Major Joint Arthroplasty Research Articles

Revision Arthroplasty Among Medicare Patients in the United States – Arthroplasty Surgeons are Doing More for Less

BackgroundPreviously documented trends of major joint arthroplasty demonstrate increasing volume and decreasing reimbursement for primary total knee and total hip arthroplasty procedures. As such, the purpose of this study was to evaluate trends in revision knee and hip arthroplasty volume and true Medicare reimbursements to physicians. MethodsThe publicly accessible Centers for Medicare and Medicaid files were evaluated. Data were retrieved from the Part B National Summary Data File and queried for revision knee and hip arthroplasty billed to Medicare from 2000 to 2021. The total charge submitted to Medicare, Medicare reimbursement, number of revision arthroplasty surgeries performed, and average reimbursement per surgery were collected for each year. All monetary data were adjusted for inflation to 2021 dollars. ResultsThere were 492,360 revision total knee arthroplasty surgeries and 424,163 revision hip arthroplasty procedures billed to Medicare from 2000 to 2021. Medicare was billed a total of $919,603,674.86 for revision knee and $862,979,761.57 for revision hip arthroplasty during that time. Medicare reimbursed physicians an average of $1,499.89 per knee revision and $1,603.32 per hip revision surgery. The total volume of revision knee arthroplasty increased by 9,380 (62%) and revision hip decreased by 1,743 (9%) from the year 2000 to 2021. However, there was a decrease of average reimbursement per procedure of more than 37% ($1,987.14 to 1,254) and 39% ($2,149.87 to 1,311.17), respectively. ConclusionsDespite a notable increase in the volume of revision total knee and stagnant revision hip arthroplasty, total billings to and reimbursements from Medicare for these procedures have not changed markedly per year. Importantly, this means that physicians are conducting more of these high-impact procedures yearly, while being reimbursed per procedure at a declining rate. This may indicate a need to re-assess billing and reimbursement rates for revision arthroplasty, in the context of the ever-increasing inflation rate.

Effect of body mass index on acute postoperative complications following Total Ankle Arthroplasty (TAA)

BackgroundTotal ankle arthroplasty (TAA) is an effective treatment for various ankle pathologies, but some concern remains for the high associated complication and failure rates relative to major joint arthroplasty of the hip and knee. Patient body mass index (BMI) is a modifiable and potentially important preoperative variable when evaluating postoperative complications. The purpose of this study is to evaluate the effect of BMI, age and sex on the acute postoperative complication rate after TAA. MethodsWe retrospectively reviewed adult patients who underwent TAA between 2006 and 2021 from the NSQIP database. Using overweight patients as the reference BMI group, we utilized log-binomial models to estimate risk ratios on outcomes while adjusting for sex and age to investigate whether there were significant adjusted differences in complication rates among the BMI groups. ResultsWe found that, relative to overweight patients, there were no statistically significant differences in the risk of acute complications for underweight (BMI < 18.5) (P = .118), healthy weight (18.5≤BMI < 25) (P = .544), obese (30≤BMI < 40) (P = .930), or morbidly obese (BMI < 40) (P = .602) patients who underwent TAA. There were also no statistically significant differences in the risk of acute complications based on age category (P = .482,.824) or sex (P = .440) for TAA. Additionally, there were no significant differences between the BMI groups for either major complications (P = .980) or minor complications (P = .168). ConclusionUltimately, we found that BMI, age, and sex did not lead to statistically significant differences in the risk of complications within 30 days postoperatively for TAA, even when stratified by major vs minor complications. Level of EvidenceLevel III

Effect of BMI on Acute Postoperative Complications following Total Ankle Arthroplasty (TAA)

Category: Ankle Introduction/Purpose: Total ankle arthroplasty (TAA) is an effective treatment for various ankle pathologies, but some concern remains for the relatively high associated complication and failure rates relative to major joint arthroplasty of the hip and knee. Patient body mass index (BMI) is a modifiable and potentially important preoperative variable when evaluating postoperative complications. The purpose of this study is to evaluate the effect of BMI on the acute postoperative complication rate after TAA. Methods: We performed a retrospective review to identify a large cohort of adult patients who underwent TAA between 2006 - 2020 from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Using overweight patients as the reference BMI group, we estimated log-binomial models to estimate risk ratios on outcomes, while also adjusting for sex and age, in order to investigate whether there was a significant difference in complication rate between the BMI groups. Results: We found that, relative to overweight patients, there was no statistically significant difference in the risk of acute complications for underweight (p-value=0.062), healthy weight (p-value=0.800), obese (p-value=0.993), or morbidly obese (p- value=0.781) patients who underwent TAA. There was also no statistically significant difference in the risk of acute complications based on age (p-value=0.876) or sex (p-value=0.696) for TAA. Additionally, there was no significant difference between the BMI groups when comparing how many patients had a complication out of the total number of patients in their respective BMI group for either major complications (p-value=0.9835) or minor complications (p-value=0.0578). Conclusion: We found that BMI, age, and sex did not lead to a statistically significant difference in the risk of complications, even when stratified by major vs minor complications, within 30 days postoperatively for TAA.

Large Variation in Listed Chargemaster Price for Total Joint Arthroplasty Among Top Orthopaedic Hospitals in the United States.

Chargemasters are lists of all services offered by a hospital and their associated cost. This study analyzes chargemaster data to determine price differences among different hospitals for total joint arthroplasty. In May 2020, the chargemaster data for highly rated orthopaedic hospitals were accessed, and the diagnostic-related group (DRG) codes related to primary and revision total joint arthroplasty were analyzed (DRGs 466, 467, 468, 469, and 470). The prices listed for each hospital were averaged, and descriptive statistics were calculated. Furthermore, Medicare reimbursement was collected. A subanalysis was performed to determine relationships between geographic and demographic information. The median price for a major hip or knee joint arthroplasty without complications was $68,016 (range: $39,927 to $195,264). The median price of a revision of hip or knee arthroplasty without complications was $90,966 (range: $58,967 to $247,715). The cost of living in the city in which the hospitals are located was weakly correlated with procedure pricing, whereas the median income had no notable relationship to chargemaster pricing. The published cost of DRG codes in arthroplasty is widely variable among the top 20 US orthopaedic hospitals, with little correlation to the cost of living or median income of the area.

Hospital and Surgeon Competition and Its Association with Disclosure of Payments for Major Joint Arthroplasty

Zhang, Gloria X; Peairs, Emily M BS; Zhang, Yuqi MD; Cerullo, Marcelo MD, MPH Author Information

RESTARTING ELECTIVE ORTHOPAEDIC SERVICES ACROSS SCOTLAND DURING A YEAR OF COVID-19

COVID 19 led to massive disruption of elective services across Scotland. This study was designed to assess the impact on elective service that the COVID-19 pandemic had, to what extent services have been restarted and the associated risks are in doing so.This is a retrospective observational study. The primary outcomes are the number of operations completed, 30-day mortality, 30-day complication rates and nosocomial infection with COVID-19 compared to previous years. Data was collected from 4 regions across Scotland from 27th March 2020 - 26th March 2021. This was compared to the same time period the previous year.3431 elective operations were completed in the year post-pandemic compared with 12255, demonstrating a reduction of 72%. Both groups had comparable demographics. Major joint arthroplasty saw a 72% reduction, with TKR seeing a reduction of 82%. Each of the 4 health boards were affected in a similar fashion. Nosocomial COVID-19 infection was 0.4% in the post covid group. 30 day mortality was the same at 0.1%. Total complications rose from 5.7% to 10.1% post covid.This study shows that there has been a substantial reduction in elective activity across Scotland that is disproportionate to the level of COVID-19. The risk of developing COVID-19 from elective surgery is low at 0.4%, however all complications saw a significant rise. This is likely multifactorial. This study will inform decision makers in future pandemics, that it is safe to continue elective orthopaedic surgery and of the potential impact of cessation of services.

Hematoma Following Shoulder Arthroplasty: Incidence, Management, and Outcomes.

A paucity of data regarding the implications of postoperative hematoma formation on outcomes after shoulder arthroplasty exists. Previous studies on major joint arthroplasty have associated postoperative hematoma formation with high rates of prosthetic joint infection (PJI) and reoperation. A total of 6,421 shoulder arthroplasty cases were retrospectively reviewed from an institutional database (5,941 primary cases, 480 revision) between December 2008 and July 2017. Patients who developed a postoperative hematoma were identified through direct chart review. Cases with a history of shoulder infection treated with explant and antibiotic spacer placement were excluded. Demographics, surgical characteristics, treatment course, and outcomes were collected. Hematoma occurred in 105 (1.6%; 105/6421) cases within the first three postoperative weeks and was more common following revision (3.3%; 16/480) compared to primary cases (1.5 %; 89/5941; P=0.002). Overall, postoperative shoulder hematoma was successfully managed with nonoperative treatment in 87% of cases via observation (62%, 62/105) and aspiration (25%, 26/105). A total of 14 patients (0.22%, 14/6421) underwent reoperation for hematoma. Eight patients (7.6%, 8/105) that required reoperation for hematoma were diagnosed with PJI. Postoperative hematoma is a complication of shoulder arthroplasty. While many postoperative hematomas can be managed without operative intervention, this analysis reiterates the association between hematoma formation and the development of PJI.

A Retrospective Study of Anticholinergic Use and Later Mobilization as Risk Factors for Urinary Retention After Major Lower Extremity Joint Arthroplasty

BackgroundPostoperative urinary retention (POUR) is a common surgical complication of major joint arthroplasty and is associated with increased lengths of stay and urinary tract infections. Studies have found that certain anticholinergic medications and reduced mobility are associated with POUR. This study assessed the effect of anticholinergic burden and later postoperative ambulation on POUR. MethodsIn this retrospective cohort study, we included subjects who had undergone elective primary or revision hip or knee arthroplasty (total hip arthroplasty [THA] or total knee arthroplasty [TKA]) between March 2015 and December 2017 in a single health system. Anticholinergic burden was measured using the Anticholinergic Drug Scale (ADS). We performed bivariate and multivariable logistic regression with POUR as the dependent variable. Of the 1,397 study subjects, 622 (45%) underwent THA and 775 (55%) underwent TKA. Their mean age was 65 years (range, 21 to 98), and 841 (60%) were women. POUR developed in 183 (13%) subjects. ResultsIn multivariable analyses, ADS was associated with POUR after THA (P < .05), but not TKA (P = .08), while later ambulation was not associated with POUR after either procedure (P > .3 for both). ConclusionAnticholinergic burden after THA was independently associated with POUR. Strategies to reduce anticholinergic burden may help reduce POUR after THA.

Patient Out-of-Pocket Cost Burden With Elective Orthopaedic Surgery.

Out-of-pocket (OOP) costs for medical and surgical care can result in substantial financial burden for patients and families. Relatively little is known regarding OOP costs for commercially insured patients receiving orthopaedic surgery. The aim of this study is to analyze the trends in OOP costs for common, elective orthopaedic surgeries performed in the hospital inpatient setting. This study used an employer-sponsored insurance claims database to analyze billing data of commercially insured patients who underwent elective orthopaedic surgery between 2014 and 2019. Patients who received single-level anterior cervical diskectomy and fusion (ACDF), single-level posterior lumbar fusion (PLF), total knee arthroplasty (TKA), and total hip arthroplasty (THA) were identified. OOP costs associated with the surgical episode were calculated as the sum of deductible payments, copayments, and coinsurance. Monetary data were adjusted to 2019 dollars. General linear regression, Wilcoxon-Mann-Whitney, and Kruskal-Wallis tests were used for analysis, as appropriate. In total, 10,225 ACDF, 28,841 PLF, 70,815 THA, and 108,940 TKA patients were analyzed. Most patients in our study sample had preferred provider organization insurance plans (ACDF 70.3%, PLF 66.9%, THA 66.2%, and TKA 67.0%). The mean OOP costs for patients, by procedure, were as follows: ACDF $3,180 (SD = 2,495), PLF $3,166 (SD = 2,529), THA $2,884 (SD = 2,100), and TKA $2,733 (SD = 1,994). Total OOP costs increased significantly from 2014 to 2019 for all procedures (P < 0.0001). Among the insurance plans examined, patients with high-deductible health plans had the highest episodic OOP costs. The ratio of patient contribution (OOP costs) to total insurer contribution (payments from insurers to providers) was 0.07 for ACDF, 0.04 for PLF, 0.07 for THA, and 0.07 for TKA. Among commercially insured patients who underwent elective spinal fusion and major lower extremity joint arthroplasty surgery, OOP costs increased from 2014 to 2019. The OOP costs for elective orthopaedic surgery represent a substantial and increasing financial burden for patients.

Is routine blood typing and screening necessary before primary total hip or knee arthroplasty in the 21st century?

Blood loss warranting transfusion is a relatively rare complication of major-joint arthroplasty procedures like total knee arthroplasty (TKA) and total hip arthroplasty (THA). Despite this rarity, pre-transfusion testing (blood typing, screening, and cross-matching) has become routine. We sought to determine if such routine testing is necessary for patients who undergo a primary TKA or THA by (1) measuring the current rate of intraoperative transfusions in primary TKA and THA patients, (2) identifying risk factors for transfusions, and (3) calculating the costs of such blood typing and screening. We retrospectively examined the records of 992 patients who underwent primary TKA, THA, or unicompartmental knee arthroplasty (UKA) to identify patients requiring intra-operative or in-hospital postoperative transfusions. Demographic and baseline clinical and laboratory data also were collected and analyzed to identify predictors of transfusion. Cost analysis was performed. The rate of intraoperative transfusion was 1.7% (17/992 patients), with rates of 2.1%, 1.6%, and 0% for TKA, THA, and UKA respectively. The in-hospital transfusion rate was 10.3%, with corresponding postoperative transfusion rates of 9.1%, 12.9%, and 2%. The only baseline variable significantly linked to transfusions on multivariable analysis was preoperative hemoglobin level, with preoperative Hgb <12 g/dl predictive of transfusions in both TKA (p=.02) and THA (p=.024) patients. Our study suggests that pre-transfusion testing for all patients undergoing primary UKA, TKA or THA is unnecessary. We recommend reserving routine pre-transfusion testing for patients with preoperative hemoglobin levels below 12 g/dl.

Noninvasive, Wearable, Pulsed Shortwave (Radiofrequency) Therapy for Analgesia following Knee and Hip Arthroplasty: A Case Series

Background: Minimizing pain and opioid requirements following major orthopedic surgery can be challenging. Nonthermal, pulsed, shortwave (radiofrequency) therapy is a noninvasive treatment described previously as a possible analgesic modality following minor surgical procedures. The devices may be applied in a few minutes or less, are simply taped in place over the area of pain, are less expensive than a large bottle of acetaminophen, function for 30 days without any required intervention, may be applied to any part of the body, and produce no side effects-patients cannot detect any sensations from the devices-or substantial risks. Here we present a case series to explore the use of pulsed shortwave therapy for major joint arthroplasty.

CORR Insights®: Does a Prescription-based Comorbidity Index Correlate with the American Society of Anesthesiologists Physical Status Score and Mortality After Joint Arthroplasty? A Registry Study.

CORR Insights®: Does a Prescription-based Comorbidity Index Correlate with the American Society of Anesthesiologists Physical Status Score and Mortality After Joint Arthroplasty? A Registry Study.

The opioid epidemic from the acute care hospital front line.

Prescription opioid use has risen steeply for over two decades, driven primarily by advocacy for better management of chronic non-cancer pain, but also by poor opioid stewardship in the management of acute pain. Inappropriate prescribing, among other things, contributed to the opioid 'epidemic' and striking increases in patient harm. It has also seen a greater proportion of opioid-tolerant patients presenting to acute care hospitals. Effective and safe management of acute pain in opioid-tolerant patients can be challenging, with higher risks of opioid-induced ventilatory impairment and persistent post-discharge opioid use compared with opioid-naive patients. There are also increased risks of some less well known adverse postoperative outcomes including infection, earlier revision rates after major joint arthroplasty and spinal fusion, longer hospital stays, higher re-admission rates and increased healthcare costs. Increasingly, opioid-free/opioid-sparing techniques have been advocated as ways to reduce patient harm. However, good evidence for these remains lacking and opioids will continue to play an important role in the management of acute pain in many patients.Better opioid stewardship with consideration of preoperative opioid weaning in some patients, assessment of patient function rather than relying on pain scores alone to assess adequacy of analgesia, prescription of immediate release opioids only and evidence-based use of analgesic adjuvants are important. Post-discharge opioid prescribing should be contingent on an assessment of patient risk, with short-term only use of opioids. In partnership with pharmacists, nursing staff, other medical specialists, general practitioners and patients, anaesthetists remain ideally positioned to be involved in opioid stewardship in the acute care setting.

Opposing Trends in Total Knee and Hip Arthroplasties for Patients With Rheumatoid Arthritis vs. the General Population-A 14-Year Retrospective Study in Taiwan.

Objective: To determine the trend of incidence rate of total knee arthroplasty (TKA), total hip arthroplasty (THA), and TKA or THA (major joint arthroplasty, MJA) among rheumatoid arthritis (RA) population and compared them with general population (GP) in Taiwan.Methods: Incidence rates and trends of TKA, THA, and MJA were determined over a 14-year period (2000–2013) among RA patients and compared them with GP. RA of patients was diagnosed based on the ACR 1987 criteria and extracted from GP. Subanalyses of incidences of TKA, THA, and MJA by year, 10-year age group, and gender were further conducted for demographic analysis. Patient profiles were extracted from the National Health Insurance Research Database (NHIRD) for interrupted time-series analysis and cohort studies.Results: Patients enrolled were 168,457 receiving TKA, 64,543 receiving THA, and 228,191 receiving MJA surgery. Incidences of TKA, THA, and MJA in RA patients were significantly lower by 49.0, 41.5, and 41.0% compared with concomitantly rises in GP by 131.0, 25.1, and 90.0% among the GP during the study period. The dominant age population for TKA, THA, and MJA were those aged 70–79 years in both GP and RA groups.Conclusions: We found an opposing trend in incidence of TKA, THA, and MJA between RA patients and the GP. The possible influence of pharmacological treatment is implicated for the lower incidence rates of TKA, THA, and MJA surgeries among RA patients.

Is primary total elbow arthroplasty appropriately compensated compared to other major total joint arthroplasty?

BackgroundPrimary total elbow arthroplasty (TEA) is an uncommon operation and performed less frequently than total shoulder (TSA), knee (TKA), and hip (THA) arthroplasty. Despite lower implant survival rates and higher complications rates compared to TSA, TKA, and THA, the Centers for Medicare and Medicaid (CMS) have assigned similar work relative value unit (wRVU) allotments and estimated operative times across all 4 forms of major joint arthroplasty. In this study, we determine temporal trends in CMS wRVU allotments, and operative time estimates for these 4 surgeries and compare actual operative times and postoperative complication rates. MethodsCMS wRVU allotments and estimated operative times were collected from all publicly available CMS publications for primary TEA, TSA, TKA, and TSA. We used the National Quality Improvement Program database from 2010 to 2017 to determine actual operative times for these surgeries. Multiple linear regression analysis was used to compare wRVU/h amongst the 4 surgeries, controlling for patient demographics, comorbidity, and hospital setting. Thirty-day complication rates were also compared. ResultsFrom 2012 to 2017, Medicare observed a 13% decline in total TEA procedures performed in comparison to a 70% increase for TSA and 29% increase in THA. The number of unique providers performing TEA declined (−6%) in comparison to a growth in surgeons performing TSA, TKA, and THA. TEA was associated with the longest operative time (152 ± 57 minutes, P < .0001) and lowest wRVU/h (10.2, P < .0001). TKA and THA had the shortest operative time (90 ± 29 and 90 ± 32, respectively) with the greatest wRVU/h (15.78 and 15.71). TEA remained the lowest wRVU/h procedure even after controlling for patient age, sex, body mass index, hospital setting, and comorbidity (P < .0001). Thirty-day complication rates for all surgeries were low, but TEA had higher rates of wound dehiscence, deep infection, pneumonia, reintubation, pulmonary embolism, and myocardial infarction (all P < .01). ConclusionDespite similar wRVU assignments and operative time estimates for primary TEA, TSA, TKA, and THA; TEA is on average a longer surgery and carries a greater 30-day postoperative risk profile. Although CMS has assessed primary TEA to have similar work and time requirements compared to its counterparts, this procedure may be under-valued in comparison to other forms of major joint arthroplasty. Level of EvidenceLevel III; Economics.

Factors predisposing to thrombosis after major joint arthroplasty.

Total joint arthroplasty is one of the most common options for end stage osteoarthritis of major joints. However, we must take into account that thrombosis after hip/knee arthroplasty may be related to mutations in genes encoding for blood coagulation factors and immune reactions to anticoagulants [heparin-induced thrombocytopenia (HIT)/thrombosis]. Identifying and characterizing genetic risk should help to develop diagnostic strategies or modify anticoagulant options in the search for etiological mechanisms that cause thrombophilia following major orthopedic surgery. To evaluate the impact of patients' coagulation profiles and to study specific pharmacologic factors in the development of post-arthroplasty thrombosis. In 212 (51 male and 161 female) patients that underwent primary total hip arthroplasty (100) or total knee arthroplasty (112) due to osteoarthritis during a period of 1 year, platelet counts and anti-platelet factor 4 (PF4)/heparin antibodies were evaluated pre/postoperatively, and antithrombin III, methylenetetrahydrofolate reductase, factor V and prothrombin gene mutations were evaluated preoperatively. In a minimum follow-up of 3 years, 196 patients receiving either low-molecular-weight heparins (173) or fondaparinux (23) were monitored for the development of thrombocytopenia, anti-PF4/heparin antibodies, HIT, and thrombosis. Of 196 patients, 32 developed thrombocytopenia (nonsignificant correlation between anticoagulant type and thrombocytopenia, P = 0134.) and 18 developed anti-PF4/heparin antibodies (12/173 for low-molecular-weight heparins and 6/23 for fondaparinux; significant correlation between anticoagulant type and appearance of antibodies, P = 0.005). Odds of antibody emergence: 8.2% greater in patients receiving fondaparinux than low-molecular-weight heparins. Gene mutations in factor II or V (two heterozygotes for both factor V and II) were identified in 15 of 196 patients. Abnormal low protein C and/or S levels were found in 3 of 196 (1.5%) patients, while all patients had normal levels of von Willebrand factor, lupus anticoagulant, and antithrombin III. Four patients developed HIT (insignificant correlation between thrombocytopenia and antibodies) and five developed thrombosis (two had positive antibodies and two were heterozygotes for both factor II & V mutations). Thrombosis was not significantly correlated to platelet counts or HIT. The correlation of thrombosis to antibodies, factor II, factor V was P = 0.076, P = 0.043, P = 0.013, respectively. Screening of coagulation profile, instead of platelet monitoring, is probably the safest way to minimize the risk of post-arthroplasty thrombosis. In addition, fondaparinux can lead to the formation of anti-PF4/heparin antibodies or HIT.

Bowel management post major joint arthroplasty: A randomised controlled trial to test two pre-admission bowel regimens

BackgroundThe length of stay for patients undergoing joint arthroplasty has reduced but there is a paucity of knowledge relating to bowel management within this enhanced recovery framework. AimThe study's primary aim was to determine which of two dosage regimens of macrogol (Movicol®) commenced pre-operatively is most effective in facilitating a return to normal bowel function. ProcedureNinety-one eligible patients were randomised to one of three groups: 1) commence macrogol one sachet in the morning for two days prior to surgery; 2) commence macrogol one sachet, morning and evening of the day prior to surgery; or 3) control group. ResultsSeventy-seven percent of patients in group one, and 83% of group two had returned to normal bowel function by one-week post discharge compared to 70% of control patients (p = .470). Participants in group one required less aperients in the week following discharge compared with the other two groups although the result was not statistically significant (p = .060). ConclusionDespite not reaching statistical significance, the results are considered clinically significant. The authors recommend patients commence macrogol one sachet in the morning for the two days prior to admission for major joint arthroplasty and the Murdoch Bowel Protocol® continue to be followed for inpatients.

Analysis of the surface topography of retrieved metal-on-polyethylene reverse shoulder prostheses.

Despite the encouraging short- and medium-term clinical results and increased usage of reverse shoulder replacements, a higher revision rate is documented compared with other major joint arthroplasties. Adverse reaction to polyethylene wear debris is still an important factor which may influence the long-term survival of reverse shoulder arthroplasty. To date, only a small number of retrieval studies of reverse shoulder arthroplasty have reported the different damage modes on polyethylene components, but none have quantified the ex vivo surface roughness on both articulating surfaces. The main purpose of this study was to assess, for the first time, the surface roughness of 13 retrieved metal-on-polyethylene reverse shoulder replacements using a white light profilometre with nanometre resolution. Although no significant relationship was observed between the surface roughness values and patient variables, it was noted that half of the polyethylene components still showed their original machining marks, indicating little change in vivo and that the metallic humeral components in the reversed design configuration showed low values of surface roughness after their time in vivo.

Surgeon proficiency in robot-assisted spine surgery.

Continuous technical improvement in spinal surgical procedures, with the aim of enhancing patient outcomes, can be assisted by the deployment of advanced technologies including navigation, intraoperative CT imaging, and surgical robots. The latest generation of robotic surgical systems allows the simultaneous application of a range of digital features that provide the surgeon with an improved view of the surgical field, often through a narrow portal. There is emerging evidence that procedure-related complications and intraoperative blood loss can be reduced if the new technologies are used by appropriately trained surgeons. Acceptance of the role of surgical robots has increased in recent years among a number of surgical specialities including general surgery, neurosurgery, and orthopaedic surgeons performing major joint arthroplasty. However, ethical challenges have emerged with the rollout of these innovations, such as ensuring surgeon competence in the use of surgical robotics and avoiding financial conflicts of interest. Therefore, it is essential that trainees aspiring to become spinal surgeons as well as established spinal specialists should develop the necessary skills to use robotic technology safely and effectively and understand the ethical framework within which the technology is introduced. Traditional and more recently developed platforms exist to aid skill acquisition and surgical training which are described. The aim of this narrative review is to describe the role of surgical robotics in spinal surgery, describe measures of proficiency, and present the range of training platforms that institutions can use to ensure they employ confident spine surgeons adequately prepared for the era of robotic spinal surgery. Cite this article: Bone Joint J 2020;102-B(5):568-572.

Regional Cerebral Oxygen Saturation Decreases During Primary Hip Arthroplasty: An Analysis of Perioperative Regional Cerebral Oxygenation (rSO2), S100 Calcium-Binding Protein B (S100B) and Glial Fibrillary Acidic Protein (GFAP) Values. A Pilot Study.

BackgroundThe incidence of postoperative cognitive dysfunction (POCD) after major joint arthroplasty is high. In the etiology of POCD, many factors have been cited, including thromboembolic complications. The incidence of cerebral embolization after lower extremity arthroplasty may be as high as 40–60%. The potential events of cerebral embolization could lead to a decrease in the regional cerebral oxygenation (rSO2) and increased serum levels of biochemical markers of brain damage. The objective of the study was to test whether there are any changes in the rSO2 values and serum markers of brain damage in patients who underwent total hip arthroplasty.Material/MethodsFifteen patients who underwent primary hip arthroplasty under spinal anesthesia were analyzed. The rSO2 was monitored using infrared spectroscopy. Biochemical analyses of S100 calcium-binding protein B (S100B) protein and fibrillary acidic protein (GFAP) serum concentrations were performed using immunoassay methods.ResultsThe values of rSO2 decreased during the surgery, but this was not related to mean arterial pressure variations or hemoglobin saturation. The concentration of S100B was increased compared to its preoperative values, and there were no changes in GFAP values. The changes in rSO2 readings correlated with the biomarkers’ levels just after the surgery.ConclusionsOur results suggest that S100B may be a more specific marker of astroglial damage in patients after primary total hip arthroplasty. The decrease in rSO2 readings may be due to micro-thromboembolic events that occurred during the surgery. However, the results of this study are preliminary, and further studies are needed to establish its clinical efficacy.