[Cost-revenue aspects of endovascular treatment of distal aortic arch pathologies with respect to the introduction of a new thoracic side-branch prosthesis]. / Kosten-Erlös-Aspekte der endovaskulären Versorgung distaler Aortenbogenpathologien im Hinblick auf die Einführung einer neuen thorakalen Seitenarmprothese.

BACKGROUND: The standard vascular surgical procedure (SV) for the treatment of distal aortic arch pathologies involves a hybrid approach using a left carotid-subclavian bypass and thoracic endovascular aortic repair. Considering the introduction of a thoracic side branch prosthesis (TBE), the aim of this study was to analyze the cost-revenue aspects of both procedures. MATERIAL AND METHODS: A retrospective analysis was conducted on cases treated by SV from 2017 to 2022. To draw conclusions regarding the use of TBE, the main diagnoses and procedures of SV were recoded based on current classifications (ICD/OPS 2023) for revenue calculations and regrouped according to aG-DRG 2023. An OPS modification and regrouping were performed for modeling TBE revenues. RESULTS: A total of 13 cases were identified (mean age 62.5 ± 13.8 years; 10 males). After regrouping, the following DRGs were obtained: F42Z in N = 5, F51A in N = 4, F08B in N = 2, and F07A and F36B each in N = 1. The total revenue after regrouping was €â€¯666,514.13, including an additional payment (ZE) of €â€¯132,729.14. With the modeled application of TBE, a total revenue of €â€¯659,212.19 was achieved. Compared to SV, this represents a revenue decrease of €â€¯16,886.71 (changed DRG), but with an increase in ZE revenue by €â€¯65,559.78 (different ZE). The use of TBE resulted in a saving of 74 occupancy days, including 13.5 days in intensive care. CONCLUSION: A cost coverage seems probable with a change in the procedure, despite the yet to be determined pricing of TBE. This is highly dependent on the coding quality and the future development of ZE, given the annually changing DRG relative weights. Precise and transparent performance and cost documentation are essential for determining the pricing.

Cost-effectiveness of dual-mobility components in patients with displaced femoral neck fractures.

AIMS: Total hip arthroplasty (THA) with dual-mobility components (DM-THA) has been shown to decrease the risk of dislocation in the setting of a displaced neck of femur fracture compared to conventional single-bearing THA (SB-THA). This study assesses if the clinical benefit of a reduced dislocation rate can justify the incremental cost increase of DM-THA compared to SB-THA. METHODS: Costs and benefits were established for patients aged 75 to 79 years over a five-year time period in the base case from the Canadian Health Payer's perspective. One-way and probabilistic sensitivity analysis assessed the robustness of the base case model conclusions. RESULTS: DM-THA was found to be cost-effective, with an estimated incremental cost-effectiveness ratio (ICER) of CAD $46,556 (£27,074) per quality-adjusted life year (QALY). Sensitivity analysis revealed DM-THA was not cost-effective across all age groups in the first two years. DM-THA becomes cost-effective for those aged under 80 years at time periods from five to 15 years, but was not cost-effective for those aged 80 years and over at any timepoint. To be cost-effective at ten years in the base case, DM-THA must reduce the risk of dislocation compared to SB-THA by at least 62%. Probabilistic sensitivity analysis showed DM-THA was 58% likely to be cost-effective in the base case. CONCLUSION: Treating patients with a displaced femoral neck fracture using DM-THA components may be cost-effective compared to SB-THA in patients aged under 80 years. However, future research will help determine if the modelled rates of adverse events hold true. Surgeons should continue to use clinical judgement and consider individual patients' physiological age and risk factors for dislocation. Cite this article: Bone Joint J 2021;103-B(12):1783-1790.

Cost Analyses of Prosthetic Devices: A Systematic Review.

OBJECTIVE: To synthesize extant literature on the cost-effectiveness of prosthetic interventions and explore applicability to low- and middle-income country (LMIC) settings. DATA SOURCES: A systematic literature review using subject headings including "prosthetics," "amputation," and "cost analysis" was performed with PubMed, Embase, and Web of Science search engines, yielding 1194 articles. An additional 22 articles were identified via backward citation searching for 1144 total after duplicate removal. The search was last run in May of 2019. STUDY SELECTION: Studies were included if they conducted an economic analysis of an upper or lower extremity prosthetic device. Studies were excluded if (1) full text was unavailable in English; (2) study was a systematic review or meta-analysis; or (3) study did not have a prosthetic comparison group. Using DistillerSR software, 2 authors independently conducted title and abstract screening. One author conducted full-text screening. The proportion of initially identified studies that met final inclusion criteria was 1% (12 of 1144). DATA EXTRACTION: Data were dually extracted by 2 authors and reviewed by 3 additional authors. DATA SYNTHESIS: All included studies (N=12) examined lower extremity amputations comparing advanced technology. No studies were conducted in LMICs. Comparable data between studies demonstrated (1) the cost-effectiveness of microprocessor- over nonmicroprocessor-controlled knees for transfemoral amputation in high-income settings; (2) equivocal findings regarding osseointegrated vs socket-suspended prostheses; and (3) increased cost for ICEX and modular socket systems over patellar tendon-bearing socket systems with no functional improvement. CONCLUSIONS: There are few prosthetic cost analyses in the literature. Additional analyses are needed to determine the direct and indirect costs associated with prosthetic acquisition, fitting, and maintenance; the costs of amputee rehabilitation; and long-term economic and quality-of-life benefits. Such studies may guide future prosthetic and rehabilitative care, especially in resource-austere settings where prosthetic needs are greatest.

Low-Cost, Three-Dimensionally-Printed, Anatomical Models for Optimization of Orbital Wall Reconstruction.

BACKGROUND: Orbital blowout fracture reconstruction often requires an implant, which must be shaped at the time of surgical intervention. This process is time-consuming and requires multiple placement trials, possibly risking complications. Three-dimensional printing technology has enabled health care facilities to generate custom anatomical models to which implants can be molded to precisely match orbital anatomy. The authors present their early experience with these models and their use in optimizing orbital fracture fixation. METHODS: Maxillofacial computed tomographic scans from patients with orbital floor or wall fractures were prospectively obtained and digitally reconstructed. Both injured-side and mirrored unaffected-side models were produced in-house by stereolithography printing technique. Models were used as templates for molding titanium reconstruction plates, and plates were implanted to reconstruct the patients' orbital walls. RESULTS: Nine patients (mean age, 15.5 years) were included. Enophthalmos was present in seven patients preoperatively and resolved in six patients with surgery. All patients had excellent conformation of the implant to the fracture site on postoperative computed tomographic scan. Postoperative fracture-side orbital volumes were significantly less than preoperative, and not significantly different from unfractured-side orbital volumes. Total model preparation time was approximately 10 hours. Materials cost was at most $21. Plate bending time was approximately 60 seconds. CONCLUSIONS: Patient-specific orbital models can speed the shaping of orbital reconstruction implants and potentially improve surgical correction of orbital fractures. Production of these models with consumer-grade technology confers the same advantages as commercial production at a fraction of the cost and time. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

An advanced prosthetic manufacturing framework for economic personalised ear prostheses.

Craniofacial prostheses are commonly used to restore aesthetics for those suffering from malformed, damaged, or missing tissue. Traditional fabrication is costly, uncomfortable for the patient, and laborious; involving several hours of hand-crafting by a prosthetist, with the results highly dependent on their skill level. In this paper, we present an advanced manufacturing framework employing three-dimensional scanning, computer-aided design, and computer-aided manufacturing to efficiently fabricate patient-specific ear prostheses. Three-dimensional scans were taken of ears of six participants using a structured light scanner. These were processed using software to model the prostheses and 3-part negative moulds, which were fabricated on a low-cost desktop 3D printer, and cast with silicone to produce ear prostheses. The average cost was approximately $3 for consumables and $116 for 2 h of labour. An injection method with smoothed 3D printed ABS moulds was also developed at a cost of approximately $155 for consumables and labour. This contrasts with traditional hand-crafted prostheses which range from $2,000 to $7,000 and take around 14 to 15 h of labour. This advanced manufacturing framework provides potential for non-invasive, low cost, and high-accuracy alternative to current techniques, is easily translatable to other prostheses, and has potential for further cost reduction.

From Concept to Counter: A Review of Bringing an Orthopaedic Implant to Market.

Physicians offer unique contributions to the orthopaedic implant design process by providing creative ideas and insightful clinical expertise. This article provides a brief overview of the pertinent considerations of transforming a concept into an orthopaedic implant and bringing it to the market. Implant concept choice should consider medical or surgical necessity, regional variability, market characteristics, cost of goods sold, and average selling price. Implant development requires adherence to regulatory requirements and device classification. Implant production incorporates design specifications, mechanical testing, sterilization, packaging, and marketing and sales. Orthopaedic implant company agreements determine physician compensation through royalties and/or the purchase of intellectual property. After rollout, physicians participate in monitoring for device safety. Bringing an orthopaedic implant from a concept to the market can be lengthy and complicated, but innovation is essential for advancing patient care and well-being.

User-relevant factors determining prosthesis choice in persons with major unilateral upper limb defects: A meta-synthesis of qualitative literature and focus group results.

OBJECTIVE: Considering the high rejection rates of upper limb prostheses, it is important to determine which prosthesis fits best the needs of each user. The introduction of the multi-grip prostheses hands (MHP), which have functional advantages but are also more expensive, has made prosthesis selection even harder. Therefore, we aimed to identify user opinions on factors determining prosthesis choice of persons with major unilateral upper limb defects in order to facilitate a more optimal fit between user and prosthesis. METHODS: A qualitative meta-synthesis using a 'best-fit framework' approach was performed by searching five databases (PROSPERO registration number: CRD42019126973). Studies were considered eligible if they contained qualitative content about adults with major unilateral upper limb defects experienced in using commercially available upper limb prostheses and focused on upper limb prosthesis users' opinions. Results of the meta-synthesis were validated with end-users (n = 11) in a focus group. RESULTS: Out of 6247 articles, 19 studies were included. An overview of six main themes ('physical', 'activities and participation', 'mental', 'social', 'rehabilitation, cost and prosthetist services' and 'prosthesis related factors') containing 86 subthemes that could affect prosthesis choice was created. Of these subthemes, 19 were added by the focus group. Important subthemes were 'work/school', 'functionality' and 'reactions from public'. Opinions of MHP-users were scarce. MHPs were experienced as more dexterous and life-like but also as less robust and difficult to control. CONCLUSION: The huge number of factors that could determine upper limb prosthesis choice explains that preferences vary greatly. The created overview can be of great value to identify preferences and facilitate user-involvement in the selection process. Ultimately, this may contribute to a more successful match between user and prosthesis, resulting in a decrease of abandonment and increase of cost-effectiveness.

Affordable passive 3D-printed prosthesis for persons with partial hand amputation.

BACKGROUND AND AIM: Partial hand amputations are common in developing countries and have a negative impact on patients and their families' quality of life. The uniqueness of each partial hand amputation, coupled with the relatively high costs of prostheses, makes it challenging to provide suitable prosthetic solutions in developing countries. Current solutions often have long lead times and require a high level of expertise to produce. The aim of this study was to design and develop an affordable patient-specific partial hand prosthesis for developing countries. TECHNIQUE: The prosthesis was designed for a patient with transmetacarpal amputation (i.e. three amputated fingers and partial palm). The final design was passive, controlled by the contralateral hand, and utilized the advanced flexibility properties of thermoplastic polyurethane in a glove-like design that costs approximately 20 USD to fabricate. Quantitative and qualitative tests were conducted to assess performance of the device after the patient used the final design. A qualitative assessment was performed to gather the patient's feedback following a series of tests of grasp taxonomy. A quantitative assessment was performed through a grasp and lift test to measure the prosthesis' maximum load capacity. DISCUSSION: This study showed that the prosthesis enhanced the patient's manual handling capabilities, mainly in the form of grasp stability. The prosthesis was light weight and could be donned and doffed by the patient independently. Limitations include the need to use the contralateral hand to achieve grasping and low grasp strength. CLINICAL RELEVANCE: Persons with partial hand amputation in developing countries lack access to affordable functional prostheses, hindering their ability to participate in the community. 3D-printed prostheses can provide a low-cost solution that is adaptable to different amputation configurations.

Cost-effectiveness and budget impact of the microprocessor-controlled knee C-Leg in transfemoral amputees with and without diabetes mellitus.

BACKGROUND: The safe use of a prosthesis in activities of daily living is key for transfemoral amputees. However, the number of falls varies significantly between different prosthetic device types. This study aims to compare medical and economic consequences of falls in transfemoral amputees who use the microprocessor-controlled knee joint C-Leg with patients who use non-microprocessor-controlled (mechanical) knee joints (NMPK). The main objectives of the analysis are to investigate the cost-effectiveness and budget impact of C-Legs in transfemoral amputees with diabetes mellitus (DM) and without DM in Germany. METHODS: A decision-analytic model was developed that took into account the effects of prosthesis type on the risk of falling and fall-related medical events. Cost-effectiveness and budget impact analyses were performed separately for transfemoral amputees with and without DM. The study took the perspective of the statutory health insurance (SHI). Input parameters were derived from the published literature. Univariate and probabilistic sensitivity analyses (PSA) were performed to investigate the impact of changes in individual input parameter values on model outcomes and to explore parameter uncertainty. RESULTS: C-Legs reduced the rate of fall-related hospitalizations from 134 to 20 per 1000 person years (PY) in amputees without DM and from 146 to 23 per 1000 PY in amputees with DM. In addition, the C-Leg prevented 15 or 14 fall-related death per 1000 PY. Over a time horizon of 25 years, the incremental cost-effectiveness ratio (ICER) was 16,123 Euro per quality-adjusted life years gained (QALY) for amputees without DM and 20,332 Euro per QALY gained for amputees with DM. For the period of 2020-2024, the model predicted an increase in SHI expenditures of 98 Mio Euro (53 Mio Euro in prosthesis users without DM and 45 Mio Euro in prosthesis users with DM) when all new prosthesis users received C-Legs instead of NMPKs and 50% of NMPK user whose prosthesis wore out switched to C-Legs. Results of the PSA showed moderate uncertainty and a probability of 97-99% that C-Legs are cost-effective at an ICER threshold of 40,000 Euro (≈ German GDP per capita in 2018) per QALY gained. CONCLUSION: Results of the study suggest that the C-Leg provides substantial additional health benefits compared with NMPKs and is likely to be cost-effective in transfemoral amputees with DM as well as in amputees without DM at an ICER threshold of 40,000 Euro per QALY gained.

Osseointegrated prostheses for the rehabilitation of amputees (OPRA): results and clinical perspective.

Introduction: Patients who undergo extremity amputation have historically used socket prosthetics to ambulate and perform daily functions; however, these prosthetics can be limited by poor terminal control and wear issues. In patients who have difficulty wearing their prostheses or with upper extremity amputations, osseointegrated implants may offer better function and quality of life. The Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) was the first such device to become commercially available. Clinical trials have demonstrated benefit in patient gait, prosthetic use, and overall well-being, and new implants may be applied for various amputation levels.Areas covered: The OPRA, the most studied osseointegrated prosthetic stem, is reviewed, presenting indications, surgical procedure, complications, and results of clinical studies.Expert commentary: Osseointegration for amputees is an expanding field that has the potential to enhance rehabilitative potential. The OPRA implant is an effective device with a long life-span and low complication profile.

Optimized control mapping through user-tuned cost of effort, time, and reliability.

Humans consistently coordinate their joints to perform a variety of tasks. Computational motor control theory explains these stereotypical behaviors using optimal control. Several cost functions have been used to explain specific movements, which suggests that the brain optimizes for a combination of costs and just varies their relative weights to perform different tasks. In the case of tunable human-machine interfaces, we hypothesize that the human-machine interface should be optimized according to the costs that the user cares about when making the movement. Here, we study how the relative weights of individual cost functions in a composite movement cost affect the optimal control signal produced by the user and the mapping between the user's control signals and the machine's output, using prosthesis control as a specific example. This framework was tested by building a hierarchical optimization model that independently optimized for the user control signal and the virtual dynamics of the device. Our results indicate the feasibility of the approach and show the potential for using such a model in prosthesis tuning. This method could be used to allow clinicians and users to tune their prosthesis based on costs they actually care about; and allow the platforms to be customized for the unique needs of every patient.

Conception, design, and fabrication of novel cost-effective partial-hand prosthetic devices for a quadrilateral individual with limb loss.

BACKGROUND AND AIM: The author designed customized upper-limb prosthetic devices for a 22-year-old man with quadrilateral limb loss. The devices were created to meet his functional requirements, while remaining cost-effective. What made this solution unique was that it utilized low-cost items that were easily sourced and maintained. TECHNIQUE: Devices with polypropylene sockets, wooden positional fingers from an artist's wooden hand and a metal extension plate were conceptualized and manufactured. The patient gave written consent to the publication of information and photographs in this report. DISCUSSION: The devices allowed the individual to complete tasks he desired to be able to perform independently, which included using a computer mouse, aided by the devices. The devices utilized were low-cost and easily accessible materials, such as polypropylene and wood, to cater to financial constraints. The final design had positional fingers and an extension plate to restore surface area for grip, support, and opposition to enable the execution of daily tasks of living. CLINICAL RELEVANCE: A cost-effective method of fabricating partial-hand devices with easily accessible materials is described. The resulting devices were successful at restoring the upper-limb surface area for improved grip, support, and opposition for performance of daily tasks.

Adoption of New Medical Technologies: The Case of Customized Individually Made Knee Implants.

OBJECTIVES: To investigate the impact of insurance coverage on the adoption of customized individually made (CIM) knee implants and to compare patient outcomes and cost effectiveness of off-the-shelf and CIM implants. METHODS: A system dynamics simulation model was developed to study adoption dynamics of CIM and meet the research objectives. The model reproduced the historical data on primary and revision knee replacement implants obtained from the literature and the Nationwide Inpatient Sample. Then the dynamics of adoption of CIM implants were simulated from 2018 to 2026. The rate of 90-day readmission, 3-year revision surgery, recovery period, time savings in operating rooms, and the associated cost within 3 years of primary knee replacement implants were used as performance metrics. RESULTS: The simulation results indicate that by 2026, an adoption rate of 90% for CIM implants can reduce the number of readmissions and revision surgeries by 62% and 39%, respectively, and can save hospitals and surgeons 6% on procedure time and cut down cumulative healthcare costs by approximately $38 billion. CONCLUSIONS: CIM implants have the potential to deliver high-quality care while decreasing overall healthcare costs, but their adoption requires the expansion of current insurance coverage. This work presents the first systematic study to understand the dynamics of adoption of CIM knee implants and instrumentation. More broadly, the current modeling approach and systems thinking perspective could be used to consider the adoption of any emerging customized therapies for personalized medicine.

Choice of Prosthetic Implant Combinations in Total Hip Replacement: Cost-Effectiveness Analysis Using UK and Swedish Hip Joint Registries Data.

BACKGROUND: Prosthetic implants used in total hip replacements (THR) have a range of bearing surface combinations (metal-on-polyethylene, ceramic-on-polyethylene, ceramic-on-ceramic, and metal-on-metal), head sizes (small [<36 mm in diameter] and large [≥36 mm in diameter]), and fixation techniques (cemented, uncemented, hybrid, and reverse hybrid). These can influence prosthesis survival, patients' quality of life, and healthcare costs. OBJECTIVES: To compare the lifetime cost-effectiveness of implants for patients of different age and sex profiles. METHODS: We developed a Markov model to compare the cost-effectiveness of various implants against small-head cemented metal-on-polyethylene implants. The probability that patients required 1 or more revision surgeries was estimated from analyses of more than 1 million patients in the UK and Swedish hip joint registries, for men and women younger than 55, 55 to 64, 65 to 74, 75 to 84, and 85 years and older. Implant and healthcare costs were estimated from local procurement prices, national tariffs, and the literature. Quality-adjusted life-years were calculated using published utility estimates for patients undergoing THR in the United Kingdom. RESULTS: Small-head cemented metal-on-polyethylene implants were the most cost-effective for men and women older than 65 years. These findings were robust to sensitivity analyses. Small-head cemented ceramic-on-polyethylene implants were most cost-effective in men and women younger than 65 years, but these results were more uncertain. CONCLUSIONS: The older the patient group, the more likely that the cheapest implants, small-head cemented metal-on-polyethylene implants, were cost-effective. We found no evidence that uncemented, hybrid, or reverse hybrid implants were the most cost-effective option for any patient group. Our findings can influence clinical practice and procurement decisions for healthcare payers worldwide.

Are Ceramic Bearings Becoming Cost-Effective for All Patients Within a 90-Day Bundled Payment Period?

BACKGROUND: We analyzed whether the total hospital cost in a 90-day bundled payment period for ceramic-on-polyethylene (C-PE) and ceramic-on-ceramic (COC) total hip arthroplasty (THA) bearings was changing over time, and whether the cost differential between ceramic bearings and metal-on-polyethylene (M-PE) bearings was approaching the previously published tipping point for cost-effectiveness of US$325. METHODS: A total of 245,077 elderly Medicare patients (65+) who underwent primary THA between 2010 and 2015 were identified from the United States Medicare 100% national administrative hospital claims database. The total inpatient cost, calculated up to 90 days after index discharge, was computed using cost-to-charge ratios, and hospital payment was analyzed. The differential total inpatient cost of C-PE and COC bearings, compared to metal-on-polyethylene (M-PE), was evaluated using parametric and nonparametric models. RESULTS: After adjustment for patient and clinical factors, and the year of surgery, the mean hospital cost up to 90 days for primary THA with C-PE or COC was within ±1% of the cost for primary THA with M-PE bearings (P < .001). From the nonparametric analysis, the median total hospital cost was US$296-US$353 more for C-PE and COC than M-PE. Cost differentials were found to decrease significantly over time (P < .001). CONCLUSION: Patient and clinical factors had a far greater impact on the total cost of inpatient THA surgery than bearing selection, even when including readmission costs up to 90 days after discharge. Our findings indicate that the cost-effectiveness thresholds for ceramic bearings relative to M-PE are changing over time and increasingly achievable for the Medicare population.

Polymethyl Methacrylate in Patient-Specific Implants: Description of a New Three-Dimension Technique.

Polymethyl methacrylate (PMMA), an easily moldable and economical synthetic resin, has been used since the 1940s. In addition, PMMA has good mechanical properties and is one of the most biocompatible alloplastic materials currently available. The PMMA can serve as a spacer and as a delivery vehicle for antibiotics. Prior studies have indicated that no significant differences in infection rates exist between autologous and acrylic cranioplasty. Although inexpensive, the free-hand cranioplasty technique often yields unsatisfactory cosmetic results. In the present study, the application of a recently developed, economic modality for the perioperative application, and molding of PMMA to ensure a precise fit in 16 patients using computer-aided design, computer-aided manufacturing, and rapid prototyping was described.The mean defect size was 102.0 ±â€Š26.4 cm. The mean volume of PMMA required to perform the cranioplasty procedure was 51 mL. The cost of PMMA was approximately 6 Euro (&OV0556;) per mL. The costs of fabricating the implants varied from 119.8 &OV0556; to 1632.0 &OV0556; with a mean of 326.4 &OV0556; ±â€Š371.6. None of the implants required removal during the follow-up period.

Cost-comparison of third generation transcatheter aortic valve implantation (TAVI) devices in the German Health Care System.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has a substantial impact on daily cardiovascular care delivery based on issues such as cost effectiveness and economic value within a restricted health care budget. Until now, potential financial benefits of third generation valve models have not been evaluated in a real-world setting. METHODS AND RESULTS: We identified 204 eligible patients (Jan 2014-Sep 2016) who either received the balloon-expandable Edwards Sapien 3 (ES3) or the self-expandable Medtronic Evolut R (MER). Baseline information, procedural characteristics, 30-day outcome as well as in-hospital costs and reimbursement were collected and analyzed. The major cost driver was initial valve-kit costs with a significantly higher amount in the ES3 group, which was set at 0 with the lower price (ES3/MER: +4390.0€â€¯±â€¯3.807.0 vs. 0.0€â€¯±â€¯734.1; p < 0.01). However, initial valve-kit costs were balanced by additional material costs in the MER cohort. Overall costs did not differ significantly between valve models (ES3/MER: x + 13.808.0€â€¯±â€¯5.595.0 vs. x + 10.681.0€â€¯±â€¯4.518.0; p = 0.6885) and reimbursement was moderate (ES3/MER: 1.649.7€ vs. 4776.7€). CONCLUSION: Quality, success rate, and costs were comparable between third generation devices. Initial valve-kit costs were significantly higher in the ES3 group, whereas overall costs did not significantly differ between the two valve types.

Towards Ultra Low-Cost Myoactivated Prostheses.

In developing countries, due to the high cost involved, amputees have limited access to prosthetic limbs. This constitutes a barrier for this people to live a normal life. To break this barrier, we are developing ultra-low-cost closed-loop myoactivated prostheses that are easy to maintain manufacture and that do not require electrodes in contact with the skin to work effectively. In this paper, we present the implementation for a simple but functional hand prosthesis. Our simple design consists of a low-cost embedded microcontroller (Arduino), a wearable stretch sensor (adapted from electroresistive bands normally used for "insulation of gaskets" against EM fields), to detect residual muscle contraction as direct muscle volumetric shifts and a handful of common, not critical electronic components. The physical prosthesis is a 3D printed claw-style two-fingered hand (PLA plastic) directly geared to an inexpensive servomotor. To make our design easier to maintain, the gears and mechanical parts can be crafted from recovered materials. To implement a closed loop, the amount of closure of prosthesis is fed back to the user via a second stretch sensor directly connected to claw under the form of haptic feedback. Our concept design comprised of all the parts has an overall cost below AUD 30 and can be easily scaled up to more complicated devices suitable for other uses, i.e., multiple individual fingers and wrist rotation.

Evaluation of locally manufactured patient-specific custom made implants for cranial defects using a silicone mould.

BACKGROUND: Cranial vault defects can pose a significant problem for neurosurgeons where autologous bone is no longer available for cranioplasty. Numerous materials exist to create implants which include polymethyl methacrylate (PMMA) and titanium. A technique using 3-dimensional CT scan reconstruction of a cranial defect and creating a silicon mould which can be autoclaved in theatre to create a PMMA implant was developed. OBJECTIVE: The aim of this study is to evaluate the efficacy, cosmetic result, safety and cost-effectiveness of this procedure and compare this to existing techniques. METHOD: An ambispective study was performed in patients requiring cranioplasty with a custom made implant. Patients were assessed for risk factors and cosmetic outcome, surgical technique was described and complications and cost compared to existing literature between 2010 and 2016. RESULTS: Thirty retrospective and 30 consecutive prospective patients were recruited into the study. Overall sepsis rate was 8.3%. All septic cases had superficial sepsis of which 2 grafts were removed due to cerebrospinal fluid leakage resulting in wound breakdown. A 100% accurate implant to defect ratio was achieved leading to a high satisfaction rate. Average cost was 5 times cheaper than the closest market related product. CONCLUSION: Patient specific moulds using PMMA to create custom implants are safe, have excellent cosmetic results and are a very cost-effective option to manage cranial defects. Accurate planning strategies for large craniotomies, where bone will potentially be discarded, add to surgical effectiveness and cost-saving to the patient.

When Would a Metal-Backed Component Become Cost-Effective Over an All-Polyethylene Tibia in Total Knee Arthroplasty?

The importance of cost control in total knee arthroplasty is increasing in the United States secondary to both changing economic realities of healthcare and the increasing prevalence of joint replacement. Surgeons play a critical role in cost containment and may soon be incentivized to make cost-effective decisions under proposed gainsharing programs. The purpose of this study is to examine the cost-effectiveness of all-polyethylene tibial (APT) components and determine what difference in revision rate would make modular metal-backed tibial (MBT) implants a more cost-effective intervention. Markov models were constructed using variable implant failure rates and previously published probabilities. Cost data were obtained from both our institution and published United States implant list prices, and modeled with a 3.0% discount rate. The decision tree was continued over a 20-year timeframe. Using our institutional cost data and model assumptions with a 1.0% annual failure rate for MBT components, an annual failure rate of 1.6% for APT components would be required to achieve equivalency in cost. Over a 20-year period, a failure rate of >27% for the APT component would be necessary to achieve equivalent cost compared with the proposed failure rate of 18% with MBT components. A sensitivity analysis was performed with different assumptions for MBT annual failure rates. Given our assumptions, the APT component is cost-saving if the excess cumulative revision rate increases by <9% in 20 years compared with that of the MBT implant. Surgeons, payers, and hospitals should consider this approach when evaluating implants. Consideration should also be given to the decreased utility associated with revision surgery.