Aims

Global literature suggests that female surgical trainees have lower rates of independent operating (operative autonomy) than their male counterparts. The objective of this study was to identify any association between gender and lead/independent operating in speciality orthopaedic trainees within the UK national training programme.

Aims

Physician burnout and its consequences have been recognized as increasingly prevalent and important issues for both organizations and individuals involved in healthcare delivery. The purpose of this study was to describe and compare the patterns of self-reported wellness in orthopaedic surgeons and trainees from multiple nations with varying health systems.

Aim. To date, the value of culture results after a debridement, antibiotics and implant retention (DAIR) for early (suspected) prosthetic joint infection (PJI) as risk indicators in terms of prosthesis retention is not clear. At one year follow-up, the relative risk of prosthesis removal was determined for culture-positive and culture-negative DAIRs after primary total hip or knee arthroplasty. The secondary aim was to explore differences in patient characteristics, infection characteristics and outcomes between these two groups. Methods. A retrospective regional registry study was performed in a group of 359 patients (positive cultures: n = 299, negative cultures n = 60) undergoing DAIR for high suspicion of early PJI in the period from 2014 to 2019. Differences in patient characteristics, deceased patients and number of subsequent DAIRs between the positive and negative DAIR groups were analyzed using independent t-tests, Mann-Whitney, Pearson's Chi-square tests and Fisher's Exact tests. Results. Overall implant survival rate following DAIR was 89%. The relative risk for prosthesis removal was 7.4 times higher (95% confidence interval (CI) 1.0–53.1) in the positive DAIR group (37/299, 12.4%) compared to the negative DAIR group (1/60, 1.7%). The positive group had a higher body mass index (p = 0.034), rate of wound leakage of >10 days (p = 0.016) and more subsequent DAIRs (p = 0.006). Conclusion. Since implant survival results after DAIR are favorable, the threshold to perform a DAIR procedure in early PJI should be low in order to retain the prosthesis. A DAIR procedure in case of negative cultures does not seem to have unfavorable results in terms of prosthesis retention

Māori consistently have poorer health outcomes compared to non-Māori within Aotearoa. Numerous worldwide studies demonstrate that ethnic minorities receive less analgesia for acute pain management. We aimed to compare analgesic management of a common orthopaedic injury, tibial shaft fracture, between Māori and non-Māori. A retrospective cohort study from January 1. st. , 2015, to December 31. st. 2020 inclusive. Eligible patients were 16–65 years old and had isolated closed tibial shaft fractures. 104 patients were included in the study, 48 Māori and 56 Non-Māori. Baseline demographics were similar between the 2 cohorts. The primary outcome measure was type of analgesia charted on the ward. Secondary outcome measures were pre-hospital medications given, pain scores on arrival to the emergency department (ED) and the ward, time to analgesia in ED and type of analgesia given in ED. Statistics were calculated using Fisher's exact test, Pearson's chi-squared test or Wilcoxson's rank sum test as appropriate. No statistically significant differences were found in opiates or synthetics charted to Māori vs Non-Māori (83% vs 89% and 77% vs 88% respectively), opiates given in ED, time to analgesia in ED or ED and ward arrival pain scores. Of statistical significance is that Māori were less likely to receive pre-hospital medication compared to Non-Māori (54% vs 80% respectively, p=0.004). Māori were significantly less likely to receive pre-hospital pain medication compared to Non-Māori. However no other statistically significant findings were found when comparing pain scores, time to analgesia or type of pain relief charted for Māori vs non-Māori. The reasons for Māori receiving significantly less prehospital medication were not explored in this study and further investigation is required to reduce the bias that exists in this area

Simultaneous bilateral total hip arthroplasty (THA) in patients with bilateral hip osteoarthritis is gradually becoming attractive, as it requires a single anesthesia and hospitalization. However, there are concerns about the potential complications following this surgical option. The purpose of this study is to compare the short-term major and minor complications and assess the readmission rate, between patients treated with same-day bilateral THA and those with staged procedures within a year. We retrospectively reviewed the charts of all patients with bilateral hip osteoarthritis that underwent simultaneous or staged (within a year) bilateral total THA in our institution, between 2016-2020. Preoperative patient variables between the two groups were compared using the 2-sample t-test for continuous variables, the Fisher's exact test for binary variables, or the chi-square test for multiple categorical variables. Similarly, differences in the 30-day major and minor complications and readmission rates were assessed. A logistic regression model was also developed to identify potential risk factors. A total of 160 patients (mean age: 64.3 years, SD: ±11.7) that underwent bilateral THA was identified. Seventy-nine patients were treated with simultaneous and eighty-one patients with staged procedures. There were no differences in terms of preoperative laboratory values, gender, age, Body Mass Index (BMI), or American Society of Anesthesiologists Scores (ASA) (p>0.05) between the two groups. Patients in the simultaneous group were more likely to receive general anesthesia (43% vs 9.9%, p0.05). After controlling for potential confounders, the multivariable logistic regression analysis showed similar odds of having a major (odds ratio 0.29, 95% confidence interval [0.30-2.88], p=0.29) or minor (odds ratio 1.714, 95% confidence interval [0.66-4.46], p=0.27) complication after simultaneous compared to staged bilateral THA. No differences in emergency department visits or readmission for reasons related to the procedure were recorded (p>0.05). This study shows that similar complication and readmission rates are expected after simultaneous and staged THAs. Simultaneous bilateral THA is a safe and effective procedure, that should be sought actively and counselled by surgeons, for patients that present with radiologic and clinical bilateral hip disease

Hip resurfacing may be a useful surgical procedure when patient selection is correct and only implants with superior performance are used. In order to establish a body of evidence in relation to hip resurfacing, pseudotumour formation and its genetic predisposition, we performed a case-control study investigating the role of HLA genotype in the development of pseudotumour around MoM hip resurfacings. All metal-on-metal (MoM) hip resurfacings performed in the history of the institution were assessed. A total of 392 hip resurfacings were performed by 12 surgeons between February 1st 2005 and October 31st 2007. In all cases, pseudotumour was confirmed in the preoperative setting on Metal Artefact Reduction Sequencing (MARS) MRI. Controls were matched by implant (ASR or BHR) and absence of pseudotumour was confirmed on MRI. Blood samples from all cases and controls underwent genetic analysis using Next Generation Sequencing (NGS) assessing for the following alleles of 11 HLA loci (A, B, C, DRB1, DRB3/4/5, DQA1, DQB1, DPB1, DPA1). Statistical significance was determined using a Fisher's exact test or Chi-Squared test given the small sample size to quantify the clinical association between HLA genotype and the need for revision surgery due to pseudotumour. Both groups were matched for implant type (55% ASR, 45% BHR in both the case and control groups). According to the ALVAL histological classification described by Kurmis et al., the majority of cases (63%, n=10) were found to have group 2 histological findings. Four cases (25%) had group 3 histological findings and 2 (12%) patients had group 4 findings. Of the 11 HLA loci analysed, 2 were significantly associated with a higher risk of pseudotumour formation (DQB1*05:03:01 and DRB1*14:54:01) and 4 were noted to be protective against pseudotumour formation (DQA1*03:01:01, DRB1*04:04:01, C*01:02:01, B*27:05:02). These findings further develop the knowledge base around specific HLA genotypes and their role in the development of pseudotumour formation in MoM hip resurfacing. Specifically, the two alleles at higher risk of pseudotumour formation (DQB1*05:03:01 and DRB1*14:54:01) in MoM hip resurfacing should be noted, particularly as patient-specific genotype-dependent surgical treatments continue to develop in the future

Guided growth is commonly performed by placing an extra-periosteal two-hole plate across the growth plate with one epiphyseal and one metaphyseal screw. Recent work by Keshet et al. (2019) investigated the efficacy of the removal of the metaphyseal screw only (“sleeper plate”) after correction. They concluded the practice to be unnecessary as only 19% of patient show recurrence of deformity. The aim of this study is to examine the incidence of rebound and undesired bony in-growth of the plate (“tethering”) after metaphyseal screw removal only. In this retrospective case series, patient data on 144 plates inserted around the knee was obtained. Plates still in situ (n=69) at time of study and full hardware removal (n=50) were excluded. The remaining 25 plates had a metaphyseal screw only removed after deformity correction. We analyzed the rate of re-bound, tethering and maintenance of correction in two age groups at latest follow-up for a mean of 3.5 years (1.25 to five). Fisher's exact test with Freeman-Halton extension was used to analyze the two by three contingency table. Twenty-five plates were identified as “sleeper plates” in our series. 13 plates (52%) maintained the achieved correction after a mean of 21 months (four to 39), nine plates (36%) required screw re-insertion due to rebound after a mean of 22 months (12-48) from screw removal, and four plates (16%) showed tethering with undesired continuation of guided growth after a mean of 14 months (seven to 22) from screw removal. Younger patients (years at time of plate insertion) had higher rates of rebound and tethering (p=.0112, Fisher's exact test). All Tethering occurred in titanium plates, none occurred in steel plates. The sleeper plate is an acceptable treatment strategy for coronal deformities around the knee. Rebounding and tethering are potential outcomes that occur in younger patients and should be disclosed to patients; titanium plates may increase the risk of tethering, however further long-term follow-up is needed. We stress the importance of close post-operative follow up to identify tethering early and prevent over correction. The sleeper plate technique is a viable option in younger children with congenital abnormalities, however, continued monitoring of alignment is necessary after screw removal to check for rebound and tethering

Aim. In severe cases of postoperative spinal implant infections (PSII) multiple revision surgeries may be needed. Little is known if changes of the microbiological spectrum and antibiotic resistance pattern occur between revision surgeries. Therefore, the aim of this study was to analyze the microbiological spectrum and antibiotic resistance pattern in patients with multiple revision surgeries for the treatment of PSII. Furthermore, changes of the microbiological spectrum, distribution of mono vs. polymicrobial infections, and changes of the antimicrobial resistance profile in persistent microorganisms were evaluated. Method. A retrospective analysis of a prospectively maintained single center spine infection database was performed with a minimum follow-up of 3 years. Between 01/2011 and 12/2018, 103 patients underwent 248 revision surgeries for the treatment of PSII. Overall, 20 patients (6 male/14 female) underwent 82 revisions for PSII (median 3; range 2–12). There were 55/82 (67.1%) procedures with a positive microbiological result. Microbiological analysis was performed on tissue and implant sonication fluid. Changes in microbial spectrum and antibiotic resistance pattern between surgeries were evaluated using Chi-Square and Fisher's exact test. Results. In total, 74 microorganisms (83.3% gram-positive; 10.8% gram-negative) were identified. The most common microorganisms were Staphylococcus epidermidis (18.9%) and Cutibacterium acnes (18.9%). All S. epidermidis identified were methicillin-resistant (MRSE). Overall, there were 15/55 (27.3%) polymicrobial infections. The microbiological spectrum changed in 57.1% (20/35) between the revision stages over the entire PSII period. In 42.9% (15/35) the microorganism persisted between the revision surgeries stages. Overall, changes of the antibiotic resistance pattern were seen in 17.4% (8/46) of the detected microorganisms comparing index revision and all subsequent re-revisions. Moreover, higher resistance rates were found for moxifloxacin and for ciprofloxacin at first re-revision surgery compared with index PSII revision. Resistances against vancomycin increased from 4.5% (1/23) at index PSII revision to 7.7% (2/26) at first re-revision surgery. Conclusions. Changes of the microbiological spectrum and the resistance pattern can occur in patients with severe PSII who require multiple revision surgeries. It is important to consider these findings in the antimicrobial treatment of PSII. The microbiological analysis of intraoperative tissue samples should be performed at every revision procedure for PSI

In response to the COVID-19 pandemic public health measures were implemented to limit virus spread. After initial implementation of a province-wide lockdown (Stage 1), there followed a sequential ease of restrictions through Stages 2 and 3 over a 6-month period from March to September 2020 (Table 1). We aimed to determine the impact of COVID-19 public health measures on the epidemiology of operative paediatric orthopaedic trauma and to determine differential effects of each stage of lockdown. A retrospective cohort study was performed comparing all emergency department (ED) visits for musculoskeletal trauma and operatively treated orthopaedic trauma cases at a Level-1 paediatric trauma center during Mar-Sep 2020 (pandemic), compared with Mar-Sep 2019 (pre-pandemic). All operative cases were analyzed based on injury severity, mechanism of injury (MOI) and anatomic location (AL). Comparisons between groups were assessed using chi-square testing for categorical variables, and student t-tests and Fisher's exact tests for continuous variables. During the pandemic period, ED visits for orthopaedic trauma decreased compared to pre-pandemic levels by 23% (1370 vs 1790 patients) and operative treatment decreased by 28% (283 vs 391 patients). There was a significant decrease in the number of operative cases per day in lockdown Stage 1 (1.25 pandemic vs 1.90 pre- pandemic; p < 0 .001) and Stage 2 (1.65 pandemic vs 3.03 pre-pandemic; p< 0.001) but no difference in operative case number during Stage 3 (2.18 pandemic vs 2.45 pre-pandemic; p=0.35). Significant differences were found in MOI and AL during Stage 1 (p < 0 .001) and Stage 2 (p < 0 .001) compared to pre-pandemic. During Stage 1 and 2, playground injuries decreased by 95% and 82%, respectively; sports injuries decreased by 79% and 13%, and trampoline injuries decreased 44% and 43%, compared to pre-pandemic. However, self-propelled transit injuries (bicycles/skateboards) increased during Stage 1 and Stage 2 by 67% and 28%, respectively compared to pre- pandemic. During lockdown Stage 3 there were no differences in MOI nor AL. There were no significant differences in injury severity in any lockdown stage compared to pre-pandemic. COVID-19 lockdown measures significantly reduced the burden of operative paediatric orthopaedic trauma. Differences in volume, mechanism and pattern of injuries varied by lockdown stage offering evidence of the burden of operative trauma related to specific childhood activities. These findings will assist health systems planning for future pandemics and suggest that improvements in safety of playgrounds and self-propelled transit are important in reducing severe childhood injury requiring operative intervention. For any figures or tables, please contact the authors directly

There has been a substantial increase in the surgical treatment of unstable chest wall injuries recently. While a variety of fixation methods exist, most surgeons have used plate and screw fixation. Rib-specific locking plate systems are available, however evidence supporting their use over less-expensive, conventional plate systems (such as pelvic reconstruction plates) is lacking. We sought to address this by comparing outcomes between locking plates and non-locking plates in a cohort of patients from a prior randomized trial who received surgical stabilization of their unstable chest wall injury. We used data from the surgical group of a previous multi-centred, prospective, randomized controlled trial comparing surgical fixation of acute, unstable chest wall injuries to non-operative management. In this substudy, our primary outcome was hardware-related complications and re-operation. Secondary outcomes included ventilator free days (VFDs) in the first 28 days following injury, length of ICU and hospital stay, and general health outcomes (SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores). Categorical variables are reported as frequency counts and percentages and the two groups were compared using Fisher's Exact test. Continuous data are reported as median and interquartile range and the two groups were compared using the Wilcoxon rank-sum test. From the original cohort of 207 patients, 108 had been treated surgically and had data available on the type of plate construct used. Fifty-nine patients (55%) had received fixation with non-locking plates (primarily 3.5 or 2.7 mm pelvic reconstruction plates) and 49 (45%) had received fixation with locking plates (primarily rib-specific locking plates). The two groups were similar in regard to baseline and injury characteristics. In the non-locking group, 15% of patients (9/59) had evidence of hardware loosening versus 4% (2/49 patients) in the locking group (p = 0.1). The rate of re-operation for hardware complications was 3% in the non-locking group versus 0% in the locking group (p = 0.5). No patients in either group required revision fixation for loss of reduction or nonunion. There were no differences between the groups with regard to VFDs (26.3 [19.6 – 28] vs. 27.3 [18.3 – 28], p = 0.83), length of ICU stay (6.5 [2.0 – 13.1] vs 4.1 [0 – 11], p = 0.12), length of hospital stay (17 [10 – 32] vs. 17 [10 – 24], p = 0.94) or SF-36 PCS (40.9 [33.6 – 51.0] vs 43.4 [34.1 – 49.6], p = 0.93) or MCS scores (47.8 [36.9 – 57.9] vs 46.9 [40.5 – 57.4], p = 0.95). We found no statistically significant differences in outcomes between patients who received surgical stabilization of their unstable chest wall injury when comparing non-locking plates versus locking plates. However, the rate of hardware loosening was nearly 4 times higher in the non-locking plate group and trended towards statistical significance, although re-operation related to this was less frequent. This finding is not surprising, given the inherent challenges of rib fixation including thin bones, comminution, potential osteopenia and a post-operative environment of constant motion. We believe that the increased cost of locking plate fixation in this setting is likely justifiable given these findings

Aim. Squamous cell carcinoma (SCC) is a rare but often devastating complication of chronic osteomyelitis. Optimum diagnosis and management are not well established. This paper aimed to develop a definitive, evidence-based approach to its diagnosis and management. Method. A systematic review of relevant published studies available in English from 1999-present was conducted. Strict inclusion criteria ensured that the diagnoses of osteomyelitis and SCC were explicit and valid. Additional cases from our institution were included using the same eligibility criteria. Data regarding patient demographics, osteomyelitis diagnosis, SCC diagnosis and its management and patient outcomes were collected. Statistical significance was assessed by Fisher's exact test. Results. Nineteen publications involving 98 patients plus eight patients managed locally were included. Eighty percent of patients were male, diagnosed with SCC at an average age of 59 years old (24–82 years), 31 years after their osteomyelitis diagnosis (3–67 years). Multiple bones were affected: tibia or fibula (59%), femur (17%), pelvis and sacrum (8%), bones of the foot and ankle (8%) and upper limbs (6%). Malignant transformation was associated predominantly with sinus (82%), ulceration (61%) and discharge (41%). SCC was diagnosed by biopsy (77%) or incidentally (23%) following definitive management for osteomyelitis. Twenty-two percent of patients had a staging CT scan. Seventy-six percent of patients underwent amputation, 16% underwent limb-sparing wide local excision and the remaining patients were palliated. Incidental diagnosis of SCC was associated with poorer outcomes in terms of death or disease recurrence (one year, p=0.052, five years p=0.021, Fisher's exact test) as was metastatic disease at SCC diagnosis (one year, p=0.006, five years, p=0.032, Fisher's exact test) and pelvic or sacral disease (one year p<0.001, five years p=0.002, Fisher's exact test). All patients who were not actively treated died within one year of SCC diagnosis. Data was suggestive that more patients who underwent amputation (versus wide local excision) were disease free at one and five years, but this was not statistically significant (one year, p=0.058, five years, p= 0.152, Fisher's exact test). Conclusions. SCC should be suspected in all cases of chronic osteomyelitis with skin changes, particularly where changes exceed 3 years duration and involve the pelvis. Multiple biopsies for histology should be taken in all suspected cases, as well as routinely during surgical excision of osteomyelitis when chronic skin changes are present. Once SCC is identified, staging CT scan should be performed to guide management. Amputation, where possible, should be considered

Frailty has been shown to be a risk predictor for peri-operative adverse events (AEs) in patients undergoing various type of spine surgery. However, its relationship with Patient Related Outcome Measures (PROMS) remains unknown. The primary objective of this study was to determine the impact of frailty on PROMS in patients undergoing surgery for thoraco-lumbar degenerative conditions. The secondary objective was to determine the association between frailty and baseline PROMS. This is a retrospective study of a prospective cohort of patients >55 years old who underwent surgery between 2012 and 2018. Patient data and PROMS (EQ-5D, SF-12, ODI, back and leg pain NRS) were extracted from the Canadian Spine Outcomes and Research Network registry for a single academic centre. Frailty was retrospectively calculated using the modified frailty index (mFI) and patient were classified as frail, pre-frail and non-frail. Patient characteristics and outcomes were analyzed using ANOVA or Kruskal-Wallis test for continuous variables and Chi square or Fisher's exact test for proportions. A generalized estimating equations (GEEs) regression model was used to assess the association between patients' baseline frailty status and PROMs measures at three and 12 months. 293 patients were included with a mean age of 67 ± 7 years. Twenty-two percent of the patients (n= 65) were frail, 59 % (n=172) were pre-frail and 19% (n=56) were non-frail. At baseline, the three groups had similar PROMS, except for the PCS which was worse in the frail group (mean difference [95% CI], −4.9 [−8.6;-1.1], p= 0.0083). The improvement in the EQ-5D, PCS, MCS, ODI, back and leg pain NRS scores was not significantly different between the three groups (p> 0.05). The was no difference in the evolution of the PROMS at three and 12 months between the three groups (p> 0.05). Although frailty is a known predictor of AEs, it does not predict worse PROMS after spine surgery in that population. At baseline, non-frail, pre-frail and frail patients have similar PROMS

Aim. Kingella kingae seems to be the most common cause of osteoarticular infections (OAI) in children under 48 months of age (1). Recent studies had shown that K. kingae is poorly susceptible to anti-staphylococcal penicillin and some isolates produce beta-lactamase (2). This led to the need for new treatment guidelines for OAI in populations in which K. kingae is frequent. Our study aimed to design a model which could predict K. kingae OAI in order to initiate appropriate empirical treatment on hospital admission. Method. We performed a retrospective cohort study in children from 1 month to 15 years old diagnosed with OAI, hospitalized between 2006 and 2018. Mann-Whitney test and Fisher's exact test were used for data analysis. The model predicting K. kingae OAI was designed using logistic regression. Results. 247 children were included in the study, 126 (51%) had osteomyelitis (OM), 83 (33.6%) septic arthritis (SA) and 38 (15.4%) combined OM and SA. The median age was 52 (IQR 20–122) months, male-to-female ratio was 1.57:1. Pathogens were isolated in 101 (40.9%) cases with the following frequency: Staphylococcus aureus (n=59), K. kingae (n=13), Streptococcus pyogenes (n=11), Streptococcus pneumoniae (n=8). Patients with K. kingae OAI had lower CRP levels compared to other pathogens (p<0.05). WBC was higher compared to S. aureus OAI (p=0.011), children with K. kingae OAI were younger than children infected with S. aureus (p<0.001) and S. pyogenes (p=0.003). Based on this information we designed a predictive model using previous parameters as predictors of outcomes. The model had a 92.3% sensitivity and a 77.5% specificity. Then, we tried to test the model's predictive power based on the treatment failure of empirical anti-staphylococcal antibiotics in the group of children with OAI without the known pathogen. In the subgroup for which the model predicted K. kingae OAI, antibiotic treatment had to be changed in 6/59 cases. It had to be changed in only 1/83 cases in the non-K. kingae group (p=0.021). Conclusions. Despite poor specificity of the model, we found it to be more important to include all K. kingae OAI, that can be then properly treated. Additionally, with good specificity we acquire good negative predictive value, which means that children, for whom the model did not predict K. kingae OAI, can be safely treated with anti-staphylococcal penicillin

Introduction. External fixators are attached to bones with percutaneous pins and wires inserted through soft tissues and bone increasing the risk of infections. Such infections compromise patient outcomes e.g., through pin loosening or loss, failure of fixator to stabilise the fracture, additional surgery, increased pain, and delayed mobilisation. These infections also impact the healthcare system for example, increased OPD visits, hospitalisations, treatments, surgeries and costs. Nurses have a responsibility in the care and management of patients with external fixators and ultimately in the prevention of pin-site infection. Yet, evidence on best practices in the prevention of pin-site infection is limited and variation in pin-site management practices is evident. Various strategies are used for the prevention of pin-site infection including the use of different types of non-medicated and medicated wound dressings. The aim of this retrospective study was to investigate the use of dry gauze or iodine tulle dressings for the prevention of pin-site infections in patients with lower limb external fixators. Methodology. A retrospective study of patients with lower limb external fixators who attended the research site between 2015–2022. Setting & Sample: The setting was the outpatient's (OPD) orthopaedic clinic in a University Teaching Hospital in Dublin, Ireland. Eligibility Criteria:. Over the age of 16, treated with an Ilizarov, Taylor Spatial frame (TSF) or Limb Reconstruction System (LRS) external fixators on lower limbs,. Pin-sites dressed with dry gauze or iodine tulle,. Those with pre-existing infected wounds close to the pin site and/or were on long term antibiotics were excluded. Follow Up Period: From time of external fixator application to first pin-site infection or removal of external fixator. Outcome Assessment: The primary outcome was pin-site infection, secondary outcomes included but were not limited to frequency of pin-site infection according to types of bone fixation, frequency of pin/wire removal and hospitalisation due to infection. Data analysis: IBM SPSS Version 25 was used for statistical analysis. Descriptive and inferential statistics were conducted as appropriate. Categorical data were analysed by counting the frequencies (number and percentages) of participants with an event as opposed to counting the number of episodes for each event. Differences between groups were analysed using Chi-square test or Fisher's exact test, where appropriate. Continuous variables were reported using mean and standard deviations and difference analysed using a two-sample independent t-test or non-parametric test (Mann-Whitney), where appropriate. Using Kaplan-Meier, survival analysis explored time to development of infection. Ethical approval: granted by local institute Research Ethics Committee on 12th March 2018. Results. During the study period, 97 lower limb external fixators were applied with 43 patients meeting the study eligibility criteria. The mean age was 38 (SD 14.1; median 37) and the majority male (n=32, 74%). At least 50% (n=25) of participants had an IIizarov fixator, with 56% (n=24) of all fixators applied to the tibia and fibula. Pin/wire sites were dressed using iodine (n=26, 61%) or dry gauze dressings (n=15, 35%). The mean age of participants in the iodine group was significantly higher than the dry gauze group (p=.012). The only significant difference between the iodine and dry gauze dressing groups at baseline was age. A total of 30 (70%) participants developed a pin-site infection with 26% (n=11) classified as grade 2 infection. Clinical presentation included redness (n=18, 42%), discharge (n=16, 37%) and pain (n=15, 35%). Over half of participants were prescribed oral antibiotics (n=28, 65%); one required intravenous antibiotics and hospitalization due to pin-site infection. Ten (23%) participants required removal of pin/wires; two due to pin-site infection. There was no association between baseline data and pin-site infection. The median time to developing an infection was 7 weeks (95%, CI 2.7 to 11.29). Overall, there were 21 (81%, n=26) pin-site infections in the iodine group and nine (60%, n=15) in the dry gauze group, difference in proportion and relative risk between the dressing groups were not statistically significant (RR 1.35, 95% CI 0.86–2.12; p= .272). There was no association between baseline data, pin-site infection, and type of dressing. Conclusions. At the research site, patients are referred to the OPD orthopaedic clinic from internal and external clinical sites e.g., from Hospital Consultants, General Practitioners and occasionally from multidisciplinary teams, throughout Ireland. Our retrospective observation study found that 97 lower limb external fixators were applied over a seven-year period which is lower than that reported in the literature. However, the study period included the COVID pandemic years (2020 and 2021) which saw a lower number of external fixators applied due to lack of theatre availability, cancelled admissions and social/travel restrictions that resulted in fewer accidents and lower limb trauma cases requiring external fixator application. The study highlighted a high infection rate with 70% of participants developing pin-site infection which is in keeping with findings reporting in other studies. Our study showed that neither an iodine nor dry gauze dressing was successful in preventing pin-site infection. In the iodine group 81% of participants developed infection compared to 60% in the dry gauze group. Given the lack of difference between the two groups consideration needs to be given to the continued use of iodine dressings in the prevention of pin-site infection. Pin-site infections result in a high portion of participants being prescribed antibiotics and, in an era, that stresses the importance of antimicrobial stewardship there is a need to implement effective infection prevention and control strategies that minimise infection. Further research is therefore needed to investigate more innovative medicated dressings such as those that contain anti-microbial or anti-bacterial agents

Introduction. The purpose of this study was to characterize the recovery of physical activity following knee arthroplasty by means of step counts and flight counts (flights of stairs) measured using a smartphone-based care platform. Methods. This is a secondary data analysis on the treatment cohort of a multicenter prospective trial evaluating the use of a smartphone-based care platform for primary total and unicondylar joint arthroplasty. Participants in the treatment arm that underwent primary total or unicondylar knee arthroplasty and had at least 3 months of follow-up were included (n=367). Participants were provided the app with an associated smart watch for measuring several different health measures including daily step and flight counts. These measures were monitored preoperatively, and the following postoperative intervals were selected for review: 2–4 days, 1 month, 1.5 month, 3 months and 6 months. The data are presented as mean, standard deviation, median, and interquartile range (IQR). Signed rank tests were used to assess the difference in average of daily step counts over time. As not all patients reported having multiple stairs at home, a separate analysis was also performed on average flights of stairs (n=214). A sub-study was performed to evaluate patients who returned to preoperative levels at 1.5 months (step count) and 3 months (flight count) using an independent samples T test or Fisher's Exact test was to compare demographics between patients that returned to preoperative levels and those that did not. Results. The mean age of the step count population was 63.1 ± 8.3 years and 64.31% were female, 35.69% were male. The mean body mass index was 31.1 ± 5.9 kg/m. 2. For those who reported multiple stairs at home, the mean age was 62.6 ± 8.3 years and 62.3% were female. The mean body mass index was 30.7 ± 5.4 kg/m. 2. . As expected, the immediate post-op (2–4 days) step count (median 1257.5 steps, IQR 523 – 2267) was significantly lower than preop (median 4160 steps, IQR 2669 – 6034, p < 0.001). Approximately 50% of patients returned to preoperative step counts by 1.5 months postoperatively with a median 4,504 steps (IQR, 2711, 6121, p=0.8230, Figure 1). Improvements in step count continued throughout the remainder of follow-up with the 6-month follow-up visit (median 5517 steps, IQR 3888 – 7279) showing the greatest magnitude (p<0.001). In patients who reported stairs in their homes, approximately 64% of subjects returned to pre-op flight counts by 3 months (p=0.085), followed similar trends with significant improvements at 6 months (p=0.003). Finally, there was no difference in age, sex, BMI, or operative knee between those that returned to mean preoperative step or flight counts by 1.5 months and 3 months, respectively. Discussion and Conclusion. These data demonstrated a recovery curve similar to previously reported curves for patient reported outcome measures in the arthroplasty arena. Patients and surgeons may use this information to help set goals for recovery following total and unicondylar knee arthroplasty using objective activity measures. For any figures or tables, please contact the authors directly

The purpose of this study was to quantify tibial tunnel enlargement at 3-, 6- and 12-months post-anterior cruciate ligament reconstruction (ACLR), and evaluate the magnitude of tunnel widening with use of a Poly (L-lactic Acid) interference screw (PLLA (Bioscrew XtraLok, Conmed, New York)) compared to a Poly (L-lactic Acid) + tricalcium phosphate interference screw (PLLA+TCP (GENESYS Matryx screw comprised of microTCP and 96L/4D PLA, Conmed, New York)). This was a prospective randomized controlled trial with two parallel groups. Eighty unilateral ACL-deficient participants awaiting ACLR surgery were recruited between 2013 and 2017 from the clinic of a sole fellowship trained orthopaedic surgeon. Patients had to be skeletally mature and less than 45 years old, with no concomitant knee ligament injuries requiring surgery, chondromalacia, or previous history of ipsilateral knee joint pathology, surgery or trauma to the knee. Participants were randomized intra-operatively into either the PLLA or PLLA+TCP tibial interference screw fixation group. Study time points were pre-, 3-, 6-, and 12-months post ACLR. Participants underwent x-rays with a 25 mm calibration ball, IKDC knee assessment, and completed the ACL-Quality of Life score (ACL-QOL) at each visit. Measurement (mm) of the most proximal and distal extents as well as the widest point of the tibial tunnel were taken using efilm (IBM Watson Health) and were standardized relative to the calibration ball. A contrast inverter was used to determine clear borders based on contrast between normal and drilled bone. In addition, a subjective evaluation of the tunnel was conducted looking for bowing of the borders of the tunnel or change in tunnel shape, categorizing the tunnel as widened or not widened. Differences between groups at each time point were evaluated using independent t-tests corrected for multiple comparisons. Tunnel width was also compared as a percentage of actual screw size at 12-months post-operative. Categorical data were compared using Fisher's Exact Test. Forty participants were randomized to each group with mean age (SD) of 29.7 (7.6) and 29.8 (9.1), for PLLA and PLLA+TCP, respectively. There were no differences between groups in age, gender or ACL-QOL. There were no differences found between groups at any time point in either tunnel width measurements or tunnel width as a percentage of actual screw size. The greatest difference between groups was noted in the measurement of the widest point on lateral x-ray view with a mean difference of 11%. Based on subjective evaluation of tunnel shape, three participants had visible widening in the PLLA group, and two in the PLLA+TCP group (p=NS). No differences in tunnel widening were identified between ACL reconstruction patients using a PLLA interference screw compared to a PLLA+TCP screw for tibial fixation up to 12-months post-operative

Aim. Surgical and antimicrobial treatment of periprosthetic joint infections (PJI) depends largely on the causative pathogen. We assessed the pathogen detection rates and the concordance of preoperative synovial fluid culture and culture of intraoperative samples harvested during revision surgery in patients with PJI. Method. Culture-positive PJI cases treated at our institution from 02/2011 to 07/2018, for which culture results from preoperative (synovial fluid) and intraoperative samples (periprosthetic tissue, synovial or sonication fluid) were available, were retrospectively assessed. For organisms belonging to the resident skin flora (coagulase-negative staphylococci, cutibacteria and corynebacteria) significant growth was considered, if the identical pathogen grew in ≥2 samples or >50 cfu/ml sonication fluid. For other pathogens (S. aureus, streptococci, enterococci, fungi and gram-negative rods) or patients under antimicrobials, any growth was considered positive. We determined the pathogen detection rate in preoperative and intraoperative cultures and compared it in different subgroups using Fisher's exact test. Furthermore, we assessed the concordance of preoperative and intraoperative cultures. Results. We included 167 culture-positive PJI cases (76 hip and 91 knee joints). Coagulase-negative staphylococci (n=55, 33%), Staphylococcus aureus (n=34, 20%) and streptococci (n=22, 13%) were the most common pathogens. In 17 cases (10%) polymicrobial infection was found. The pathogen(s) grew in synovial fluid in 105 cases and in intraoperative samples in 146 cases (63% vs. 87%, p<0.001). 49 patients received antibiotics before aspiration and/or surgery. No differences were observed comparing hip and knee prostheses, primary and revision prostheses or patients receiving or not receiving antibiotics before sampling. Congruent results of preoperative and intraoperative cultures were found in 85 cases (concordance 51%). In 14 cases (8%), the pathogen was detected preoperatively only, in 59 cases (35%) the pathogen was found intraoperatively only; in 3 cases an additional pathogen was found preoperatively, in 6 cases an additional organism was found intraoperatively. Pathogen detection was significantly better in intraoperative compared to preoperative cultures in low-virulent pathogens (87% vs 36%, p<0.001), polymicrobial infections (88% vs. 47%, p<0.001) and delayed/late PJI (>3months; 92% vs 64%, p<0.001). There was no difference regarding detection rate of high-virulent pathogens (88% vs 83%) and in early postoperative PJI (<3 months, 91% vs. 73%). Conclusions. As concordance of preoperative and intraoperative microbiological results was 51%, surgical and antimicrobial treatment should not be selected based on preoperative synovial fluid cultures only. An additional pathogen was found intraoperatively in 39%

INTRODUCTION. Interest in tissue-preserving or minimally invasive total hip arthroplasty (THA) is increasing with focus toward decreased hospital stay, enhanced rehabilitation, and quicker recovery for patients. Two tissue-preserving techniques, the anterior and superior approaches to THA, have excellent clinical results, but little is known about their relative impact on soft tissue. The purpose of this study was to evaluate the type and extent of tissue damage after THA with each approach, focusing on abductors, short external rotators, and the hip capsule. METHODS. Total hip arthroplasty was performed on bilateral hips of eleven fresh-frozen cadavers (22 hips). They were randomized to anterior THA performed on one side and superior THA performed on the other, in the senior authors' standard technique. Two independent examiners graded the location and extent of tissue injury by performing postsurgical dissections. Muscle bellies, tendons, and capsular attachments were graded as intact, split, damaged (insignificant, minimal, moderate, or extensive damage), or detached based on direct visual inspection of each structure. Tissue injury was analyzed with either a chi-squared (≥5 qualifying structures) or Fisher's exact test (<5 qualifying structures). P values <0.05 were significant. RESULTS. The abductor muscles or tendons were intact or insignificantly damaged in 63.6% of anterior approach specimens compared with 84.1% of the superior specimens (p= 0.03). Specifically, the gluteus minimus tendon had moderate or extensive damage in 63.6% of anterior specimens compared with none of the superior specimens (p <0.01). Short external rotators (SERs) group, defined as both the muscle and tendon of the piriformis, conjoint, obturator externus, and quadratus, were intact or insignificantly damaged in 63.6% of anterior approach specimens compared with 80.5% of the SER group of superior specimens (p = 0.02). The femoral attachments of the anterior, posterior, and superior capsules were extensively damaged or detached in 90.9%, 81.8%, and 100% of anterior approach specimens respectively compared with 0%, 9.1% and 9.1% of superior approach specimens respectively (all p <0.01). CONCLUSION. In a cadaveric study examining superior and anterior approaches to THA, the superior approach demonstrated significantly less soft-tissue destruction than the anterior approach, specifically to the gluteus minimus tendon, short external rotators, and the hip capsule

Aim. Prosthetic joint infection (PJI) is a major complication in THA. Nasal carriage with S. Aureus is a well-defined risk factor for infection in hospitalized patients. Risk for infection is reduced up to 50% by eradication therapy. Since PJI rates are very low and only 25% of the population are carriers, significant differences are hard to show and reports on PJI have been inconclusive. We analysed the effect of S. Aureus eradication therapy in THA. Methods. From 2011, patients receiving THA are screened for S. Aureus carriage and carriers are treated. This group was retrospectively compared with a historical THA group in which no screening and eradication therapy was done. We assumed similar carrier rates in both groups and calculated the risk reduction of eradication therapy for PJI in comparison to the historical carriers without treatment. Fisher's Exact test was used to compare outcome. Results. 2072 patients were screened and 478 patients were positive (23%). The historical control group consisted of 1248 patients, with 288 calculated carriers (23%). 15 PJI (0.72%) occurred vs 14 (1.12%) in the historical group (p=0.16). A 52% reduction in S. Aureus infections was found (0.33% vs 0.64% p=0.15). Infection rates for PJI caused by S. aureus was similar in non-carriers and carriers after eradication therapy (0.3 vs 0.4% p=0.506). The calculated infection rates in carriers in the historical group was reduced from 2.6% to 0.8% (RR 3,25, p=0.07) by eradication therapy and from 1.7% to 0,4% (RR 4,25, p=0.07) for S. Aureus PJI. Conclusions. A clear trend in reduction of PJI was demonstrated as a result of S. aureus screening and eradication therapy, reducing the rate of PJI for carriers to the same level as non-carriers

Instability after total hip arthroplasty is the most common indication for revision arthroplasty and can be difficult to treat. The purpose of this study is to evaluate the outcomes associated with the use of a constrained acetabular component as a treatment for instability after hip arthroplasty. We reviewed the clinical and radiographic outcomes of 149 arthroplasties, that had been performed with use of a single design of constrained acetabular component between 2007 and 2012 at a single institution. Patient demographics and case specific data were collected The Mann-Whitney U test was used to assess continuous variables. Categorical variables were examined using the Chi-square test and Fisher's exact test when appropriate. Survival probability was calculated using the Kaplan-Meier method. The mean age at time of index surgery was 70 years, 65% were female, and mean BMI was 26.3. The average number of previous surgeries was 3.6. The constrained liner was cemented into a well-fixed cup in 40 hips (20%). In eighty-two (55%) hips the constrained component was implanted for the treatment of recurrent instability, and in sixty-seven (45%) hips it was implanted because the hips demonstrate instability during revision surgery. At an average duration of follow-up of 4.2 (2–7) years the overall revision rate was 10.6 % The constrained acetabular device eliminated or prevented hip instability in all patients except five; 3.3% had a new dislocation and six (4.0%) had failure of the retentive ring. Three revisions (2%) were performed for deep infection, and 2 (1.3%) for acetabular component loosening. Radiographic analysis revealed a non-progressive radiolucent line around the cup in 19 hips (12.7%). When stratified by patient age, survivorship for patients less than 65 years of age versus those greater than 65 years was similar. This study correlates with results of other papers in the literature looking at outcome of constrained tripolar type sockets. The focal constraint socket with a metal ring type design has a much greater failure rate (9–29%). Constrained liners remain an excellent option for hip instability in early to mid- term follow up