the chances of ulcer formation is highest and once formed ulcer would be very severe and chances of healing are very low, which directly increase the chance of gangrene formation and amputation.

[0061] Therefore, pink and red colour is directly proportional to high risk ulcer formation, and poor healing and thereby leading to high possibility of gangrene formation.

[0062] The projections offload the pressure build up in the pink, red and yellow areas to the other normal, moderate or low pressure areas so as to offload the pressure build up in the said areas. From FIG. 4 and Table-1 it is seen that the pressure build up is more in the metatarsal region (53 cm2), heel region (40.5 cm2). It is moderate or above moderate in the phalanges except the big toe and normal in the lateral foot and negligible in the midfoot. As regards the big toe (1st phalange) the pressure build up varies depending on the gait pattern.

[0063] Using the medical data collected from the patient, the appropriate pre-programmed foot template is manually selected in the second computer, to suit the opted foot size. The template is the size of the foot which is preset for various foot sizes, ranging from Size 6 to 11, which are the mostly used templates for this purpose.

[0064] The Arch Data is collected separately and physically using a device called Arch Measuring Foot Board, which consists of a measuring board, 7 grooves, and 7 triangular wooden pegs, on each side of the grooves, as in FIG. 5. The arch data is collected depending on the foot type i.e. normal, flat and high arch foot. The significance of providing arch support is that it will help in offloading the peak pressure across different anatomical zones and increases the surface area of contact of the foot with the ground.

[0065] The person places his foot on the foot board in between the two set of triangular wooden pegs. Then for normal and flat foot persons, the pegs on the side of the foot arch are adjusted by bringing them close to the foot and the arch reading taken. For high arch foot persons, the pegs on both sides of the foot are adjusted by bringing them close to their respective side of the foot and the readings taken. The data so collected is manually fed directly to the second computer.

[0066] Then the second computer processes the plantar pressure distribution data and foot type data as received from first computer along with the arch data directly fed into the second computer and based on the foot template manually selected generates the projection data. The projections data ultimately enables even distribution of pressure on the plantar surface of the foot, by suitable projections, as required to offload pressure buildup in the various areas of the plantar surface and to increase the plantar contact area with the insole.

[0067] For generation of the projection data, the plantar surface of the foot is ranked into six zones for normal and flat foot persons. For persons with high arch foot, it is split into five zones. The pressure points in the plantar surface are ranked zone wise based on a Ranking Index. For each Ranking Index, Shore Hardness Value for the corresponding elasticity is as furnished in Table 2 below:

TABLE-US-00002 TABLE 2 Material and shore hardness value Ranking Index Shore Hardness Values 1 2, 3, and 4 Shore Hardness Value A40 and A50 5 Shore Hardness Value is A60

[0068] From the table, it is seen that the zone wise pressure point ranking is given with reference to the Ranking Index and the elasticity is expressed in terms of Shore Hardness Value.

[0069] The Ranking Index of table 2 shows that where the index is 1 the pressure build-up is very high implying that these are areas of peak pressure build-up. As the Ranking Index value decreases, the pressure build-up decreases. For the maximum ranking index value, the elasticity of the insole material to be used at that particular zone is to be maximum, implying that the Shore Hardness Value by which it is expressed is to be minimum.

[00001]$\begin{array}{c}\begin{array}{c}\mathrm{Ranking}.Math..Math.\mathrm{Index}.Math..Math.\mathrm{Value}.Math..Math..Math..Math.\mathrm{Elasticity}\end{array}\\ \left(\mathrm{or}\right)\\ \begin{array}{c}\mathrm{Ranking}.Math..Math.\mathrm{index}.Math..Math.\mathrm{value}.Math..Math..Math.\frac{1}{\mathrm{Shore}.Math..Math.\mathrm{Hardness}.Math..Math.\mathrm{Value}}\end{array}\end{array}$

[0070] It can therefore be seen that if the ranking index is more, then the pressure acting on that point is more, in which case, the elasticity is also more and the Shore Hardness Value is less and vice-versa.

[0071] Now, the shore hardness value for each zone is arrived at. Therefore, the net result of the process of all the said data by the second computer is the projection data expressed in Shore Hardness Value for the various zones of the customised split insole. These Shore Hardness Value is now converted by the second computer into the machine readable instruction in Surface Tessellation Language and transmitted to the third computer which forms part of the machine which 3D prints the customised split insoles.

[0072] The machine used for 3D printing is the Polyjet Technology Objet Connex Machine which functions using addictive manufacturing technique. This machine is operated by a built in third computer. The third computer based on the input instruction received from the second computer in Surface Tessellation Language selects the appropriate material to be used for 3D printing based on the shore hardness value received.

[0073] The material used is VeroClear RGD810, TangoPlus FLX930 of Shore Hardness Value A40, A50 and A60 for normal foot persons and flat foot persons respectively and is VeroClear RGD810, TangoPlus FLX930 of Shore Hardness Value A40 and A60 for High arch persons. The selection of material for the appropriate shore hardness value and appropriate foot type for each zone is as furnished in Table 3. The third computer chooses the quantity and type of material and its thickness to suit the Shore Hardness Value for each zone and 3D prints the customized split insole.

TABLE-US-00003 TABLE 3 Shore Hardness Value Material Type of Foot TangoPlus FLX930 Normal, Flat and High Arch foot A40 VeroClearRGD810, Normal, Flat and High Arch foot TangoPlus FLX930 A50 VeroClearRGD810, Normal, and Flat Arch foot TangoPlus FLX930 A60 VeroClearRGD810, Normal, Flat and High Arch foot TangoPlus FLX930

Advantages of the Present Inventive Process

[0074] 1. No separate dies, templates or fixtures are required as in conventional models, [0075] 2. The time taken to make the product is less than that of any other insole manufacturing process, [0076] 3. Inventory holding cost of raw material is drastically reduced, [0077] 4. Wastage of raw material is negligible in the present invention whereas it is quite high in conventional manufacturing processes. [0078] 5. Replacement cost is very low [0079] 6. Life of insole is high as only worn out parts need by replaced and not the entire insole. [0080] 7. Effective distribution of plantar pressure is achieved.