The environmental impact of hip and knee arthroplasty: An analysis of carbon emissions and disposal costs.

BACKGROUND AND PURPOSE: The rise in hip and knee arthroplasty for osteoarthritis requires addressing healthcare system pollution to support Ireland's climate change goals. This research aimed to quantify waste generated and determine environmental and economic impacts to promote sustainable strategies in joint arthroplasty and shed light on the suboptimal waste management practices. METHODS: The study was conducted at National Orthopaedic Hospital Cappagh (NOHC), measuring waste generated during hip and knee arthroplasty. Clinical, domestic, and recycled waste weights were recorded, including the segregation of Central Sterile Supply Department (CSSD) Blue Wrap waste in ten operations. Kilograms of carbon dioxide emissions (kgCO2e) and disposal costs were calculated. RESULTS: In a sample of 100 joint arthroplasty operations, the study found that revision knees produced 23.58 â€‹kgCO2e per case, revision hips 23.50 â€‹kgCO2e, primary knees 15.82 â€‹kgCO2e, and primary hips 14.64 â€‹kgCO2e. CSSD Blue Wrap contributed on average 13.5% of OT waste. Extrapolating these findings to the estimated number of joint arthroplasties performed in 2022 â€‹at NOHC (1556 hip and knee joint arthroplasties), the emissions were estimated to be 24,576 kgCO2e, with the cost of disposal up to €29,228. Strategies to mitigate this waste have been identified and proposed. CONCLUSION: The research aimed to address the environmental impact of orthopaedic joint arthroplasties, offering strategies to reduce waste generation, carbon emissions, and cost. Utilising our methodology to calculate greenhouse gas emissions will empower sustainability offices to conduct their own waste audits and implementing our strategies for waste management practices can help minimise environmental waste.

Reproducible Synthesis of Biocompatible Albumin Nanoparticles Designed for Intra-articular Administration of Celecoxib to Treat Osteoarthritis.

Osteoarthritis (OA) is the most common form of arthritis, with intra-articular (IA) delivery of therapeutics being the current best option to treat pain and inflammation. However, IA delivery is challenging due to the rapid clearance of therapeutics from the joint and the need for repeated injections. Thus, there is a need for long-acting delivery systems that increase the drug retention time in joints with the capacity to penetrate OA cartilage. As pharmaceutical utility also demands that this is achieved using biocompatible materials that provide colloidal stability, our aim was to develop a nanoparticle (NP) delivery system loaded with the COX-2 inhibitor celecoxib that can meet these criteria. We devised a reproducible and economical method to synthesize the colloidally stable albumin NPs loaded with celecoxib without the use of any of the following conditions: high temperatures at which albumin denaturation occurs, polymer coatings, oils, Class 1/2 solvents, and chemical protein cross-linkers. The spherical NP suspensions were biocompatible, monodisperse with average diameters of 72 nm (ideal for OA cartilage penetration), and they were stable over 6 months at 4 °C. Moreover, the NPs loaded celecoxib at higher levels than those required for the therapeutic response in arthritic joints. For these reasons, they are the first of their kind. Labeled NPs were internalized by primary human articular chondrocytes cultured from the knee joints of OA patients. The NPs reduced the concentration of inflammatory mediator prostaglandin E2 released by the primaries, an indication of retained bioactivity following NP synthesis. Similar results were observed in lipopolysaccharide-stimulated human THP-1 monocytes. The IA administration of these NPs is expected to avoid side-effects associated with oral administration of celecoxib and to maintain a high local concentration in the knee joint over a sustained period. They are now ready for evaluation by IA administration in animal models of OA.

The Diagnostic Utility of Serum Metal Ion Markers for High-Grade Aseptic Lymphocyte-Dominated Vasculitis-Associated Lesions (ALVALs) in Revision Hip and Knee Arthroplasty: An International Multicenter Study.

BACKGROUND: Aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) are typically described in the context of metal-on-metal (MoM) hip bearings. This study explores the diagnostic utility of preoperative serum cobalt and chromium ion levels in determining the histological grade of ALVAL in revision hip and knee arthroplasty. METHODS: This was a multicenter retrospective review of 26 hips and 13 knees assessing the correlation between preoperative ion levels (mg/L (ppb)) and the histological grade of ALVAL from intraoperative specimens. The diagnostic ability of preoperative serum cobalt and chromium levels to determine high-grade ALVAL was assessed using a receiver operating characteristic (ROC) curve. RESULTS: In the knee cohort, there was a higher serum cobalt level in high-grade ALVAL cases (10.2 mg/L (ppb) versus 3.1 mg/L (ppb)) (P = .0002). The Area Under the Curve (AUC) was 1.00 (95% confidence interval (CI) 1.00 to 1.00). There was a higher serum chromium level in high-grade ALVAL cases (12.25 mg/L (ppb) versus 7.77 mg/L (ppb)) (P = .0002). The AUC was 0.806 (95% CI 0.555 to 1.00). In the hip cohort, there was a higher serum cobalt level in high-grade ALVAL cases (333.5 mg/L (ppb) versus 119.9 mg/L (ppb)) (P = .0831). The AUC was 0.619 (95% CI 0.388 to 0.849). There was a higher serum chromium level in high-grade ALVAL cases (186.4 mg/L (ppb) versus 79.3 mg/L (ppb)) (P = .183). The AUC was 0.595 (95% CI 0.365 to 0.824). CONCLUSIONS: Histologically, high-grade ALVAL has significantly higher preoperative serum cobalt and chromium ion levels in revision TKA. Preoperative serum ion levels have excellent diagnostic utility in revision TKA. Cobalt levels in revision THA have a fair diagnostic ability and chromium levels had a poor diagnostic ability.

Developmental dysplasia of the hip is common in patients undergoing total hip arthroplasty under 50 years of age.

INTRODUCTION: Developmental dysplasia of the hip (DDH) refers to congenital and/or developmental hip instability that can result in hip joint subluxation or dislocation. When detected neonatally, conservative treatment with hip bracing can restore normal hip anatomy. Missed detection of DDH in the neonatal period or late development of DDH often requires surgical intervention to correct the abnormal anatomy. Furthermore, despite surgical intervention, residual sequelae may persist leading to early osteoarthritis of the hip joint requiring joint replacement surgery. AIM: This study investigates the prevalence of hip dysplasia in patients undergoing total hip arthroplasty (THA) under 50 years of age. METHODS: The hip arthroplasty database at a national referral centre was investigated from January 2014 to December 2020. In patients under 50 years of age, those with an adequate pre-operative anteroposterior pelvic radiograph without previous hip arthroplasty were included, while those with inadequate radiographs were excluded. The following measurements were made on the contralateral non-operated hip: (1) lateral centre-edge angle (LCEA), (2) Tönnis angle, (3) acetabular version, (4) acetabular depth, (5) femoral head lateralisation, (6) femoral head extrusion index, and (7) acetabular depth-to-width ratio. RESULTS: In total, 451 patients were included in this study. Twenty two percent of the patients had hip dysplasia, based on a LCEA of <25° and 42.6% of patients had hip dysplasia, based on a Tönnis angle of > 10°. The mean LCEA and Tönnis angle were 31.47 ± 9.64 and 9.82 ± 6.79°, respectively. CONCLUSION: Hip dysplasia is common in patients undergoing THA under the age of 50 years with over 40% having dysplasia according to the Tönnis angle. Classification of primary and secondary osteoarthritis in the joint registries will benefit our knowledge on the prevalence of DDH in the adult population.

Identification of protective and 'at risk' HLA genotypes for the development of pseudotumours around metal-on-metal hip resurfacings.

Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings. A matched case-control study was performed using the prospectively-collected database at the host institution. In all, 16 MoM hip resurfacing 'cases' were identified as having symptomatic periprosthetic pseudotumours on preoperative metal artefact reduction sequence (MARS) MRI, and were subsequently histologically confirmed as high-grade aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) at revision surgery. 'Controls' were matched by implant type in the absence of evidence of pseudotumour. Blood samples from all cases and controls were collected prospectively for high resolution genetic a nalysis targeting 11 separate HLA loci. Statistical significance was set at 0.10 a priori to determine the association between HLA genotype and pseudotumour formation, given the small sample size. Using a previously-reported ALVAL classification, the majority of pseudotumour-positive caseswere found to have intermediate-grade group 2 (n = 10; 63%) or group 3 (n = 4; 25%) histological findings. Two further patients (13%) had high-grade group 4 lesions. HLA-DQB1*05:03:01 (p = 0.0676) and HLA-DRB1*14:54:01 (p = 0.0676) alleles were significantly associated with a higher risk of pseudotumour formation, while HLA-DQA1*03:01:01 (p = 0.0240), HLA-DRB1*04:04:01 (p = 0.0453), HLA-C*01:02:01 (p = 0.0453), and HLA-B*27:05:02 (p = 0.0855) were noted to confer risk reduction. These findings confirm the association between specific HLA genotypes and the risk of pseudotumour development around MoM hip resurfacings. Specifically, the two 'at risk' alleles (DQB1*05:03:01 and DRB1*14:54:01) may hold clinical value in preoperative screening and prospective surgical decision-making.

Total Hip Arthroplasty in the Setting of Post-Traumatic Arthritis Following Acetabular Fracture: A Systematic Review.

Background: Acetabular fractures are frequently associated with post-traumatic arthritis (PTA), for which total hip arthroplasty (THA) has emerged as the established procedure. The purpose of this systematic review is to report the patient outcomes, complications, and implant survival of delayed THA for patients with PTA following acetabular fracture. Methods: A systematic review was performed in December 2021 as per Preferred Reporting Items for Systematic Review and Meta-Analysis Guidelines to identify all studies reporting outcomes of delayed THA performed for PTA with a history of acetabular fracture. From an initial screen of 893 studies, 29 studies which met defined inclusion criteria including minimum 12 months of follow-up and minimum 10 THA were included in the final review. Results: A total of 1220 THA were reported across 29 studies, with 1174 THA completing a minimum of 1-year follow-up at a mean of 86 months. All 29 studies reported upon complications, with a control included in 6 for comparison. Higher complication rates were observed both in patients who had prior open reduction internal fixation and conservative treatment, most notably infection which was observed following 3.6% THA. The total joint revision rate was 9.7%. An improvement was noted in all 25 studies which recorded patient-reported outcomes, with a mean rise in the Harris hip score from 45 to 86 across 18 studies. Conclusions: THA may reduce reported pain levels and improve functional outcomes in selected patients experiencing PTA following acetabular fractures. There is an increased risk of complications, necessitating careful consideration when planning the operation and open discussion with prospective patients and caregivers.

Obesity trends over 10 years in primary hip and knee arthroplasty-a study of 12,000 patients.

OBJECTIVES/AIMS: Obesity and its increasing prevalence are global public health concerns. Following joint replacement, there is evidence to support that obese patients are more likely to suffer complications. We examined 10-year trends in BMI of the primary total hip and total knee replacement cohorts in our institution to discern whether the BMI of these patients has changed over time. METHODS: We examined BMI data of patients who underwent primary hip and knee arthroplasty from our institutional database from January 1, 2010 to December 31, 2019 (n = 12,169). We analysed trends in BMI over this period with respect to (i) surgical procedure, (ii) gender, and (iii) age categories. RESULTS: The overall number of surgical procedures increased over the study period which meant more obese patients underwent surgery over time. Average BMI did not change significantly over time; however, there was a statistically significant increase in BMI in females aged < 45 in both arthroplasty groups. CONCLUSION: The average BMI of patients undergoing primary hip and knee arthroplasty in our high-volume tertiary orthopaedic centre has remained relatively unchanged over the past 10 years; however, our local service is caring for a greater number of overweight/obese patients due to the increase in overall volume. This will have significant implications on health care expenditure and infrastructure going forward which further emphasises the importance of ongoing national obesity prevention strategies. The increase in BMI seen in females aged < 45 may mark an impending era of obese younger patients with end-stage osteoarthritis.

Tourniquet use during primary total knee arthroplasty-a survey of Irish orthopaedic surgeons in 2022.

BACKGROUND: Tourniquet use during primary total knee arthroplasty is a debated topic in the literature with no consensus on its optimal use. AIM: To analyse current tourniquet practice amongst Irish orthopaedic surgeons performing primary total knee arthroplasty surgery. To evaluate if there has been a shift in practice in recent years and to explore potential reasons behind this. METHODS: An eleven-question online survey was developed using the online platform SurveyMonkey. This was distributed by email to Irish orthopaedic surgeons via the Irish Institute of Trauma and Orthopaedic Surgery. RESULTS: Fifty responses were included in the final analysis of this study. Eighteen (36%) respondents reported changing their tourniquet use in the past 5 years. Thirty-one (62%) respondents reported inflating the tourniquet for the entire case, with the remaining never applying a tourniquet (n = 6, 12%), applying a tourniquet but not routinely inflating it (n = 3, 6%), or inflating the tourniquet only during cementation (n = 5, 10%). The number of years of experience as a consultant appeared to impact tourniquet use in a bimodal pattern. CONCLUSION: While the majority of Irish orthopaedic surgeons in this survey inflate a tourniquet for the entire surgical procedure, there is a definite shift towards reduced tourniquet use compared to previous Irish, UK, and American surveys.

Third and fourth generation ceramic-on-ceramic total hip arthroplasty at a minimum of ten years.

Background: Ceramic on Ceramic bearings in Total Hip Arthroplasty (THA) afford a low friction coefficient, low wear rates and extreme hardness. Significant complications include hip squeak, ceramic fracture and poor polyethylene performance in revision procedures due to imbedding of abrasive microscopic ceramic fragments. We report on the results of this bearing at a minimum of 10 years. Methods: A single-centre retrospective review of 449 THAs was performed. Primary outcome measures included aseptic revision and all-cause revision rates at a minimum of 10 years post operatively. Evaluation of functionality was performed with WOMAC and SF-36 scores which were performed pre-operatively and at intervals of 6 months, one year, 2 years, 5 years and 10 years post operatively. Results: There was a 6.2% (n = 28) all-cause and 5.3% (n = 24) aseptic revision rate for ceramic on ceramic total hip arthroplasty at minimum of 10 years with a mean time to revision 4.8 years (range 2 months-11.6 years). Notably, there were 2 revisions for ceramic head fracture, one for ceramic liner fracture, 3 for aseptic loosening and 3 revisions for squeaking. Pain of unknown origin was the most common reason for revision. There was an improvement in postoperative WOMAC scores from a mean of 59.8 (range 15-95) pre-operatively to a mean of 15.6 (range 0-78) at 10 years. Conclusion: This study showed good functional outcomes but high revision rates for CoC THA at a minimum of 10 years. Our rates of ceramic fracture were consistent with other studies.

Evaluation of a co-culture of rapidly isolated chondrocytes and stem cells seeded on tri-layered collagen-based scaffolds in a caprine osteochondral defect model.

Cartilage has poor regenerative capacity and thus damage to the joint surfaces presents a major clinical challenge. Recent research has focussed on the development of tissue-engineered and cell-based approaches for the treatment of cartilage and osteochondral injuries, with current clinically available cell-based approaches including autologous chondrocyte implantation and matrix-assisted autologous chondrocyte implantation. However, these approaches have significant disadvantages due to the requirement for a two-stage surgical procedure and an in vitro chondrocyte expansion phase which increases logistical challenges, hospital times and costs. In this study, we hypothesized that seeding biomimetic tri-layered scaffolds, with proven regenerative potential, with chondrocyte/infrapatellar fat pad stromal cell co-cultures would improve their regenerative capacity compared to scaffolds implanted cell-free. Rapid cell isolation techniques, without the requirement for long term in vitro culture, were utilised to achieve co-cultures of chondrocytes and stromal cells and thus overcome the limitations of existing cell-based techniques. Cell-free and cell-seeded scaffolds were implanted in osteochondral defects, created within the femoral condyle and trochlear ridge, in a translational large animal goat model. While analysis showed trends towards delayed subchondral bone healing in the cell-seeded scaffold group, by the 12 month timepoint the cell-free and cell-seeded groups yield cartilage and bone tissue with comparable quality and quantity. The results of the study reinforce the potential of the biomimetic tri-layered scaffold to repair joint defects but failed to demonstrate a clear benefit from the addition of the CC/FPMSC co-culture to this scaffold. Taking into consideration the additional cost and complexity associated with the cell-seeded scaffold approach, this study demonstrates that the treatment of osteochondral defects using cell-free tri-layered scaffolds may represent a more prudent clinical approach.

Revision of total knee replacement (TKR) secondary to raised cobalt levels: should this be considered in the painful TKR patient?

A 63-year-old woman was referred to the specialised knee revision clinic with ongoing knee pain after total knee replacement. She incidentally had cobalt and chromium levels measured. These were seen to be elevated. Comprehensive assessment and investigation did not identify any other source of cobalt or chromium. Aseptic loosening of the knee was diagnosed, and the knee was revised. At the time of surgery, the tissue was seen to be darkened consistent with metallosis. Multiple samples excluded infection on extended cultures. Aspirated fluid showed that periprosthetic fluid had elevated cobalt levels. The knee was successfully revised with good symptomatic outcome and significantly, over the course of several months post-revision, the cobalt and chromium levels returned to normal.

Organelle calcium-derived voltage oscillations in pacemaker neurons drive the motor program for food-seeking behavior in Aplysia.

The expression of motivated behaviors depends on both external and internally arising neural stimuli, yet the intrinsic releasing mechanisms for such variably occurring behaviors remain elusive. In isolated nervous system preparations of Aplysia, we have found that irregularly expressed cycles of motor output underlying food-seeking behavior arise from regular membrane potential oscillations of varying magnitude in an identified pair of interneurons (B63) in the bilateral buccal ganglia. This rhythmic signal, which is specific to the B63 cells, is generated by organelle-derived intracellular calcium fluxes that activate voltage-independent plasma membrane channels. The resulting voltage oscillation spreads throughout a subset of gap junction-coupled buccal network neurons and by triggering plateau potential-mediated bursts in B63, can initiate motor output driving food-seeking action. Thus, an atypical neuronal pacemaker mechanism, based on rhythmic intracellular calcium store release and intercellular propagation, can act as an autonomous intrinsic releaser for the occurrence of a motivated behavior.

Regional trauma patterns during the COVID-19 pandemic.

BACKGROUND: The current pandemic has impacted heavily on health systems, making unprecedented demands on resources, and forcing reconfiguration of services. Trauma and orthopaedic units have cancelled elective surgery, moved to virtual based clinics and have been forced to reconsider the provision of trauma. Our national elective orthopaedic centre has been re-designated as a trauma centre to allow tertiary centres re-direct triaged trauma. Many governments, as part of their COVID-19 management, have significantly restricted activity of the general population. We proposed that trauma patterns would change alongside these changes and maintaining existing standards of treatment would require dedicated planning and structures. METHODS: Referrals over a six-week period (March 15th to April 30th) were retrospectively reviewed. Data was collected directly from our referral database and a database populated. Analysis was performed to assess trauma volume, aetiology, and changes in trends. RESULTS: There were one hundred and fifty-nine referrals from three individual hospitals within the timeframe. Mean age of patient's referred was 55 (range17-92). Males accounted for 45% of cases. F&A injuries were the most common (32%), followed by H&W (28%), UL (17%), H&F (16%) and K&T (7%). In comparison to the corresponding time-period in 2019, trauma theatre activity reduced by almost one half (45.3%) CONCLUSION: The majority of trauma referred to our Dublin based centre during COVID-19 related population restrictions appears to be home based and trauma volumes have decreased. Significant reductions are apparent in work and sport related injuries suggestive of compliance with COVID-19 activity guidelines. Maintaining existing standards of treatment requires dedicated planning.

Crisis change management during COVID-19 in the elective orthopaedic hospital: Easing the trauma burden of acute hospitals.

INTRODUCTION: With the emergence of the 2019 novel coronavirus and its resulting pandemic status in March 2020 all routine elective orthopaedic surgery was cancelled in our institution. The developing picture in Italy, of acute hospitals becoming overwhelmed with treating patients suffering with severe and life-threatening symptoms from the disease, prompted the orthopaedic surgeons to formulate a plan to transfer trauma patients requiring surgery to the elective hospital to unburden the acute hospital system. METHODS: Under the threat of this pandemic; protocols and algorithms were established for referral, acceptance and care of trauma patients from acute hospitals in the region. Each day, as new guidance on COVID-19 emerged, our process and algorithms were adjusted to reflect pertinent change. RESULTS: The screening of all patients referred, worked well in keeping our hospital "COVID-free" with respect to patients undergoing operations. An upward trend in cases referred reflected the decreased capacity in the acute hospitals due to rising cases of COVID-19 within the hospital network. During the first 7 weeks of the pandemic 308 operations were performed, (31.1% upper limb, 33.4% lower limb, 4.1% spine, 14.1% urgent elective, 17.4% plastic surgery cases). Regular review and audit of the activity in the hospital as well as communication with the referring teams enabled appropriate planning to accommodate the increase in case-mix as the need arose. DISCUSSION: This paper details the steps that were taken in planning for such a change in management specific to the orthopaedic surgery setting and the lessons learnt during this process. The success of the development of this pathway was facilitated by clear communication channels, flexibility to adapt to changing process and feedback from all stakeholders. The implementation of this pathway allowed the unburdening of acute hospitals dealing with the pandemic that was steadily reducing access to operating theatres and anaesthetic resources.

Outcomes of the Exeter V40 cemented femoral stem at a minimum of ten years in a non-designer centre.

AIMS: The Exeter V40 cemented femoral stem was first introduced in 2000. The largest single-centre analysis of this implant to date was published in 2018 by Westerman et al. Excellent results were reported at a minimum of ten years for the first 540 cases performed at the designer centre in the Exeter NHS Trust, with stem survivorship of 96.8%. The aim of this current study is to report long-term outcomes and survivorship for the Exeter V40 stem in a non-designer centre. METHODS: All patients undergoing primary total hip arthroplasty using the Exeter V40 femoral stem between 1 January 2005 and 31 January 2010 were eligible for inclusion. Data were collected prospectively, with routine follow-up at six to 12 months, two years, five years, and ten years. Functional outcomes were assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. Outcome measures included data on all components in situ beyond ten years, death occurring within ten years with components in situ, and all-cause revision surgery. RESULTS: A total of 829 stems in 745 patients were included in the dataset; 155 patients (20.8%) died within ten years, and of the remaining 664 stems, 648 stems (97.6%) remained in situ beyond ten years. For the 21 patients (2.5%) undergoing revision surgery, 16 femoral stems (1.9%) were revised and 18 acetabular components (2.2%) were revised. Indications for revision in order of decreasing frequency were infection (n = 6), pain (n = 6), aseptic component loosening (n = 3), periprosthetic fracture (n = 3), recurrent dislocation (n = 2), and noise production (ceramic-on-ceramic squeak) (n = 1). One patient was revised for aseptic stem loosening. The mean preoperative WOMAC score was 61 (SD 15.9) with a mean postoperative score of 20.4 (SD 19.3) (n = 732; 88.3%). CONCLUSION: The Exeter V40 cemented femoral stem demonstrates excellent functional outcomes and survival when used in a high volume non-designer centre. Outcomes are comparable to those of its serially validated predecessor, the Exeter Universal stem.Cite this article: Bone Jt Open 2020;1-12:743-748.

Quantifying the impact of the COVID-19 pandemic on orthopaedic trainees: a national perspective.

AIMS: We aim to objectively assess the impact of COVID-19 on mean total operative cases for all indicative procedures (as outlined by the Joint Committee on Surgical Training (JCST)) experienced by orthopaedic trainees in the deanery of the Republic of Ireland. Subjective experiences were reported for each trainee using questionnaires. METHODS: During the first four weeks of the nationwide lockdown due to COVID-19, the objective impact of the pandemic on each trainee's surgical caseload exposure was assessed using data from individual trainee logbook profiles in the deanery of the Republic of Ireland. Independent predictor variables included the trainee grade (ST 3 to 8), the individual trainee, the unit that the logbook was reported from, and the year in which the logbook was recorded. We used the analysis of variance (ANOVA) test to assess for any statistically significant predictor variables. The subjective experience of each trainee was captured using an electronic questionnaire. RESULTS: The mean number of total procedures per trainee over four weeks was 36.8 (7 to 99; standard deviation (SD) 19.67) in 2018, 40.6 (6 to 81; SD 17.90) in 2019, and 18.3 (3 to 65; SD 11.70) during the pandemic of 2020 (p = 0.043). Significant reductions were noted for all elective indicative procedures, including arthroplasty (p = 0.019), osteotomy (p = 0.045), nerve decompression (p = 0.024) and arthroscopy (p = 0.024). In contrast, none of the nine indicative procedures for trauma were reduced. There was a significant inter-unit difference in the mean number of total cases (p = 0.029) and indicative cases (p = 0.0005) per trainee. We noted that 7.69% (n = 3) of trainees contracted COVID-19. CONCLUSION: During the COVID-19 pandemic, the mean number of operative cases per trainee has been significantly reduced for four of the 13 indicative procedures, as outlined by the JCST. Reassignment of trainees to high-volume institutions in the future may be a plausible approach to mitigate significant training deficits in those trainees worst impacted by the reduction in operative exposure.

The development of natural polymer scaffold-based therapeutics for osteochondral repair.

Due to the limited regenerative capacity of cartilage, untreated joint defects can advance to more extensive degenerative conditions such as osteoarthritis. While some biomaterial-based tissue-engineered scaffolds have shown promise in treating such defects, no scaffold has been widely accepted by clinicians to date. Multi-layered natural polymer scaffolds that mimic native osteochondral tissue and facilitate the regeneration of both articular cartilage (AC) and subchondral bone (SCB) in spatially distinct regions have recently entered clinical use, while the transient localized delivery of growth factors and even therapeutic genes has also been proposed to better regulate and promote new tissue formation. Furthermore, new manufacturing methods such as 3D bioprinting have made it possible to precisely tailor scaffold micro-architectures and/or to control the spatial deposition of cells in requisite layers of an implant. In this way, natural and synthetic polymers can be combined to yield bioactive, yet mechanically robust, cell-laden scaffolds suitable for the osteochondral environment. This mini-review discusses recent advances in scaffolds for osteochondral repair, with particular focus on the role of natural polymers in providing regenerative templates for treatment of both AC and SCB in articular joint defects.

Aspirin compared to enoxaparin or rivaroxaban for thromboprophylaxis following hip and knee replacement.

Background The risk of venous thromboembolism following major orthopaedic surgery is among the highest for all surgical specialties. Our hospital guidelines for thromboprophylaxis following elective primary total hip or knee replacement are based on American College of Chest Physicians guidance. The most recent change to local guidelines was the introduction of the extended aspirin regimen as standard thromboprophylaxis. Objective To establish the appropriateness of this regimen by comparing venous thromboembolism rates in patients receiving extended aspirin to previous regimens. Setting The largest dedicated orthopaedic hospital in Ireland. Methods This was a retrospective cohort study. Data were collected from patient record software. All eligible patients undergoing primary total hip or knee replacement between 1st January 2010 and 30th June 2016 were included. Main outcome measure Venous thromboembolism up to 6 months post-operatively. Results Of the 6548 participants (55.3% female, mean age 65.4 years (± 11.8 years, 55.8% underwent total hip replacement), venous thromboembolism occurred in 65 (0.99%). Venous thromboembolism rate in both the inpatient enoxaparin group (n = 961) and extended aspirin group (n = 3460) was 1.04% and was 0.66% in the modified rivaroxaban group (n = 1212). Non-inferiority analysis showed the extended aspirin regimen to be equivalent to the modified rivaroxaban regimen. History of venous thromboembolism was the only significant demographic risk factor for post-operative venous thromboembolism (0.87% vs. 3.54%, p  = 0.0002). Conclusion In daily clinical practice, extended aspirin regimen is at least as effective as modified rivaroxaban for preventing clinically important venous thromboembolism among patients undergoing hip or knee arthroplasty who are discharged from the hospital without complications. Aspirin can be considered a safe and effective agent in the prevention of venous thromboembolism after total hip or total knee replacement.

Geographical variation in musculoskeletal surgical care in public hospitals in Ireland: a repeated cross-sectional study.

OBJECTIVE: To examine the extent of geographical variation across musculoskeletal surgical procedures and associated factors in Ireland. DESIGN: Repeated cross-sectional study. SETTING: 36 public hospitals in Ireland. PARTICIPANTS: Adult admissions for hip fracture, hip and knee replacement, knee arthroscopy and lumbar spine interventions over 5 years (2012-2016). PRIMARY OUTCOME MEASURE: Standardised discharge rate (SDR). ANALYSIS: Age and sex SDRs were calculated for 21 geographical areas. Extremal quotients, coefficients of variation and systematic components of variance were calculated. Linear regression analyses were conducted exploring the relationship between SDRs and year, unemployment, % urban population, number of referral hospitals, % on waiting lists>6 months and % with private health insurance for each procedure. RESULTS: Across 36 public hospitals, n=102 756 admissions were included. Hip fracture repair showed very low variation. Elective hip and knee procedures showed high variation in particular years, while variation for lumbar interventions was very high. Knee arthroscopy rates decreased over time. Higher unemployment was associated with knee and hip replacement rates and urban areas had lower hip replacement rates. Spinal procedure rates were associated with a lower number of referral hospitals in a region and spinal injection rates were associated with shorter waiting lists. A higher proportion of patients having private health insurance was associated with higher rates of hip and knee replacement and lumbar spinal procedures. CONCLUSIONS: Variation and factors associated with SDRs for publicly funded hip and knee procedures are consistent with similar international research in this field. Further research should explore reasons for high rates of spinal injections and the impact of private practice on musculoskeletal procedure variation.