Primary Total Knee Arthroplasty Procedures Research Articles

Recognizing the Sex Disparity in Surgeons Performing Total Knee Arthroplasty

BackgroundThere is an unambiguous sex disparity in the field of orthopaedic surgery, with women making up only 7.4% of practicing orthopaedic surgeons in 2022. This study seeks to evaluate the sex distribution among orthopaedic surgeons engaged in primary total knee arthroplasty (TKA) between 2013 and 2020, as well as the procedural volume attributed to each provider. MethodsWe retrospectively queried the Medicare dataset to quantify all physicians reporting orthopaedic surgery as their specialty and performing primary TKA from 2013 to 2020. Healthcare Common Procedure Coding System codes for primary TKA procedures were used to extract associated utilization and billing provider information. Trend analyses were performed with 2-sided correlated Mann-Kendall tests to evaluate trends in the number of surgeons by sex and the women-to-men surgeon ratio. ResultsDuring the study period, 6,198 to 7,189 surgeons billed for primary TKA. Of this number, an average of 2% were women. The mean number of procedures billed for by men was 39.02/y (standard deviation: 34.54), and by women was 28.76/y (standard deviation: 20.62) (P < .001). There was no significant trend in the number of men or women surgeons who billed for primary TKA during the study period. Trend analysis of the women-to-men ratio demonstrated an increasing trend of statistical significance (P = .0187). ConclusionsThere was a significant upward trend in the women-to-men ratio of surgeons who billed for primary TKA. However, there remains a colossal gender gap, as women only made up 2.4% of surgeons who billed for the procedure. The current study raises awareness of the notable discrepancy in the average number of TKAs performed by women as compared to men. The orthopaedic community should aim to determine ways to increase the number of women arthroplasty surgeons along with the opportunities that women have to perform TKAs.

Oral Postoperative Antibiotic Prophylaxis for Outpatient Total Hip and Knee Arthroplasty: Describing Current Practices

BackgroundDespite an increase in outpatient total hip arthroplasty (THA) and total knee arthroplasty (TKA), large-scale data are lacking on current practice for antibiotic prophylaxis prescribing. We aimed to describe current oral antibiotic prophylaxis practices nationally for outpatient THA and TKA. MethodsThis nationwide retrospective cohort study included primary outpatient THA or TKA procedures in patients aged 18 to 64 years from 2018 to 2021 using a national claims database. Oral antibiotic prescriptions filled perioperatively (defined as 5 days before to 3 days after surgery) were extracted; these were categorized and assumed to represent postoperative prophylaxis. Multivariable logistic regression measured associations between patient and surgery characteristics and perioperative oral antibiotic prophylaxis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) are reported. ResultsOral antibiotic prescriptions were filled in 16.5% of 73,015 outpatient THA and TKA (18.4% of 24,857 THAs, 15.5% of 48,158 TKAs) procedures. Prescriptions were most often for cephalosporins (74.3%), with cephalexin (52.8%), and cefadroxil (19.1%) being the most common. Non-cephalosporin antibiotics prescribed were mainly clindamycin (6.8%), sulfamethoxazole-trimethoprim (6.7%), and doxycycline (6.2%). The odds of receiving oral antibiotic prophylaxis were higher for THA compared to TKA (OR 1.13, 95% CI 1.09 to 1.18, P < .001) and in the presence of obesity, diabetes, and autoimmune conditions (OR 1.08 to 1.13, P < .001 to .01). Ambulatory surgery center procedures also had significantly increased odds of prophylaxis compared to hospital-based outpatient surgeries (OR 2.62, 95% CI 2.51 to 2.73, P < .001). Additionally, regional and time-based variations were noted. ConclusionsPerioperative oral antibiotic prophylaxis prescriptions were filled in only 16.5% of outpatient THA and TKA cases, with variation in the type of antibiotic prescribed. The receipt of any prophylaxis and specific medications was associated with demographic, clinical, and procedure-related characteristics. Follow-up research will evaluate associations with infection risk reduction.

Effect of preservation of Hoffa's fat pad on patellar height in primary total knee arthroplasty procedures.

We have previously reported our experience of the effect of complete excision of Hoffa's fat pad on patella height post TKR. In this study, we compared the change of patellar height post TKR before and after the senior author changed his practice to preserving Hoffa's fat pad. This was a retrospective analysis of a prospective series of TKRs performed or directly supervised by the senior author. In Group 1 were 72 patients performed before April 2011 who had complete excision of Hoffa's fat pad to maximise exposure during the procedure. In Group 2 were 138 patients performed after April 2011 who had the minimum excision of Hoffa's fat pad to allow adequate surgical exposure. The surgical technique and rehabilitation protocol were identical in all other respects. Patellar height was assessed using the Caton-Deschamps Index both immediately postoperative and at a minimum follow up of 1year. Group 1 included 28 males, 44 females with mean age 68.36years. The mean CDI in this group changed from 0.54 immediately post-operatively to 0.46 at minimum one year follow-up (P = 0.001) indicating progressive patella baja. Group 2 included 56 males, 82 females with mean age 65years. The mean CDI changed from 0.67 immediately post-operative to 0.68 at minimum one year post follow-up (P = 0.32) indicating no statistically or clinically relevant post-operative change in patellar height. Total excision of Hoffa's fat pad is associated with progressive post-operative patella baja. This can be avoided by resecting the minimum amount of fat pad to allow adequate exposure during the procedure.

The Utilization of Press-Fit Total Knee Arthroplasty is Not Evenly Distributed: A National Registry Review.

This study evaluates trends of cemented versus press-fit total knee arthroplasty (TKA). We hypothesized that press-fit TKA is more common in younger and obese patients. There may also be racial, geographic, and institutional variation. The American Joint Replacement Registry was used to conduct a retrospective review of primary TKA procedures for osteoarthritis in the United States between January 2019 and March 2022. The objective was to identify differences in incidence, demographics, body mass index (BMI), Charlson Comorbidity Index (CCI), and institutional teaching status (teaching vs. non-teaching) between press-fit and cemented TKAs. Two hundred ninety-seven thousand four hundred two patients (61% female, average age 68 years, 88.3% White) underwent cemented TKA versus 50,880 patients (52% female, average age 65 years, 89% White) underwent press-fit TKA. Overall, 20.8% of press-fit versus 19.9% of cemented TKA had a BMI of 35 to 39.9 and 15.2% of press-fit versus 12.5% of cemented TKA had BMI >40 ( P < 0.001). Patients undergoing press-fit TKA were less likely Black (OR = 0.727; P < 0.0001), Asian (OR = 0.651, P < 0.0001), and Native Hawaiian/other Pacific Islander (OR = 0.705, P < 0.02) with White as the reference group. Northeastern and Southern United States were more likely to use press-fit TKA than the Midwest (OR = 1.89 and OR = 1.87, P < 0.0001) and West (OR = 1.67; and OR = 1.65; P < 0.0001). Press-fit TKA incidence in 2019 was 9.9% versus 20.6% in 2022 ( P < 0.001). Press-fit TKA is increasingly more common in Northeastern and Southern United States, and patients are older than expected. Patients with BMI >35 had a slightly higher rate of undergoing press-fit than cemented TKA. Notable racial differences also exist. Additional research addressing racial disparities and evaluating longevity of press-fit designs is needed.

Antibiotic prophylaxis prior to colonoscopy with biopsy does not decrease risk of prosthetic joint infection in total knee arthroplasty recipients

IntroductionProsthetic joint infection (PJI) risk continues to receive much attention given its associated morbidity and costs to patients and healthcare systems. It has been hypothesized that invasive colonoscopies may increase the risk of PJI. However, the decision to administer antibiotic prophylaxis lacks clinical guidance. In this study we aimed to compare PJI rates in patients undergoing colonoscopies with and without antibiotic prophylaxis against a control group, analyzing PJI occurrences at 90 days, 6 months, 9 months, and 1-year post-procedure and (2) assess the impact of antibiotic prophylaxis on PJI rates to inform clinical guidelines. MethodsWe queried a national, all-payer database to identify all primary total knee arthroplasty procedures without prior history of PJI between January 2010 and October 2020 (n = 1.9 million). All patients who had a diagnosis of PJI within one year of index procedure were excluded. There were three cohorts identified: colonoscopy with biopsy without antibiotic prophylaxis; colonoscopy with biopsy with antibiotic prophylaxis; and a control of no prior colonoscopy. Both colonoscopy cohorts were slightly younger and had higher comorbidities than the controls. The PJI diagnoses were identified at four separate time intervals within one-year after colonoscopy: 90-days; 6-months; 9-months; and 1-year. Chi-square analyses with odds ratios (ORs) and 95% confidence intervals were conducted for PJI rates between groups at all time-points. ResultsAmong all cohorts, no significant differences in PJI rates were found at 90-days (P = 0.459), 6-months (P = 0.608), 9-months (P = 0.598), and 1-year (P = 0.330). Similarly, direct comparison of both colonoscopy groups, with and without antibiotic prophylaxis, demonstrated no PJI rate differences at 90-day (P = 0.540), 6-months (P = 0.812), 9-months (P = 0.958), and 1-year (P = 0.207). Ranges of ORs between the colonoscopy cohorts were 1.07–1.43. ConclusionInvasive colonoscopy does not increase the risk of PJI in patients who have pre-existing knee implants. Furthermore, antibiotic prophylaxis may not be warranted in patients undergoing colonoscopy who have a planned biopsy.

Clinical and Radiological Outcomes of Computer-Assisted Navigation in Primary Total Knee Arthroplasty for Patients with Extra-articular Deformity: Systematic Review and Meta-Analysis.

Computer-assisted navigation surgery (CAS) during primary total knee arthroplasty (TKA) may help improve outcomes for patients with extra-articular deformity (EAD); however, this has not been extensively studied. Therefore, we aimed to investigate the clinical and radiological outcomes following primary TKA using CAS in patients with EAD. We searched Medline, Embase, and the Cochrane Library up to March 3, 2023 for studies investigating surgical outcomes of using the navigation system for TKA to treat patients with EAD. From 14 studies, 539 knees with EAD that underwent navigation TKA were enrolled. We investigated the knee range of motion (ROM), outcome scores at final follow-up (Knee Society Score [KSS] and Knee Functional Score [KFS]), and pre- and postoperative mechanical hip-knee-ankle (mHKA) angle using lower extremity scanogram. The meta-analysis was based on the single-arm method, and all data were pooled using a random-effects model. Following our meta-analyses, the mean knee ROM changed from 87.0° (95% confidence interval [CI], 75.9°-98.1°) preoperatively to 109.4° (95% CI, 97.9°-120.8°) postoperatively. The adjusted KSS was 93.45 points (95% CI, 88.36-98.54 points), and the adjusted KFS was 91.57 points (95% CI, 86.80-96.33 points) in knees with EAD that underwent CAS-TKA. As a radiological outcome, the mHKA angle changed from 169.53° (95% CI, 166.90°-172.16°) preoperatively to 178.81° (95% CI, 178.31°-179.30°) postoperatively. CAS-TKA yielded positive clinical results and demonstrated a satisfactory alignment of the lower limb's mechanical axis. CAS-TKA showed promise for primary TKA procedures, demonstrating favorable clinical and radiological outcomes even in complex cases involving EAD.

Modern robotics platform associated with reduced 90-day complications in hospital setting

BACKGROUND: Early complications in total knee arthroplasty (TKA) associated with modern robotics platforms integrated with digital balancing technology have not been investigated. OBJECTIVE: The objective was to compare 90-day complication rates between a manual technique and a modern robotic-assisted ligament balancing TKA platform. METHODS: 895 primary TKA procedures from a single surgeon were retrospectively reviewed (614 manual TKA, 281 using a modern robotics platform with an integrated digitally controlled ligament balancing device). Post-operative complications within the 90-day episode of care were recorded by the Michigan Arthroplasty Registry Collaborative Quality Initiative. Differences in complication rates between techniques were further divided into inpatient hospital, outpatient hospital, and ambulatory surgery center (ASC) cohorts. RESULTS: In the pooled hospital cohort and inpatient hospital cohort, ‘Return to OR’ was significantly lower for the robotic assisted group (1.3% vs 5.2% and 0% vs 4.9%, respectively, p&lt; 0.0370). Specifically, the need for manipulation under anesthesia (MUA) was reduced for the robotics group (0.0% vs 2.5%, p= 0.0352). No differences in overall complication rate or cause of complication was found between manual and robotics cases for the hospital outpatient and ASC cohorts (p⩾ 0.68). CONCLUSION: Within the hospital setting, robotic assisted ligament balancing technology was associated with reduced 90-day postoperative complications for ‘Return to OR’ and MUA.

Development of application and surgical technique of total knee arthroplasties: a systematic comparative analysis using worldwide registers

PurposeThe aim was to compare total knee arthroplasty (TKA) between countries with regard to epidemiologic data and surgical technique by the use of worldwide registers and compare findings with a previous report after one decade.MethodsA systematic search was carried out in November 2022 and compared to previous reports from 2010. We extracted data regarding implanted TKAs, patients’ age distribution, procedure types, fixation and revision rates. After identification of 28 national arthroplasty registers, 8of them, namely Australia, Canada, Denmark, England and Wales, New Zealand, Norway, Scotland and Sweden, offered sufficient data and were included in final analysis.ResultsA large variation was found in the annual number of implantations per 100,000 inhabitants with a range from 77 to 210.2 (mean 132.8). The fixation type varied strongly as well, e.g. over 95% of totally cemented TKAs in Sweden versus 61.2% cemented fixation in Denmark. Another significant difference was the use of patellar resurfacing in TKA, ranging from 47.3% (Canada) using a patellar button in TKA to less than 5% (Sweden). Within the period of one decade, the mean overall number of annual implantations increased (10%), whilst relative number of revisions decreased, the use of cemented TKA decreased from 87 to 74%, and the use of patella button remained largely inhomogeneous.ConclusionComparison of arthroplasty registers revealed large differences regarding the annual number of primary TKAs per inhabitant as well as primary TKA procedure types with an increase of annual implantations, decrease of relative number of revisions, and a decrease of the use of cemented systems over the period of one decade.

The Effect of Surgeon Volume on Revision for Periprosthetic Joint Infection: An Analysis of 602,919 Primary Total Knee Arthroplasties.

Periprosthetic joint infection (PJI) is a devastating complication of total knee arthroplasty (TKA). An association between low surgeon volume and higher rates of infection following primary TKA has been suggested. The purpose of the present study was to determine if there was a relationship between surgeon volume and the rate of revision for infection after primary TKA. We searched the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to identify all primary TKA procedures that were performed for the treatment of osteoarthritis from September 1, 1999, to December 31, 2020, and were subsequently revised because of infection. Surgeon volume was defined as the annual volume of procedures performed by a surgeon during the same year in which the primary TKA (which was subsequently revised for infection) was performed. Surgeon volume was defined as <25, 25 to 49, 50 to 74, 75 to 99, or ≥100 primary TKA procedures/year. The cumulative percent revision (CPR) for infection was determined with use of Kaplan-Meier estimates. Cox proportional hazards methods were used to compare rates of revision for infection by surgeon volume, with subanalyses for patellar resurfacing and polyethylene use. Further analyses for patients <65 years of age and male patients were undertaken. Overall, 602,919 primary TKA procedures were performed for the treatment of osteoarthritis, of which 5,295 were revised because of infection. High-volume surgeons (≥100 TKAs/year) had a significantly lower rate of revision for infection, with a CPR at 1 and 19 years of 0.4% (95% confidence interval [CI], 0.3 to 0.4) and 1.5% (95% CI, 1.2 to 2.0), respectively, compared with 0.6% (95% CI, 0.5 to 0.7) and 2.1% (95% CI, 1.8 to 2.3), respectively, for low-volume surgeons (<25 TKAs/year). Hazard ratios (HRs), adjusted for age and sex, comparing these 2 groups varied, depending on the time point, between 3.07 (95% CI, 2.02 to 4.68) and 1.44 (95% CI, 1.26 to 1.63) but remained significant (p < 0.001). When the analysis was adjusted for age, sex, American Society of Anesthesiologists (ASA) classification, and body mass index (BMI), there remained an increased risk of revision for PJI for all lower surgeon volume levels in comparison with the high- surgeon-volume group (≥100 TKAs/year). The results were similar when stratified by patellar resurfacing and cross-linked polyethylene (XLPE) and adjusted for age and sex. High-volume surgeons had lower rates of revision for infection. A better understanding of how surgical volume contributes to decreasing this complication is important and requires in-depth study. Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

How Sterile Are Our Operating Rooms? A Comparison of Air Quality During Primary TKA and THA

Introduction: Airborne Biologic Particles (ABPs) are a potential risk factor for infection following total joint arthroplasty. Factors such as temperature and humidity may affect the number of ABPs which can increase the risk of infection. Comparisons of ABP count between Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA) have yet to be made. Our study examines the differences in ABP count between primary THA and TKA procedures. Methods: We analyzed all primary TJA procedures done within the same OR at an academic institution from April 2019 to June 2020. All procedures between the dates of March 15, 2020 – May 4, 2020 were excluded to avoid COVID-related confounding. Intraoperative measurements of temperature, humidity, and ABP count per minute were recorded. A report containing surgical data from the same time was generated using the institution’s Electronic Health Records (EHR) system and cross-referenced to the intraoperative measurements using procedure start and end times. ABP was calculated as an average ABP count per minute. Descriptive statistics were used to evaluate differences in variables of interest. P-values were calculated using t-test for continuous variables and chi square for categorical values. Results: A total of 168 cases were included in the study, comprised of 98 (58.3%) primary THA and 70 (41.7%) primary TKA. No significant differences in room temperature or particle counts across all particle sizes were found between THA and TKA groups. Similarly, time spent in the room was not significantly different between THA and TKA. The only variable that was significantly different between the two groups was average relative humidity, with higher humidity in the THA group (46.9% + 7.56 vs 44.4% + 8.02, p=0.008). Conclusion: There were no significant differences in temperature or particle count between primary THA and primary TKA procedures, suggesting OR air quality was similar between the two procedure types. Further investigation including additional variables such as OR size, airflow patterns, and different procedure types should be performed to better characterize the role of ABPs in air quality and infection risk.

In meeting the increasing demands for total knee arthroplasty, can we achieve high levels of quality care in a small community hospital? A mixed-methods study.

Small community hospitals (SCHs) help meet the demand for total knee arthroplasty (TKA). This mixed-methods study compares outcomes and analyses of environmental differences following TKA at a SCH and a tertiary care hospital (TCH). Quantitative: A retrospective review of 352 propensity-matched primary TKA procedures at both a SCH and a TCH, based on age, body mass index, and American Society of Anesthesiologists class, was completed. Groups were compared by length of stay (LOS), 90-day emergency department visits, 90-day readmissions, reoperations, and mortality. Qualitative: Based on the Theoretical Domains Framework, seven prospective semistructured interviews were performed. Interview transcripts were coded and belief statements were generated and summarized by two reviewers. Discrepancies were resolved by a third reviewer. Quantitative: The average LOS for the SCH was significantly shorter than that for the TCH (2.0 ± 0.2 vs. 3.6 ± 2.7 days; p < 0.001), a difference that persisted following a subgroup analysis of ASA I/II patients (2.0 ± 0.2 vs. 3.2 ± 2.2; p < 0.001). There were no significant differences in other outcomes. Qualitative: The main themes that revolved around a higher case load for physiotherapy at the TCH resulted in patients waiting longer to be mobilized after surgery. Patient disposition also affected their discharge rates. Given the increasing demand for TKA, the SCH represents a viable option to increase capacity, while reducing LOS. Future directions to reduce LOS include addressing social barriers to discharge and patient prioritization for assessment by allied health services. When TKA is performed by the same set of surgeons, the SCH provides quality care with a shorter LOS and comparable with urban hospitals, and this can be attributed to the differences in resource utilization in the two hospital settings.

THE EFFECT OF SURGEON VOLUME ON REVISION FOR DEEP PERIPROSTHETIC JOINT INFECTION: AN ANALYSIS OF 602,919 PRIMARY TOTAL KNEE ARTHROPLASTIES

Deep infection is a devastating complication of total knee arthroplasty (TKA). This study aimed to determine if there was a relationship between surgeon volume and the incidence of revision for infection after primary TKA.Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) from 1 September 1999 to 31 December 2020 for primary TKA for osteoarthritis that were revised for infection. Surgeon volume was defined by the number of primary TKA procedures performed by the surgeon in the year the primary TKA was performed and grouped as &lt;25, 25-49, 50-74, 75-99, &gt;100 primary TKA procedures per year. Kaplan Meir estimates for cumulative percent revision (CPR) and Cox Proportional Hazard Ratios were performed to compare rates of revision for infection by surgeon volume, with sub-analyses for patella and polyethylene use, age &lt;65 years and male gender.5295 of 602,919 primary TKA for osteoarthritis were revised for infection. High volume surgeons (&gt;100 TKA/year) had a significantly lower rate of revision for infection with a CPR at 1 and 17 years of 0.4% (95% CI 0.3, 0.4) and 1.5% (95% CI 1.2, 2.0), respectively, compared with 0.6% (95% CI 0.5, 0.7) and 2.1% (95% CI 1.8, 2.3), respectively, for low volume surgeons (&lt;25 TKR/year). Differences between the high-volume group and the remaining groups remained when sub-analysis for age, gender, ASA, BMI, patella resurfacing and the use of cross-linked polyethylene (XLPE).High volume surgeons have lower rates of revision for infection in primary TKA.

Association of Quality of Care With Where Veterans Choose to Get Knee Replacement Surgery

Recent legislation expanded veterans' access to Veterans Health Administration (VA)-purchased care. Quality should be considered when choosing where to get total knee arthroplasty (TKA), but currently available quality metrics provide little guidance. To determine whether an association exists between the proportion of TKAs performed (vs purchased) at each VA facility and the quality of care provided (as measured by short-term complication rates). This 3-year cohort study used VA and community care data (fiscal year 2017 to fiscal year 2019) from the VA's Corporate Data Warehouse. Complications were defined following the Centers for Medicare and Medicaid Services' methodology. The setting included 140 VA health care facilities performing or purchasing TKAs. Participants included veterans who had 43 371 primary TKA procedures that were either VA-performed or VA-purchased during the study period. Of the 43 371 primary TKA procedures, 18 964 (43.7%) were VA-purchased. The primary outcome was risk-standardized short-term complication rates of VA-performed or VA-purchased TKAs. The association between the proportion of TKAs performed at each VA facility and quality of VA-performed and VA-purchased care was examined using a regression model. Subgroups were also identified for facilities that had complication rates above or below the overall mean complication rate and for facilities that performed more or less than half of the facility's TKAs. Among the study sample's 41 775 veterans who underwent 43 371 TKAs, 38 725 (89.3%) were male, 6406 (14.8%) were Black, 33 211 (76.6%) were White, and 1367 (3.2%) had other race or ethnicity (including American Indian or Alaska Native, Asian, and Native Hawaiian or other Pacific Islander); mean (SD) age was 66.9 (8.5) years. VA-performed and VA-purchased TKAs had a mean (SD) raw overall short-term complication rate of 2.97% (0.08%). There was no association between the proportion of TKAs performed in VA facilities and risk-standardized complication rates for VA-performed TKAs, and no association for VA-purchased TKAs. In this cohort study, surgical quality did not have an association with where veterans had TKA, possibly because meaningful comparative data are lacking. Reporting local and community risk-standardized complication rates may inform veterans' decisions and improve care. Combining these data with the proportion of TKAs performed at each site could facilitate administrative decisions on where resources should be allocated to improve care.

Clinical Outcome of Different Post-operative Prophylactic Strategies on Symptomatic Venous Thromboembolism after Total Knee Arthroplasty

IntroductionThe objective of this study was to evaluate the use of different post-operative prophylactic strategies on the rates of symptomatic venous thromboembolic events (VTE) incidence after primary total knee arthroplasty (TKA).MethodsA retrospective study of patients who underwent primary TKA procedure was performed from January 2015 through July 2020. Outcomes examined prophylaxis medication used during inpatient and outpatient care, amount of medication, length of medication, complications occurring within 90 days post-operatively, including symptomatic VTE (deep venous thrombosis (DVT), and pulmonary embolism (PE)), gastrointestinal (GI) bleeding requiring medical attention, change in management protocols after post-operative complications, and mortality.ResultsIn total, 5,663 cases were included (mean age 66 ± 10 years, mean BMI 34.1 ± 7.1kg/m2). The overall post-operative complication rate was 0.9% (DVT: 0.5%, PE: 0.3%, VTE: 0.04%, and GI bleeding: 0.09%). Enoxaparin use as inpatient anticoagulation medication was reduced significantly (67% vs. 13%, p < 0.001), and apixaban was increased significantly (6% vs. 49%, p < 0.001). Average hospital stays were reduced significantly among the years (3 ± 2 days vs. 2 ± 1 days, p < 0.001), and complication rates were not significantly different between the five years (~1%, p < 0.001). Most post-operative complications occurred on either aspirin 325 mg (36%) or apixaban (26%). However, the relative risk ratio results indicating that utilization of warfarin, rivaroxaban, and aspirin 81 mg as outpatient anticoagulation medication were more likely to increase the risk of symptomatic VTE incidence compared to other anticoagulants. The average time of complication detected was 21 ± 21 days (range: 1 – 87 days). More than 54% of complication events occurred after the patient had completed their medication (enoxaparin, rivaroxaban, and apixaban).ConclusionsThe observed incidence of symptomatic VTE in this study was similar to previous studies regardless of the type of post-operative inpatient or outpatient prophylaxis prescribed. The ultimate choice of prophylaxis should remain with the treating physician and their knowledge of a particular patient’s medical history.

Primary total knee arthroplasties under the Brazilian Public Health Unic System (SUS) - Number of procedures, regional distribution, hospitalization costs, average length of hospital stay and mortality (2012-2021)

The aim of this study was to describe the number and regional distribution of hospital admission authorization (AIH), hospitalization costs, average length of stay (LOS), and mortality rates related to primary total knee arthroplasty (TKA) procedures funded by the Brazilian Public Health Unic System (SUS) from 2012 to 2021. A cross-sectional descriptive study on the number and regional distribution of AIH, hospitalization costs, average LOS, and mortality rates related to primary TKA procedures funded by the SUS from 2012 to 2021 was done. As results, 65,602 AIH were released in the evaluated period; in 2020 and 2021 there was a sharp decrease of procedures, probably due to the COVID-19 pandemic. The total value spent in the evaluated period was of 271,297,010.60 BRL. The average LOS was of 4.15 days. The absolute number of deaths was of 103, with 0.16% of mortality rate. It was concluded that the number and regional distribution of AIH was of 37,370 (57%) to the Southeast; 18,907 (29%) to the South, 5,250 (8%) to the Northeast; 2,758 (4%) to the Midwest and 1,317 (2%) to the North, totaling 65,602 admissions, with a total expenditure of 271,297,010.60 BRL (156,252,541.60 BRL in Southeast, 77,150,946.31 BRL in South, 21,194,955.07 BRL in Northeast, 12,077,393.69 BRL in Midwest and 4,621,173.96 BRL in North). The average LOS (in days) was of 4.15 (4.15 in Southeast; 3.83 in South; 4.6 in Northeast; 4.81 in Midwest; and, 5.71 in North). The mortality rate was of 0.16% (Southeast=0,14%; South=0,1%; Northeast=0,16%; Midwest=0,17%; and North=0,14%).

Trends in Polyethylene Design and Manufacturing Characteristics for Total Knee Arthroplasty: An Analysis From the American Joint Replacement Registry.

Advances in polyethylene bearing characteristics have led to various options for total knee arthroplasty. We examine trends in use of polyethylene in the United States. An analysis of American Joint Replacement Registry data from 2012 to 2019 for primary total knee arthroplasty procedures was conducted. Design and manufacturing characteristics were obtained and validated in the American Joint Replacement Registry dataset. Polyethylene bearing design and manufacturing use characteristics were compared by year, gender, age group, and geographic region of the procedure. Descriptive analysis was performed. We identified 993,292 cases over the study period. In total, 791,233 (80%) cases had complete device data available and were included in analysis. In addition, 366,280 (49.4%) cases utilized minimally stabilized bearings compared to 374,809 (50.6%) for posterior-stabilized bearings. Posterior-stabilized use was stable over the study period and highest in the Northeast (64.5%; P < .0001). Cruciate-retaining use decreased from 29.7% to 20.2% and anterior-stabilized use increased from 17.4% to 25.2%. Conventional polyethylene use decreased from 42.8% to 21.9%, and was highest in the 81+ age group (37.8%; P < .0001) and Northeast (43.0%; P < .0001). Highly cross-linked polyethylene (HXLPE) with antioxidant use increased from 9.08% to 31.8%, while HXLPE without antioxidant use remained constant. There was an increase in use of anterior-stabilized and pivot bearings and an increase in use of HXLPE with antioxidant. Additionally, there were noted age group and regional differences in the use of various bearings. Further study should evaluate if these changing utilization trends are related to clinical outcomes, or due to regional training, preferences, or manufacturer pressures. Level III, retrospective.

Is obesity associated with short-term revision after total knee arthroplasty? An analysis of 121,819 primary procedures from the Dutch Arthroplasty Register

BackgroundThe prevalence of obesity is increasing. The association with knee osteoarthritis is well documented, resulting in the population requesting total knee arthroplasty (TKA) for invalidating symptoms to be heavier in nature. The purpose of the current analysis was to assess the association between preoperative body mass index (BMI) and short-term revision rate after TKA. The secondary aim was to investigate the influence of implant fixation method on the association between BMI and survivorship. MethodsThis is a retrospective analysis of prospectively collected registry data (Dutch Arthroplasty Register; LROI). All primary TKA procedures in patients >18 years of age with registered BMI were selected (n = 121,819). Non-obese patients (BMI 18–25) were compared with overweight (BMI 25–30) and class I–III obese (BMI >30, >35, >40) patients. Crude all-cause revision rates were calculated using competing risk analysis. Adjusted hazard ratios (HRs) were determined with Cox multivariable regression analyses for all-cause, septic and aseptic revision and secondary patellar resurfacing. ResultsRevision rates were 3.3% for non-obese patients, 3.5% for overweight patients, 3.7% for class I obese patients, 3.6% for class II obese patients and 3.7% for class III obese patients. Class III obese patients had a significant higher risk for septic revision compared with non-obese patients (HR 1.53, 95% confidence interval (CI) 1.06–2.22). Class I obese patients had a higher risk for secondary patellar resurfacing (HR 1.52, 95% CI 1.12–2.08). All-cause and aseptic revision rates were similar between BMI groups. ConclusionsObesity appeared to be associated with some short-term revision risks after TKA, but was not associated with an overall increase in revision rate.

Preoperative Sedative Use and Other Risk Factors for Continued Narcotic Use After Total Knee Arthroplasty: A Comprehensive Analysis of a Mandatory Database.

Opioids are used for pain control after total knee arthroplasty (TKA) and carry risk for abuse. Mandatory statewide databases have been created to monitor their use. The goal of this study was to identify patient risk factors for prolonged opioid use after TKA. The authors retrospectively reviewed a consecutive series of 676 primary TKA procedures performed between January 2017 and July 2017. Information on fulfillment of narcotic, sedative, benzodiazepine, and stimulant prescriptions was obtained from the Pennsylvania State Controlled Substance Monitoring website 6 months before and 1 year after the procedure. Bivariate and multivariate analyses were used to identify risk factors for the need for a second prescription and opioid use for longer than 6 months. Of this cohort, 30.3% used preoperative opioids, 60.5% filled a second opioid prescription, and 11.8% continued opioid use for longer than 6 months. Patients who had opioid use before the index procedure had more than 3-fold (odds ratio [OR], 3.29; P<.001) increased odds of filling a second opioid prescription and 8-fold (OR, 8.05; P<.001) increased odds of postoperative opioid use for longer than 6 months. Multivariate analysis was used to identify independent risk factors for requiring a second prescription, including discharge to a rehabilitation facility (OR, 2.77), bilateral procedures (OR, 1.88), preoperative narcotic use (OR, 1.70), and younger age (OR, 0.95). Independent risk factors for narcotic use for longer than 6 months included preoperative sedative (OR, 3.30) or narcotic use (OR, 1.49). This study identified several risk factors associated with prolonged narcotic use after TKA, including preoperative sedative use, and determined their relative weight. [Orthopedics. 2021;44(1):e50-e54.].

The Utility of Obtaining a Complete Blood Count After Total Knee Arthroplasty in the Era of Tranexamic Acid.

Questioning the routine use of postoperative laboratory tests is a strategy to combat rising health care costs. The goal of this study was to determine the utility and cost of routine postoperative complete blood count (CBC) testing after primary total knee arthroplasty (TKA) in the era of tranexamic acid (TXA). This retrospective chart review identified patients who underwent primary TKA performed by a single surgeon at a single private institution during a 2-year period. All patients received TXA intraoperatively. Exact tests were used to determine whether there was a significant difference in transfusion rates between patients with and without preoperative anemia. Of 628 primary TKA procedures, 390 patients (62.10%) had anemia postoperatively. However, only 1 patient (0.16%) required transfusion. A total of 956 CBC tests were performed without intervention, at a total cost of $116,804.08. In addition, 1 of 26 patients with preoperative anemia vs 0 of 602 patients without preoperative anemia required transfusion (P=.04). Healthy patients undergoing primary TKA who receive TXA do not require postoperative CBC. This change has the potential to reduce this laboratory cost by more than 97% compared with the current practice of obtaining postoperative CBC testing for every patient undergoing TKA. Only patients with preoperative anemia should undergo postoperative CBC testing to help to identify those who require transfusion. The potential health care savings associated with eliminating routine postoperative CBC testing are substantial and should be considered by arthroplasty surgeons. [Orthopedics. 2021;44(1):e26-e30.].

Completeness and capture rate of publicly funded arthroplasty procedures in the New Zealand Joint Registry.

Registry-based studies have become more common due to the availability of a large study cohort. However, the validity of findings is dependent on the completeness of the registry. This study aimed to validate the capture rate of the New Zealand Joint Registry (NZJR) by matching procedures that have been recorded separately via clinical coding by the New Zealand Government's National Surgical Site Infection Improvement Programme (SSIIP). The National Health Index, a unique identification code for all patients, was combined with the arthroplasty procedure performed (primary total knee arthroplasty (TKA), primary total hip arthroplasty (THA), revision TKA or revision THA) and operation side. Publicly funded procedures recorded in the NZJR were matched with procedures recorded by the SSIIP on a record-by-record basis. This identified the total number of arthroplasty procedures performed in New Zealand, which was used as the denominator value to calculate the procedure capture rate of the NZJR. Between 2013 and 2018, 24 556 primary TKA, 28 970 primary THA, 2107 revision TKA and 4263 revision THA procedures were recorded by both datasets. The NZJR recorded 95.5% of primary TKA procedures, 96.3% of primary THA procedures, 97.1% of revision TKA procedures and 95.2% of revision THA procedures. The NZJR recorded >95% of publicly funded arthroplasty procedures. In contrast, there were inaccuracies in clinical coding by hospitals, particularly with revision procedures, demonstrating the benefits of an arthroplasty registry. However, data recorded by an infection surveillance programme may supplement arthroplasty registry data to strengthen the quality of research.