Perceptions of primary and secondary care clinicians treating diabetic foot: A pan India study and quantitative analysis.

AIM: The study quantifies clinicians' perceptions and challenges during different stages of diabetic foot treatment. Diabetic neuropathy (DN), which is a major consequence of diabetes, significantly increases the risk of lower limb amputation. This can be prevented to a large extent by foot care, early detection, and lesion treatment. METHODS: Ninety-two Indian clinicians of various demographics, medical specializations, and experiences were interviewed. Diabetic foot treatment by primary and secondary care clinicians was assessed. This study evaluates aspects related to patient awareness, compliance, and shortcomings of current diagnostic techniques. RESULTS: A two-sample Mann-Whitney statistical method was used to infer the perceptions of clinicians on hypothesis questions. Primary and secondary care clinicians' perceptions differed for the hypotheses related to objective assessment (p-value = 0.001), operator variability (p-value = 0.03), and patient compliance (p-value = 0.047). Conversely, both groups held comparative perspectives for the awareness (p-value = 0.369) and examination time (p-value = 0.276) hypotheses. CONCLUSIONS: All clinicians strongly supported the need for an objective assessment to reduce the misdiagnosis of DN. Further, DNis often underdiagnosed due to a lack of awareness and knowledgeamong people with diabetes. Secondary care clinicians acknowledged a need for trained operators to reduce reliability errors. These insights provide directions for future research in this field.

Design, Analysis and Experimental Validation of a Novel 7-Degrees of Freedom Instrument for Laparoscopic Surgeries.

Laparoscopic surgery is widely used for treating intra-abdominal conditions involving the gallbladder, pancreas, liver, intestines and reproductive organs. Conventional laparoscopy instruments used in manual surgeries usually have straight shafts and four degrees of freedom (DOF) plus grasping. However, these are insufficient for the complete rotation of the instrument tip. This makes it challenging to access difficult-to-reach organs inside the abdomen during the surgeries. A few robotic instruments available in the market have higher maneuverability but are expensive. Instruments incorporating cable-based mechanisms require replacement after a few sterilization cycles. This paper describes a novel, reusable and affordable multi-DOF laparoscopy instrument that provides two additional DOF: (a) wrist articulation about one axis (wristed yaw) and (b) rotation of the jaw after articulation (jaw roll). The wrist can articulate up to 45° and also roll after articulation. The additional degrees of freedom enable better maneuverability, functionality and reach than conventional laparoscopy instruments. Further, the new instrument employs only rigid links, providing better strength and minimal loss of function after multiple sterilizations. The complete design of the novel instrument, followed by its kinematic analysis and force calculations are explained in this paper, concluding with its manufacture and experimental validation.

Parameter Optimization for Printing Ti6Al4V-Alloy Patient-Customized Orthopaedic Implants by Laser Powder Bed Fusion Using Physio-mechanical Properties and Biological Evaluations.

Background: A class of additive manufacturing technologies called Laser powder bed fusion (LPBF), which allows fabricating metallic components with complex geometries in near-net-shape, can be employed for fabricating patient-customized orthopaedic implants. Selection and optimization of the LPBF process parameters are critical to achieving the required biomechanical properties and fabricability of such implants. Methods: The process parameters of direct metal laser sintering, the most widely used LPBF process, were optimized for fabricating Ti6Al4V ELI orthopaedic implants, based on ASTM and ASM standards. The parameters included Laser power, Laser velocity and hatch distance, which were varied using Taguchi approach. A multi-criteria decision-making technique (TOPSIS) was employed to optimize the process parameters considering yield and ultimate tensile strength, percentage elongation, part density, volumetric energy density and printing time. In-vitro cytotoxicity and in-vivo muscle implantation were performed on the optimized samples for determining the suitability of the parameters for biomedical applications. Results: A combination of medium laser power, higher laser velocity, and lower hatch distance with values 200 W, 2200 mm/s and 0.08 mm, respectively, was found to be suitable for producing implants. Based on the type of LPBF technology in use, an implant manufacturer can select the initial set of parameters using a similar approach and improve them further based on experimental results. Conclusion: The optimized parameters were found to be suitable for developing orthopaedic implants, in terms of physical, mechanical and biological criteria. The methods and results presented in work are expected to assist the implant manufacturers in meeting the expected user requirements and quality standards.

Surgeon perception of factors affecting the efficiency of conventional and robotic laparoscopy: A Pan India study.

Background: Laparoscopic surgery, being minimally invasive, offers many benefits including faster patient recovery, reduced scarring and lower mortality rate. It is, however, technically challenging and requires a long learning curve. These issues can be overcome by Robot-Assisted Surgery (RAS) systems, which incorporate computer-controlled motions enabling enhanced precision and accuracy. Methods: This study involves identifying and verifying various difficulties related to laparoscopy and the role of RAS in their mitigation. It involved 93 surgeons across India, covering a range of demographics, medical specialties and experience. They were interviewed to understand the current status and to compare RAS with conventional laparoscopy. The questionnaire developed for the purpose tests a set of hypotheses related to instruments, comfort, and other factors derived from the available literature as well as inputs from leading laparoscopy surgeons and domain experts. Results: A grading system was adopted to evaluate the hypotheses based on the surgeons' responses. A statistical method based on T-test was employed to gain useful inferences from the study. The results showed that early-career surgeons preferred haptic enabled systems. As the experience of the surgeon increases, tissue identification becomes easier, thereby reducing the need for haptic feedback-enabled instruments. Conclusions: The surgeons from across the demographics were strongly in the favour of the need for articulated instruments with surgeon-controlled camera systems. They reported a reduction in physical and mental discomfort during surgical procedures using RAS. They also confirmed the similarity in patient outcomes for both conventional laparoscopy and RAS. These insights are expected to be interesting and useful for further research and development in this field.

Development of a functional prototype of a SMART (Sensor-integrated for Monitoring And Remote Tracking) foot abduction brace for clubfoot treatment: a pre-clinical evaluation.

PURPOSE: Recurrences following clubfoot correction by the Ponseti method can be prevented by regular use of a foot abduction brace (FAB) until the child is four to five years old. However, there is a lack of an objective method to measure actual hours of brace usage. The aim was to develop a functional prototype of a SMART (Sensor-integrated for Monitoring And Remote Tracking) clubfoot brace to record accurate brace usage and transmit the data remotely to healthcare providers treating clubfoot. METHODS: A collaborative team of engineers and doctors was formed to investigate various types of sensors and wireless technologies to develop a functional prototype of a SMART brace. RESULTS: Infrared sensors were used to detect if the feet were placed inside the shoes and magnetic Hall effect sensors to detect that the shoes were latched on to the bar of the existing FAB. Brace usage data were captured by the sensors every 15 minutes and stored locally on a data card. A Bluetooth low energy (BLE)-based wireless transmission system was used to send the data daily from the brace to the remote cloud server via a smartphone application. Accurate brace usage data could be recorded by the sensors and visualized in real time on a web-based application in a pre-clinical setting, demonstrating feasibility in clinical practice. CONCLUSION: The low-cost SMART brace prototype that we have developed can accurately measure and remotely transmit brace usage data and has the potential to transform caregivers' behaviour towards brace adherence, which could result in a tangible reduction in recurrence rates.

Parametric Design and Hybrid Fabrication of Above-Knee Prosthesis.

BACKGROUND: India has a large number of above-knee amputation patients who require a prosthetic leg that is affordable, conformal, functional, and durable. Available low-cost solutions, such as Jaipur foot, employ gypsum plaster in the process of fabricating a fitting socket. This has four shortcomings: (1) requirement of trained technicians, (2) high possibility of manual errors leading to rework, (3) long production time of several hours, and (4) difficulty in scaling up for widespread application. MATERIALS AND METHODS: An improved approach is presented here, which combines computer-aided parametric design and numerically controlled machining with manual thermoforming to overcome the above issues. The socket is semi-automatically designed based on 60 parameters, derived from 23 measurements obtained on the natural stump of a patient. The three-dimensional (3D) computer-aided design model of the socket can be used for additive manufacturing (3D printing), which was found to be accurate, but time-consuming and expensive. Hence, a hybrid process was evolved with the following three steps: computer numeric control machining of the stump and shank replica in polyurethane (PU) foam, followed by coating with suitable epoxy, and finally high-density polyethylene pipe thermoforming over the PU foam replicas. RESULTS: Three prostheses were fabricated using both conventional and hybrid processes and provided to volunteer patients. The hybrid process resulted in 28% reduction in overall fabrication time and improved satisfaction of patients due to better fit and comfort. CONCLUSION: The proposed approach can be adapted for mass customization, required to meet the large gap in demand and supply, especially in resource-constrained settings.

Effect of Modularity on the Fatigue Performance of Tibial Tray Designs in TKA Prostheses.

Fatigue performance of tibial tray in total knee arthroplasty (TKA) is of critical importance in terms of longevity of the prosthesis. Standards have been proposed by American Society for Testing and Materials (ASTM) and International Organization for Standardization (ISO) to ensure its long-term structural integrity. The aim of the current study is to evaluate the effect of modularity in the tibial tray following the testing standards, using finite element analysis. Goodman and Sines criteria were used to compare the fatigue safety factor (FSF) of four modular designs versus the two conventional designs. Cruciate-retaining (CR) type modular tibial tray designs were better than posterior-stabilized (PS) type tibial tray designs. More cutouts in the tray and absence of keel were reasons for poor fatigue performance.

Revision of broken knee megaprostheses: new solution to old problems.

BACKGROUND: Low-cost indigenous megaprostheses used in the developing world are prone to mechanical failure but the frequency and causes are not well established. QUESTIONS/PURPOSES: We retrospectively analyzed the causes of failure, particularly design, and suggest changes to reduce the breakage. We also report our experience with revision surgery. METHODS: We identified 28 breakages in 266 megaprosthetic knee arthroplasties performed between January 2000 and December 2006. Twenty-six breakages were revised to another prosthesis. The complications were studied and the function was evaluated. Prostheses were studied for failure by the computer-aided design program SolidWorks(®) and Hyperworks(®) for finite element analysis (FEA). Design improvements were performed based on these results. RESULTS: In 21 cases, the failure occurred at the stem-collar junction, the point of maximum stress predicted by FEA. Stainless steel implants were prone to failure. There was one early and one late infection. Three patients died of metastatic disease. The most difficult surgical step involved the removal of the well-cemented broken stem from the intramedullary canal. Musculoskeletal Tumor Society scores varied from 27 to 29 after revision. FEA revealed stress could be reduced by filleting the stem-collar junction and by two-piece stems. CONCLUSIONS: Revisions of broken total knee megaprostheses, though technically difficult, have allowed patients reasonable function. We recommend design analysis for custom prostheses to point to areas of weakness. Breakages can be reduced by using titanium stems and filleting the junction or by having two-piece inserted stems. Incorporating these changes has reduced the failures in our experience.