Evidence-based review of safe theatre practice during the COVID-19 pandemic beyond personal protective equipment.

INTRODUCTION: COVID-19 remains a threat for a fear of a second pandemic. Emergency orthopaedic operations are still among the most commonly performed procedures with increased risk of transmission of SARS CoV-2 to the patients and the healthcare workers. The aim of this study was to present the evidence available into best practices limiting the spread of COVID-19 in healthcare setting during current and future pandemics. METHODS: A review of the literature was performed in multiple databases (PubMed, the Cochrane Library, Google Scholar, World Health Organization and Centers for Disease Control), using 'COVID-19' with other relevant keywords in different combinations. Owing to the limited and heterogenous evidence available, data were presented in a narrative manner. FINDINGS: From the evidence gathered it was noted that a multimodal approach to minimising pathogen transmission is required. This primarily comprises the wider engineering and administrative controls to reduce the concentration of the pathogen and to separate staff and patients from it. Theatre isolation and traffic control bundling, theatre flow and logistics, ventilation and waste management form a pivotal role in the environmental/engineering controls. Administrative measures include policies for both patients and staff. For patients, isolation and preoperative screening are of utmost value. For staff, testing for COVID-19, risk assessment, redeployment and provision of persona; protective equipment, together with the necessary training are important administrative controls. CONCLUSION: We believe these measures are likely to improve the sustainability of resources and can be carried to elective settings in order to return to some form of normality and help to mitigate the effects of future pandemics.

Correction to: Uncemented Thompson's hemiarthroplasty: safe, palliative and cost-effective surgery in the infirm patient-a consecutive series of 1445 cases.

The original version of this article unfortunately contained a mistake. David Morley was not listed among the authors.

A microbiological assessment of sterile surgical helmet systems using particle counts and culture plates: recommendations for safe use whilst scrubbing.

BACKGROUND: Infection occurs in 2-4% of arthroplasty cases, and identifying potential sources of infection can help to reduce infection rates. The aim of this study was to identify the impact and potential for the contamination of hands and gowns whilst scrubbing using sterile surgical helmet systems (SSHSs). METHODS: A colony-forming unit (cfu) is a pathogenic particle of 0.5-5 µm. Standard arthroplasty hoods and SSHSs, with and without the fan switched on, were tested for a 3-min exposure (to represent scrubbing time) on three subjects and a mannequin with concurrent particle counts and culture plates. RESULTS: All SSHSs were positive for Gram-positive cocci, with a mean colony count of 410 cfu/m2. Background counts were lower for laminar flow areas [mean 0.7 particles/m3; 95% confidence interval (CI) 0-1.4] than scrub areas (mean 131.5 particles/m3; 95% CI 123.5-137.9; P=0.0003). However, neither grew any bacteria with a 2-min exposure. The background count increased 3.7 times with the fan switched on (total P=0.004, cfu P=0.047), and all helmets had positive cultures (mean 36 cfu/m2). There were no positive cultures with the standard arthroplasty hood or the SSHS with the fan switched off. In laminar flow areas, all cultures were negative and particle counts were low. CONCLUSIONS: Sterile gloves and gowns can be contaminated when scrubbing with the SSHS fan switched on. It is recommended that the fan should remain switched off when scrubbing until the hood and gown are in place, ideally in a laminar flow environment.

Uncemented Thompson's hemiarthroplasty: safe, palliative and cost-effective surgery in the infirm patient-a consecutive series of 1445 cases.

BACKGROUND: Guidelines on the management of displaced intracapsular fractures recommend using an Orthopaedic Data Evaluation Panel-rated cemented implant. Prior to the National Institute for Health and Care Excellence guidelines, uncemented implants were commonly used in the UK. METHODS: We retrospectively examined the outcomes of patients with uncemented Thompson's hemiarthroplasties at our unit, between April 2005 and December 2010. Patients who underwent revision surgery before December 2011 were identified. Implant survival calculation utilised the primary outcome of revision to total hip arthroplasty, revision hemiarthroplasty or excision arthroplasty. Patients who died post-operatively were identified and censored. RESULTS: A total of 1445 patients received uncemented Thompson's implant. Patient mean age was 82 years with 76% female. Forty-six (3.2%) patients required revision with 15% performed within 30 days of surgery and 62% within 1 year. Reasons for revision were infection (0.83%), acetabular erosion (0.83%) and loosening (0.62%). Twenty-seven patients (59% of total revisions) underwent revision to THA, 14 (30%) to excision arthroplasty and 5 (11%) to revision hemiarthroplasty. Cumulative survival rate was 98% at 1 year and 95% at 5 years. Thirty-day mortality was 7.1%. One-year mortality was 28.1%. CONCLUSION: Current guidelines strongly favour cemented hemiarthroplasty. Recognition that fractured hip patients are a non-homogeneous group is important. In patients with limited life expectancy, an uncemented Thompson is a quick, simple, palliative solution to early mobilisation. Correct surgical technique avoids using cement in this cohort, which is most vulnerable to bone cement implantation syndrome. Cost-effective resource utilisation with an increasingly elderly population remains a surgical responsibility.

Medium- and long-term results of high tibial osteotomy using Garches external fixator and gait analysis for dynamic correction in varus osteoarthritis of the knee.

In arthritis of the varus knee, a high tibial osteotomy (HTO) redistributes load from the diseased medial compartment to the unaffected lateral compartment. We report the outcome of 36 patients (33 men and three women) with 42 varus, arthritic knees who underwent HTO and dynamic correction using a Garches external fixator until they felt that normal alignment had been restored. The mean age of the patients was 54.11 years (34 to 68). Normal alignment was achieved at a mean 5.5 weeks (3 to 10) post-operatively. Radiographs, gait analysis and visual analogue scores for pain were measured pre- and post-operatively, at one year and at medium-term follow-up (mean six years; 2 to 10). Failure was defined as conversion to knee arthroplasty. Pre-operative gait analysis divided the 42 knees into two equal groups with high (17 patients) or low (19 patients) adductor moments. After correction, a statistically significant (p < 0.001, t-test,) change in adductor moment was achieved and maintained in both groups, with a rate of failure of three knees (7.1%), and 89% (95% confidence interval (CI) 84.9 to 94.7) survivorship at medium-term follow-up. At final follow-up, after a mean of 15.9 years (12 to 20), there was a survivorship of 59% (95% CI 59.6 to 68.9) irrespective of adductor moment group, with a mean time to conversion to knee arthroplasty of 9.5 years (3 to 18; 95% confidence interval ± 2.5). HTO remains a useful option in the medium-term for the treatment of medial compartment osteoarthritis of the knee but does not last in the long-term. Cite this article: Bone Joint J 2016;98-B:601-7.

Cause of death and factors associated with early in-hospital mortality after hip fracture.

The aims of this study were to identify the early in-hospital mortality rate after hip fracture, identify factors associated with this mortality, and identify the cause of death in these patients. A retrospective cohort study was performed on 4426 patients admitted to our institution between the 1 January 2006 and 31 December 2013 with a hip fracture (1128 male (26%), mean age 82.0 years (60 to 105)). Admissions increased annually, but despite this 30-day mortality decreased from 12.1% to 6.5%; 77% of these were in-hospital deaths. Male gender (odds ratio (OR) 2.0, 95% confidence interval (CI) 1.3 to 3.0), increasing age (age ≥ 91; OR 4.1, 95% CI 1.4 to 12.2) and comorbidity (American Society of Anesthesiologists grades 3 to 5; OR 4.2, 95% CI 2.0 to 8.7) were independently and significantly associated with increased odds of in-hospital mortality. From 220 post-mortem reports, the most common causes of death were respiratory infections (35%), ischaemic heart disease (21%), and cardiac failure (13%). A sub-group of hip fracture patients at highest risk of early death can be identified with these risk factors, and the knowledge of the causes of death can be used to inform service improvements and the development of a more didactic care pathway, so that multidisciplinary intervention can be focused for this sub-group in order to improve their outcome.

Properties of presynaptic P2X7-like receptors at the neuromuscular junction.

Adenosine triphosphate is released into the synaptic cleft of the neuromuscular junction during normal synaptic transmission, and in much greater quantities following injury and ischaemia. There is much data to suggest roles for presynaptic P2 receptors but little to demonstrate which specific receptor subunits are present. Here we show P2X7 receptor subunits on presynaptic motor nerve terminals from birth, but no evidence for P2X1, P2X2, P2X3, P2X4, P2X5 or P2X6 receptor subunits. Further, P2X receptor subunits are present as multimeric, membrane-inserted receptors. A selective agonist, 2'-3'-O-(4-benzoylbenzoyl)-adenosine 5'-triphosphate (BzATP: 100 microM), triggers vesicle release from motor nerve terminals, which is blocked by P2X7RS-specific concentrations of periodate oxidised ATP (OxATP: 100 microM) and brilliant blue G (BBG: 1 microM), but not by suramin (100 microM). Vesicle release is enhanced in the absence of extracellular divalent cations and occurs through activation of the ion channel and not any associated large pore, as we failed to label nerve terminals with large membrane-impermeant molecules after addition of BzATP. We conclude that a P2X7-like receptor is present at mouse motor nerve terminals, and that their activation promotes vesicle release.

Differential co-localisation of the P2X7 receptor subunit with vesicular glutamate transporters VGLUT1 and VGLUT2 in rat CNS.

Presynaptic P2X(7) receptors are thought to play a role in the modulation of transmitter release and have been localised to terminals with the location and morphology typical of excitatory boutons. To test the hypothesis that this receptor is preferentially associated with excitatory terminals we combined immunohistochemistry for the P2X(7) receptor subunit (P2X(7)R) with that for two vesicular glutamate transporters (VGLUT1 and VGLUT2) in the rat CNS. This confirmed that P2X(7)R immunoreactivity (IR) is present in glutamatergic terminals; however, whether it was co-localised with VGLUT1-IR or VGLUT2-IR depended on the CNS region examined. In the spinal cord, P2X(7)R-IR co-localised with VGLUT2-IR. In the brainstem, co-localisation of P2X(7)R-IR with VGLUT2-IR was widespread, but co-localisation with VGLUT1-IR was seen only in the external cuneate nucleus and spinocerebellar tract region of the ventral medulla. In the cerebellum, P2X(7)R-IR co-localised with both VGLUT1 and VGLUT2-IR in the granular layer. In the hippocampus it was co-localised only with VGLUT1-IR, including in the polymorphic layer of the dentate gyrus and the substantia radiatum of the CA3 region. In other forebrain areas, P2X(7)R-IR co-localised with VGLUT1-IR throughout the amygdala, caudate putamen, striatum, reticular thalamic nucleus and cortex and with VGLUT2-IR in the dorsal lateral geniculate nucleus, amygdala and hypothalamus. Dual labelling studies performed using markers for cholinergic, monoaminergic, GABAergic and glycinergic terminals indicated that in certain brainstem and spinal cord nuclei the P2X(7)R is also expressed by subpopulations of cholinergic and GABAergic/glycinergic terminals. These data support our previous hypothesis that the P2X(7)R may play a role in modulating glutamate release in functionally different systems throughout the CNS but further suggest a role in modulating release of inhibitory transmitters in some regions.