Although some of the designs were developed by those with arthritis themselves, many of the arthritis aids available on the Internet were made by makers that know patients or by groups like Makers Making Change. It should be pointed out that the 20 case study adaptive aids used here are a tiny fraction of the aids of all kinds already available in the numerous 3-D printing free design repositories that now hold millions of designs of all manner of products [ 34 ]. It should also be noted that for some of these adaptive aids, a patient would want more than one copy of the aid (e.g., drawer, light switch, key, and handle adapter aids) and thus the twenty example case study products shown here could provide the capital savings alone for the purchase of one of the lower-cost fused filament-based 3-D printers.

Ninety-four percent savings are substantial enough for a person with arthritis to consider gaining access to a 3-D printer, whether purchasing and operating it themselves, using one at the local library, makerspace, fablab, or an online service (e.g., Shapeways). Thus, it should be clear that although the highest level of savings are for patients to print their own aids, those with arthritis can still get 3-D printed aids from any number of 3-D printing services including major retailers and shippers as well as local 3-D printing on demand services such as MakeXYZ. It should be pointed out that the markup for commercial online services could erode the savings shown here, but would depend on the service as well as provide a wider selection of materials (e.g., metal) that may make for a more robust aid. It is clear that the savings per adaptive aid are high enough that margins could be maintained by also including labor costs although this would be highly variable depending on the community. All of the adaptive aids shown in Figure 1 can be fabricated reasonably easily with a desktop 3-D printer and basic assembly skills (e.g., no machinist or other specialty skills are necessary). However, it should be pointed out that someone suffering from severe hand arthritis may need assistance assembling (e.g., tightening down M3 nuts and bolts for some of the designs like the scissor aid ( Figure 1 a), knife holder ( Figure 1 f), key holder ( Figure 1 m), and pill splitter ( Figure 1 t)).

Similar to previous work that has shown substantial economic savings for 3-D printing high-end scientific tools [ 77 82 ], it is clear that distributed manufacturing can radically reduce the cost of producing adaptive aids for those with arthritis. Despite the relatively high proportion of the population with arthritis (particularly the geriatric population), the market for adaptive aids is still much smaller than conventional consumer products and thus economics of scale have not driven down the costs of adaptive aids. This savings potential is also likely because similar to scientific equipment that often needs to be quasi-personalized, the ability of the 3-D printer to make a bespoke product for a specific problem for someone with arthritis provides the highest value. All of the designs shown in Figure 1 were either made with OpenSCAD ( http://www.openscad.org/ ) or FreeCAD ( https://www.freecadweb.org/ ), both of which are natively parametric CAD packages allowing relatively easy customization for those with access to the raw source files. This was the case for all the designs selected because of criteria 2. In addition, customizer applications have been developed for OpenSCAD that enabled novices to customize products with no knowledge or experience with CAD because of a simple user interface [ 83 ]. This makes the designs accessible even to those with only modest technical and computer competency. 3-D printing itself has also become considerably more user friendly and for the use of standard materials (like the PLA used in this study—criteria 5) and straightforward prints, the files are easily printed akin to printing a document on a conventional 2-D printer.

Lastly, all economic analyses completed in this study focused on the U.S. market. It is likely that similar economic savings could be found for other regions of the world including Central and South America, Europe, Oceania, Asia, and Africa, but further work is needed to demonstrate this with the same detailed analysis. Many regions in the world (e.g., Europe) would have higher costs for imported items because of VAT or tariffs. This complicates the analysis because not only does the cost of the commercial adaptive aid change, but so does the cost of 3-D printing filament. Also, in many areas of the world with a less robust 3-D printer market, low-cost 3-D printing filament may not be as easily accessible. This lack of access can be offset with the use of recycled locally-manufactured filament [ 45 ], which would also further reduce the costs of manufacturing arthritis aids.

The largest savings are generally seen for products that can be completely 3-D printed. Some of the examples shown here such as pen holder aid ( Figure 1 j), typing aid ( Figure 1 n), light switch aid ( Figure 1 d), and car seat aid ( Figure 1 b). The car seat aid for example makes use of a 3-D printed living hinge, which is an advanced technique for changing the rigidity of different parts of a 3-D printed component to allow a higher function. Future designs should make of such innovations to reduce the need for non-printed components in a design. Further work is also necessary to go beyond adaptive aids for hand arthritis and could for example look at those to improve mobility, which has been shown to be a major factor in patient quality of life [ 88 ]. Further work is needed to better optimize the function of all the designs, making them easier to print, assemble, and use. Although all the adaptive aids analyzed in this study were able to perform their mechanical functions, further study is needed to have the devices evaluated by patients in different age groups to ensure they are technically proficient at performing their functions. If there are discrepancies found, they should be re-designed and tested.

This was a preliminary investigation into the technical and economic potential for adaptive aids for arthritis patients that specifically focused on arthritis of the hands and thus could be significantly expanded in the future. First, designs for adaptive aids for other types of arthritis could be similarly evaluated. Second, an entire catalog of open-source 3-D printable equivalents for all commercial adaptive aids could be developed and then submitted to the same study as was done here. The economic analysis here assumed a similar lifetime for the 3-D printed products and the conventionally manufactured products. This assumption would need to be carefully analyzed and the products tested over long time periods to determine lifetimes to do full life cycle economic analysis. Many products like the light switch extender ( Figure 1 d), pen holder ( Figure 1 j) or toothbrush holder ( Figure 1 s), which do not undergo significant mechanical stresses would likely perform over long periods the same as an injection-molded component, however, others that undergo significant stresses may not be as robust (e.g., the pill splitter shown in Figure 1 t). The pill splitter design, for example, may need to be optimized by both removing the bolts and using filament rivets, which would eliminate the cost of fasteners, while at the same time adding in a metal blade instead of a replaceable polymer one (that would increase the cost). Like all free and open-source projects the designs shown here, although certainly technically useable, could be further improved and the open-source nature of them is an invitation to do just that [ 84 86 ]. This concept of continual improvement and innovation is a challenge in healthcare [ 87 ]. The nature of adaptive aids being consumer products meant to improve the quality of life of patients may be the first step into applying the more rapid innovation cycles well-established in the open source technology design world to medical care.

These readily 3-D printable objects can have a great effect on the community. For example, consider a person was leaving her apartment because her family came to pick her up. When she returns, she must figure out the best way of holding a small key and inserting it into the lock in the door. What if she had a Key Case ( Figure 1 m) that allowed her to both find her key faster in her purse because of its size and assisted her in turning the key to unlock the door. Not only are these designs easily accessible, but they are easily modified to accommodate the person for which the design is being made. This open source distributed manufacturing methodology has the potential to significantly alter the way the majority of arthritis sufferers adapt to their condition by providing a far more affordable option for many patients all over the United States (and potentially the rest of the world).

The largest potential savings for the arthritis patients are if they are able to manufacture the aids themselves. Although arthritis can impair the young, arthritis relevance increases with age and the geriatric population is the one that would benefit the most from this technological development. However, it remains unclear if older patients would have the appropriate technological knowledge to 3-D print their own aids. Future work is necessary to evaluate this along with the ability of all ages of arthritis patients to search for and identify open source 3-D-printable designs online. A study could be done to confirm that the time it takes arthritis patients from all age groups to search for the 3-D-printable design online is approximately equivalent to the time needed for shopping for the equivalent product online as it is for experienced 3-D printer users. This future clinical trial could consider a significant number of patients, grouped in different grades of arthritis conditions who are asked to determine the difficulty to print out the aids, degree of satisfaction, useful of the aid, support received, self-capability to find objects in a catalogue or online, run the 3-D printer and fabricate the object, as well as their subjective cost to effort value received.

Arthritis does not only take effect in elderly people above the age of 65, but also on otherwise healthy members of the younger generations. For example, Caroline Wozniacki, a professional tennis player, was diagnosed with rheumatoid arthritis at age 28, just a few weeks before the U.S. Open this year. Wozniacki spoke about how she is working with her diagnosis to overcome her hardships and work toward a goal of creating a positive mindset for herself [ 89 ]. A study from 2001–2004 by the National Ambulatory and Medical Care Survey, found there were approximately 294,000 children ages 0–17 years that were affected by arthritis or some other rheumatic condition [ 90 ]. A large population of the children in the U.S. that have these conditions may not have the tools or resources to work with their diagnosis as easily as a life-experienced adult or professional athlete. By using these 3-D printed aids from an open source file, such as the toothbrush holder ( Figure 1 s) or the zipper pull ( Figure 1 h), the children will not have as difficult of a time going about their daily routines.

4.4. Deployment of 3-D Printers as Manufacturing Tools in Context

$ 5,700 and $ 9,600 yearly [ $ 140 billion in 2013 [ Arthritic diseases cause significant morbidity, costing patients between5,700 and9,600 yearly [ 91 ]. With an estimated 54.4 million adults in the USA suffering from arthritic conditions [ 92 ], the economic burden of medical costs for arthritic conditions was estimated at approximately140 billion in 2013 [ 93 ] and is expected to grow as the population ages and as obesity affects a greater proportion of the population [ 92 ]. Patients suffering from arthritis often have difficulty accomplishing both occupational tasks as well as ADLs. Private health insurance covers some doctor-prescribed assistive aids and Medicare Part B covers certain aids as Durable Medical Equipment (DME). Even with such cost-sharing, Medicare patients are responsible for all costs until their deductible is reached and for 20% of costs as copayments thereafter. Assistive aids are thus a significant expense for patients. As the population of arthritis patients increases as discussed above, so too will the costs associated with assistive aids. As the results of this study show, all of the open-source adaptive aids can be manufactured for less than the 20% copayment and thus it can be inferred that 3-D printing adaptive aids will be economic for Medicare patients as well as those with no insurance.

The type of assistive aids required by an individual patient depends on which of the patient’s joints are affected by the arthritis, the severity of the patient’s arthritis, the frequency with which they need to accomplish a particular task, and the force needed to go through the patient’s joints to accomplish the task. Modifications for various tasks can be done by using an alternative tool (i.e., using an electric can opener as opposed to a manual one), by retrofitting a patient’s home with accessible features (i.e., elevated toilet seats, grab bars in the bathroom, and 3-D printable aids such as door handles as opposed to door knobs [ 94 ] and automotive transfer handles [ 95 ]), or by changing a tool to make it more comfortable or appropriate to the task (adding a handle to a key to allow a handgrip to turn the key as opposed to a key pinch grip by the finger and thumb as shown in Figure 1 m). By using these strategies to modify activities that are painful for patients with arthritis, patients can perform tasks that they were previously not able to perform comfortably. This may lengthen the careers of arthritis patients and may also allow them to live independently at home for a longer period before requiring assisted living situations.

Deploying 3-D printers in doctor’s offices, where musculoskeletal complaints account for 13% of all visits, would allow for physicians to suggest, prescribe, and print properly customized and sized aids for their patients at the point of care when the patient presents with a complaint. This is one method by which patients could be educated on their disease and have their needs addressed in a practical manner by their physician without the need for opioids or other pharmaceuticals. Future work is needed to determine if this would create an increase in visits as patients want to customize, replace or obtain additional copies of a 3-D printed aid. In addition, how to provide compensation for the staff time needed to provide this service would need to be determined. In a similar way, 3-D printers could be very effectively used in physical therapists’ and occupational therapists’ clinics as many patients presenting to these health care providers have specific functional requirements for which they are seeking solutions. While strengthening the patient’s muscles and improving their joints’ range of motion will provide benefit to the patient, so too will the use of specific functional aids which the therapist could prescribe and customize to the patient in clinic before printing and fitting the aid to the patient.

Nursing homes and assisted living residences could also take advantage of having a 3-D printer on-site to be able to provide functional aids for their patients with physical limitations. Arthritis is a significant and underreported problem in nursing homes [ 96 ]. Patients with arthritis require more assistance with walking and ADLs than patients without a diagnosis of arthritis [ 96 ]. The nurses and nursing aides often observe patients having trouble with ADLs and struggle to provide assistance to all of the patients under their care. By providing patients with functional aids where they struggle with certain ADLs (for example, being unable to cut their food due to not being able to hold a knife properly but being able to cut their food with a knife modified with a large handle to enable a grasp hold on the knife or using a knife guide aid as shown in Figure 1 f), the patients may retain aspects of independence longer, have improved self-esteem, and free the staff from certain helping tasks.

Hospitals would also be able to offer their patients the benefit of 3-D printed assistive devices. Many patients present to hospital with new acute conditions, but also with undiagnosed chronic conditions as many of the elderly who live alone have either found a method of coping with their disabilities or simply avoid certain activities that they cannot accomplish independently. Upon evaluation in hospital, the opportunity arises to address some of these deficiencies and improve the patient’s level of function and activity. Arthritis is the most expensive condition treated in hospital by private health insurance in the U.S., and the second most expensive condition treated in U.S. hospitals overall in 2013 [ 97 ]. Hospitals could provide assistive devices to deal with temporary acute disabilities (such as from fractures or from joint replacement surgeries) as well as devices to help with chronic dysfunctions.