Preliminary experiences with the CIR casting system for transtibial prosthetic sockets

Assessment of Socket Pressure during Walking in Rapid Fit Prosthetic Sockets

(1) Background: A sustainable casting system that combines the use of a polystyrene bag, a prosthetic liner and a vacuum system was developed to reduce fabrication time while maintaining comfort for the trans-tibial prosthesis user. (2) Methods: Eight prosthetists (28.7 ± 8.25 years old) fit ten trans-tibial prosthesis wearers (46 ± 12.4 years old) with two types of total surface bearing (TSB) prostheses; a polystyrene bead (PS) prosthesis and a plaster of paris (POP) prosthesis. Duration of casting and combined mean peak pressure was measured at six locations on the residual limb using Force Sensing Resistors (FSR). A pressure uniformity score (%) was determined. Socket Comfort Scale (SCS) was also measured. (3) Results: Duration of casting for the POP method was 64.8 ± 9.53 min and 7.8 ± 2 min for the PS method, (p = 0.006). Pressure uniformity in the POP prosthesis was 79.3 ± 6.54 and 81.7 ± 5.83 in the PS prosthesis (p = 0.027). SCS in both prosthesis types were equivalent. (4) Conclusion: A rapid fit PS prosthesis was developed, with significantly shorter duration than the traditional POP method. Socket pressure uniformity was confirmed and improved in the PS method. Socket comfort was equal between the two prothesis types.

Influences and trends of various shape-capture methods on outcomes in trans-tibial prosthetics: A systematic review

INTRODUCTION

In trans-tibial prosthetics, shape-capture methods are employed to create a representation of the residuum. Shape-capture methods can be grouped into the categories of 'hands-on', 'hands-off' and computer-aided design.

OBJECTIVE

This review examines the influences and trends of shape-capture methods on the outcomes of quality, comfort of user and clinical efficiency, in the population of trans-tibial prosthesis users.

STUDY DESIGN

Systematic Review.

METHOD

Databases and relevant journals were searched. Participants included trans-tibial prosthetics users/limb models. Interventions included shape-capture methods. Outcomes included quality, comfort of user and clinical efficiency.

RESULTS

Overall, 22 papers were evaluated; 8 papers evaluated hands-on and hands-off methods, 2 evaluated computer-aided design and 12 evaluated measurement systems used with shape capture. No papers relating to clinical efficiency were found.

CONCLUSION

Overall evidence was weak in suggesting that effects on outcomes were due to the sole influences of shape capture. However, studies suggest that hands-on methods are dependent on a prosthetist's skill. Hands-off methods, although repeatable, might still require experience to attain a good fit. Computer-aided design studies were mostly done on theoretical models. Shape-capture measurements require more consistent 'gold standards'. The relation between socket fit and comfort is still unclear. Overall, more research is required in each area.

CLINICAL RELEVANCE

A good fitting prosthetic socket is crucial for efficient and comfortable use of a prosthesis. To attain the best chances of a good fit, it is important that the characteristics of the residuum are captured as accurately as possible during the initial "shape capture" stage. This paper attempts to categorize and evaluate the existing shape capture methods on their influence and trends on various outcomes - Quality of shape capture, comfort of user and clinical efficiency.

Dilatancy-based impression and fabrication technique for custom foot orthoses

BACKGROUND AND AIM

Current methods used to take impressions for custom foot orthoses include plaster bandage, foam box, fiberglass, and laser-optical scanner. Impressions are converted to positive plaster or foam models. These methods create waste and may not be feasible in resource-limited areas. This technical note presents an alternative, greener impression and fabrication technique for foot orthoses that utilizes the dilatancy principle.

TECHNIQUE

Steps of the dilatancy (vacuum-based) procedure include taking an impression of the foot, converting the negative mold to a positive sand model, modifying the positive sand model, and thermoforming the foot orthosis.

DISCUSSION

This plaster-less system is inexpensive to set up and maintain, is reusable thereby minimizing cost and waste, and is clean to use. It enables a practitioner to quickly take an impression for fabricating a foot orthosis in a short period of time during a single clinic visit by the patient.

CLINICAL RELEVANCE

The dilatancy casting system could potentially be a cheaper, faster, and greener alternative procedure for fabricating custom foot orthoses in both developing and developed countries.

A scoping literature review of the provision of orthoses and prostheses in resource-limited environments 2000-2010. Part two: research and outcomes

BACKGROUND

Despite the activities of many orthotic and prosthetic provision organizations in resource-limited environments, there is still a great need and there are several areas for improvement, as identified in Part One of this series.

OBJECTIVES

Our goal was to examine outcomes and conclusions of research studies to produce an evidence base for determining factors that may lead to successful provision of orthoses and prostheses in resource-limited environments.

STUDY DESIGN

Literature review.

METHODS

We conducted a scoping literature review of all information related to orthotic and prosthetic provision in resource-limited environments published from 2000 to 2010. We extracted measured outcomes reported in all types of articles and analyzed conclusions from research studies.

RESULTS

Reported outcomes included durability, cost, satisfaction, use/nonuse of device, amount of utilization, walking speed, discomfort, pain, fit, misalignment, capacity for service provision, number of devices produced or delivered, and number of graduates from training programs.

CONCLUSIONS

There are many gaps in the evidence base, notably in measuring inclusion, participation, and quality of life for orthosis and prosthesis users in resource-limited environments. There is a paucity of reported outcomes for orthotics. Valid, reliable, and standard methods of data collection and reporting are needed to advance the field and enhance the evidence base.

A scoping literature review of the provision of orthoses and prostheses in resource-limited environments 2000-2010. Part one: considerations for success

STUDY DESIGN

Literature Review

BACKGROUND

We estimate that over 29 million people worldwide in resource-limited environments (RLEs) are in need of orthotic and prosthetic (O&P) devices and services.

OBJECTIVES

Our goal was to ascertain the current state of O&P provision in RLEs and identify factors that may lead to more successful O&P provision.

METHODS

We conducted a comprehensive scoping literature review of all information related to O&P provision in RLEs published from 2000 to 2010. We targeted Vietnam, Cambodia, Tanzania, Malawi, Colombia, and the Navajo Nation, but also included information about developing countries in general. We searched academic databases and grey literature. We extracted information from each article in the areas of design, manufacturing, distribution, service provision, and technology transfer.

RESULTS

We identified commonly reported considerations and strategies for O&P provision from 431 articles. Analysis of expert consensus documents revealed recurring themes for improving O&P provision. We found that some suggestions from the consensus documents are being followed, but many are overlooked or have not yet been implemented.

CONCLUSIONS

Areas for improvement include conducting field testing during the design process, providing services to rural environments, offering follow-up services, considering government collaboration, and encouraging an active role of the orthosis/prosthesis user. Outcomes and research studies will be further discussed in Part Two.

Assistive technology in developing countries: a review from the perspective of the Convention on the Rights of Persons with Disabilities

BACKGROUND

The 'Convention on the Rights of Persons with Disabilities' (CRPD) requires governments to meet the assistive technology needs of citizens. However, the access to assistive technology in developing countries is severely limited, which is aggravated by a lack of related services.

OBJECTIVES

To summarize current knowledge on assistive technology for low- and lower-middle-income countries published in 1995 or later, and to provide recommendations that facilitate implementation of the CRPD.

STUDY DESIGN

Literature review.

METHODS

Literature was searched in web-based databases and reference lists. Studies carried out in low- and lower-middle-income countries, or addressing assistive technology for such countries, were included.

RESULTS

The 52 included articles are dominated by product oriented research on leg prostheses and manual wheelchairs. Less has been published on hearing aids and virtually nothing on the broad range of other types of assistive technology.

CONCLUSIONS

To support effective implementation of the CRPD in these countries, there is a need for actions and research related particularly to policies, service delivery, outcomes and international cooperation, but also to product development and production.

CLINICAL RELEVANCE

The article has a potential to contribute to CRPD compliant developments in the provision of assistive technology in developing countries by providing practitioners with an overview of published knowledge and researchers with identified research needs.

Twenty-one months' experience with the PF-modified CIR casting system for trans-tibial prostheses

BACKGROUND

Shortly after the Centre for International Rehabilitation (CIR) casting system was demonstrated in Thailand, the Prostheses Foundation (PF) started modifying this system.

OBJECTIVES

To make the process suitable for the Foundation's main activities, namely clinical service at its main workshop, mobile clinics and satellite workshops.

STUDY DESIGN

Clinical trial.

METHODS

The development of the PF-modified CIR casting system took nine months, with the final PF-system launched in January 2008. Since then it has been used extensively at the Foundation's main workshop and also during mobile clinics.

RESULTS

By September 2009, a total of 1030 trans-tibial and Symes prostheses had been made by this system, and the Foundation had trained more than 200 personnel. Personnel training has been widespread and the PF-system is now being implemented at all satellite workshops around Thailand and at a clinic in Acheh province, Indonesia.

CONCLUSIONS

Using the PF-modified CIR system has simplified the Foundation's work.

CLINICAL RELEVANCE

The PF-modified CIR casting system is demonstrated as the successful method for making of the prosthetic socket. This provides faster and more practical way than the original CIR system which gain the benefit for the amputees who live in the remote area. The PF-modified system can be implemented to other parties who interest as our satellite workshops began to operate this system in their workshops.

Lower-limb prosthetic technologies in the developing world: A review of literature from 1994-2010

In the mid-1990s, a number of key publications and meetings of experts identified major technical issues associated with prosthetic technologies intended for developing countries. These included inadequate durability of prosthetic feet, poor socket quality and prosthetic fit, improper alignment of prostheses, and inferior function of components. To examine the progress that has been made since then in addressing these issues, a comprehensive review of literature was performed. In total, 106 articles were selected and included in the review. The review examined prosthetic technologies categorized into feet and ankles, knees, sockets and suspension, and materials, structures, and alignment methods. Moreover, publications were categorized as technical development, clinical (lab-based) testing, or clinical field testing studies. The results reveal important work that has been carried out to develop and implement standardized outcome measures during field testing, allowing various existing prosthetic technologies to be evaluated in terms of their use, function, durability, and other factors. Progress has also been made toward addressing the aforementioned limitations of prosthetic technologies, however, more research and development is required. This includes improving the durability of the external cosmetic features of prosthetic feet, developing more functional prosthetic knee joints, and simplifying fabrication techniques to further improve outcomes associated with socket fit and prosthetic alignment. Research and development collaborations between developed and developing countries, and the dissemination of ongoing research, development, and evaluation activities are essential to the advancement of prosthetic technologies in these regions.