Faculty Bibliography

BACKGROUND:The most common treatment for periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is a 2-stage revision. Few studies have compared different articulating spacer constructs. This study compares the outcomes of real-component and all-cement articulating spacers for TKA PJI treatment. METHODS:This retrospective observational study examined the arthroplasty database at 3 academic hospitals for articulating spacers placed for TKA PJIs between April 2011 and August 2020. Patients were categorized as receiving a real-component or an all-cement articulating spacer. Data on demographics, surgical information, and outcomes were collected. RESULTS:One-hundred sixty-four spacers were identified: 72 all-cement and 92 real-component spacers. Patients who received real-component spacers were older (67 ± 10 vs 63 ± 12 years; P = .04) and more likely to be former smokers (50.0% vs 28.6%; P = .02). Real-component spacers had greater range of motion (ROM) after Stage 1 (84° ± 28° vs 58° ± 28°; P < .01) and shorter hospital stays after Stage 1 (5.8 ± 4.3 vs 8.4 ± 6.8 days; P < .01). There was no difference in time to reimplantation, change in ROM from pre-Stage 1 to most recent follow-up, or reinfection. Real-component spacers had shorter hospital stays (3.3 ± 1.7 vs 5.4 ± 4.9 days; P < .01) and operative times during Stage 2 (162.2 ± 47.5 vs 188.0 ± 66.0 minutes; P = .01). CONCLUSION/CONCLUSIONS:Real-component spacers had improved ROM after Stage 1 and lower blood loss, shorter operative time, and shorter hospital stays after Stage 2 compared to all-cement articulating spacers. The 2 spacer constructs had the same ultimate change in ROM and no difference in reinfection rates, indicating that both articulating spacer types may be safe and effective options for 2-stage revision TKA. LEVEL OF EVIDENCE/METHODS:III, retrospective observational analysis.

BACKGROUND:The purpose of this study is to describe a Level 1 Trauma Center's orthopedic response to the COVID-19 pandemic, and to compare outcomes of acute fracture patients pre-COVID versus during the COVID-19 pandemic. METHODS:All inpatient fracture cases performed over a 5-month period were identified and retrospective chart review performed. Patients were divided into pre- and COVID-era groups based on when surgery was performed relative to March 16, 2020 (the date elective operations were ceased), and groups were statistically compared. Patients with a COVID test result were further sub-divided into COVID negative and positive groups, and statistically compared. Statistical analysis was performed using independent t-test for continuous variables and chi-square analysis for categorical variables. RESULTS:One hundred and nineteen patients were identified, 38% females with average age of 58 years. Average length of stay was 7 days with average time from injury to surgery of 3 days and average time from admission to surgery of 1.3 days. Overall in-hospital complication rate was 29.4%, and 30-day mortality and readmission rates were 2.5% and 5%, respectively. Sixty-nine patients comprised the pre-COVID group, and 50 in the COVID-era group. There was no significant difference with respect to length of stay, time from injury to surgery, time from admission to surgery, need for post-operative ICU stay, in-hospital complication rate, 30-day mortality rate and 30-day readmission rate. Thirty-four patients had COVID testing, with 24 negative and 10 positive. COVID-positive patients had longer time from injury to surgery (8.5 days vs. 2 days, p = 0.003) and longer time from admission to surgery (2.7 days vs. 1.2 days, p = 0.034). While more COVID-positive patients required ICU admission post-operatively (60% vs. 21%, p = 0.036), there was no difference in overall complication rate. CONCLUSIONS:Orthopedic care of acute fracture patients was not affected by a global pandemic. The response of our Level 1 Trauma Center's orthopedic department can guide other hospitals if and when new surges in COVID cases arise, in order to prevent compromising appropriate orthopedic care. LEVEL OF EVIDENCE/METHODS:Prognostic III.

INTRODUCTION/BACKGROUND:There is debate regarding whether the use of computer-assisted technology, such as navigation and robotics, has any benefit on outcomes or patient-reported outcome measures (PROMs) following total knee arthroplasty (TKA). This study aims to report on the association between intraoperative use of technology and outcomes in patients who underwent primary TKA. METHODS:We retrospectively reviewed 7096 patients who underwent primary TKA from 2016-2020. Patients were stratified depending on the technology utilized: navigation, robotics, or no technology. Patient demographics, clinical data, Forgotten Joint Score-12 (FJS), and Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) were collected at various time points up to 1-year follow-up. Demographic differences were assessed with chi-square and ANOVA. Clinical data and PROMs were compared using univariate ANCOVA, controlling for demographic differences. RESULTS:A total of 287(4%) navigation, 367(5%) robotics, and 6442(91%) manual cases were included. Surgical-time significantly differed between the three groups (113.33 vs 117.44 vs 102.11; P < .001). Discharge disposition significantly differed between the three groups (P < .001), with more manual TKA patients discharged to a skilled nursing facility (12% vs 8% vs 15%; P < .001) than those who had technology utilized. FJS scores did not statistically differ at three-months (P = .067) and one-year (P = .221). We found significant statistical differences in three-month KOOS, JR scores (59.48 vs 60.10 vs 63.64; P = .001); however, one-year scores did not statistically differ between all groups (P = .320). CONCLUSION/CONCLUSIONS:This study demonstrates shorter operative-time in cases with no utilization of technology and clinically similar PROMs associated with TKAs performed between all modalities. While the use of technology may aid surgeons, it has not currently translated to better short-term outcomes. LEVEL III EVIDENCE/UNASSIGNED:Retrospective Cohort.

BACKGROUND:Vancomycin powder and dilute povidone-iodine lavage (VIP) was introduced to reduce the incidence of periprosthetic joint infection (PJI) in high-risk total knee arthroplasty (TKA) patients. We hypothesize that VIP can reduce the incidence of early PJI in all primary TKA patients, regardless of preoperative risk. METHODS:An infection database of primary TKAs performed before a VIP protocol was implemented (January 2012-December 2013), during a time when only high-risk TKAs received VIP (January 2014-December 2015), and when all TKAs received VIP (January 2016-September 2019) at an urban, university-affiliated, not-for-profit orthopedic hospital was retrospectively reviewed to identify patients with PJI. Criteria used for diagnosis of PJI were the National Healthcare Safety Network and Musculoskeletal Infection Society guidelines. RESULTS:VIP reduced early primary TKA PJI incidence in both the high-risk and all-risk cohorts compared with the pre-VIP cohort by 44.6% and 56.4%, respectively (1.01% vs 0.56% vs 0.44%, P = .0088). In addition, after introducing VIP to all-risk TKA patients, compared with high-risk TKA patients, the relative risk of PJI dropped an additional 21.4%, but this finding did not reach statistical significance (0.56% vs 0.44%, P = .4212). There were no demographic differences between the 3 VIP PJI cohorts. CONCLUSION/CONCLUSIONS:VIP is associated with a reduced early PJI incidence after primary TKA, regardless of preoperative risk. With the literature supporting its safety and cost-effectiveness, VIP is a value-based intervention, but given the nature of this historical cohort study, a multicenter randomized controlled trial is underway to definitively confirm its efficacy.

PURPOSE/OBJECTIVE:Surgeons must rely on manufacturers to provide an appropriate distribution of total knee arthroplasty (TKA) sizes. There is a lack of literature regarding current appropriateness of tibial sizing schemes according to sex. As such, a study was devised assessing the adequacy of off-the-shelf tibial component size availability according to sex. METHODS:A search was conducted to identify all primary TKAs between July 2012 and June 2019 performed using a single implant. Baseline patient characteristics were collected (age, weight, height, BMI, and race). Two cohorts were created according to patient sex. Tibial sizes for each cohort were collected. Tibial component bar graph and histogram were created according to component sizes. Skewness and kurtosis were calculated for each distribution. Overhang was noted and measured radiographically. RESULTS:A total of 864 patients were identified, 38.7% males and 61.3% females. Most patients were Caucasian, and BMI was similar between cohorts. Tibial size distribution for males was as follows: 0.3% C, 4.8% D, 16.5% E, 40.1% F, 31.4% G, 6.9% H. Tibial size distribution for females was as follows: 30.8% C, 42.8% D, 23.0% E, 2.6% F, 0.8% G, 0.0% H. Histograms and normal curves demonstrated a fairly symmetric distribution of sizes for males (skewness = - 0.31, kurtosis = - 0.03). The distribution for females was positively skewed (skewness = 0.57, kurtosis = 0.12). Overall, overhang was noted in 16.6% of all size C tibias. CONCLUSIONS:The results of this study highlight an implant-specific discrepancy in size availability affecting female patients which could result in inferior outcomes. The authors urge manufacturers to critically assess current implant size distribution availability to ensure both genders are adequately, and equally represented. LEVEL OF EVIDENCE/METHODS:IV.

Patellar position and alignment may be measured on routine axial radiographs by various techniques; however, the agreement and reliability of such measurements with a resurfaced patella remain unknown. This study evaluated the range and reliability of lateral patellar tilt and lateral patellar displacement following total knee arthroplasty (TKA) with a resurfaced patella among three observers on 45° Merchant view in 139 TKAs. Intraclass correlation coefficient (ICCs) were used to evaluate intraobserver agreement (IOA) and inter-rater reliability (IRR). IRR was high between each of the observers for lateral patellar tilt (ICC = 0.8) and lateral patellar displacement (ICC = 0.87). IOA was also high upon repeat measurement for the same observer for lateral patellar tilt (ICC ≥ 0.90) and lateral patellar displacement (ICC ≥ 0.86). Therefore, lateral patellar tilt and lateral patellar displacement are reproducible measurements of patellar position on a Merchant axial radiograph following a well-functioning TKA with a resurfaced patella.

The optimal approach for total hip arthroplasty (THA) remains hotly debated. While wound complications following the direct anterior approach are higher than with other approaches, the organism profile of periprosthetic joint infections (PJIs) by approach remains unknown. Our goal was to compare the organism profiles of PJIs following direct anterior and non-anterior THA.

Background/UNASSIGNED:Total hip arthroplasty (THA) is an effective operation for patients with hip osteoarthritis; however, patients with hip dysplasia present a particular challenge. Our novel study examined the effect of robot-assisted THA in patients with hip dysplasia. Methods/UNASSIGNED:We retrospectively reviewed patients with developmental dysplasia of the hip undergoing primary THA using robotic arm assistance at 2 institutions from January 2010 to January 2017. Patients undergoing revision arthroplasty were excluded. Preoperatively, all patients underwent a computed tomography scan so that 3-dimensional templating could be performed. Hip range of motion (ROM) and clinical leg length discrepancy were recorded preoperatively. Two independent observers calculated Crowe and Hartofilakidis grades for each operative hip. At the final follow-up, hip ROM, postoperative complications, and modified Harris Hip scores were obtained. Results/UNASSIGNED:< .0002). There were no complications during the short-term interim follow-up (mean: 3.1 years). Conclusions/UNASSIGNED:Robot-assisted THA can be a useful method to ensure adequate component positioning and excellent outcomes in patients with hip dysplasia. Level of Evidence/UNASSIGNED:Level III, Retrospective.

OBJECTIVES:(1) To demonstrate how a risk assessment tool modified to account for the COVID-19 virus during the current global pandemic is able to provide risk assessment for low-energy geriatric hip fracture patients. (2) To provide a treatment algorithm for care of COVID-19 positive/suspected hip fractures patients that accounts for their increased risk of morbidity and mortality. SETTING:One academic medical center including 4 Level 1 trauma centers, 1 university-based tertiary care referral hospital, and 1 orthopaedic specialty hospital. PATIENTS/PARTICIPANTS:One thousand two hundred seventy-eight patients treated for hip fractures between October 2014 and April 2020, including 136 patients treated during the COVID-19 pandemic between February 1, 2020 and April 15, 2020. INTERVENTION:The Score for Trauma Triage in the Geriatric and Middle-Aged ORIGINAL (STTGMAORIGINAL) score was modified by adding COVID-19 virus as a risk factor for mortality to create the STTGMACOVID score. Patients were stratified into quartiles to demonstrate differences in risk distribution between the scores. MAIN OUTCOME MEASUREMENTS:Inpatient and 30-day mortality, major, and minor complications. RESULTS:Both STTGMA score and COVID-19 positive/suspected status are independent predictors of inpatient mortality, confirming their use in risk assessment models for geriatric hip fracture patients. Compared with STTGMAORIGINAL, where COVID-19 patients are haphazardly distributed among the risk groups and COVID-19 inpatient and 30 days mortalities comprise 50% deaths in the minimal-risk and low-risk cohorts, the STTGMACOVID tool is able to triage 100% of COVID-19 patients and 100% of COVID-19 inpatient and 30 days mortalities into the highest risk quartile, where it was demonstrated that these patients have a 55% rate of pneumonia, a 35% rate of acute respiratory distress syndrome, a 22% rate of inpatient mortality, and a 35% rate of 30 days mortality. COVID-19 patients who are symptomatic on presentation to the emergency department and undergo surgical fixation have a 30% inpatient mortality rate compared with 12.5% for patients who are initially asymptomatic but later develop symptoms. CONCLUSION:The STTGMA tool can be modified for specific disease processes, in this case to account for the COVID-19 virus and provide a robust risk stratification tool that accounts for a heretofore unknown risk factor. COVID-19 positive/suspected status portends a poor outcome in this susceptible trauma population and should be included in risk assessment models. These patients should be considered a high risk for perioperative morbidity and mortality. Patients with COVID-19 symptoms on presentation should have surgery deferred until symptoms improve or resolve and should be reassessed for surgical treatment versus definitive nonoperative treatment with palliative care and/or hospice care. LEVEL OF EVIDENCE:Prognostic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

Selective supplementation of acetabular component fixation with a screw during primary total hip arthroplasty (THA) assumes that the surgeon can detect when an acetabular component needs additional stability. In contrast, nonselective screw users do not alter their practice based on their interpretation of stability and either use screws all or none of the time. We aimed to determine the effect of selective screw use on aseptic acetabular component loosening. We retrospectively reviewed aseptic failures of acetabular components after primaty THA. We compared the survivorship of selective and nonselective supplementation of acetabular fixation with respect to time to revision, obesity, and screw use. Selective screw use (n = 16) was associated with earlier acetabular component aseptic loosening (median: 1.9 years; interquartile range [IQR]: 1.1-5.0) compared to nonselective screw use (n = 22; median: 5.6 years; IQR: 2.0-15.3; P = .010). Selective screw use was independently associated with earlier revision after adjusting for patient obesity. Obesity was associated with selective screw use in 50% of the cases vs 14% of nonselective cases (odds ratio: 6.3; confidence interval: 1.2-25.2; P = .028), possibly reflecting the increased difficulty in achieving acetabular component stability in this and other settings with compromised bone. Surgeons should carefully assess component stability at time of primary THA. If the acetabulum is not stable, the addition of screws alone may not be sufficient for acetabular component stability.