Background. Increasing number of studies investigating surgical patients have reported longer length of stay (LOS) in hospital after an operation with higher ASA grades. However, the impact of Body Mass Index (BMI) on LOS in hospital post Total Knee Replacement (TKR) remains a controversial topic with conflicting findings in reported literature. In our institution, we recently adopted a weight reduction program requiring all patients with raised BMI to participate in order to be considered for elective TKR. Objectives. This has prompted us to investigate the impact BMI has on LOS compared to the more established impact of ASA grade on patients following Primary TKR. Methods. A retrospective analysis was conducted on all elective primary TKR patients between November 2013 and May 2014. LOS was compared in BMI groups <30, 30–40 and >40 and ASA grades 1–2 and 3–4. ANOVA and independent t-test were used to compare mean LOS between BMI groups and ASA grades, respectively. Results. Two hundred and thirty six TKR were analysed. Mean LOS in BMI groups <30, 30–40 and >40 were 6.0, 6.4 and 6.0 days, respectively (p = 0.71). Mean LOS in ASA groups 1–2 and 3–4 were 5.8 and 7.6, respectively (p < 0.01). Conclusions. In patients undergoing primary TKR, ASA grade is a better predictor of LOS than BMI. Our data further adds to the evidence that high BMI alone is not a significant factor in prolonging LOS after a primary TKR. This should be taken into account when allocating resources to optimise patients for surgery. Level of evidence. III - Evidence from case, correlation, and comparative studies

Introduction. More than 60% of patients presenting with a hip fracture have significant medical co-morbidities and a one year mortality rate between 14% and 47%. The rating scale for the American Society of Anaesthetists (ASA) is a reliable predictor of both surgical risk and mortality with ASA 4 patients having 100% mortality at one year.1,2. Aims. Our aim was to establish a mortality rate for fractured neck of femur patients at three months and twelve months, and to ascertain the mortality of patients with an ASA 4 grading. Ultimately, should we be operating on this high risk cohort of patients'. We also chose to analyse our current practice in the management of displaced intracapsular neck of femur fractures in patients 90 years of age and over. Methods. Over 300 patients with a fractured neck of femur were identified between the 1st January 2007 and the 1st January 2008. A retrospective case note review of 151 patients was performed in conjunction with the NHS mortality database to establish whether each patient was alive or deceased. Our findings were compared to the standards set which included an overall mortality of 20% at three months, 30% at twelve months and 100% mortality for ASA 4 patients at twelve months. Results. Five patients were excluded from the study as one patient had incomplete data and four patients died prior to intended surgery. Only one of these patients had an ASA 4 grading. 146 patients were included and 23 patients (15.7%) were ASA 4. The overall mortality was 16% at three months and 23% at twelve months which was within the limits of the standards set. ASA 4 patients had a mortality of 57% at three months and 65% at twelve months which compared favourably with the limited literature available. There were 11 patients who were 90 years of age and over with intracapsular neck of femur fractures. Three of these patients were treated with a cemented hemiarthroplasty and were all alive at twelve months. Conclusions. Our study demonstrates a much better mortality rate in the ASA 4 patients than the limited literature available would suggest. We believe that ASA 4 patients should continue to be offered surgical intervention and that this data provides us with information to allow the patient and family to reach an informed decision with regard to their treatment. Intracapsular neck of femur fractures in patients 90 years of age and over can be treated with a cemented hemiarthroplasty provided they are deemed fit

A number of studies have reported longer length of hospital stay (LOS) after surgery in patients with higher ASA grades. The impact of Body Mass Index (BMI) on LOS after Total Hip Replacement (THR) remains unclear with conflicting findings in reported literature. In our hospital we strongly encourage all patients with a raised BMI to participate in a weight reduction programme prior to surgery. This prompted us to investigate the impact BMI has on LOS compared to the more established impact of ASA grade. A retrospective analysis was conducted on all elective primary THR patients between 11/2013 to 02/2014. LOS in BMI groups <30, 30–39 and ≥40 and ASA grades 1–2 and 3–4 was compared. Where appropriate, independent t-test and non-parametric Mann-Whitney test were used to predict significance. 122 THR were analysed. Mean LOS in BMI groups <30, 30–39 and ≥40 were 5.6, 6.2 and 8.0 days, respectively. This was not predicted significant (p=0.7). Mean LOS in ASA groups 1–2 and 3–4 were 5.2 and 9.3, respectively. This was predicted significant (p-value < 0.01). In patients undergoing primary THR, ASA grade is a better predictor of LOS than BMI. Our data adds to the evidence that high BMI alone is not a significant factor in prolonging LOS after a primary THR. This should be taken into account when allocating resources to optimise patients for surgery

Introduction: The American Society of Anesthesiologists (ASA) grade is supposed to accurately predict morbidity and mortality. We wanted to better inform our patients of their risk of mortality in elective operations. Method: Analysis of data from Galen (Theatre management software) routinely gathered as part of the preoperative assessment of patients. We linked this to the Date of Death field in the Hospital Master Patient index to identify those patients who had died within 90 days of surgery, including deaths after discharge from hospital. Results: Two thousand and thirty one patients over two years. These were elective Orthopaedic operations including knee (1074) and hip (957) replacements, both primary and revision. There were thirty one mortalities over a two year period. Sixteen mortalities for knee (1.5% of knee operations) and 15 for hip surgery (1.6% of hip operations). Respective mortality for ASA grades 1–4 are presented in table below. Discussion: Our review of the 2031 patients shows that the relative risk of mortality between ASA grades 1–4 increased from 1–8.8. We examined the notes because grade 4’s mortality was 10% and realized that 75% of ASA grades recorded by Orthopaedic surgeons and anaesthetists differed. The anaesthetists seem to down grade the ASA 4’s. Conclusion: The relative risk of mortality is lower than that as previously described. Orthopaedic surgeons seem to assess patient better when it comes to ASA grading. The paper further discusses the implications of these conclusions

Abstract. Introduction. Medial fix bearing unicompartmental knee replacement (UKR) designs are consider safe and effective implants with many registries data and big cohort series showing excellent survivorship and clinical outcome comparable to that reported for the most expensive and surgically challenging medial UKR mobile bearing designs. However, whether all polyethylene tibial components (all-poly) provided comparable results to metal-backed modular components during medial fix bearing UKR remains unclear. There have been previous suggestions that all-poly tibia UKR implants might show unacceptable higher rates of early failure due to tibial component early loosening especially in high body max index (BMI) patients. This study aims to find out the short and long-term survival rate of all-poly tibia UKR and its relationship with implant thickness and patient demographics including sex, age, ASA and BMI. Material and Methods. we present the results of a series of 388 medial fixed bearing all-polly tibia UKR done in our institution by a single surgeon between 2007–2019. Results. We found out excellent implant survival with this all-poly tibia UKR design with 5 years survival rate: 96.42%, 7 years survival rate: 95.33%, and 10 years survival rate: 91.87%. Only 1.28% had early revision within 2 years. Conclusion. Fixed bearing medial all-poly tibia UKR shows excellent survivor rate at 2, 5, 7 and 10 years follow up and the survival rate is not related with sex, age, BMI, ASA grade or implant thickness. Contrary to the popular belief, we found out that only 1.71% of all implants was revised due to implant loosening

INTRODUCTION. Utilization of a patient management support system in our clinical pathway has been successfully demonstrated to both reduce the length of hospital stay after primary THA, as well as reducing the number of hospital readmissions. While successful in a general patient population, the ability of a patient management support system to reduce readmissions in subsets of high risk THA patients has not been evaluated. METHODS. We identified all primary THAs performed at a single institution between 2013 and 2015. Patient sex, age at the time of surgery, race, ASA grade, and 120-day readmissions were retrieved from the patient medical record. Similar to previous studies, the patient's home address was used as a proxy for socioeconomic status, with the estimated median income of a given patient being estimated as the median household income for patients of similar ethnicity living within their zip code as reported in the 2014 U.S. Census. A binary regression was used to determine if a model of patient factors (age, sex, race, socioeconomic status, and/or ASA grade) could accurately predict 120-day readmission after primary THA. Age and socioeconomic status were treated as a continuous variable and all other factors were categorical in nature, and the individual effects of each categorical factor on readmissions were also assessed. RESULTS. A sample of 889 primary THAs was identified using the above criteria, of which 754 (84.8%) were Caucasian and 124 (13.9%) were African Americans. Eleven patients (1.2%) either self-reported a different race or race was unknown. Due to the small number of patients in the other/unknown group, this subset was not included in our analysis. With the remaining sample of 878 THAs (475 females, 403 males; age 62.1 ± 13.0 years), a model containing age, sex, race, socioeconomic status, and ASA grade was unable to accurately predict the need for hospital readmission (R2 = 0.02). When assessed individually, the rates of hospital readmission did not differ by sex or race; however, those with ASA grades I or II had significantly lower readmission rates than patients with ASA grades III or IV (Table 1). DISCUSSION AND CONCLUSION. Despite a comprehensive program, the risk of readmission for patients with greater comorbidity burdens was double that of patients with low ASA grades

Following the recommendation of NICE guidelines (CG124) we have recently started using cemented smooth tapered stem hemiarthroplasty as our standard management of intra-capsular neck of femur fractures. Prior to publication of the above guidelines the standard implant utilised was Thompson Hemiarthroplasty prosthesis. The cost implications of this change have not been fully appreciated and the benefit of these changes in ASA grade 3–4 patients has not previously been analysed. We identified a cohort of 89 patients admitted with displaced intra-capsular neck of femur fracture with an ASA grade 3–4. These underwent hip hemiarthroplaties at our centre over a period of 12 months (before and after guideline implementation). Data regarding in-hospital mortality, dislocation, reoperation and place of discharge were retrospectively collected and analysed. Our cohort included 46 patients who underwent a Thompsons Hemiarthroplasty, 30 patients who had a cemented smooth tapered stem hemiarthroplasty and 13 patients who had an Austin-moore Hemiarthroplasty. In-patient mortality rates were highest in the Austin-moore group, followed by the Thompsons group compared to none in the smooth tapered stem group. However, this was not statistically significant. One patient in the Thompsons group and one patient in the smooth tapered group had multiple dislocations and re-operations, compared with none in the Austin-moore group. In terms of percentage of patients who were discharged home from hospital the smooth tapered stem group had a percentage that was more than twice that of the Thompson's which was in turn higher than that found in the Austin-moore group. In conclusion, our data suggests that in patients with an ASA grade of 3–4 there is no significant benefit from using cemented smooth tapper stems when performing a Hip Hemiarthroplasty compared with a well performed Thompsons and that the cost savings of this is significant. We accept that our current numbers are relatively small and further work is needed

There is mixed evidence in the literature regarding increasing age, ASA and BMI as risk factors for surgical site infection in orthopaedic surgery. To investigate the matter further, we examined 1055 wounds in 1008 patients in the Department of Trauma and Orthopaedic Surgery at University College London Hospital between 2000 and 2006. All patients with a minimum two-night stay were included. Data was collected by four designated research nurses. The age, height, weight and ASA status of each patient was recorded. All wounds were classified using ASEPSIS. This is a quantitative wound scoring method which is a summation of scores calculated from visual wound characteristics and the clinical consequences of infection. Our results showed a strong linear association between age and ASEPSIS scores. Single variable regression analysis showed a t value of 3.32 and p value of 0.001. A similar linear association was seen between ASA grading and ASEPSIS scores. Single variable regression analysis showed a t value of 2.75 and p value of 0.006. The association between BMI and ASEPSIS scores was markedly different from that seen with age and ASA. The graph was U-shaped with patients with a BMI of 25-30 having the lowest average ASEPSIS scores. Patients with a lower and a higher BMI had higher average ASEPSIS scores. Single variable regression analysis was not significant since the relationship between BMI and ASEPSIS scores is not linear. In conclusion, there are clearly defined patient groups who are at increased risk of developing a surgical site infection: older patients, patients with a higher ASA, and patients with both a low and high BMI. These patients should be targeted to reduce overall infection rates. This can be achieved by ensuring adequate antibiotic prophylaxis, having a low threshold to treat suspected infection and arranging regular follow-up

Introduction. We conducted a study of 312 patients undergoing primary hip and knee arthroplasty in 2005. The aim was to identify the correlation between length of stay, ASA (American society of Anaesthesiologist) grade and BMI (Body Mass Index). Method and materials. 312 patients underwent hip and knee arthroplasty in 2005. ASA grade for surgery was documented by the anaesthetist and BMI by the nurses. 67 patients had inadequate documentation. SPSS software was used for analysis. Results. Of the 245 patients; 35 had ASA grade 1, 144 had ASA grade 2, 64 had ASA grade 3 and 2 had ASA grade 4. Mean length of stay for ASA grade 1 was 6.8 days, ASA grade 2 was 9.75 days, ASA grade 3 was 12.5 days and ASA grade 4 was 13.5 days. There was significant positive correlation (p < 0.01) between the ASA grade and post-operative length of stay. BMI was graded as I (<18.5), II (18.5-24.9), III (25-29.9) and IV (>30). There was no correlation (Pearson's correlation coefficient = 0.184) between BMI and post-operative length of stay. Conclusion. As the ASA grade increases the length of stay in hospital increases. ‘Cherry picking’ of ASA grade I and II patients by the ISTC will increase the average length of stay in NHS hospitals resulting in increased cost. Length of stay on its own is not a good indicator of hospital performance

We report the general mortality rate after total knee replacement and identify independent predictors of survival. We studied 2428 patients: there were 1127 men (46%) and 1301 (54%) women with a mean age of 69.3 years (28 to 94). Patients were allocated a predicted life expectancy based on their age and gender. There were 223 deaths during the study period. This represented an overall survivorship of 99% (95% confidence interval (CI) 98 to 99) at one year, 90% (95% CI 89 to 92) at five years, and 84% (95% CI 82 to 86) at ten years. There was no difference in survival by gender. A greater mortality rate was associated with increasing age (p < 0.001), American Society of Anesthesiologists (ASA) grade (p < 0.001), smoking (p < 0.001), body mass index (BMI) <  20 kg/m. 2. (p < 0.001) and rheumatoid arthritis (p < 0.001). Multivariate modelling confirmed the independent effect of age, ASA grade, BMI, and rheumatoid disease on mortality. Based on the predicted average mortality, 114 patients were predicted to have died, whereas 217 actually died. This resulted in an overall excess standardised mortality ratio of 1.90. Patient mortality after TKR is predicted by their demographics: these could be used to assign an individual mortality risk after surgery

Introduction: Four randomized, double-blind phase III studies (RECORD1–4) investigated the oral, direct Factor Xa inhibitor rivaroxaban for the prevention of venous thromboembolism (VTE) after elective total hip and total knee arthroplasty (THA and TKA). Patients (N=12,729) were randomized to receive oral rivaroxaban 10 mg once daily, or subcutaneous enoxaparin 40 mg once daily (RECORD1–3), or 30 mg twice daily (RECORD4). Those undergoing THA received rivaroxaban or enoxaparin for 31–39 days in RECORD1, and rivaroxaban for 31–39 days or enoxaparin for 10–14 days followed by placebo in RECORD2. In RECORD3 and 4 (TKA), prophylaxis was for 10–14 days. Methods: A prespecified pooled analysis of all four studies evaluated the effect of rivaroxaban on the composite of symptomatic VTE and all-cause mortality, and bleeding, relative to enoxaparin. The present subgroup analysis investigated potential drug–drug interactions with concomitant non-steroidal anti-inflammatory drugs (NSAIDs) or acetylsalicylic acid (ASA) – commonly used pain medications known to affect bleeding risk. The risk of on-treatment bleeding in the total study duration pool of all four RECORD studies was investigated. These prespecified analyses focused on on-treatment, adjudicated bleeding events, any bleeding, and the composite of major bleeding and clinically relevant non-major bleeding – after the first tablet intake (rivaroxaban or matching placebo). Co-medication use was evaluated over time. Relative bleeding rates with and without co-medication were calculated separately for the rivaroxaban and enoxaparin/placebo groups. Time after surgery (day of surgery was day 1) was stratified into three periods (days 1–3, days 4–7 and day 7 up to 2 days after the last dose), based on the decreasing risk with time of a first bleeding event after surgery and because prevalence of co-medication use can vary over time. Bleeding rates were recorded for each time period over the at-risk period (the day of surgery until the last day of double-blind study medication intake +2 days or until initial event onset). The ratio of the bleeding rate for co-medication exposed vs unexposed patient-days in the rivaroxaban group was compared with the corresponding rate ratio for the enoxaparin/placebo group for bleeding events (Mantel–Haenszel methods). Results: Concomitant use of ASA in the rivaroxaban groups showed rate ratios similar to those in the enoxaparin/placebo group (1.32 and 1.40, respectively, for any bleeding). Rate ratios were also similar with concomitant use of NSAIDs (1.22 in both groups, for any bleeding). Conclusion: In the RECORD1–4 subanalysis, there was no indication of increased bleeding associated with the use of these co-medications in patients taking rivaroxaban, compared with enoxaparin

Introduction: Patients presenting with fracture of the femoral neck are usually elderly, and often have extensive co-morbidity. Patients who are considered too unwell for surgery are often keep being delayed until assumed optimised or treated non-operatively. These patients have a high morbidity and mortality and present significant nursing difficulties.

Materials and Methods: We describe a technique of fixation of fracture of the femoral neck under direct infiltration local anaesthesia; that can be performed on the sick elderly patient without the risks associated with general or regional anaesthesia. In a series of twenty eight patients all diagnosed with serious co-morbidity (ASA4) on pre-operative assessment. Twenty three patients suffered from extracapsular fracture neck of femur and five intracapsular fracture neck of femur. All patients were informed about the risks of anesthesia by the senior anesthetist prior to surgery. A mixture of 20 mls n.saline + 20mls of 1% lignocaine with 1:200,000 adrenaline + 20mls 0f.25% plain marcaine (total 60 mls used). This can be increased up to 140 mls in the same ratios.

Results: All patients were operated by various grade registrars. Twenty four (24) DHS and four Hemiarthro-plasty were performed. The patients were all able to complete the surgery using this technique; none required conversion to another form of anaesthesia.

The average duration of surgery was 44 min. All patients survived the procedure and until discharge form hospital.

Discussion: Finlayson and Underhill (1988) suggested that extracapsular fractures are supplied predominantly by the femoral nerve and are therefore more amenable to this type of treatment.

We recommend the consideration of this technique for management of patients with severe co-morbidity and fracture of the femoral neck in order to optimise their chance of survival and avoid the morbidity associated with bed rest.

Hyponatraemia is a potentially preventable post-operative complication following hip arthroplasty. There is a paucity of literature reporting its incidence and guidelines for prevention - unlike AKI which has been prioritised to great success. Hyponatraemia is now rife in elective orthopaedics causing multiple symptoms that delay ambulation and increase the length of hospital stay. We aim to assess the incidence of hyponatraemia and AKI as a benchmark following elective primary total hip arthroplasty (THA), as well as identify patients most at risk in a high volume arthroplasty centre. Between April 2018 and September 2018 all primary THA surgeries performed in one hospital were retrospectively reviewed. Pre-operative and 1 day post operative bloods were analysed. Patients included had normal pre-operative sodium. A total of 221 patients underwent THA. The mean age was 73.6 and ASA 2.1. No patients had a recorded AKI, however 42% of patients had a new post operative hyponatraemia. Of the hyponatraemia cases, 75% were mild, 18% were moderate, and 7% were severe. There was correlation between increased age and increased severity of hyponatraemia. The mean age of patients with mild hyponatraemia was 72.1, moderate was 77.7, and severe was 78.8. An association between ASA and severity of hyponatraemia was noted. In patients who had an ASA of 4 and hyponatraemia, 66% were moderate or severe, ASA 3 was 25%, ASA 2 was 24% and ASA 1 was 0%. The patients who had severe hyponatraemia received on average 3.5L fluid input perioperatively. Rates of post op hyponatraemia are significantly higher than AKI in primary THA. Severity of hyponatraemia increases with age and ASA. Due to its negative outcomes on recovery the high levels of hyponatraemia are worrying. We have identified which patient cohorts are more at risk and recommend more care should be taken in their perioperative fluid balance. It may be beneficial to consider successful AKI prevention and management campaigns and apply them to the prevention of hyponatraemia following hip arthroplasty

Introduction. Neck of femur (NoF) fractures have an inherent 6.5% 30-day mortality as per National hip fracture database(2019). Several studies have demonstrated a higher mortality rate in covid positive NoFs but have been unable to demonstrate whether there are risk factors that contribute to the risk of mortality in this patient group or whether COVID is solely responsible for the higher mortality. Aims. To assess risk factors that are concurrently present in a fracture NoF cohort that may contribute to higher mortality in COVID positive patients. Methods. A cross sectional, retrospective study was performed for a period of 1 year starting from 1st March 2020. All surgically treated neck of femur fracture patients having an isolated intra/extracapsular fracture were included in the study. Data fields recorded- patient demographics, date and time of admission, ward discharge, surgery, mode of surgery (fixation/arthroplasty), prehospital AMTS score, residential status and mobility, ASA grade as per anaesthetist's records, date of death (if deceased), cause of death (as per death certificate/ postmortem / coroner's report). Analysis of mortality was carried out by creating a matched comparison group for each risk factor as well as some combinations. Results. 344 patients were surgically treated for a neck of femur fracture in our DGH during the period of 1st March 2020 to 28th February 2021. 46 patients did not receive a COVID swab (reasons unknown) and were excluded from the study. 35 patients had a COVID-19 RT PCR positive test during their hospital stay and 264 patients remained negative. There were 12 deaths in COVID positive patients (34%) and 53 deaths in COVID negative patients (20%) within the time frame of the study. For each risk factor matched group COVID was seen to confer higher mortality in general. There was no mortality in ASA 1 or 2 patients. Mortality rates in matched groups for age and ASA revealed 23.8% mortality in COVID positive as opposed to 17.3% in COVID negative for ASA 3 and 33.3% mortality in COVID positive vs. 28% in ASA 4. 11 out of the 12 COVID positive patients who died had an AMTS score >6. No correlation was seen between COVID positive deaths and preinjury residential status, type of fracture or surgery offered, or preinjury mobility. The average length of hospital stay was much higher for COVID positive patients (19.5days) as compared to 9.5 days for COVID negative patients. Conclusion. Matched group analysis show that there is a 37.5% increase in COVID positive neck of femur fracture mortality in ASA 3 patients, the same number falls to 17.8% for ASA 4 patients. These figures are much lower compared to other studies in the UK. There is a need to understand the real cause of death in this subset and to improve death certification so that we can differentiate between patients whose mortality is ‘due to’ or ‘With’ COVID

Aims. Unicompartmental knee arthroplasty (UKA) has a higher risk of revision than total knee arthroplasty (TKA), particularly for younger patients. The outcome of knee arthroplasty is typically defined as implant survival or revision incidence after a defined number of years. This can be difficult for patients to conceptualize. We aimed to calculate the ‘lifetime risk’ of revision for UKA as a more meaningful estimate of risk projection over a patient’s remaining lifetime, and to compare this to TKA. Methods. Incidence of revision and mortality for all primary UKAs performed from 1999 to 2019 (n = 13,481) was obtained from the New Zealand Joint Registry (NZJR). Lifetime risk of revision was calculated for patients and stratified by age, sex, and American Society of Anesthesiologists (ASA) grade. Results. The lifetime risk of revision was highest in the youngest age group (46 to 50 years; 40.4%) and decreased sequentially to the oldest (86 to 90 years; 3.7%). Across all age groups, lifetime risk of revision was higher for females (ranging from 4.3% to 43.4% vs males 2.9% to 37.4%) and patients with a higher ASA grade (ASA 3 to 4, ranging from 8.8% to 41.2% vs ASA 1 1.8% to 29.8%). The lifetime risk of revision for UKA was double that of TKA across all age groups (ranging from 3.7% to 40.4% for UKA, and 1.6% to 22.4% for TKA). The higher risk of revision in younger patients was associated with aseptic loosening in both sexes and pain in females. Periprosthetic joint infection (PJI) accounted for 4% of all UKA revisions, in contrast with 27% for TKA; the risk of PJI was higher for males than females for both procedures. Conclusion. Lifetime risk of revision may be a more meaningful measure of arthroplasty outcomes than implant survival at defined time periods. This study highlights the higher lifetime risk of UKA revision for younger patients, females, and those with a higher ASA grade, which can aid with patient counselling prior to UKA. Cite this article: Bone Joint J 2022;104-B(6):672–679

Aims. We aim to evaluate the usefulness of postoperative blood tests by investigating the incidence of abnormal results following total joint replacement (TJR), as well as identifying preoperative risk factors for abnormal blood test results postoperatively, especially pertaining to anaemia and acute kidney injury (AKI). Methods. This is a retrospective cohort study of patients who had elective TJR between January and December 2019 at a tertiary centre. Data gathered included age at time of surgery, sex, BMI, American Society of Anesthesiologists (ASA) grade, preoperative and postoperative laboratory test results, haemoglobin (Hgb), white blood count (WBC), haematocrit (Hct), platelets (Plts), sodium (Na. +. ), potassium (K. +. ), creatinine (Cr), estimated glomerular filtration rate (eGFR), and Ferritin (ug/l). Abnormal blood tests, AKI, electrolyte imbalance, anaemia, transfusion, reoperation, and readmission within one year were reported. Results. The study included 2,721 patients with a mean age of 69 years, of whom 1,266 (46.6%) were male. Abnormal postoperative bloods were identified in 444 (16.3%) patients. We identified age (≥ 65 years), female sex, and ASA grade ≥ III as risk factors for developing abnormal postoperative blood tests. Preoperative haemoglobin (≤ 127 g/dl) and packed cell volume (≤ 0.395 l/l) were noted to be significant risk factors for postoperative anaemia, and potassium (≤ 3.7 mmol/l) was noted to be a significant risk factor for AKI. Conclusion. The costs outweigh the benefits of ordering routine postoperative blood tests in TJR patients. Clinicians should risk-stratify their patients and have a lower threshold for ordering blood tests in patients with abnormal preoperative haemoglobin (≤ 127 g/l), blood loss > 300 ml, chronic kidney disease, ASA grade ≥ III, and clinical concern. Cite this article: Bone Jt Open 2023;4(11):899–905

Aims. Venous thromboembolism (VTE) is a potential complication of foot and ankle surgery. There is a lack of agreement on contributing risk factors and chemical prophylaxis requirements. The primary outcome of this study was to analyze the 90-day incidence of symptomatic VTE and VTE-related mortality in patients undergoing foot and ankle surgery and Achilles tendon (TA) rupture. Secondary aims were to assess the variation in the provision of chemical prophylaxis and risk factors for VTE. Methods. This was a multicentre, prospective national collaborative audit with data collection over nine months for all patients undergoing foot and ankle surgery in an operating theatre or TA rupture treatment, within participating UK hospitals. The association between VTE and thromboprophylaxis was assessed with a univariable logistic regression model. A multivariable logistic regression model was used to identify key predictors for the risk of VTE. Results. A total of 13,569 patients were included from 68 sites. Overall, 11,363 patients were available for analysis: 44.79% were elective (n = 5,090), 42.16% were trauma excluding TA ruptures (n = 4,791), 3.50% were acute diabetic procedures (n = 398), 2.44% were TA ruptures undergoing surgery (n = 277), and 7.10% were TA ruptures treated nonoperatively (n = 807). In total, 11 chemical anticoagulants were recorded, with the most common agent being low-molecular-weight heparin (n = 6,303; 56.79%). A total of 32.71% received no chemical prophylaxis. There were 99 cases of VTE (incidence 0.87% (95% CI 0.71 to 1.06)). VTE-related mortality was 0.03% (95% CI 0.005 to 0.080). Univariable analysis showed that increased age and American Society of Anesthesiologists (ASA) grade had higher odds of VTE, as did having previous cancer, stroke, or history of VTE. On multivariable analysis, the strongest predictors for VTE were the type of foot and ankle procedure and ASA grade. Conclusion. The 90-day incidence of symptomatic VTE and mortality related to VTE is low in foot and ankle surgery and TA management. There was notable variability in the chemical prophylaxis used. The significant risk factors associated with 90-day symptomatic VTE were TA rupture and high ASA grade. Cite this article: Bone Joint J 2024;106-B(11):1249–1256

Traditional radiographic criteria might underestimate or fail to detect subtle types of acetabular dysplasia. Acetabular sector angles (ASA) can measure the degree of anterior and posterior coverage of the femoral head on computed tomography (CT). This study aims to determine ASA values at different axial levels in a cohort of (1) asymptomatic, high-functioning hips without underlying hip pathology (controls); and (2) symptomatic, dysplastic hips that underwent periacetabular osteotomy (PAO). Thereby, we aimed to define CT-based thresholds for hip dysplasia and its subtypes. This is an IRB approved cross-sectional study of 51 high functioning, asymptomatic patients (102 hips) (Oxford Hip Score >43), without signs of osteoarthritis (Tönnis grade≤1), who underwent a CT scan of the pelvis (mean age: 52.1±5.5 years; 52.9% females); and 66 patients (72 hips) with symptomatic hip dysplasia treated with peri-acetabular osteotomy (PAO) (mean age: 29.3±7.3 years; 85.9% females). Anterior and posterior acetabular sector angles (AASA & PASA) were measured by two observers at three CT axial levels to determine equatorial, intermediate, and proximal ASA. Inter- and intra-observer reliability coefficient was high (between 0.882–0.992). Cut-off values for acetabular deficiency were determined based on Receiver Operating Characteristic (ROC) curve analysis, area under the curve (AUC) was calculated. The dysplastic group had significantly smaller ASAs compared to the Control Group, AUC was the highest at the proximal and intermediate PASA. Controls had a mean proximal PASA of 162°±17°, with a cut-off value for dysplasia of 137° (AUC: 0.908). At the intermediate level, the mean PASA of controls was 117°±11°, with a cut-off value of 107° (AUC 0.904). Cut-off for anterior dysplasia was 133° for proximal AASA (AUC 0.859) and 57° for equatorial AASA (AUC 0.868). Cut-off for posterior dysplasia was 102° for intermediate PASA (AUC 0.933). Measurement of ASA on CT is a reliable tool to identify dysplastic hips with high diagnostic accuracy. Posterior ASA less than 137° at the proximal level, and 107° at the intermediate level should alert clinicians of the presence of dysplasia

Aims. Postoperative delirium (POD) and postoperative cognitive decline (POCD) are common surgical complications. In the UK, the Best Practice Tariff incentivizes the screening of delirium in patients with hip fracture. Further, a National Hip Fracture Database (NHFD) performance indicator is the reduction in the incidence of POD. To aid in its recognition, we sought to determine factors associated with POD and POCD in patients with hip fractures. Methods. We interrogated the NHFD data on patients presenting with hip fractures to our institution from 2016 to 2018. POD was determined using the 4AT score, as recommended by the NHFD and UK Department of Health. POCD was defined as a decline in Abbreviated Mental Test Score (AMTS) of two or greater. Using logistic regression, we adjusted for covariates to identify factors associated with POD and POCD. Results. Of the 1,224 patients presenting in the study period, 1,023 had complete datasets for final analysis. POD was observed in 242 patients (25%). On multivariate analysis only preoperative AMTS and American Society of Anesthesiologists grade (ASA) were independent predictors of POD. Every point increase in AMTS was associated with a fall in the odds of POD by a factor of 0.60 (95% confidence interval (CI) 0.56 to 0.63, p < 0.001). Every grade increase in ASA led to a 1.7-fold increase in the odds of POD (95% CI 1.13 to 2.50, p = 0.009). A preoperative AMTS of less than 8 was strongly predictive of POD with area under the receiver operating characteristic of 0.86 (95% CI 0.84 to 0.89). Only ASA was predictive of POCD—every grade increase in ASA led to a 2.6-fold increase in the odds of POCD (95% CI 1.7 to 4.0, p < 0.001). Conclusion. POD and POCD are common in the hip fracture patients. Preoperative AMTS and ASA are strong predictors of POD, and ASA predictive of POCD. This may aid in the earlier identification of those most at risk and suited for the patient consent and decision-making process. Cite this article: Bone Joint J 2020;102-B(12):1675–1681

Unicompartmental knee arthroplasty (UKA) is associated with a higher risk of revision compared with total knee arthroplasty (TKA). The outcomes of knee arthroplasty are typically presented as implant survival or incidence of revision after a set number of years, which can be difficult for patients and clinicians to conceptualise. We aimed to calculate the ‘lifetime risk’ of revision for UKA as a more relatable estimate of risk projection over a patient's remaining lifetime, and make comparisons to TKA. All primary UKAS performed from 1999 to 2019 (n=13,481) captured by the New Zealand Joint Registry (NZJR) were included. The lifetime risk of revision was calculated and stratified by age, gender and American Society of Anesthesiologists (ASA) status. The lifetime risk of revision for UKA was highest in the youngest patients (46-50 years; 40.4%) and lowest in the oldest patients (86-90 years; 3.7%). Lifetime risk of revision was higher for females (range 4.3%-43.4% cf. males 2.9%-37.4%) and patients with higher ASA status (ASA 3-4 range 8.8%-41.2% cf. ASA 1 1.8%-29.8%), regardless of age. The lifetime risk of UKA was two-fold higher than TKA (ranging from 3.7%-40.4% UKA, 1.6%-22.4% TKA) across all age groups. Increased risk of revision in the younger patients was associated with aseptic loosening in both males and females, and pain in females. Periprosthetic joint infections (PJI) accounted for 4% of all UKA revisions, in contrast to 27% for TKA; risk of PJI was higher for males than females for both procedures. The lifetime risk of revision is a more meaningful measure of arthroplasty outcomes and can aid with patient counselling prior to UKA. Findings from this study show the increased lifetime risk of UKA revision for younger patients, females and those with higher ASA status