Project description:Running-specific prostheses (RSPs) have facilitated an athlete with bilateral transtibial amputations to compete in the Olympic Games. However, the performance effects of using RSPs compared to biological legs remains controversial. Further, the use of different prosthetic configurations such as shape, stiffness, and height likely influence performance. We determined the effects of using 15 different RSP configurations on the maximum speed of five male athletes with bilateral transtibial amputations. These athletes performed sets of running trials up to maximum speed using three different RSP models (Freedom Innovations Catapult FX6, Össur Flex-Foot Cheetah Xtend and Ottobock 1E90 Sprinter) each with five combinations of stiffness category and height. We measured ground reaction forces during each maximum speed trial to determine the biomechanical parameters associated with different RSP configurations and maximum sprinting speeds. Use of the J-shaped Cheetah Xtend and 1E90 Sprinter RSPs resulted in 8.3% and 8.0% (p<0.001) faster maximum speeds compared to the use of the C-shaped Catapult FX6 RSPs, respectively. Neither RSP stiffness expressed as a category (p = 0.836) nor as kN·m-1 (p = 0.916) affected maximum speed. Further, prosthetic height had no effect on maximum speed (p = 0.762). Faster maximum speeds were associated with reduced ground contact time, aerial time, and overall leg stiffness, as well as with greater stance-average vertical ground reaction force, contact length, and vertical stiffness (p = 0.015 for aerial time, p<0.001 for all other variables). RSP shape, but not stiffness or height, influences the maximum speed of athletes with bilateral transtibial amputations.
Project description:Limited available information describes how running-specific prostheses and running speed affect the biomechanics of athletes with bilateral transtibial amputations. Accordingly, we quantified the effects of prosthetic stiffness, height and speed on the biomechanics of five athletes with bilateral transtibial amputations during treadmill running. Each athlete performed a set of running trials with 15 different prosthetic model, stiffness and height combinations. Each set of trials began with the athlete running on a force-measuring treadmill at 3 m s-1, subsequent trials incremented by 1 m s-1 until they achieved their fastest attainable speed. We collected ground reaction forces (GRFs) during each trial. Prosthetic stiffness, height and running speed each affected biomechanics. Specifically, with stiffer prostheses, athletes exhibited greater peak and stance average vertical GRFs (β = 0.03; p < 0.001), increased overall leg stiffness (β = 0.21; p < 0.001), decreased ground contact time (β = -0.07; p < 0.001) and increased step frequency (β = 0.042; p < 0.001). Prosthetic height inversely associated with step frequency (β = -0.021; p < 0.001). Running speed inversely associated with leg stiffness (β = -0.58; p < 0.001). Moreover, at faster running speeds, the effect of prosthetic stiffness and height on biomechanics was mitigated and unchanged, respectively. Thus, prosthetic stiffness, but not height, likely influences distance running performance more than sprinting performance for athletes with bilateral transtibial amputations.
Project description:AimsThe primary objective of this study was to compare the postoperative infection rate between negative pressure wound therapy (NPWT) and conventional dressings for closed incisions following soft-tissue sarcoma (STS) surgery. Secondary objectives were to compare rates of adverse wound events and functional scores.MethodsIn this prospective, single-centre, randomized controlled trial (RCT), patients were randomized to either NPWT or conventional sterile occlusive dressings. A total of 17 patients, with a mean age of 54 years (21 to 81), were successfully recruited and none were lost to follow-up. Wound reviews were undertaken to identify any surgical site infection (SSI) or adverse wound events within 30 days. The Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) score were recorded as patient-reported outcome measures (PROMs).ResultsThere were two out of seven patients in the control group (28.6%), and two out of ten patients in the intervention group (20%) who were diagnosed with a SSI (p > 0.999), while one additional adverse wound event was identified in the control group (p = 0.593). No significant differences in PROMs were identified between the groups at either 30 days (TESS, p = 0.987; MSTS, p = 0.951) or six-month (TESS, p = 0.400) follow-up. However, neoadjuvant radiotherapy was significantly associated with a SSI within 30 days of surgery, across all patients (p = 0.029). The mean preoperative modified Glasgow Prognostic Score (mGPS) was also significantly higher among patients who developed a postoperative adverse wound event (p = 0.028), including a SSI (p = 0.008), across both groups.ConclusionThis is the first RCT comparing NPWT with conventional dressings following musculoskeletal tumour surgery. Postoperative wound complications are common in this group of patients and we observed an overall SSI rate of 23.5%. We propose proceeding to a multicentre trial, which will help more clearly define the role of closed incision NPWT in STS surgery. Cite this article: Bone Jt Open 2021;2(12):1049-1056.
Project description:Soft robot has been one significant study in recent decades and soft gripper is one of the popular research directions of soft robot. In a static gripping system, excessive gripping force and large deformation are the main reasons for damage of the object during the gripping process. For achieving low-damage gripping to the object in static gripping system, we proposed a soft-rigid gripper actuated by a linear-extension soft pneumatic actuator in this study. The characteristic of the gripper under a no loading state was measured. When the pressure was >70 kPa, there was an approximately linear relation between the pressure and extension length of the soft actuator. To achieve gripping force and fingertip displacement control of the gripper without sensors integrated on the finger, we presented a non-contact sensing method for gripping state estimation. To analyze the gripping force and fingertip displacement, the relationship between the pressure and extension length of the soft actuator in loading state was compared with the relationship under a no-loading state. The experimental results showed that the relative error between the analytical gripping force and the measured gripping force of the gripper was ≤2.1%. The relative error between analytical fingertip displacement and theoretical fingertip displacement of the gripper was ≤7.4%. Furthermore, the low damage gripping to fragile and soft objects in static and dynamic gripping tests showed good performance of the gripper. Overall, the results indicated the potential application of the gripper in pick-and-place operations.
Project description:BackgroundTraumatic arm amputations can be treated with replantation or surgical formalization of the stump with or without subsequent prosthetic fitting. In the literature, many authors suggest the superiority of replantation. This systematic review compared available literature to analyze whether replantation is functionally and psychologically more profitable than formalization and prosthetic fitting in patients with traumatic arm amputation.MethodsFunctional outcome and satisfaction levels were recorded of patients with amputation levels below elbow, through elbow, and above elbow.ResultsFunctional outcomes of 301 replantation patients and 172 prosthesis patients were obtained. In the replantation group, good or excellent functional scores were reported in 39% of above elbow, 55% of through elbow, and 50% of below elbow amputation cases. Nearly 100% of patients were satisfied with the replanted limb. In the prosthesis group, full use of the prosthesis was attained in 48% of above elbow and in 89% of below elbow amputation patients. Here, 29% of patients elected not to use the prosthesis for reasons including pain and functional superfluity. In both replantation patients and prosthesis wearers, a below elbow amputation yielded better functional results than higher amputation levels.ConclusionsReplantation of a traumatically amputated arm leads to good function and higher satisfaction rates than a prosthesis, regardless of the objective functional outcome. Sensation and psychological well-being seem the two major advantages of replantation over a prosthesis. The current review of the available literature shows that in carefully selected cases replantation could be the preferred option of treatment.
Project description:This study assesses the cost-effectiveness of Technology Lipido-Colloid with Nano Oligo Saccharide Factor (TLC-NOSF) wound dressings versus neutral dressings in the management of diabetic foot ulcers (DFUs) from a French collective perspective. We used a Markov microsimulation cohort model to simulate the DFU monthly progression over the lifetime horizon. Our study employed a mixed method design with model inputs including data from interventional and observational studies, French databases and expert opinion. The demographic characteristics of the simulated population and clinical efficacy were based on the EXPLORER double-blind randomized controlled trial. Health-related quality of life, costs, and resource use inputs were taken from the literature relevant to the French context. The main outcomes included life-years without DFU (LYsw/DFU), quality-adjusted life-years (QALYs), amputations, and lifetime costs. To assess the robustness of the results, sensitivity and subgroup analyses based on the wound duration at treatment initiation were performed. Treatment with the TLC-NOSF dressing led to total cost savings per patient of EUR 35,489, associated with gains of 0.50 LYw/DFU and 0.16 QALY. TLC-NOSF dressings were established as the dominant strategy in the base case and all sensitivity analyses. Furthermore, the model revealed that, for every 100 patients treated with TLC-NOSF dressings, two amputations could be avoided. According to the subgroup analysis results, the sooner the TLC-NOSF treatment was initiated, the better were the outcomes, with the highest benefits for ulcers with a duration of two months or less (+0.65 LYw/DFU, +0.23 QALY, and cost savings of EUR 55,710). The results from the French perspective are consistent with the ones from the German and British perspectives. TLC-NOSF dressings are cost-saving compared to neutral dressings, leading to an increase in patients' health benefits and a decrease in the associated treatment costs. These results can thus be used to guide healthcare decisionmakers. The potential savings could represent EUR 3,345 per treated patient per year and even reach EUR 4,771 when TLC-NOSF dressings are used as first line treatment. The EXPLORER trial is registered with ClinicalTrials.gov, number NCT01717183.
Project description:Improved biomechanical and clinical outcomes are seen when the femoral tunnels of the anterior cruciate ligament (ACL) are placed in the center of the femoral insertion. The transtibial (TT) technique has been shown to be less capable of this than an anteromedial (AM) portal approach but is more familiar to surgeons and less technically challenging. A hybrid transtibial (HTT) technique using medial portal guidance of a transtibial guide wire without knee hyperflexion may offer anatomic tunnel placement while maintaining the relative ease of a TT technique.To evaluate the anatomic and biomechanical performance of the HTT technique compared with TT and AM approaches.Controlled laboratory study.Thirty-six paired, fresh-frozen human knees were used. Twenty-four knees (12 pairs) underwent all 3 techniques (TT, AM, HTT) for femoral tunnel placement, with direct measurement of femoral insertional overlap and femoral tunnel length. The remaining 12 knees (6 pairs) underwent completed reconstructions to evaluate graft anisometry and tunnel orientation, with each technique performed in 4 specimens and tested using motion sensors with a quad-load induced model. Graft length changes and graft/femoral tunnel angle were measured at varying degrees of flexion.Percentage overlap of the femoral insertion averaged 37.0% ± 28.6% for TT, 93.9% ± 5.6% for HTT, and 79.7% ± 7.7% for AM, with HTT significantly greater than both TT (P = .007) and AM (P = .001) approaches. Graft length change during knee flexion (anisometry) was 30.1% for HTT, 12.8% for AM, and 8.5% for TT. When compared with the TT approach, HTT constructs exhibited comparable graft-femoral tunnel angulation (TT, 150° ± 3° vs HTT, 142° ± 2.3°; P < .001) and length (TT, 42.6 ± 2.8 mm vs HTT, 38.5 ± 2.0 mm; P = .12), while AM portal tunnels were significantly shorter (31.6 ± 1.6 mm; P = .001) and more angulated (121° ± 6.5°; P < .001).The HTT technique avoids hyperflexion and maintains femoral tunnel orientation and length, similar to the TT technique, but simultaneously achieves anatomic graft positioning.The HTT technique offers an anatomic alternative to an AM portal approach while maintaining the technical advantages of a traditional TT reconstruction.
Project description:ObjectiveTo determine the effect of a keratin dressing for treating slow-to-heal venous leg ulcers (VLU) on VLU healing.DesignPragmatic parallel group randomised controlled trial.SettingCommunity-dwelling participants.ParticipantsPeople aged 18 or more years with VLU (either present for more than 26 weeks or ulcer area larger than 5 cm2 or both).InterventionWool-derived keratin dressing or usual care formulary of non-medicated dressings, on a background treatment with compression.Primary and secondary outcome measuresHealing at 24 weeks based on blinded assessment of ulcer photographs. Other outcomes included time to complete healing, change in ulcer area to 24 weeks, change in health-related quality of life and incidence of adverse events.ResultsWe screened 1068 patients with VLU and randomised 143 participants (51.1% of target recruitment), 71 to the keratin dressing group and 72 to the usual care group.The mean age was 66.1 years (SD 15.9) and 53 participants (37.1%) were women. There were no significant differences between the groups on the primary outcome (risk difference -6.4%, 95% CI -22.5% to 9.7%), change in ulcer area (-1.9 cm2, 95% CI -16.5 to 12.8 cm2), time to complete healing (HR 0.80, 95% CI 0.52 to 1.23) or the incidence of adverse events (incidence rate ratio 1.19, 95% CI 0.89 to 1.59) in the intention-to-treat analyses. However, the direction of effect on the primary outcome was reversed in a per protocol analysis specified a priori (risk difference 6.2%, 95% CI -12.4% to 24.9%).ConclusionThe effect of adding a keratin dressing to the treatment regimen for prognostically slow-to-heal VLU remains unclear.Trial registration numberNCT02896725.
Project description:The aim of our study was to determine military-specific outcomes for transtibial amputations of US Service members using either the traditional technique (Burgess) or the Ertl technique. All US Service members sustaining transtibial, combat-related amputation from September 2001 through July 2011 were reviewed. Amputation type, mechanism of injury, time interval to amputation, age, sex, branch of service, rank, force, nature, and injury severity score were recorded. Outcomes were determined by analyzing military-specific medical review results, to include the following: Physical Evaluation Board Liaison Office (PEBLO) rating (0-100), PEBLO outcome (permanent retirement, temporary disability retirement, separation without benefits, continuation of active duty, or fit for redeployment), and the rate of redeployment. Amputation type (Ertl vs. Burgess) was determined by reviewing postoperative radiographs and radiology reports. Data from all of the above categories were compared for both Ertl and Burgess amputees. Of 512 subjects identified, 478 had radiographs or radiology reports distinguishing between Ertl or Burgess transtibial amputation. A total of 406 subjects underwent the Burgess procedure, and 72 subjects underwent the Ertl procedure. There was not a significant difference between the two groups in review board rating (p = 0.858), review board outcome (p = 0.102), or ability to deploy (p = 0.106); however, subjects that underwent the Ertl procedure remained on active duty at a significantly higher rate (p = 0.021). There is a higher rate of remaining on active duty using the Ertl technique. This study suggests that there is an improvement in functional outcome with the Ertl technique.
Project description:Soft clay-like Li-superionic conductors, integral to realizing all-solid-state batteries, have been recently synthesized by mixing rigid-salts. Here, through computational and experimental analysis, we clarify how a soft clay-like material can be created from a mixture of rigid-salts. Using molecular dynamics simulations with a deep learning-based interatomic potential energy model, we uncover the microscopic features responsible for soft clay-formation from ionic solid mixtures. We find that salt mixtures capable of forming molecular solid units on anion exchange, along with the slow kinetics of such reactions, are key to soft-clay formation. Molecular solid units serve as sites for shear transformation zones, and their inherent softness enables plasticity at low stress. Extended X-ray absorption fine structure spectroscopy confirms the formation of molecular solid units. A general strategy for creating soft clay-like materials from ionic solid mixtures is formulated.