Introduction. Despite the demonstrated success of total knee arthroplasty (TKA) and higher rates of arthritis and disability from arthritis among minorities, these populations utilize TKA at lower rates than non-Hispanic white patients in the United States. In addition, women present for TKA with more advanced disease prior to TKA than their male counterparts. In order to explore potential reasons for this, we examined the relationship between race, gender, and pre-operative expectations on postoperative outcomes among patients undergoing TKA. Methods. 134 patients scheduled for primary unilateral TKA secondary to moderate to severe osteoarthritis were enrolled in this two-institution prospective study. All patient demographics were collected and recorded in an electronic data registry. In addition, patient reported outcome (PRO) questionnaires, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), HSS Patient Expectation Questionnaire, Social Support Survey, Pain Catastrophizing Scale, Visual Analogue Pain Scale (VAS), Geriatric Depression Scale and European Quality (EQ) of Life 5-Dimensions with EQ VAS were prospectively collected at 4 time points (baseline, 4–8 weeks, 9–14 months, 20–26 months postoperative). Statistical analysis was then conducted among patients of different gender and ethnic background to assess for the effect of these demographic variables on patient expectations and outcomes. Results. Female sex was associated with worse preoperative KOOS scores in symptoms (p=0.021), pain (p=0.019), and activities of daily living (p=0.020). African American race was associated with worse preoperative KOOS scores in pain (p=0.009), activities of daily living (ADLs) (p=0.004), and quality of life (QOL) (p=0.003). However, despite worse pre-operative scores, no statistically significant differences were noted in the aforementioned categories between the groups at any point post-operatively. Conclusion. Our results indicate that female and African American patients undergoing TKA presented with worse pre-operative KOOS scores compared with white male patients. However, outcomes were good among all groups postoperatively, and neither race nor gender was associated with compromised post-operative outcomes in relation to pain, ADLs or QOL. These findings may be valuable in counseling patients and surgeons regarding the value of increase utilization of TKA in these patient populations. Further study is necessary to better understand the lower utilization or later presentation observed in these populations

Aims. To identify variables independently associated with same-day discharge (SDD) of patients following revision total knee arthroplasty (rTKA) and to develop machine learning algorithms to predict suitable candidates for outpatient rTKA. Methods. Data were obtained from the American College of Surgeons National Quality Improvement Programme (ACS-NSQIP) database from the years 2018 to 2020. Patients with elective, unilateral rTKA procedures and a total hospital length of stay between zero and four days were included. Demographic, preoperative, and intraoperative variables were analyzed. A multivariable logistic regression (MLR) model and various machine learning techniques were compared using area under the curve (AUC), calibration, and decision curve analysis. Important and significant variables were identified from the models. Results. Of the 5,600 patients included in this study, 342 (6.1%) underwent SDD. The random forest (RF) model performed the best overall, with an internally validated AUC of 0.810. The ten crucial factors favoring SDD in the RF model include operating time, anaesthesia type, age, BMI, American Society of Anesthesiologists grade, race, history of diabetes, rTKA type, sex, and smoking status. Eight of these variables were also found to be significant in the MLR model. Conclusion. The RF model displayed excellent accuracy and identified clinically important variables for determining candidates for SDD following rTKA. Machine learning techniques such as RF will allow clinicians to accurately risk-stratify their patients preoperatively, in order to optimize resources and improve patient outcomes. Cite this article: Bone Jt Open 2023;4(6):399–407

Aims. This study used an artificial neural network (ANN) model to determine the most important pre- and perioperative variables to predict same-day discharge in patients undergoing total knee arthroplasty (TKA). Methods. Data for this study were collected from the National Surgery Quality Improvement Program (NSQIP) database from the year 2018. Patients who received a primary, elective, unilateral TKA with a diagnosis of primary osteoarthritis were included. Demographic, preoperative, and intraoperative variables were analyzed. The ANN model was compared to a logistic regression model, which is a conventional machine-learning algorithm. Variables collected from 28,742 patients were analyzed based on their contribution to hospital length of stay. Results. The predictability of the ANN model, area under the curve (AUC) = 0.801, was similar to the logistic regression model (AUC = 0.796) and identified certain variables as important factors to predict same-day discharge. The ten most important factors favouring same-day discharge in the ANN model include preoperative sodium, preoperative international normalized ratio, BMI, age, anaesthesia type, operating time, dyspnoea status, functional status, race, anaemia status, and chronic obstructive pulmonary disease (COPD). Six of these variables were also found to be significant on logistic regression analysis. Conclusion. Both ANN modelling and logistic regression analysis revealed clinically important factors in predicting patients who can undergo safely undergo same-day discharge from an outpatient TKA. The ANN model provides a beneficial approach to help determine which perioperative factors can predict same-day discharge as of 2018 perioperative recovery protocols. Cite this article: Bone Joint J 2021;103-B(8):1358–1366

Aims. Liposomal bupivacaine (LB) as part of a periarticular injection protocol continues to be a highly debated topic in total knee arthroplasty (TKA). We evaluated the effect of discontinuing the use of LB in a periarticular protocol on immediate postoperative pain scores, opioid consumption, and objective functional outcomes. Methods. On 1 July 2019, we discontinued the use of intraoperative LB as part of a periarticular injection protocol. A consecutive group of patients who received LB as part of the protocol (Protocol 1) and a subsequent group who did not (Protocol 2) were compared. All patients received the same opioid-sparing protocol. Verbal rating scale (VRS) pain scores were collected from our electronic data warehouse and averaged per patient per 12-hour interval. Events relating to the opiate administration were derived as morphine milligram equivalences (MMEs) per patient per 24-hour interval. The Activity Measure for Post-Acute Care (AM-PAC) tool was used to assess the immediate postoperative function. Results. A total of 888 patients received Protocol 1 and while 789 received Protocol 2. The mean age of the patients was significantly higher in those who did not receive LB (66.80 vs 65.57 years, p = 0.006). The sex, BMI, American Society of Anesthesiologists physical status score, race, smoking status, marital status, operating time, length of stay, and discharge disposition were similar in the two groups. Compared with the LB group, discontinuing LB showed no significant difference in postoperative VRS pain scores up to 72 hours (p > 0.05), opioid administration up to 96 hours (p > 0.05), or AM-PAC scores within the first 24 hours (p > 0.05). Conclusion. The control of pain after TKA with a multimodal management protocol is not improved by the addition of LB compared with traditional bupivacaine. Cite this article: Bone Joint J 2021;103-B(6 Supple A):102–107

Aims. The aim of this study was to screen the entire genome for genetic markers associated with risk for anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) injury. Methods. Genome-wide association (GWA) analyses were performed using data from the Kaiser Permanente Research Board (KPRB) and the UK Biobank. ACL and PCL injury cases were identified based on electronic health records from KPRB and the UK Biobank. GWA analyses from both cohorts were tested for ACL and PCL injury using a logistic regression model adjusting for sex, height, weight, age at enrolment, and race/ethnicity using allele counts for single nucleotide polymorphisms (SNPs). The data from the two GWA studies were combined in a meta-analysis. Candidate genes previously reported to show an association with ACL injury in athletes were also tested for association from the meta-analysis data from the KPRB and the UK Biobank GWA studies. Results. There was a total of 2,214 cases of ACL and PCL injury and 519,869 controls within the two cohorts, with three loci demonstrating a genome-wide significant association in the meta-analysis: INHBA, AEBP2, and LOC101927869. Of the eight candidate genes previously studied in the literature, six were present in the current dataset, and only COL3A1 (rs1800255) showed a significant association (p = 0.006). Conclusion. Genetic markers in three novel loci in this study and one previously-studied candidate gene were identified as potential risk factors for ACL and PCL injury and deserve further validation and investigation of molecular mechanisms. Cite this article: Bone Jt Open 2021;2(6):414–421

Introduction. Antibiotic-impregnated bone cement (AIBC) has been used for decades to treat and prevent post-operative infections in joint arthroplasty. Local delivery of antibiotics may theoretically have a bactericidal effect, however evidence supporting this is controversial and literature suggests its prophylactic use in primary total knee arthroplasty (TKA) is seldom justified. With evolving standards of care, historical data is no longer relevant in addressing the efficacy of AIBC in the contemporary TKA. The purpose of this study was to evaluate outcomes following primary TKA using AIBC and regular non-AIBC by comparing rates of surgical site infection (SSI) and prosthetic joint infection (PJI). Methods. A retrospective review was conducted of all cemented primary TKA procedures from a large institutional database between January 1, 2015 and December 31st, 2016. This identified 6,073 cases, n=2,613 in which AIBC was used and n=3,460 cases using bone cement without antibiotics. Patients were stratified into low risk and high-risk groups based on age (>65 years), BMI (>40), and Charlson Comorbidity Index (CCI; >3). Medical records were reviewed for diagnoses of SSI (skin and superficial wound infections) and PJI (deep joint infections requiring surgery) over a 2-year postoperative period. Univariate analysis and multivariate regression models were used to ascertain the effects of cement type, patient factors (age, gender, BMI, CCI), operative time, and length of stay on infection rates. Additionally, mixed models (adjusted for gender, age, race, BMI, and CCI) were built to account for surgeon variability. Results. The use of AIBC and risk group distributions were equal across the study period and no collinearity was found between the study variables. The SSI rate was 3.0% and the PJI rate was 0.8% in the total study population. Univariate analysis showed there was no significant difference in SSI rates with AIBC compared to non-AIBC (3.3% vs. 2.8%, p=0.278) or in PJI rates (1.0% vs. 0.7%, p=0.203). Multivariate logistic regression analysis adjusted for patient factors, operative time, and length of stay showed no significant difference in SSI rates with a procedure using AIBC compared to non-AIBC (OR=0.90; 95% CI, 0.66–1.23; p=0.515) and no significant difference in PJI rates (OR=1.01; 95% CI, 0.55–1.84; p=0.984). Mixed models also showed no difference in PJI rates with AIBC use after adjusting for surgeon variability as well as patient factors (gender, race, age, BMI, and CCI). Discussion. Prophylactic use of AIBC in primary TKA is not without consequence when considering the significant increase in cost and its potential side effects, namely organism specific antibiotic resistance and mechanical loosening. This study shows that even when adjusted for patient factors, procedure-related factors, and length of stay, there is no clinically significant decrease in infection rates with the use of AIBC in primary TKAs

Introduction. The use of intraoperative liposomal bupivacaine (LB) peri-articular injection has been highly debated for total knee arthroplasty (TKA). We evaluated the effect of an institutional-wide discontinuation of intraoperative LB on immediate postoperative pain scores, opioid consumption, and objective functional outcomes. Material and Methods. Between July 1, 2019 and November 30, 2019, an institutional policy discontinued use of intraoperative LB, while the volume of non-LB with epinephrine was increased from 40-ml to 60-ml. A historical cohort was derived from patients undergoing TKA between January 1, 2019 and June 30, 2019. All patients received the same opioid sparing protocol, minimizing variability in prescribing habits. No adductor canal blocks/pumps were utilized. Nursing documented verbal rating scale (VRS) pain scores were collected from our electronic data warehouse and averaged per patient per 12-hour interval. Opiate administration events were derived as Morphine Milligram Equivalences (MMEs) per patient per 24-hour interval. To assess immediate postoperative functional status, the validated Activity Measure for Post-Acute Care (AM-PAC) tool was utilized. All time events were calculated relative to TKA completion instant. Results. 789 primary TKAs did not receive intraoperative LB, while 888 patients acted as controls. Age was significantly greater in patients that did not receive intraoperative liposomal bupivacaine (66.80±8.97 vs 65.57±9.46; p<.01). Gender, BMI, ASA physical status score, race, smoking status, marital status, surgical time, length of stay and discharge disposition were similar between the two groups (p>.05). Compared to historical controls, discontinuation of LB demonstrated no significant difference in postoperative inpatient VRS pain scores up to 72 hours (p>.05), opioid administration up to 96 hours (p>.05), or AM-PAC scores within the first 24 hours (p>.05). Discussion. Subjective pain scores, opioid consumption, and functional scores were unchanged in the early postoperative period following the discontinuation of intraoperative liposomal delivery of bupivacaine in TKA

Recently, gender-specific designs of total knee replacement have been developed to accommodate anatomical differences between males and females. We examined a group of male and female distal femora matched for age and height, to determine if there was a difference in the aspect ratio (mediolateral distance versus anteroposterior distance) and the height of the anterior flange between the genders. The Hamann-Todd Collection provided 1207 skeletally mature cadaver femora. The femoral length, the anteroposterior height, height of the lateral and medial flanges and the mediolateral width were measured in all the specimens. The mechanical axis of the femur, the cut articular width and the aspect ratio were assessed. Statistical analysis of the effect of gender upon the aspect ratio and the lateral and medial flanges was undertaken, controlling for age, height and race. The mean aspect ratio of male femora was 1.21 (. sd. 0.07) and of female femora it was 1.16 (. sd. 0.06) (p < 0.001). There was no significant difference between male and female specimens in the mean size of the lateral flange (6.57 mm (. sd. 2.57) and 7.02 mm (. sd. 2.36), respectively; p = 0.099) or of the medial flange (3.03 mm (. sd. 2.47) and 3.56 mm (. sd. 2.32), respectively; p = 0.67). Future work in the design of knee prostheses should take into account the overall variability of the anatomy of the distal femur

Aims

In the last decade, perioperative advancements have expanded the use of outpatient primary total knee arthroplasty (TKA). Despite this, there remains limited data on expedited discharge after revision TKA. This study compared 30-day readmissions and reoperations in patients undergoing revision TKA with a hospital stay greater or less than 24 hours. The authors hypothesized that expedited discharge in select patients would not be associated with increased 30-day readmissions and reoperations.

Aims

Revision total knee arthroplasty (rTKA) is a technically challenging and costly procedure. It is well-documented that primary TKA (pTKA) have better survivorship than rTKA; however, we were unable to identify any studies explicitly investigating previous rTKA as a risk factor for failure following rTKA. The purpose of this study is to compare the outcomes following rTKA between patients undergoing index rTKA and those who had been previously revised.

Aims

The diagnosis of periprosthetic joint infection (PJI) can be challenging as the symptoms are similar to other conditions, and the markers used for diagnosis have limited sensitivity and specificity. Recent research has suggested using blood cell ratios, such as platelet-to-volume ratio (PVR) and platelet-to-lymphocyte ratio (PLR), to improve diagnostic accuracy. The aim of the study was to further validate the effectiveness of PVR and PLR in diagnosing PJI.

Aims

The purpose of this study is to determine an individual’s age-specific prevalence of total knee arthroplasty (TKA) after cruciate ligament surgery, and to identify clinical and genetic risk factors associated with undergoing TKA.

Introduction. Robotic assisted Total Knee Arthroplasty (rTKA), provides surgeons with preoperative planning and real-time data allowing for continuous assessment of ligamentous tension and range-of-motion. Using this technology, soft tissue protection, reduced early post-operative pain and improved patient satisfaction have been shown. These advances have the potential to enhance surgical outcomes and may also reduce episode-of-care (EOC) costs for patients, payers, and hospitals. The purpose of this study was to compare robotic assisted vs. manual total knee arthroplasty: 1) 90-day episode-of-care (EOC) costs; 2) index costs; 3) lengths-of-stay (LOS); 4) discharge disposition; and 5) readmission rates. Methods. TKA procedures were identified using the Medicare 100% Standard Analytic Files including; Inpatient, Outpatient, Skilled Nursing (SNF) and Home Health. Members included patients with rTKA or manual TKA (mTKA) between 1/1/2016-3/31/2017. To account for potential baseline differences, propensity score matching (PSM) was performed in a 1-to-5 ratio, robotic to manual based on age, sex, race, geographic division, and comorbidities. After PSM, 519 rTKA and 2,595 mTKA were identified and included for analysis. Ninety-day episode-of-care cost, index cost, LOS, discharge disposition and readmission rates were assessed. Results. Overall 90-day EOC costs were $2,391 less for rTKA patients ($18,568 vs. $20,960; p<.0001). Index facility cost and LOS were also less for rTKA patients by $640 ($12,384 vs. $13,024; p=.0001) and 0.7 days (p<.0001). Additionally, rTKA patients were discharged to SNF less frequently (12.52% vs. 21.70%; p<.0001) and home with health aid (56.65% vs. 46.67%; p<.0001) or self-care (27.55% vs. 23.62%; p=.0566) more frequently and had a 90-day readmission reduction of 33% (p=.0423). Conclusion. Robotic assisted TKA resulted in an overall lower 90-day episode-of-care cost when compared to manual TKA. The 90-day EOC cost savings of rTKA were driven by reduced facility costs, LOS and readmissions, and an economically beneficial discharge destination

Summary. Despite adoption of robust clinical pathways, narcotic administration within the inpatient setting is highly variable and may benefit from the implementation of standardized multi-modal pain management protocols. Introduction. Total knee arthroplasty (TKA) candidates have historically received high doses of opioids within the perioperative period for the management of surgical pain. Healthcare systems have responded by improving opioid prescribing documentation and implementing narcotic-sparing pain protocols into TKA integrated care pathways (ICP). Despite these efforts, there are few technological platforms specifically designed to measure the narcotic burden immediately postoperatively. Here we present an early iteration of an inpatient narcotic administration-reporting tool, which normalizes patient narcotic consumption as an average daily morphine-milligram-equivalence (MME) per surgical encounter (MME/day/encounter) among total knee arthroplasty (TKA) recipients. This information may help orthopaedic surgeons visualize their individual granular inpatient narcotic prescribing habits individually and compared to other surgeons, while taking into consideration patient and procedure specific variables in order to optimize use and curtail unnecessary narcotic prescriptions. Material and Methods. A query of our electronic data warehouse, was performed for patients undergoing elective primary TKA between January 1, 2016 to April 30, 2017. Patients undergoing revision or bilateral procedures were excluded. Patient demographics, inpatient and surgical factors, and inpatient narcotic administration were retrieved. Narcotic type, route and dose were converted into average total Morphine Milligram Equivalents per patient for each post- operative day (figure 1). These MME/day/encounter values were subsequently used determine mean and variance of narcotics prescribed by individual surgeons. A secondary analysis of regional distribution of inpatient narcotic consumption was determined by patient's zip codes. Results. In total, 20 surgeons performed 3,666 primary TKAs. The institutional average narcotic dose administered for a single surgical encounter was 34.45±60.06 MME/day (Figure 1). Average surgeon narcotic prescribing ranged from 18.54 to 42.84 MME/day. Similarly, intra-surgeon variability of narcotic prescribing habits varied from ±20.23 to ±129.02 MME/day. Further visualization of patient breakdown did not demonstrate a trend towards increased narcotic administration or variability for surgeons when compared to race or insurance type. Discussion. Our results suggest that narcotic administration following primary TKA demonstrated a substantial degree of intra-institutional variability for individual surgeons despite the use of standardized clinical pathways. TKA candidates may benefit from the implementation of a more rigid standardization of multi-modal pain management protocols that can control pain while minimizing the narcotic burden. Studies designed to analyze the variability of narcotic use in the post-operative period and determine strategies to minimize inappropriate variation are needed. For any figures or tables, please contact authors directly

Aims

This study investigates whether primary knee arthroplasty (KA) restores health-related quality of life (HRQoL) to levels expected in the general population.

Introduction. Pressure to control health care costs may limit the ability of new implants to enter the market. Customized individually made (CIM) knee implants are produced from CT scans of each patient and may result in improved clinical outcomes based on early data showing less blood loss, reduced bone resection, and better implant function and alignment. Limited economic evidence suggests that the use of CIM technology may result in cost savings, particularly when post-discharge expenses are included. The purpose of this study was to evaluate real-world cost data to determine episode spending in a Medicare population receiving either CIM or off-the-shelf (OTS) implants. Methods. The Yale Center for Musculoskeletal Care and Baker Tilly Healthcare Management reviewed episode expenditures among Medicare beneficiaries who received CIM and OTS implants for TKA between 01/01/2015 and 12/31/2015. Episode costs included the pre-operative CT scan, index TKA procedure, and 12-month post-index spending for inpatient (IP), outpatient (OP), emergency room (ER), skilled nursing facility (SNF), and home health (HH) services. CIM patients were identified through a matching process utilizing de-identified patient demographic and procedural information and the presence of a CT scan 28–365 days before index. OTS patients included those without a CT scan within one year of index. CIM and OTS cohorts were propensity matched to produce comparable cohorts at a one-to-five ratio based on age range, gender, race, geographical location, and comorbidities. Average expenditure was used to calculate one-year costs of care differences between the CIM and the OTS technologies. A Generalized Linear Model (GLM) and two-part model (logistics and GLM) were used to test statistical significance. Results. The study included 4,434 patients (CIM: 739, OTS: 3,695). CIM index hospital expenses were 6.5% less than OTS (CIM: $11,579; OTS: $12,386, p<0.0001). CIM patients were 37.5% less likely to incur SNF costs than OTS patients (CIM: 3.0% vs. OTS: 4.8%; p=0.0241) and had 45.1% lower average SNF expenditures (CIM: $8,882 vs. OTS: $16,183; p=0.0236). There was no difference in the probability of incurring post-index IP costs (CIM: 15.7% vs. OTS: 15.4%; p=0.9437) but average post-index IP expenditures were 27.2% lower among the CIM cohort than OTS (CIM: $12,817 vs. OTS: $17,605; p=0.0008). However, CIM patients were 10.5% more likely to incur OP costs (CIM: 90.9% vs. OTS: 85.7%; p=0.0005) and had 6.1% higher average OP expenditures (CIM: $2,328 vs. OTS: $2,106; p=0.0377). Average 12-month episode spending for the CIM cohort was 8.4% less than the OTS cohort ($1,697 Difference; CIM: $18,585 vs. OTS: $20,280; p<0.0001). Conclusion. Study findings demonstrate that the use of CIM technology can result in significant 12-month episode savings among a Medicare population. The average expenditure differences noted for post-index IP, SNF, and OP cost categories suggest there are differences in required post-operative treatment across the two cohorts. Savings calculated in the analysis is a meaningful reduction for payers. Providers may also benefit from index and episode cost savings through shared savings arrangements. CIM technology should be considered as a method to reduce TKA episode spending

Aims

This study aims to identify the top unanswered research priorities in the field of knee surgery using consensus-based methodology.

Aims

The COVID-19 pandemic led to a swift adoption of telehealth in orthopaedic surgery. This study aimed to analyze the satisfaction of patients and surgeons with the rapid expansion of telehealth at this time within the division of adult reconstructive surgery at a major urban academic tertiary hospital.

Aims

Many patients undergoing total knee arthroplasty (TKA) have severe osteoarthritis (OA) in both knees and may consider either simultaneous or staged bilateral TKA. The implications of simultaneous versus staged bilateral TKA for return to work are not well understood. We hypothesized that employed patients who underwent simultaneous bilateral TKA would have significantly fewer days missed from work compared with the sum of days missed from each operation for patients who underwent staged bilateral TKA.

Aims

Social determinants of health (SDOHs) may contribute to the total cost of care (TCOC) for patients undergoing total knee arthroplasty (TKA). The aim of this study was to investigate the association between demographic data, health status, and SDOHs on 30-day length of stay (LOS) and TCOC after this procedure.