Measuring Patient Preferences at the FDA Center for Devices and Radiological Health: Reflections and Projections.

OBJECTIVES: Patient preference information (PPI) is a way to incorporate the patient voice in the evaluation of medical devices. The US Food and Drug Administration (FDA) Center for Devices and Radiological Health (CDRH) has been working to encourage the voluntary inclusion of PPI throughout the medical device lifecycle for nearly a decade. This article reflects CDRH's efforts to encourage collection of PPI and offers perspectives on the future of PPI in the evaluation of medical devices. METHODS: CDRH regulatory guidance, public meetings, and collaborations relating to PPI were explored. RESULTS: Since 2012 when CDRH issued guidance on how PPI can be used as scientific evidence in the benefit-risk regulatory submission, CDRH has issued 5 subsequent guidance documents expanding on the use of PPI in medical device evaluations. CDRH remains committed to advancing the science and application of PPI in the medical device ecosystem through many collaborations with professional organizations, patient advocacy groups, and academic institutions. By hosting and actively participating in multiple scientific and regulatory public meetings and conferences, CDRH fosters a continuous learning environment where the experience of using PPI in regulatory submissions can be shared. A September 2020 meeting cosponsored by FDA and International Society for Pharmacoeconomics and Outcomes Research (ISPOR) discussed the state of PPI in regulatory applications and beyond. CONCLUSION: This article describes these pivotal events that have helped to increase the use of PPI in medical device evaluation as well as discusses future applications of PPI.

Assessment of Upper Extremity Function.

Assessment of upper extremity function either before or after surgical treatment has been a rapidly evolving field. A reproducible, accurate, and valid assessment tool provides the ability to compare surgical interventions, evaluate physical therapy regimens, and assess novel assistive and restorative technologies. The purpose of this article is to detail the various upper extremity assessment tools and introduce the concept of real-world data acquisition of upper extremity function.

Integrating Patient-Generated Health Data Throughout the Total Product Life Cycle of Medical Devices.

Nearly ubiquitous use of personal electronics, wearable sensors, and other types of digital health technologies, along with wireless connectivity, makes the capture of health data directly from an individual easier, enabling the use of patient-generated health data (PGHD) as a potential bridge between a patient's home and the healthcare system. This type of real-world data may be a completely new type of information, or it may be a more frequent collection of traditional information over longer time periods to form a longitudinal view of a patient's health status that can inform decision-making in clinical, medical product regulatory, and coverage and reimbursement settings. The U.S. Food and Drug Administration's Center for Devices and Radiological Health (CDRH) has been exploring and advancing the collection and use of PGHD since 2016, hosting a public meeting on the topic in May 2021. This manuscript presents highlights from various discussions at this meeting including those on the importance of stakeholder engagement, characteristics of high data quality, and PGHD in practice in patient-driven registries, as well as a look forward to some of the opportunities in the field.

Upper extremity function in the free living environment of adults with traumatic brachial plexus injuries.

Transition of data acquisition out of the laboratory, into the real world offers a previously inaccessible perspective of physical function. This proves to be beneficial when assessing surgical intervention, especially after a traumatic brachial plexus injury (BPI) causing loss of motor function in an upper extremity (UE). Moving towards the use of real world data in clinical practice as an outcome measure, this study developed a method to report bilateral UE activity in patients with BPI. Three groups of ten subjects each participated in this study-healthy controls, subjects with traumatic BPI prior to surgical treatment (pre-), and subjects who had surgical reconstruction to treat BPI (post-). Subjects wore four activity monitors on bilateral forearms and upper arms for four days. Tri-axial acceleration data were used to calculate asymmetry indices for forearm and upper arm usage. Analysis revealed a bimodal distribution in the post- group, prompting division of this group into two subgroups based on injury type: pan-plexus and upper trunk. While median asymmetry indices at the forearm and upper arm were decreased in the post- group when compared to the pre- group, these differences were not significant. Compared to controls, the pre-surgery group (p < 0.0001, p < 0.0001) and post-surgery group with pan-plexus injuries (p = 0.0074, p = 0.0242) both exhibited statistically significant differences in forearm and upper arm asymmetry, respectively. Further investigation to establish clinically significant differences in asymmetry index is warranted. Importantly, analyzing the activity of UEs following treatment of a BPI provides objective real world evidence of function.

Patient-reported outcomes and medical device evaluation: from conception to implementation.

BACKGROUND: The insights gleaned from patient-reported outcomes (PROs) have implications across the healthcare ecosystem, from clinical investigations to evaluate the safety and effectiveness of medical devices to clinical care and reimbursement decisions. The U.S. Food and Drug Administration's (FDA) Center for Devices and Radiological Health (CDRH) hosted a public meeting in September 2020 discussing how PROs can be used in medical device evaluation throughout the total product life cycle, as well as methods for developing and modifying PRO instruments to ensure they are fit-for-purpose. This commentary presents key points of discussion from the meeting, providing insight into the increased interest in PRO data to support medical product development while also exploring future opportunities of incorporating PRO data throughout healthcare. MAIN BODY: Thoughtful use of fit-for-purpose PRO instruments to integrate the patient's voice into clinical care paradigms, medical device development, regulatory decisions, and reimbursement and coverage decisions were emphasized throughout the meeting. Existing PRO instruments may be used if the context of use is appropriate. Modifications to an existing PRO instrument may also be explored to ensure the instrument is fit-for-purpose in a new context of use. Development of a novel PRO instrument may be necessary to capture attributes in a new patient population or application. Multi-stakeholder collaborations, of which patients are a key component, create efficiencies in the development and modification of PRO instruments. CONCLUSION: Continued multi-stakeholder collaborations bringing together researchers, clinicians, patients, regulators, and payers are critical to further advance the inclusion of the patient voice incorporating PRO instruments throughout the healthcare ecosystem in an efficient manner that is least burdensome to patients.

Inclusion of patient-reported outcome instruments in US FDA medical device marketing authorizations.

BACKGROUND: The U.S. Food and Drug Administration encourages the incorporation of the patient voice throughout the medical device total product lifecycle. This study examined the incorporation of patient-reported outcome (PRO) instruments in the evaluation of medical devices over a six-year period. PRO instruments used to inform study endpoints were extracted from the summary documents and clinical trial data of premarket authorizations posted on publicly available FDA databases between October 1, 2014-September 30, 2020. RESULTS: PROs were included in 53% of authorizations, with 34% using PROs as primary and secondary endpoints. This study found that PRO instruments were used in each type of marketing authorization and in all medical specialties examined in this study. CONCLUSIONS: Expanding the current collaborative efforts to develop and modify PRO instruments may help to improve use of PROs in medical device evaluations.

Application of a myoelectric elbow flexion assist orthosis in adult traumatic brachial plexus injury: patient perspectives.

BACKGROUND: Individuals with brachial plexus injuries (BPIs) can be prescribed assistive devices, including myoelectric elbow orthoses (MEOs), for rehabilitation or functional use after failed treatment for elbow flexion restoration. Although recent case studies indicate potential for clinical improvements after using an MEO after BPI, the patients' perspectives on such use are still unknown. OBJECTIVE: To explore patient perspectives on the use of an MEO after surgical treatment for a traumatic BPI. STUDY DESIGN: Qualitative using both a focus group and semistructured interviews. METHODS: Patients with BPI that used an MEO were recruited. Five patients participated in an in-person focus group, whereas three patients participated in individual phone interviews. Themes that emerged from the focus group were compared against those that emerged from the personal interviews. RESULTS: Feedback was grouped into three themes: device usage, hardware performance, and device design. Within each theme, positive elements, areas for improvement, and additional considerations emerged. Patients indicated a positive attitude toward using an MEO as a rehabilitation tool. They desired a streamlined, stronger device to support them and assist during activities of daily living. CONCLUSIONS: For patients with BPI, a well-designed MEO that meets their needs could assist with rehabilitation and increase independence in daily activities. Continued patient engagement in the evaluation and development of both medical devices and treatment plans offers the best opportunity for improved outcomes that are important to the patient.

Effects of elbow immobilization on upper extremity activity.

BACKGROUND: It has been dogma that handedness greatly impacts daily activities. Interruptions in the ability to utilize the dominant arm due to neuromusculoskeletal injuries could negatively impact performance of activities of daily living. Daily activity can be measured using activity monitors. This study aimed to examine how arm dominance impacts function by immobilizing the arms of healthy individuals. METHODS: Ten individuals wore four upper extremity activity monitors for three days-one day without immobilization, one day with their dominant arm immobilized, and one day with their non-dominant arm immobilized. Triaxial acceleration data was used to calculate average daily activity and an asymmetry index. Between-condition differences were examined. FINDINGS: During dominant arm immobilization, the dominant forearm had significantly less average daily activity when compared to the no immobilization day (p = .0001) and the non-dominant immobilized day (p < .0001). A similar trend was observed at the non-dominant forearm when the non-dominant arm was immobilized. Immobilization of an arm increased asymmetry index and reliance on the non-immobilized arm. Significant differences in asymmetry index were not observed between the two casted conditions. INTERPRETATION: When an upper extremity was casted, immobilized forearm and upper arm average daily activity was comparable. Dominance did not have an effect on asymmetry index. Immobilization affected asymmetry index compared to no immobilization. This study has demonstrated that regardless of arm immobilized, there will be a reliance on the contralateral limb about twice as much as the immobilized limb. This could prove problematic if the contralateral limb is restricted or injured, limiting independent.

Developing Strategies for Sustainable Medical Equipment Maintenance in Under-Resourced Settings.

Engineering technology plays a pivotal role in the delivery of health care in under-resourced countries by providing an infrastructure to improve patient outcomes. However, sustainability of these technologies is difficult in these settings oftentimes due to limited resources or training. The framework presented in this editorial focuses on establishing medical and laboratory equipment sustainability in developing countries and is comprised of four steps: 1) establishing reliable in-country relationships with stakeholders, 2) identifying needs for sustainable solutions locally, 3) exploring potential solutions and assessing their effort-to-impact ratios, and 4) working with strategic partners to implement solutions with clear performance metrics. By focusing on the sustainability of donated equipment instead of the equipment itself, this method presented distinguishes itself from other philanthropic endeavors in the field by seeking to establish preventive maintenance habits that can impact clinical outcomes of a community long term. Application of this methodology is reported in the Original Research Article "A Low-Cost Humidity Control System to Protect Microscopes in a Tropical Climate" by Asp et. al.

A Low-Cost Humidity Control System to Protect Microscopes in a Tropical Climate.

Introduction: A clean and functional microscope is necessary for accurate diagnosis of infectious diseases. In tropical climates, high humidity levels and improper storage conditions allow for the accumulation of debris and fungus on the optical components of diagnostic equipment, such as microscopes. Objective: Our objective was to develop and implement a low-cost, sustainable, easy to manage, low-maintenance, passive humidity control chamber to both reduce debris accumulation and microbial growth onto the optical components of microscopes. Methods: Constructed from easily-sourced and locally available materials, the cost of each humidity control chamber is approximately $2.35 USD. Relative humidity levels were recorded every 30 minutes over a period of 10 weeks from two chambers deployed at the Belize Vector and Ecology Center and the University of Belize. Results: The humidity control chamber deployed at the University of Belize maintained internal relative humidity at an average of 35.3% (SD = 4.2%) over 10 weeks, while the average external relative humidity was 86.4% (SD = 12.4%). The humidity control chamber deployed at the Belize Vector and Ecology Center effectively maintained internal relative humidity to an average of 54.5% (SD = 9.4%) over 10 weeks, while the average external relative humidity was 86.9% (SD = 12.9%). Conclusions: Control of relative humidity is paramount for the sustainability of medical equipment in tropical climates. The humidity control chambers reduced relative humidity to levels that were not conducive for fungal growth while reducing microscope contamination from external sources. This will likely extend the service life of the microscopes while taking advantage of low-cost, locally sourced components.

Kinematic profiles during activities of daily living in adults with traumatic brachial plexus injuries.

BACKGROUND: Injuries to the brachial plexus leave individuals with lasting effects in upper extremity motor function, even with successful surgical restoration of elbow flexion. Quantitatively describing independent patient function during activities of daily living utilizing motion analysis could aid in prioritization of secondary surgical targets, as well as serve as an outcome measure. This study explored the upper extremity kinematic profiles during activities of daily living in adults with brachial plexus injury. METHODS: Eight adult participants (4 subjects with brachial plexus injury, 4 healthy controls) completed activities of daily living during one motion capture setting. Trunk, shoulder, and elbow joint minima, maxima, and range of motion were calculated and compared between groups. Kinematic profiles over a motion cycle were compared between groups using statistical parametric mapping. FINDINGS: Subjects with brachial plexus injuries had significantly greater trunk range of motion during feeding and dressing tasks compared to control subjects. This compensatory trunk motion was accompanied by limited shoulder external rotation demonstrated using conventional descriptors and statistical parametric mapping. INTERPRETATION: Significant compensatory trunk motion is required to complete select activities of daily living in subjects with brachial plexus injury. Additionally, restoration of shoulder external rotation would be a beneficial secondary target of surgical restoration of motor function. These aspects should be considered in treatment planning, as they could impact patient outcomes. Combining conventional descriptors of patient motion (e.g. joint minima, maxima, and range of motion) with statistical parametric mapping can provide a rich description of patient compensations and limitations.

Instantaneous stiffness and hysteresis of dynamic elastic response prosthetic feet.

BACKGROUND: Dynamic elastic response prosthetic feet are designed to mimic the functional characteristics of the native foot/ankle joint. Numerous designs of dynamic elastic response feet exist which make the prescription process difficult, especially because of the lack of empirical evidence describing the objective performance characteristics of the feet. OBJECTIVES: To quantify the mechanical properties of available dynamic elastic response prosthetic feet, specifically the stiffness and hysteresis. STUDY DESIGN: Mechanical testing of dynamic elastic response prosthetic feet. METHODS: Static Proof Testing in accordance with ISO 10328 was conducted on seven dynamic elastic response prosthetic feet. Load-displacement data were used to calculate the instantaneous stiffness in both the heel and forefoot regions, as well as hysteresis associated with each foot. RESULTS: Heel stiffness was greater than forefoot stiffness for all feet. The heel of the glass composite prosthetic foot was stiffer than the carbon fiber feet and it exhibited less hysteresis. Two different carbon fiber feet had the stiffest forefoot regions. CONCLUSION: Mechanical testing is a reproducible method that can be used to provide objective evidence about dynamic elastic response prosthetic foot performance and aid in the prescription process. Clinical relevance The quantitative stiffness and hysteresis data from this study can be used by prosthetists to aid the prescription process and make it more objective.

Design of a novel prosthetic socket: assessment of the thermal performance.

Prosthetic liners and sockets insulate the residual limb, causing excessive sweating and concomitant skin maceration. When coupled with atypical loading conditions, further dermatologic problems can arise. This can significantly reduce the quality of life of an amputee patient. Improving the design of the prosthetic socket has been proposed as a means of reestablishing a normal thermal environment around the residual limb. In this study, a prosthetic socket was modified by incorporating a helical cooling channel within the socket wall using additive manufacturing techniques. Two sockets were modeled: a control socket, and a modified socket containing a 0.48 cm diameter cooling channel. Computer simulations and bench-top testing were used to assess the design's ability to create a greater temperature differential across the socket wall. A greater temperature drop across the socket wall suggested that the socket could provide cooling benefits to the residual limb by allowing for heat to be drawn away from the limb. The temperature difference across the socket wall was calculated for both sockets in each aspect of the study. Both socket type (p=0.002) and location on the socket (p=0.014) were statistically significant factors affecting the temperature difference between inner and outer socket walls. Compared with the control socket, the modified socket containing a helical cooling channel exhibited greater temperature differences across its wall of 11.1 °C and 6.4 °C in the computer simulations and bench-top testing, respectively. This finding suggested that socket modifications, such as the cooling channel presented, could provide a beneficial cooling effect to an amputee patient's residual limb.