Surgery (St Vincent's) - Research Publications
Now showing items 1-12 of 116
A practical 3D-printed soft robotic prosthetic hand with multi-articulating capabilities
(Public Library of Science (PLoS), 2020-05-14)
Soft robotic hands with monolithic structure have shown great potential to be used as prostheses due to their advantages to yield light weight and compact designs as well as its ease of manufacture. However, existing soft prosthetic hands design were often not geared towards addressing some of the practical requirements highlighted in prosthetics research. The gap between the existing designs and the practical requirements significantly hampers the potential to transfer these designs to real-world applications. This work addressed these requirements with the consideration of the trade-off between practicality and performance. These requirements were achieved through exploiting the monolithic 3D printing of soft materials which incorporates membrane enclosed flexure joints in the finger designs, synergy-based thumb motion and cable-driven actuation system in the proposed hand prosthesis. Our systematic design (tentatively named X-Limb) achieves a weight of 253gr, three grasps types (with capability of individual finger movement), power-grip force of 21.5N, finger flexion speed of 1.3sec, a minimum grasping cycles of 45,000 (while maintaining its original functionality) and a bill of material cost of 200 USD (excluding quick disconnect wrist but without factoring in the cost reduction through mass production). A standard Activities Measure for Upper-Limb Amputees benchmark test was carried out to evaluate the capability of X-Limb in performing grasping task required for activities of daily living. The results show that all the practical design requirements are satisfied, and the proposed soft prosthetic hand is able to perform all the real-world grasping tasks of the benchmark tests, showing great potential in improving life quality of individuals with upper limb loss.
Tactile Feedback in Closed-Loop Control of Myoelectric Hand Grasping: Conveying Information of Multiple Sensors Simultaneously via a Single Feedback Channel.
(Frontiers Research Foundation, 2020-04-27)
The appropriate sensory information feedback is important for the success of an object grasping and manipulation task. In many scenarios, the need arises for multiple feedback information to be conveyed to a prosthetic hand user simultaneously. The multiple sets of information may either (1) directly contribute to the performance of the grasping or object manipulation task, such as the feedback of the grasping force, or (2) simply form additional independent set(s) of information. In this paper, the efficacy of simultaneously conveying two independent sets of sensor information (the grasp force and a secondary set of information) through a single channel of feedback stimulation (vibrotactile via bone conduction) to the human user in a prosthetic application is investigated. The performance of the grasping task is not dependent to the second set of information in this study. Subject performance in two tasks: regulating the grasp force and identifying the secondary information, were evaluated when provided with either one corresponding information or both sets of feedback information. Visual feedback is involved in the training stage. The proposed approach is validated on human-subject experiments using a vibrotactile transducer worn on the elbow bony landmark (to realize a non-invasive bone conduction interface) carried out in a virtual reality environment to perform a closed-loop object grasping task. The experimental results show that the performance of the human subjects on either task, whilst perceiving two sets of sensory information, is not inferior to that when receiving only one set of corresponding sensory information, demonstrating the potential of conveying a second set of information through a bone conduction interface in an upper limb prosthetic task.
Concise review: Human articular cartilage repair: Sources and detection of cytotoxicity and genotoxicity in photo-crosslinkable hydrogel bioscaffolds
Three-dimensional biofabrication using photo-crosslinkable hydrogel bioscaffolds has the potential to revolutionize the need for transplants and implants in joints, with articular cartilage being an early target tissue. However, to successfully translate these approaches to clinical practice, several barriers must be overcome. In particular, the photo-crosslinking process may impact on cell viability and DNA integrity, and consequently on chondrogenic differentiation. In this review, we primarily explore the specific sources of cellular cytotoxicity and genotoxicity inherent to the photo-crosslinking reaction, the methods to analyze cell death, cell metabolism, and DNA damage within the bioscaffolds, and the possible strategies to overcome these detrimental effects.
Better Knee, Better Me (TM): effectiveness of two scalable health care interventions supporting self-management for knee osteoarthritis - protocol for a randomized controlled trial
BACKGROUND: Although education, exercise, and weight loss are recommended for management of knee osteoarthritis, the additional benefits of incorporating weight loss strategies into exercise interventions have not been well investigated. The aim of this study is to compare, in a private health insurance setting, the clinical- and cost-effectiveness of a remotely-delivered, evidence- and theory-informed, behaviour change intervention targeting exercise and self-management (Exercise intervention), with the same intervention plus active weight management (Exercise plus weight management intervention), and with an information-only control group for people with knee osteoarthritis who are overweight or obese. METHODS: Three-arm, pragmatic parallel-design randomised controlled trial involving 415 people aged ≥45 and ≤ 80 years, with body mass index ≥28 kg/m2 and < 41 kg/m2 and painful knee osteoarthritis. Recruitment is Australia-wide amongst Medibank private health insurance members. All three groups receive access to a bespoke website containing information about osteoarthritis and self-management. Participants in the Exercise group also receive six consultations with a physiotherapist via videoconferencing over 6 months, including prescription of a strengthening exercise and physical activity program, advice about management, and additional educational resources. The Exercise plus weight management group receive six consultations with a dietitian via videoconferencing over 6 months, which include a very low calorie ketogenic diet with meal replacements and resources to support behaviour change, in addition to the interventions of the Exercise group. Outcomes are measured at baseline, 6 and 12 months. Primary outcomes are self-reported knee pain and physical function at 6 months. Secondary outcomes include weight, physical activity levels, quality of life, global rating of change, satisfaction with care, knee surgery and/or appointments with an orthopaedic surgeon, and willingness to undergo surgery. Additional measures include adherence, adverse events, self-efficacy, and perceived usefulness of intervention components. Cost-effectiveness of each intervention will also be assessed. DISCUSSION: This pragmatic study will determine whether a scalable remotely-delivered service combining weight management with exercise is more effective than a service with exercise alone, and with both compared to an information-only control group. Findings will inform development and implementation of future remotely-delivered services for people with knee osteoarthritis. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12618000930280 (01/06/2018).
Satisfaction after total knee replacement for osteoarthritis is usually high, but what are we measuring? A systematic review
(Elsevier BV, 2020-03)
Objective: Patient satisfaction is considered an important outcome measure after total knee replacement, but the construct is complex. There is large variation both in how satisfaction is measured and estimates of the proportion of people who are satisfied after surgery. The aim of this systematic review was to i) evaluate the proportion of people reported to be satisfied after total knee replacement for osteoarthritis; and ii) assess the content validity of the utilised satisfaction measures. Methods: We searched four literature databases with search phrases ‘Total Knee Arthroplasty’ OR ‘Total Knee Replacement’ AND ‘Patient satisfaction’ for studies that measured satisfaction at least 6 month post-unilateral primary total knee replacement for knee osteoarthritis. Identified studies were assessed for risk of bias, and studies at high risk of bias were excluded (PROSPERO: CRD42017058936). Meta-analysis was not appropriate due to the heterogeneity in satisfaction instruments, thus satisfaction scores were described. The content validity of satisfaction questionnaires was assessed using the COnsensus-based Standards for the selection of health status Measurement Instruments criteria. Results: The present review found heterogeneity in the satisfaction questions used, as well as the satisfaction estimates from the various studies. Only two satisfaction instruments were relevant for a Total Knee Replacement population and both failed assessment for content validity due to lack of patient involvement during development and testing in accordance with the COnsensus-based Standards for the selection of health status Measurement Instruments criteria. Conclusion: Future research should focus on qualitative methods to elicit patients' perspectives of satisfaction to build theoretical understanding.
Attitudes of patients and surgeons towards sham surgery trials: a protocol for a scoping review of attributes to inform a discrete choice experiment
(BMJ PUBLISHING GROUP, 2020-03-01)
INTRODUCTION: In order to properly evaluate the efficacy of orthopaedic procedures, rigorous, randomised controlled sham surgery trial designs are necessary. However, randomised controlled trials (RCTs) for surgery involving a placebo are ethically debated and difficult to conduct with many failing to reach their desired sample size and power. A review of the literature on barriers and enablers to recruitment, and patient and surgeon attitudes and preferences towards sham surgery trials, will help to determine the characteristics necessary for successful recruitment. METHODS AND ANALYSIS: This review will scope the diverse literature surrounding sham surgery trials with the aim of informing a discrete choice experiment to empirically test patient and surgeon preferences for different sham surgery trial designs. The scoping review will be conducted in accordance with the methodological framework described in Arksey and O'Malley (2005) and reported using the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols extension for Scoping Reviews. The review will be informed by a systematic search of Medline, Embase, PsycInfo, CINAHL and EconLit databases (from database inception to 21 June 2019), a Google Scholar search, and hand searching of reference lists of relevant studies or reviews. Studies or opinion pieces that involve patient, surgeon or trial characteristics, which influence the decision to participate in a trial, will be included. Study selection will be carried out independently by two authors with discrepancies resolved by consensus among three authors. Data will be charted using a standardised form, and results tabulated and narratively summarised with reference to the research questions of the review. ETHICS AND DISSEMINATION: The findings from this review will inform the design of a discrete choice experiment around willingness to participate in surgical trials, the outcomes of which can inform decision and cost-effectiveness models of sham surgery RCTs. The qualitative information from this review will also inform patient-centred outcomes research. The review will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: CRD42019133296.
The Surgeon's Role in the Opioid Crisis: A Narrative Review and Call to Action
(Frontiers Media SA, 2020)
Over the past two decades, there has been a sharp rise in the use of prescription opioids. In several countries, most notably the United States, opioid-related harm has been deemed a public health crisis. As surgeons are among the most prolific prescribers of opioids, growing attention is now being paid to the role that opioids play in surgical care. While opioids may sometimes be necessary to provide patients with adequate relief from acute pain after major surgery, the impact of opioids on the quality and safety of surgical care calls for greater scrutiny. This narrative review summarizes the available evidence on rates of persistent postsurgical opioid use and highlights the need to target known risk factors for persistent postoperative use before patients present for surgery. We draw attention to the mounting evidence that preoperative opioid exposure places patients at risk of persistent postoperative use, while also contributing to an increased risk of several other adverse clinical outcomes. By discussing the prevalence of excess opioid prescribing following surgery and highlighting significant variations in prescribing practices between countries, we note that there is a pressing need to optimize postoperative prescribing practices. Guided by the available evidence, we call for specific actions to be taken to address important research gaps and alleviate the harms associated with opioid use among surgical patients.
The Immediate Post-Operative Radiograph is an Unreliable Measure of Coronal Plane Alignment in Total Knee Replacement.
(Frontiers Media SA, 2014)
BACKGROUND: Restoration of a neutral mechanical axis is a primary goal of total knee replacement (TKR). A mechanical axis within 3° of neutral has been correlated with improved implant longevity, function, and patient satisfaction. We hypothesize that the immediate post-operative radiograph is an unreliable method of measuring alignment following TKR surgery. METHODS: Seventy-five consecutive patients had supine X-rays performed on day two post-operatively followed by standing long-leg radiographs (LLRs) 6 weeks post-operatively. Correlation was sought between the mechanical axis measured on the LLR and surrogate markers of alignment on the post-operative X-ray including component alignment and an estimation of anatomical alignment using the available length of femoral and tibial shafts. Inter- and intra-observer reliabilities were assessed. RESULTS: The mean mechanical axis on the LLR was 180.5 (SD 3.0, range 175.1-187.1). Mean offset between anatomical axis and mechanical axis was 6.4°. The mean anatomical axis measured on the short-leg X-ray was 174.9 (SD 2.4, range 169.5-181.3). Mechanical axis on the LLR was compared to the anatomical axis measured on the short-leg radiograph (SLR) + 6° with an interclass correlation coefficient of 0.588 (p < 0.001). The level of disagreement between the short- and long-leg X-rays was assessed using the Bland-Altman method and demonstrated clinically important discrepancies of 5 or more degrees in 9% of cases. Inter- and intra-observer agreements were high on all measures (p < 0.001). CONCLUSION: The long-leg weight bearing X-ray is an essential tool to accurately assess coronal plane alignment post TKR. While the immediate post-operative X-ray taken supine provides useful information to the surgeon on any immediate complications, our results indicate that it cannot be relied upon to determine correct restoration of the mechanical axis.
The effect of mindfulness training prior to total joint arthroplasty on post-operative pain and physical function: study protocol for a randomised controlled trial
(BioMed Central, 2014-06-05)
BACKGROUND: Osteoarthritis is a leading cause of disability in developed nations. In Australia it afflicts 16.5% of the adult population. Total joint arthroplasty is considered the treatment of choice for end stage osteoarthritis. The number of total joint arthroplasties undertaken in Australia has doubled over the last decade (more than 80,000 procedures in 2011). The incidence of pre-operative psychological distress in this group of patients is reported between 30% and 60% and pre-operative psychological distress is associated with poorer pain and functional outcomes after surgery. This study will use a mindfulness-based psychological intervention to enhance outcomes in people undergoing total joint arthroplasty and, in addition, will test hypotheses about coping with chronic illness in an aged population. This study is the first of its kind and will provide a greater understanding of the role of a mental health enhancement program on the physical recovery of total joint arthroplasty patients. METHODS/DESIGN: One hundred and fifty people with end-stage arthritis on the waiting list for total hip or knee arthroplasty will be recruited and randomly allocated to one of two groups using computer-generated block randomisation. A randomised controlled trial adhering to CONSORT guidelines will evaluate the efficacy of a mindfulness training program (weekly group-based classes in mindfulness practice, 2 ½ hours, for 8 weeks plus a 7-hour Saturday session in Week 6) prior to total joint arthroplasty, compared to a "standard care" group who will undergo routine total joint arthroplasty. Primary outcomes will be evaluated by a blinded examiner at baseline, 3 and 12 months post-surgery, using a validated self-reported pain and physical function scale. Secondary outcomes will include i) a range of validated measures of psychological wellbeing and ii) health economic analysis. All analyses will be conducted on an intention to treat basis using linear regression models. Health economic modelling will be applied to estimate the potential cost-effectiveness of mindfulness training and total joint arthroplasty.
Patient Endorsement of the Outcome Measures in Rheumatology (OMERACT) Total Joint Replacement (TJR) clinical trial draft core domain set
BACKGROUND: A patient- and surgeon-Delphi-derived Outcome Measures in Rheumatology (OMERACT) draft core domain set for total joint arthroplasty (TJR) trials was recently developed. Our objective was to obtain further patient stakeholder endorsement of draft core domain set for TJR clinical trials. METHODS: We surveyed two patient groups: (1) OMERACT patient partners; and (2) patients who had undergone hip or knee TJR. Patients received an introductory email with explanations about the core domain set and instructions to rate the core domains, i.e., important aspects, of OMERACT TJR clinical trial draft core domain set. Rating was on a nominal scale, where 1-3 indicated a domain of limited importance, 4-6 an important, but not critical domain, and 7-9 a critical domain. We used Mann-Whitney test (a non-parametric test) to compare the distribution of ratings between the two groups. RESULTS: Thirty one survey participants from the OMERACT patient partner group and 118 knee/hip TJR patients responded with response rates of 66 and 80%, respectively. Majority of the survey respondents were female, 87 vs. 53%, and were 55 years or older, 57 vs. 94%. Median (interquartile range [IQR]) scores for six core domains by OMERACT and knee/hip TJR patient groups were, respectively: pain, 8 [8, 9] and 9 [8, 9]; function, 9 [8, 9] and 9 [8, 9]; patient satisfaction, 8 [8, 9] and 8 [7, 9]; revision surgery, 7 [7, 8] and 7 [5, 9]; adverse events, 8 [7, 9] and 8 [6, 9]; and death, 9 [6, 9] and 9 [4, 9]. No statistically significant differences in rating were noted for any of the six core domains between the two groups (p ≥ 0.31). Among the additional domains, ratings for patient participation did not differ by group (p = 0.98), but ratings for cost were significantly different (p = 0.005). Patients provided qualitative feedback regarding core domains, and did not propose any modifications to the draft core domain set. CONCLUSIONS: Two separate patient stakeholder groups endorsed the OMERACT TJR draft core domain set for TJR trials.
Barriers and facilitators to orthopaedic surgeons’ uptake of decision aids for total knee arthroplasty: a qualitative study
(BMJ Publishing Group, 2017-11)
Objectives: The demand for total knee arthroplasty (TKA) is increasing. Differentiating who will derive a clinically meaningful improvement from TKA from others is a key challenge for orthopaedic surgeons. Decision aids can help surgeons select appropriate candidates for surgery, but their uptake has been low. The aim of this study was to explore the barriers and facilitators to decision aid uptake among orthopaedic surgeons. Design: A qualitative study involving face-to-face interviews. Questions were constructed on the Theoretical Domains Framework to systematically explore barriers and facilitators. Setting: One tertiary hospital in Australia. Participants: Twenty orthopaedic surgeons performing TKA. Outcome measures: Beliefs underlying similar interview responses were identified and grouped together as themes describing relevant barriers and facilitators to uptake of decision aids. Results: While prioritising their clinical acumen, surgeons believed a decision aid could enhance communication and patient informed consent. Barriers identified included the perception that one’s patient outcomes were already optimal; a perceived lack of non-operative alternatives for the management of end-stage osteoarthritis, concerns about mandatory cut-offs for patient-centred care and concerns about the medicolegal implications of using a decision aid. Conclusions: Multifaceted implementation interventions are required to ensure that orthopaedic surgeons are ready, willing and able to use a TKA decision aid. Audit/ feedback to address current decision-making biases such as overconfidence may enhance readiness to uptake. Policy changes and/or incentives may enhance willingness to uptake. Finally, the design/implementation of effective non-operative treatments may enhance ability to uptake by ensuring that surgeons have the resources they need to carry out decisions.
Multicentre randomised double-blind placebo controlled trial of combination vancomycin and cefazolin surgical antibiotic prophylaxis: the Australian surgical antibiotic prophylaxis (ASAP) trial
(BMJ PUBLISHING GROUP, 2019-11-01)
INTRODUCTION: Resistant Gram-positive organisms, such as methicillin-resistant staphylococci, account for a significant proportion of infections following joint replacement surgery. Current surgical antimicrobial prophylaxis guidelines recommend the use of first-generation or second-generation cephalosporin antibiotics, such as cefazolin. Cefazolin, however, does not prevent infections due to these resistant organisms; therefore, new prevention strategies need to be examined. One proposed strategy is to combine a glycopeptide antibiotic with cefazolin for prophylaxis. The clinical benefit and cost-effectiveness of this combination therapy compared with usual therapy, however, have not been established. METHODS AND ANALYSIS: This randomised, double-blind, parallel, superiority, placebo-controlled, phase 4 trial will compare the incidence of all surgical site infections (SSIs) including superficial, deep and organ/space (prosthetic joint) infections, safety and cost-effectiveness of surgical prophylaxis with cefazolin plus vancomycin to that with cefazolin plus placebo. The study will be performed in patients undergoing joint replacement surgery. In the microbiological sub-studies, we will examine the incidence of SSIs in participants with preoperative staphylococci colonisation (Sub-Study 1) and incidence of VRE acquisition (Sub-Study 2). The trial will recruit 4450 participants over a 4-year period across 13 orthopaedic centres in Australia. The primary outcome is the incidence of SSI at 90 days post index surgery. Secondary outcomes include the incidence of SSI according to joint and microorganism and other healthcare associated infections. Safety endpoints include the incidence of acute kidney injury, hypersensitivity reactions and all-cause mortality. The primary and secondary analysis will be a modified intention-to-treat analysis consisting of all randomised participants who undergo eligible surgery. We will also perform a per-protocol analysis. ETHICS AND DISSEMINATION: The study protocol was reviewed and approved by The Alfred Hospital Human Research Ethics Committee (HREC/18/Alfred/102) on 9 July 2018. Study findings will be disseminated in the printed media, and learnt forums. TRIAL REGISTRATION NUMBER: ACTRN12618000642280.