Aging of Population – Baby Boomers, Millennials, Generation X. Burden of TJR in USA – Estimated ∼ 4 million US adults currently live with TKR (4.2% of the population aged 50 or older) – Females (4.8%); Males (3.4%). Prevalence increased with increasing age. Estimated lifetime risk of primary TKR – 7.0% for males, 9.5% for females. Changes in Resident Education – Resident Work Hour Restrictions. Changes in Fellowship Education – Presumed shortage of fellowship trained arthroplasty surgeons, BWH Data. Changes in Healthcare Paradigm – Hospital – Margin/Mission, Efficiency, Contribution Margin, Ambulatory Centers. Academic/Community Practice – Revenue Driven, Diminished Education/Research Incentive. Arthroplasty Education – Time Restraints, Surgical Volume, Exposure to Options – CR/CS TKR, Revision TKR/THR, Femoral Cementing in THR. “Mind's EYE”. CME Training/Evidence-Based Medicine. Learn Basic Principles of Arthroplasty. “Be Neither the First nor Last to Embrace a New Technology”. “Always Act in the Best Interests of Your Patient”

Aims. Our primary aim was to establish the proportion of female orthopaedic consultants who perform arthroplasty via cases submitted to the National Joint Registry (NJR), which covers England, Wales, Northern Ireland, the Isle of Man, and Guernsey. Secondary aims included comparing time since specialist registration, private practice participation, and number of hospitals worked in between male and female surgeons. Methods. Publicly available data from the NJR was extracted on the types of arthroplasty performed by each surgeon, and the number of procedures of each type undertaken. Each surgeon was cross-referenced with the General Medical Council (GMC) website, using GMC number to extract surgeon demographic data. These included sex, region of practice, and dates of full and specialist registration. Results. Of 2,895 surgeons contributing to the NJR in 2023, 102 (4%) were female. The highest proportions of female surgeons were among those who performed elbow (n = 25; 5%), shoulder (n = 24; 4%), and ankle (n = 8; 4%) arthroplasty. Hip (n = 66; 3%) and knee arthroplasty (n = 39; 2%) had the lowest female representation. Female surgeons had been practising for a median of 10.4 years since specialist registration compared to 13.7 years for males (p < 0.001). Northern Ireland was the region with the highest proportion of female arthroplasty surgeons (8%). A greater proportion of male surgeons worked in private practice (63% vs 24%; p < 0.001) and in multiple hospitals (74% vs 40%; p < 0.001). Conclusion. Only 4% of surgeons currently contributing cases to the NJR are female, with the highest proportion performing elbow arthroplasty (5%). Female orthopaedic surgeons in the NJR are earlier in their careers than male surgeons, and are less involved in private practice. There is a wide geographical variation in the proportion of female arthroplasty surgeons. Cite this article: Bone Jt Open 2024;5(8):637–643

There is growing interest in the peri-operative management of patients with indications for hip and knee arthroplasty in the setting of modifiable risk factors such as morbid obesity, type 2 diabetes mellitus, and smoking. A recent survey of the American Association of Hip and Knee Surgeons (AAHKS) found that 95% of respondents address modifiable risk factors prior to surgery. The aim of this study was to poll Australian arthroplasty surgeons regarding their approach to patients with modifiable risk factors. The survey tool used in the AAHKS study was adapted for use in the Australian context and distributed to the membership of the Arthroplasty Society of Australia via Survey Monkey. Seventy-seven survey responses were received, representing a response rate of 64%. The majority of respondents were experienced, high volume arthroplasty surgeons. Overall, 91% of respondents restricted access to arthroplasty for patients with modifiable risk factors. Seventy-two percent of surgeons restricted access for excessive body mass index, 85% for poor diabetic control, and 46% for smoking. Most respondents made decisions based on personal experience or literature review rather than hospital or departmental pressures. Despite differences in healthcare systems, our findings were similar to those of the AAHKS survey, although their responses were more restrictive in all domains. Differences were noted in responses concerning financial considerations for potentially underprivileged populations. The survey is currently being administered by arthroplasty societies in six other countries, allowing comparison of orthopaedic practice across different healthcare systems around the world. In conclusion, over 90% of Australian arthroplasty surgeons who responded to the survey address modifiable risk factors prior to surgery

Abstract. Aim. To study and compare the rise of Inflammatory markers post TKR operated by Medial parapatellar approach with tourniquet (MP) and by Subvastus approach used without tourniquet. (SV). Materials and Methods. 100 patients were operated for a TKR by two experienced Arthroplasty surgeons utilising either the MP approach or the SV approach. (50 knees each). The groups were well matched as regards age, degree of deformity, obesity, pre-op knee scores and co-morbidities. The patients were managed peri-operatively in an identical manner .5 inflammatory markers viz: IL-6, AST, LDH, CRP and ESR were measured pre-operatively and at 12, 24,48 and 72 hours postoperatively. Additionally, the patients' VAS score at these intervals and Morbidity Index was determined. Results. All the 5 inflammatory markers increased post surgery in both groups. However, the rise of 4 out of the 5 inflammatory markers i(IL-6, AST, CRP, ESR) in the MP group was statistically significantly higher than in the SV group. The LDH values were similar in the two groups. The VAS scores were better in the SV group and the Morbidity Index showed a higher degree of morbidity in the MP group. Discussion. Surgical technique and approach can influence the rise of Inflammatory markers post TKR. Conclusion. The Subvastus tourniquetless approach reliably produces a lesser degree of rise in inflammatory markers post TKR than the medial parapatellar approach used with tourniquet. The subvastus approach should be utilised more to improve the immediate post-operative results following a TKR

Increased femoral head size reduces the rate of dislocation after total hip arthroplasty (THA). With the introduction of highly crosslinked polyethylene (HXLPE) liners in THA there has been a trend towards using larger size femoral heads in relatively smaller cup sizes, theoretically increasing the risk of liner fracture, wear, or aseptic loosening. Short to medium follow-up studies have not demonstrated a negative effect of using thinner HXLPE liners. However, there is concern that these thinner liners may prematurely fail in the long-term, especially in those with thinner liners. The aim of this study was to evaluate the long-term survival and revision rates of HXLPE liners in primary THA, as well as the effect of liner thickness on these outcomes. We hypothesized that there would be no significant differences between the different liner thicknesses. We performed a retrospective database analysis from a single center of all primary total hip replacements using HXLPE liners from 2010 and earlier, including all femoral head sizes. All procedures were performed by fellowship trained arthroplasty surgeons. Patient characteristics, implant details including liner thickness, death, and revisions (all causes) were recorded. Patients were grouped for analysis for each millimeter of PE thickness (e.g. 4.0-4.9mm, 5.0-5.9mm). Kaplan-Meier survival estimates were estimated with all-cause and aseptic revisions as the endpoints. A total of 2354 patients (2584 hips) were included (mean age 64.3 years, min-max 19-96). Mean BMI was 29.0 and 47.6% was female. Mean follow-up was 13.2 years (range 11.0-18.8). Liner thickness varied from 4.9 to 12.7 mm. Seven patients had a liner thickness <5.0mm and 859 had a liner thickness of <6.0mm. Head sizes were 28mm (n=85, 3.3%), 32mm (n=1214, 47.0%), 36mm (n=1176, 45.5%), and 40mm (n=109, 4.2%), and 98.4% were metal heads. There were 101 revisions, and in 78 of these cases the liner was revised. Reason for revision was instability/dislocation (n=34), pseudotumor/aseptic lymphocyte-dominant vasculitis associated lesion (n=18), fracture (n=17), early loosening (n=11), infection (n=7), aseptic loosening (n=4), and other (n=10). When grouped by liner thickness, there were no significant differences between the groups when looking at all-cause revision (p=0.112) or aseptic revision (p=0.116). In our cohort, there were no significant differences in all-cause or aseptic revisions between any of the liner thickness groups at long-term follow-up. Our results indicate that using thinner HXPE liners to maximize femoral head size in THA does not lead to increased complications or liner failures at medium to long term follow-up. As such, orthopedic surgeons can consider the use of larger heads at the cost of liner thickness a safe practice to reduce the risk of dislocation after THA when using HXLPE liners

Tourniquet use in total knee arthroplasty (TKA) remains a subject of considerable debate. A recent study questioned the need for tourniquets based on associated risks. However, the study omitted analysis of crucial tourniquet-related parameters which have been demonstrated in numerous studies to be associated with safe tourniquet use and reduction of adverse events. The current utilization and preferences of tourniquet use in Canada remain unknown. Our primary aim was to determine the current practices, patterns of use, and opinions of tourniquet use in TKA among members of the Canadian Arthroplasty Society (CAS). Additionally, we sought to determine the need for updated best practice guidelines to inform optimal tourniquet use and to identify areas requiring further research. A self-administered survey was emailed to members of the CAS in October 2021(six-week period). The response rate was 57% (91/161). Skip logic branching was used to administer a maximum of 59 questions related to tourniquet use, beliefs, and practices. All respondents were staff surgeons and 88% were arthroplasty fellowship trained. Sixty-five percent have been in practice for ≥11 years and only 16% for 50 TKA/year, 59% have an academic practice, and >67% prefer cemented TKA. Sixty-six percent currently use tourniquets, 25% no longer do but previously did, and 9% never used tourniquets. For those not using tourniquets, the most common reasons are potential harm/risks and publications/conferences. Among current users, 48% use in all cases and an additional 37% use in 76-99% of cases. The top reason for use was improved visualization/bloodless field (88%), followed by performing a cemented TKA, used in training, and faster operative times. The main patient factor influencing selective tourniquet use was peripheral vascular disease and main surgical factors were operative duration and cementless TKA. The most frequent adverse events reported were bruising/pinching under the tourniquet and short-term pain, which majority believed were related to improper tourniquet use (prolonged time, high-pressures, poor cuff fit), yet only 8% use contoured tourniquets and 32% don't use limb protection. Despite substantial evidence in literature that tourniquet safety and probability of harm are affected by tourniquet time and pressure, only 83% and 72% of respondents believe reducing tourniquet time and pressure respectively reduce the probability of harm. In addition, no surgeon utilizes personalized limb occlusion pressure which has been demonstrated to substantially reduce tourniquet pressure while being safe and effective. Furthermore, 62% always use fixed pressure and 37% will modify the pressure based on patient parameters, most often systolic blood pressure and limb size. Almost all (88%) were interested in new evidence-based guidelines regarding these parameters. Tourniquet use in TKA remains prevalent among arthroplasty surgeons in the CAS; however tremendous practice variability regarding several key parameters required for optimal use exists. Current best practices of tourniquet use regarding personalized pressures, time, and type are not being utilized across Canada. There is considerable interest and need for further research and updated guidelines regarding key parameters of safe tourniquet usage to optimize tourniquet use in TKA

Aim. Whether laminar airflow (LAF) in the operating room (OR) is effective for decreasing periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant yet controversial issue. This study investigated the association between operating room ventilation systems and the risk of PJI in TJA patients. Method. We performed a retrospective observational study on consecutive patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) from January 2013-September 2017 in two surgical facilities within a single institution, with a minimum 1-year follow-up. All procedures were performed by five board-certified arthroplasty surgeons. The operating rooms at the facilities were equipped with LAF and turbulent ventilation systems, respectively. Patient characteristics were extracted from clinical records. PJI was defined according to Musculoskeletal Infection Society criteria within 1-year of the index arthroplasty. A multivariate logistic regression model was performed to explore the association between LAF and risk of 1-year PJI, and then a sensitivity analysis using propensity score matching (PSM) was performed to further validate the findings. Results. A total of 6,972 patients (2,797 TKA, 4,175 THA) were included. The incidence of PJI within 1 year for patients from the facility without laminar flow was similar at 0·4% to that of patients from the facility with laminar flow at 0·5%. In the multivariate logistic regression analysis, after all confounding factors were taken into account, the use of LAF was not significantly associated with reduction of the risk of PJI. After propensity score matching, there was no significant difference in the incidence of PJI within 1 year for patients between the two sites. Conclusions. The use of LAF in the operating room was not associated with a reduced incidence of PJI following primary TJA. With an appropriate perioperative protocol for infection prevention, LAF does not seem to play a protective role in PJI prevention

Introduction. Legg-Calvé-Perthes disease (LCPD) often results in femoral head deformity and leg length discrepancy (LLD). Objective of this study was to analyse femoral morphology in LCPD patients at skeletal maturity to assess where the LLD originates, and evaluate the effect of contralateral epiphysiodesis for length equalisation on proximal and subtrochanteric femoral lengths. Materials and Methods. All patients treated for LCPD in our institution between January 2013 and June 2020 were retrospectively reviewed. Patients with unilateral LCPD, LLD of ≥5mm and long leg standing radiographs at skeletal maturity were included. Total leg length, femoral and tibial length, articulotrochanteric distance (ATD) and subtrochanteric femoral length were compared between LCPD side and unaffected side. Furthermore, we compared leg length measurements between patients who did and who did not have a contralateral epiphysiodesis. Results. 79 patients were included, 21/79 underwent contralateral epiphysiodesis for leg length correction. In the complete cohort the average LLD was 1.8cm (95% CI 1.5 – 2.0), average ATD difference was 1.8cm (95% CI −2.1 – −1.9) and average subtrochanteric difference was −0.2cm (95% CI −0.4 – 0.1). In the epiphysiodesis group the average LLD before epiphysiodesis was 2.7 (1.3 – 3.4) cm and 1.3 (−0.5 – 3.8) cm at skeletal maturity. In the non-epiphysiodesis group the average LLD was 2.0 (0.5 – 5.1), p=0.016. The subtrochanteric region on the LCPD side was significantly longer at skeletal maturity in the epiphysiodesis group compared to the non-epiphysiodesis group: −1.0 (−2.4 – 0.6) versus 0.1 (−1.0 – 2.1), p<0.001. Conclusions. This study concludes that LLD after LCPD originates from the proximal segment only. In patients who had had a contralateral epiphysiodesis, the subtrochanteric femoral region was significantly longer on the LCPD side. These anatomical changes need to be considered by paediatric surgeons when advising leg length equalisation procedures, and by arthroplasty surgeons when LCPD patients present for hip arthroplasty

Background. Total hip arthroplasty (THA) has been and continues to be the gold standard for treatment of end-stage osteoarthritis. With each year, implant characteristics are evolving to increase patient-reported outcomes and decrease complications. Purpose: to report minimum 2-year outcomes and complications in patients who underwent robotic-arm assisted THA using Corin versus Stryker-type implants. Methods. Data were prospectively collected on patients who underwent THA with Corin-type implants (both cup and stem) and THA using Stryker implants between June 2011 and July 2016. A 1:1 propensity match was performed using the following 5 covariates: age, body mass index, gender, Charlson score and smoking status. Surgical outcomes were assessed at minimum 2-year follow-up using the Forgotten Joint Score (FJS), Harris Hip Score (HHS), Veterans RAND 12-item physical and mental health survey, Short Form 12 physical and mental health survey, Visual Analog Score (VAS), and patient satisfaction. The exclusion criteria were previous hip condition/surgery, workers compensation, or were unwilling. Results. Of the eligible 774 cases, 645 patients (83.3%) had minimum 2-year follow-up and met inclusion and exclusion criteria. Of the 645 patients, 323 had Corin implants, and 155 had Stryker implants. The 1:1 propensity match successfully yielded 290 patients (145 per implant group) which had a minimum 2-year follow-up at a mean 38.3 months (range, 24.1–65.3 months). Average age was 59.9 (range, 34.92–79.89 Stryker group, 30.65–75.92 Corin group) for each group and average BMI were 30.0 (range, 19.05–49.33) kg/m. 2. for the Stryker group and 29.77 (range, 20.15–55.37) kg/m. 2. for the Corin group. FJS (P=0.0388) and patient satisfaction (P=0.0019) were significantly higher in the Stryker implant group than the Corin implant group. There were nine cases of postoperative thigh numbness or paresthesias, three cases of wound infection, and one case of nonunion in the Corin-implant group. There were four cases of postoperative thigh numbness or parasthesias and six cases of wound infection in the Stryker-implant group. Conclusion. At minimum 2-year follow-up, patients who had undergone THA with Stryker-type implants had significantly higher FJS and satisfaction and a trend toward decreased complications than patients with Corin-type implants. These results can help guide decision making for surgical instrumentation by arthroplasty surgeons

The anterior approach is now an accepted approach for total hip arthroplasty. First described over a century ago, its popularity has grown significantly in the last decade with the advent of a reproducible technique on an orthopaedic table. Potential advantages include quicker recovery times, less post-operative pain, improved hip biomechanics, and more accurate cup position. While both femoral exposure and learning curve are often cited as potential drawbacks, a large percentage of US surgeons now utilise this teachable approach. The adoption of this approach has facilitated the development of new tools to assist the arthroplasty surgeon in a more efficient and efficacious manner. The anterior approach is performed with the patient in a supine position on an orthopaedic table. The supine position provides improved visualization of the acetabulum, appreciation of pelvic position as well as the advantage of intra-operative fluoroscopy. While many technologies including navigation and first generation robotics exist to assist the surgeon with virtual information; only fluoroscopy provides the surgeon with real time actual information. The interpretation of fluoroscopic images carries a learning curve and potential for error. New technology now exists to assist the surgeon to better interpret fluoroscopic images including anteversion and abduction of cup, leg length and offset. Since the first hip surgery was performed by Sir John Charnley, hip surgeons have utilised specialised tools including reamers, drills, saws, and mallets during surgery to assist with cup insertion, femoral preparation, stem insertion, liner insertion and head impaction. Many tools in the operating room including drills, reamers, and saws have moved from hand powered operation to pneumatic and now battery powered operation to assist with efficiency, efficacy, and reduced surgeon fatigue. A new, battery powered impaction device provides a consistent and constant energy that does not rely on the surgeon's mallet speed, throw distance, or impact contact. This may represent the next generation of surgical tools available to the arthroplasty surgeon that has the potential to make the mallet obsolete

In the USA, 34.9% of adults are currently obese (BMI > 30). Growth in total knee arthroplasty (TKA) is outpacing growth in total hip arthroplasty (THA) largely due to a differential utilization of TKA in overweight patients in the USA. In a recent study, 54.5% of patients reporting to arthroplasty clinics in the USA were obese. From 2006–2010, 61.2% of primary unilateral TKA patients in the USA ACS-NSQIP database were obese. Arthroplasty surgeons are directly affected by the obesity epidemic and need to understand how to safely offer a range of peri-operative care for these patients in order to insure good clinical outcomes. Pre-operative care for the obese patient involves nutritional counseling, weight loss methods, consideration for bariatric surgery, physical therapy, metabolic workup, and diagnosis and management of frequent comorbid conditions (OSA, DM2, HTN, HLD). Obese patients must also be counseled on their increased risk of complications following TKA. In the operating room, several steps can be taken to insure success when performing TKA on obese patients. We recommend performing TKA without the use of a tourniquet in order to prevent fat necrosis and increased pain. The incision is made in 90 degrees of knee flexion, atypically midline proximally and curved distally to the midpoint between the tubercle and the medial edge of the tibia. Care is used to minimise the creation of dead space, and the approach to the knee is an extensile medial parapatellar incision. Closure is in multiple layers. The use of negative pressure dressing following surgery can minimise the early wound drainage that is frequently seen after TKA in obese patients. Post-operative care of the obese patient following TKA involves several unique considerations. Chronic pain and obesity are frequent comorbid conditions and post-operative pain control regimens need to be tailored. Although the physical therapy regimen does not differ in obese patients, obese patients are more likely to be discharged to a rehabilitation facility. Obese patients have a higher rate of all complications compared to healthy weight. All infection and deep infection increased in obese patients in large meta-analysis. Patients with BMI > 35 are 6.7 times more likely to develop infection after TKA. Patients with BMI > 40 have a 3.35 times higher rate of revision for deep infection than those with BMI < 35. The odds ratio for major complications increases dramatically beyond BMI > 45. Although there are a few studies that have demonstrated worse clinical outcome in obese patients following TKA, most studies show no difference in clinical outcomes at short- or long-term follow-up. The arthroplasty surgeon must optimise the obese patient prior to surgery, use intra-operative techniques to maximise success, and anticipate potential problems in the post-operative course in order to achieve success with TKA in obese patients

Background. Highly porous acetabular components are widely used in revision hip surgery. The purpose of this study is to compare the mid-term survivorship, clinical and radiological outcomes of a hemispherical cup (Stryker Tritanium Revision component) and a peripherally expanded cup (Zimmer TM modular component) in revision hip surgery. Methods. Between 2010 and 2017, 30 patients underwent revision hip replacement using a hemispherical cup and 54 patients using a peripherally expanded cup. The surgery was carried out by two arthroplasty surgeons, both fellowship-trained in revision hip surgery. Kaplan-Meier analysis was used to determine the survivorship of the components. Clinical outcomes were measured using the Oxford Hip Score. Radiographs were analysed for the presence of radiolucent lines in the DeLee and Charnley zones. Results. Follow up of both components ranged from 2 – 8 years. All the hemispherical cups were reinforced with screws whilst 86% of the peripherally expanded cups required screws. Four (13%) of the hemispherical cups required re-revision surgery for aseptic loosening. One (2%) of the peripherally expanded cups was revised for dislocation, but none for aseptic loosening. None of the peripherally expanded cups exhibited significant radiolucency as compared to 8 (27%) hemispherical cups. The mean Oxford Hip Score of the hemispherical and peripherally expanded cups was 38 and 40 respectively. Using revision for any cause as the end, survivorship of the hemispherical cups at 7.6 years was 80.66% while the peripherally expanded cups at 8.2 years was 98.15%. Conclusions. In our case-series, a peripherally expanded cup has shown a better mid-term radiological and clinical result, with a lower rate of re-revision surgery, when compared to a hemispherical cup

Clinical cases will be presented to a panel of experienced arthroplasty surgeons to illustrate how principles tempered by experience, are applied to challenging problems. (request pertinent additional material from . kellyvince@mac.com. )

Introduction. Total hip arthroplasty (THA) is a highly successful procedure achieving excellent clinical outcomes beyond 10 years post-surgery. With exception of periprosthetic infection, dislocation is the most common cause of failure in THA. A novel reverse total hip (RTH) replacement has been developed to address dislocation through reversal of the typical THA articulation in which a femoral cup and acetabular ball interlock at the extremes of motion to enhance mechanical stability in all planes. The purpose of this study was to assess the safety and efficacy of this novel RTH in a series of 22 patients and to monitor implant fixation using radiostereometric analysis (RSA). Methods. Twenty two patients with end-stage osteoarthritis of the hip were enrolled between 2017 and 2019 at a single center. All surgeries were performed by a group of four high-volume fellowship-trained arthroplasty surgeons. All patients received at least 1 acetabular cup screw and RSA markers inserted into the acetabulum and proximal femur. Follow-up time points were 6 weeks, 6, 12 and 24 months and included patient reported outcome measures (HOOS, Oxford-12, Harris Hip Score, SF-36 and Satisfaction) as well as RSA assessment. Results. The patient cohort consisted of 11 females and 11 males with mean age of 70.8 years and body mass index 31.3 kg/m. 2. At the time of writing, 21, 15 and 3 patients had completed their 6-month, 1- and 2-year clinical follow-ups, respectively. There was a significant improvement in function and pain with the RTH between pre-operative and six and twelve month follow up as collected by the HOOS, Oxfrod-12, HHS, WOMAC, EQ-5D and SF-36 PCS with p<0.001 for all. The sole exception was the SF-36 MCS which had a non-statistical improvement. Eighteen of 20 patients were satisfied or very satisfied with the outcome of surgery. Average vertical migration of the acetabular cup at 6 and 12 months was 0.082 mm and 0.110 mm, respectively. Average distal migration of the femoral stem at 6 and 12 months was 0.015 mm and 0.035 mm, respectively. Conclusions. Early results indicate acceptable safety and efficacy of this novel RTH for treating osteoarthritis of the hip. The femoral and acetabular components both appear well fixed at near-term follow-up, as assessed with RSA. Further follow-up will determine if these results are maintained at 24 months post-surgery. Additional patient enrollment will assess acetabular cup fixation without the use of screws. For any figures or tables, please contact authors directly

Aim. The incidence of early periprosthetic joint infection (PJI) after total hip arthroplasty (THA) and total knee arthroplasty (TKA) is between 1 and 2 percent. In our department approximately 700 primary THAs and TKAs are performed annually. In 2015 and 2016 the incidence of early PJIs was nearly 3%. The aim of this study was to see if it was possible to reduce the incidence of infection by employing a bundle of measures by involving staff from all aspects of patient flow and addressing preventing measures in every step of the patients´ course throughout the hospital. Method. The Arthroplasty surgeon team reviewed the Proceedings of the International Consensus Meeting on Periprosthetic Joint Infection of 2013. Issues where literature had shown a significant effect on prevention of PJI was identified and written in an action plan. An interdisciplinary team with staff from all aspects of patient flow was established. In January 2017 the action plan was presented to the interdisciplinary team. The team discussed in what way the different issues could be solved, and issues that could be addressed without extra costs were implemented immediately. The issues addressed in the meeting were: preoperative risk factors, preoperative skin preparation, perioperative antibiotics, reducing particle amount and reducing traffic in the surgical theatre. Results. Early PJIs (symptoms within 30 days of index surgery) has been registered in our local quality register since 2011. Every infection is assured in order to apply to international criteria. There were 31 early PJIs among the 1100 primary THAs and TKAs performed before the intervention and 13 early PJIs among the 1100 after. The incidence the last two years before the intervention was 2.7% and the two years after intervention incidence was 1.2% (p=0.009). Conclusions. In this study we have shown that it is possible to reduce the incidence of early periprosthetic infections after primary THA and TKA in a university hospital. The patients referred to our department are of all categories, from healthy to great comorbidity. By focusing on optimizing the patient, preoperative antibiotics and traffic and behavior in the surgical theatre, we were able to reduce the infection incidence significantly. It is important to address the whole patient course, and introduce bundle of measures, in addition to involving staff from all aspects of the patient flow

Purpose. South African arthroplasty surgeons commonly make use of new bearing surface technology. This new technology only has short term, industry funded clinical trials or simulator studies available to prove its performance and motivate its use. These products are being used despite the availability of conventional components with proven long term in vivo efficacy. In the light of the recent Du Puy ASR recall, which also showed initial good clinical results, we reviewed the available data on some of the new available bearing surface technology. Methods. We performed a literature search to identify the best available clinical data regarding duration of follow up and number of patients for a selection of new bearing surfaces and compared it to well known long term clinical follow up studies and joint registry data of conventional products. Results. New bearing surface technologies have no long term clinical supportive data. Short and medium term results are available, however these are limited and mainly industry funded. Simulator data constituts the bulk of research used as motivation for the introduction of new technologies. Conclusion. The currently available data on new bearing surface technology is not adequate to provide the arthroplasty surgeon with a confident opinion on long term safety and efficacy. Surgeons should be careful when recommending new products to their patients, who are usually well informed of new technology but often without the necessary insight. NO DISCLOSURES

Background. Cementless Total Knee Arthroplasty has been developed to reduce the incidence of failure secondary to aseptic loosening, osteolysis and stress-induced osteopenia, especially in younger and more active patients. However, failures are still more common compared to cemented components, especially those involving the tibia. It is hypothesized that this is caused by incomplete contact between the tibial tray and the underlying bony surface due to: (i) inadequate flatness of the tibial osteotomy, or (ii) failure of implantation to spread the area of contact over the exposed cancellous surface. In the present study we compare the contact area developed during implantation of a cementless tray as a function of the initial flatness of the tibial osteotomy. Method. Eight joint replacement surgeons prepared 14 cadaveric knees for cementless TKR using a standard instrumentation set (ZimmerBiomet Inc). The tibial osteotomy was created using an oscillating bone saw and a 1.27mm blade (Stryker Inc) directed by a slotted cutting guide mounted on an extramedullary rod and fixed to the tibia with pins and screws. The topography of the exposed cancellous surface was captured with a commercial laser scanner (Faro Inc, Halifax, approx. 33,000 surface points). 3D computer models of each tibial surface were generated in a CAD environment (Rapidform, Inuus). After scanning, a cementless tibial tray was implanted on the prepared tibial surface using a manual impactor. The tray-tibia constructs were dissected free of soft tissue, embedded in mounting resin, and sectioned with a diamond wafering saw. Points of bone-tray contact and interface separation were identified by stereomicroscopy and incorporated in the 3D computer models. Maps were generated depicting contacting and non-contacting areas Each model was subdivided into 7 zones for characterizing the distribution of interface contact in terms of anatomic location. Results. The flatness for the tibial osteotomies averaged 1.1±0.35 mm (range: 0.56–1.81mm). After impaction, 79.8±0.3% of the tibial surface had plastically deformed to establish a contacting interface with the implant. 15.1% of the bony surface was within 0.2mm of the tray and 17.6% was within 0.3mm. Gaps large enough to impede ingrowth only occupied 2.6% of the exposed tibial These non-contacting areas were typically located centrally at the ACL, PCL and canal zones. There was an inverse linear relationship between the initial flatness of the tibial osteotomy and the percentage of tray-bone contact. Conclusions. The amount of direct contact between the bone and implant is critical for the development of stability in cementless fixation. We found a relationship between ultimate bony contact and initial flatness. However, we also found that during impaction of the implant, bony contact increased through deformation of the most prominent peaks of the cancellous surface. Interface gaps were consistently observed in central areas of the tibia surface located above the medullary canal which may be reduced through selection of trays with distal keels. For any figures or tables, please contact authors directly

Introduction. The purpose of this study is to compare total and rate of caloric energy expenditure between conventional and robotic-arm assisted total knee arthroplasty (TKA) between a high volume “veteran” surgeon (HV) and a lower volume, less experienced surgeon (LV). Methods. Two specialized arthroplasty surgeons wore a biometric-enabled shirt and energy expenditure outcomes were measured (total caloric expenditure, kilocalories per minute, heart rate variability, and surgical duration) during 35 conventional (CTKA) and 29 robotic primary total knee arthroplasty (RTKA) procedures. Results. Overall, the rate of caloric expenditure was similar between RTKA (5.60 ±2.50 kcal/min) and CTKA (4.79cal/min ±1.79, p=0.25). With 6.15 minute longer operative times, the total energy expenditure (TEE) for RTKA (239.31±96.79 kcal) was higher thanCTKA(181.54 ±80.90 kcal, p<0.001). The HV surgeon's TEE (p<0.001) and rate of energy expenditure (REE) (p<0.001) were significantly higher in RTKA (261.53cal; 6.499cal/min) versus CTKA (71.00cal; 3.759cal/min). However, the LV surgeon's TEE and REE for RTKA (207.83cal; 4.32cal/min) and CTKA (195.81cal; 4.92cal/min) were not significantly different (p>0.05). Both surgeons (HV; LV) had significantly longer surgical durations (p<0.001) in RTKA (40.41 ±4.94min; 48.91 ±8.45min) compared to CTKA surgeries (18.75±4.27min; 40.4 ±8.34min), respectively. Conclusion. While REE did not varybetween CTKA and RTKA for the LV surgeon, it did vary significantly for the HV surgeon. Additionally, RTKA took longer and increased TEE, but one less operating room assistant was needed. Surgeons with less experience in TKA may be less likely to notice a difference in energy expenditure when utilizing robotic-arm assisted technology. It is possible that more experience with using the robotic arm could create efficiencies over time that may also reduce TEE

Background. The Bundled Payments for Care Improvement (BPCI) was developed by the US Center for Medicare and Medicaid (CMS) to evaluate a payment and service delivery model to reduce cost but preserve quality. 90 day postoperative expenditures are reconciled against a target price, allowing for a monetary bonus to the provider if savings were achieved. The surgeon is placed in a position to optimize the patients preoperatively to minimize expensive postoperative cardiovascular readmissions in a high risk population. Traditionally, surgeons request that primary care providers medically clear the patient for surgery with or without additional cardiology consultation, without dictating specific testing. Typical screening includes an EKG, occasionally an echocardiogram and nuclear stress test, and rarely a cardiac catheterization. Our participation in the BPCI program for total hip and knee replacement surgeries since 1/1/15 has demonstrated a significant number of patients having readmissions for cardiac events. Objective. To determine the medical effectiveness and cost savings of instituting a new innovative cardiac screening program (Preventive Cardio-Orthopaedics) for total hip and knee replacement patients in the BPCI program and to compare result to those managed in the more traditional fashion. Methods. The new screening program was instituted on 11/1/17 directed by an advanced cardiac imaging cardiologist (EH). Testing included an electrocardiogram, echocardiogram, carotid and abdominal ultrasound, and coronary computed tomography angiography (CCTA). If needed, a 3 day cardiac rhythm monitor was also performed. Four of the ten physicians in our group performing hip and knee replacement surgeries participated. Charts of readmitted patients were reviewed to determine past medical history, method of cardiac clearance, length and cost of readmission. Results. 1,361 patients had total hip or knee replacement in the BPCI program between 1/1/15 and 1/28/18 and all had complete 90 day postoperative readmission data supplied by the CMS, with 25 of these patients evaluated through the Preventive Cardio- Orthopaedics program. 12 (0.90%) screened via the traditional cardiac program had a cardiac event readmission. The average readmission hospital stay was 3.67 days at a total cost of $69,378. 7 of 12 had a preoperative clearance by a cardiologist. In 9 of the 12 patients, the only preoperative cardiac screening tool performed was an electrocardiogram. None of these 25 patients evaluated through the new program has been readmitted. 84 more patients have been evaluated in this program since 1/28/18, but 90 day readmission data is still incomplete. Preliminary data suggests that the highest risk in these patients is not severe coronary artery disease, but atrial fibrillation, hypertension with left ventricular hypertrophy, and cardiac plaques with ulceration. Conclusions. Risk sharing programs have forced joint replacement surgeons to take a more active role in optimizing their patients medically; otherwise they will be penalized with a decreased reimbursement. Traditionally, we have abdicated this responsibility to primary care and cardiology physicians but have noted a high readmission risk with a cardiac event. In response, we have begun using a unique cardiac screening model. Our preliminary experience predicts fewer cardiac readmissions thereby improving care, and at a lower cost

Debridement Antibiotics Implant Retention (DAIR) is a recognised procedure in the management of acute prosthetic joint infection (PJI). We present an experience of DAIR following hip and knee replacements in a District General Hospital. A retrospective review of 14 patients who underwent DAIR procedures between August 2012 and December 1015 were collated. The cohort included primary, complex primary and revision hip and knee replacements. All patients received multidisciplinary care with surgery performed by one of two arthroplasty surgeons. 9 males and 5 females with age 62 − 78 years (Mean 70.7) and BMI 22–44.2 (Mean 33.8) with various co-morbidities underwent DAIR. Surgical criteria required DAIR to be performed within 3 weeks of the onset of symptoms of infection. The time from index surgery however ranged from 15 days to 58 months. 12 of 14 grew positive cultures including two growing Vancomycin Resistant Enterococcus. Intravenous antibiotics were commenced after intraoperative samples and tailored OPAT. Antibiotic schedule varied from six weeks to eight months. 12 (85.7%) patients remain under follow up. Mean follow is 20 months (RANGE 6months-3years10months) with no recurrence of infection or reoperation. With appropriate patient selection, DAIR is safe and reproducible surgical option in PJI in hip and knee replacements, avoiding the implications of a one or two stage revision. Published Data in contemporary literature is predominantly from specialised centres. Our small series provides a perspective of early to mid term results of DAIR to DGH. Interestingly each procedure is categorised as a failed implant on the National Joint Register