Faculty Bibliography

INTRODUCTION/BACKGROUND:Although technology-assisted total hip arthroplasty (TA-THA) may improve implant positioning, it remains unknown whether TA-THA confers improved clinical outcomes. We sought to examine national TA-THA utilization trends and compare clinical outcomes between TA-THA and unassisted THA (U-THA). METHODS:Patients who underwent primary, elective THA from 2010 to 2018 were identified using the American College of Surgeons National Surgical Quality Improvement Program database. Demographic, perioperative, and 30-day outcomes were queried and collected. Patients were stratified based on whether they underwent TA-THA, which included computer navigation or robotics, and U-THA. Propensity score matching paired patients undergoing TA-THA or U-THA on a 1:1 basis. RESULTS:Of the 238,755 THA patients, 3,149 cases (1.3%) were done using TA-THA. Comparing the unmatched TA-THA and U-THA groups, race distribution (P < 0.001) and baseline functional status (P < 0.001) differed. Propensity score matching yielded 2,335 TA-THA and U-THA pairs. Perioperatively, the TA-THA cohort had longer mean surgical times (101.0 ± 34.0 versus 91.9 ± 38.8 minutes, P < 0.001), but lower transfusion rates (5.7% versus 7.8%, P = 0.005). As compared with the U-THA group, the TA-THA group had a shorter mean hospital length of stay (2.0 ± 1.1 versus 2.5 ± 2.0 days, P < 0.001) and a higher proportion of patients discharged home (85.8% versus 75.7%, P < 0.001). Notably, the TA-THA cohort had higher readmission rates (3.8% versus 2.4%, P < 0.001). Major complication and revision surgery rates did not markedly differ between groups. DISCUSSION/CONCLUSIONS:TA-THA utilization rates remain low among orthopaedic surgeons. As compared with U-THA, TA-THA yield mixed perioperative and 30-day outcomes. Surgeons must consider the clinical benefits and drawbacks of TA-THA when determining the proper surgical technique and technology for each patient. Clinical trials assessing long-term functional and clinical outcomes between U-THA and TA-THA are required to further elucidate the utility of assistive technologies in THA. LEVEL III EVIDENCE/UNASSIGNED:Retrospective Cohort Study.

INTRODUCTION:Obstructive sleep apnea (OSA) is a known risk factor for venous thromboembolism (VTE), defined as pulmonary embolism (PE) or deep vein thrombosis (DVT); however, little is known about its effect on VTE rates after total joint arthroplasty (TJA). This study sought to determine whether patients with OSA who undergo TJA are at greater risk for developing VTE versus those without OSA. METHODS:A retrospective analysis was conducted on 12,963 consecutive primary TJA patients at a single institution from 2016 to 2019. Patient demographic data were collected through query of the electronic medical record, and patients with a previous history of OSA and VTE within a 90-day postoperative period were captured using the International Classification of Disease, 10th revision diagnosis and procedure codes. RESULTS:Nine hundred thirty-five patients with OSA were identified. PE (0.6% versus 0.24%, P = 0.023) and DVT (0.1% versus 0.04%, P = 0.37) rates were greater for patients with OSA. A multivariate logistic regression revealed that patients with OSA had a higher odds of PE (odds ratio [OR] 3.821, P = 0.023), but not DVT (OR 1.971, P = 0.563) when accounting for significant demographic differences. Female sex and total knee arthroplasty were also associated with a higher odds of PE (OR 3.453 for sex, P = 0.05; OR 3.243 for surgery type, P = 0.041), but not DVT (OR 2.042 for sex, P = 0.534; OR 1.941 for surgery type, P = 0.565). CONCLUSION:Female patients with OSA may be at greater risk for VTE, specifically PE, after total knee arthroplasty. More attention toward screening procedures, perioperative monitoring protocols, and VTE prophylaxis may be warranted in populations at risk.

Venous thromboembolism (VTE) events are rare, but serious complications of total joint replacement affect patients and health care systems due to the morbidity, mortality, and associated cost of its complications. There is currently no established universal standard of care for prophylaxis against VTE in patients undergoing revision total knee arthroplasty (rTKA). The aim of this study was to determine whether a protocol of 81-mg aspirin (ASA) bis in die (BID) is safe and/or sufficient in preventing VTE in patients undergoing rTKAs versus 325-mg ASA BID. In 2017, our institution adopted a new protocol for VTE prophylaxis for arthroplasty patients. Patients initially received 325-mg ASA BID for 1 month and then changed to a lower dose of 81-mg BID. A retrospective review from 2011 to 2019 was conducted identifying 1,438 consecutive rTKA patients and 90-day postoperative outcomes including VTE, gastrointestinal, and wound bleeding complications, acute periprosthetic joint infection, and mortality. In the 74 months prior to protocol implementation, 1,003 rTKAs were performed and nine VTE cases were diagnosed (0.90%). After 26 months of the protocol change, 435 rTKAs were performed with one VTE case identified (0.23%). There was no significant difference in rates or odds in postoperative pulmonary embolism (PE; p = 0.27), DVT (p = 0.35), and total VTE rates (p = 0.16) among patients using either protocol. There were also no differences in bleeding complications (p = 0.15) or infection rate (p = 0.36). No mortalities were observed. In the conclusion, 81-mg ASA BID is noninferior to 325-mg ASA BID in maintaining low rates of VTE and may be safe for use in patients undergoing rTKA.

PURPOSE/OBJECTIVE:Back pain may both decrease patient satisfaction after TKA and confound outcome assessment in satisfied patients. Our primary objective was to determine whether preoperative back pain is associated with differences in postoperative patient-reported outcome measures (PROMs). METHODS:We retrospectively reviewed 234 primary TKA patients who completed PROMs preoperatively and 12 weeks postoperatively, which included a back pain questionnaire, the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and the Forgotten Joint Score-12 (FJS-12). Cohorts were defined based on the severity of preoperative back pain (none, mild, moderate and severe) and compared. Demographics were compared using ANOVA and Chi-square analysis. Univariate ANCOVA analysis was utilized to compare PROMs while accounting for significant demographic differences. RESULTS:Both preoperative KOOS JR scores (none: 47.90, mild: 47.61, moderate: 44.61 and severe: 38.70; p = 0.013) and 12-week postoperative KOOS JR scores (none: 61.24, mild: 64.94, moderate: 57.48 and severe: 57.01; p = 0.012) had a statistically significant inverse relationship with regard to the intensity of preoperative back pain. Although FJS-12 scores at the 12-week postoperative period trended lower with increasing levels of preoperative back pain (p = 0.362), it did not reach statistical significance. Patients who reported severe back pain preoperatively achieved the largest delta improvement from baseline compared to those with lesser pain intensity (p = 0.003). Patients who had a 2-grade improvement in their back pain achieved significantly higher KOOS JR scores 12 weeks postoperatively compared to patients with either 1-grade or no improvement (63.53 vs. 55.98; p = 0.042). Both preoperative (47.99 vs. 41.11; p = 0.003) and 12-week postoperative (64.06 vs. 55.73; p < 0.001) KOOS JR scores were statistically higher for those who reported mild or no back pain pre-and postoperatively than those who reported moderate or severe back pain pre-and postoperatively. CONCLUSION/CONCLUSIONS:Knee pain and back pain both exert negative effects on outcome instruments designed to measure pain and function. Although mean improvement from pre- to postoperative KOOS JR scores for patients with severe pre-existing back pain was higher than their counterparts, this statistical difference is likely not clinically significant. This implies that all patients may experience similar benefits from TKA despite the presence or absence of back pain. Attempts to measure TKA outcomes using PROMs should seek to control for lumbago and other sources of body pain. Level of Evidence IIIRetrospective Cohort Study.

INTRODUCTION/BACKGROUND:Preoperative anemia (POA) is a significant predictor for adverse outcomes in primary total hip arthroplasty (THA). Current literature has studied POA stratified by severity. This study aims to find a threshold preoperative hemoglobin (Hb) value for increased risk of adverse outcomes in THA. METHODS:This was a retrospective analysis of primary THA patients with preoperative Hb values from 2014-2021 from an academic orthopedic specialty hospital. Demographics, surgical data, and post-operative outcomes were collected. Patients without preoperative Hb values within the electronic health record (EHR) system or values acquired >30 days preoperatively were excluded. Patients were grouped based on POA severity using WHO criteria. Secondary analysis using discrete preoperative Hb values was performed. P-values were calculated using ANOVA/Kruskal-Wallis and chi-square/Fisher's exact testing with p<0.05 considered significant. RESULTS:A total of 1,347 patients were included, 771(57.2%) patients with POA and 576(42.8%) with normal pre-operative Hb. In the POA group, 292(37.9%) were mild, 445(57.7%) moderate, and 34(4.4%) severe. Increased length of stay (LOS) was seen in moderate (3.9+4.3vs.2.4+2.1,p<0.001) and severe (5.0+3.4vs.2.4+2.1,p<0.0001) groups compared to control. The severe group had higher 90-day readmission and revision rates compared to control. Analysis by discrete Hb values showed increased LOS in Hb values <11g/dL and a greater proportion of patients with Hb values <12g/dL were discharged to skilled nursing facilities. CONCLUSION/CONCLUSIONS:Patients with preoperative Hb <12g/dL should be assessed for other risk factors that may predispose them to post-operative complications. Further investigation is warranted to develop more robust perioperative management strategies for POA patients undergoing THA.

INTRODUCTION/BACKGROUND:Despite increased efforts towards patient optimization, some patients have undocumented conditions that can affect costs and quality metrics for institutions and physicians. This study evaluates the effect of documented and undocumented psychiatric conditions on LOS and discharge disposition following total hip arthroplasty (THA). METHODS:A retrospective review of all primary THAs from 2015-2020 at a high-volume academic orthopedic specialty hospital was conducted. Patients were separated into three cohorts: patients with a documented psychiatric diagnosis (+Dx), patients without a documented psychiatric diagnosis but with an actively prescribed psychiatric medication (-Dx), and patients without a psychiatric diagnosis or medication (control). Patient demographics, LOS, and discharge disposition were assessed. RESULTS:A total of 5,309 patients were included; 3,048 patients had no recorded psychiatric medications (control); 2,261 patients took at least one psychiatric medication, of which 1,513 (65.9%) and 748 (34.1%) patients were put in the -Dx and +Dx cohorts, respectively. ASA Class differed between groups (<0.001). The -Dx and +Dx groups had increased LOS (3.15±2.37 (75.6±56.9) and 3.12±2.27 (74.9±54.5) versus 2.42±1.70 (57.6±40.8) days (hours), p<0.001) and were more likely to be discharged to a secondary facility (23.0% and 21.7% versus 13.8%, p<0.001) than the control group. Outcomes did not significantly differ between the -Dx and +Dx cohorts. CONCLUSION/CONCLUSIONS:Most THA patients' psychiatric diagnoses were not documented. The presence of psychiatric medications was associated with longer LOS and a greater likelihood of discharge to secondary facilities. This has implications for both cost and quality metrics. Review of medications can help identify and optimize these patients before surgery.

AIMS/OBJECTIVE:The Forgotten Joint Score-12 (FJS-12) is a validated patient-reported outcome measure (PROM) tool designed to assess artificial prosthesis awareness during daily activities following total hip arthroplasty (THA). The patient-acceptable symptom state (PASS) is the minimum cut-off value that corresponds to a patient's satisfactory state-of-health. Despite the validity and reliability of the FJS-12 having been previously demonstrated, the PASS has yet to be clearly defined. This study aims to define the PASS of the FJS-12 following primary THA. METHODS:We retrospectively reviewed all patients who underwent primary elective THA from 2019 to 2020, and answered both the FJS-12 and the Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS, JR) questionnaires one-year postoperatively. HOOS, JR score was used as the anchor to estimate the PASS of FJS-12. Two statistical methods were employed: the receiver operating characteristic (ROC) curve point, which maximized the Youden index; and 75th percentile of the cumulative percentage curve of patients who had the HOOS, JR score difference larger than the cut-off value. RESULTS:This study included 780 patients. The mean one-year FJS-12 score was 65.42 (SD 28.59). The mean one-year HOOS, JR score was 82.70 (SD 16.57). A high positive correlation between FJS-12 and HOOS, JR was found (r = 0.74; p<0.001), making the HOOS, JR a valid external anchor. The threshold score of the FJS-12 that maximized the sensitivity and specificity for detecting a PASS was 66.68 (area under the curve = 0.8). The cut-off score value computed with the 75th percentile approach was 92.20. CONCLUSION/CONCLUSIONS: 2022;3(4):307-313.

BACKGROUND:While technology-assisted total knee arthroplasty (TA-TKA) improves implant positioning, whether it confers improved clinical outcomes remains inconclusive. We sought to examine national TA-TKA utilization trends and to compare outcomes between TA-TKA and unassisted TKA (U-TKA). METHODS:Patients who underwent primary, elective TKA from 2010 to 2018 were identified using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Demographic, perioperative, and 30-day outcomes were collected. Patients were stratified on the basis of whether they underwent TA-TKA, which included computer navigation and robotics, or U-TKA. The proportion of patients undergoing TKA using TA-TKA was calculated. One-to-one propensity-score matching paired patients undergoing TA-TKA or U-TKA. Independent samples t-tests and Mann-Whitney U tests were used to compare continuous variables, and chi-squared tests were used to compare categorical variables. RESULTS:Of the 402,284 TKA patients, 10,429 (2.6%) cases were performed using TA-TKA. Comparing the unmatched TA-TKA and U-TKA groups, race (p < 0.001), smoking status (p = 0.050), baseline functional status (p < 0.001), and body mass index (BMI) (p < 0.001) significantly differed. Propensity-score matching yielded 8633 TA-TKA and U-TKA pairs. The TA-TKA cohort had shorter hospital length of stay (LOS) (2.7 ± 2.5 versus 2.8 ± 1.9 days, p = 0.017) but similar operative times (92.4 ± 33.4 versus 92.6 ± 39.8 min, p = 0.670). Compared with the U-TKA group, the TA-TKA group had lower major complication (7.6% versus 9.4%, p < 0.001) and transfusion (3.9% versus 5.1%, p < 0.001) rates and higher rates of discharge to home (73.9% versus 70.4%, p < 0.001). Reoperation and readmission rates did not significantly differ between groups. CONCLUSIONS:TA-TKA utilization remains low among orthopedic surgeons. Compared with U-TKA, TA-TKA yielded improved perioperative and 30-day outcomes. Nonetheless, surgeons must consider the benefits and drawbacks of TA-TKA when determining the proper surgical technique and technology for each patient. LEVEL III EVIDENCE/METHODS:Retrospective cohort study.

BACKGROUND:Obesity is a recognized risk factor for severe knee osteoarthritis. However, it remains unclear how obesity prevalence trends in the current population undergoing total knee arthroplasty (TKA) compare with those seen in individuals not undergoing this procedure. In this study, we assessed the yearly trends in body mass index (BMI) and obesity rates between patients who have undergone primary TKA and those in the general population. METHODS:We retrospectively reviewed all patients ≥18 years of age from January 2013 through December 2020 who underwent primary, elective TKA and those who had an annual routine physical examination at our institution within the same period. Baseline demographic characteristics were collected. The independent samples t test was used to compare means and the chi-square test was used to compare proportions between the 2 cohorts, and a linear regression was used to determine the significance of the yearly trends. RESULTS:A total of 11,333 patients who underwent primary TKA and 1,158,168 patients who underwent an annual physical examination were included in this study. After adjusting for age, we found the mean BMI for the TKA group to be significantly greater (p < 0.001) every year compared with the annual physicals group. The proportion of patients who were categorized into any obesity class (BMI, ≥30 kg/m2), Class-I obesity (BMI, 30 to 34.9 kg/m2), Class-II obesity (BMI, 35 to 39.9 kg/m2), and Class-III obesity (BMI, ≥40 kg/m2) was significantly higher for the TKA group each year compared with the annual physicals group. An analysis of trends over time showed a significantly increasing trend (p < 0.001) in BMI and obesity rates for the annual physicals group, but a stable trend for patients undergoing TKA. CONCLUSIONS:Patients who underwent TKA continued to have higher BMI than the general population, which showed a steady increase over time. Physicians need to continue in their efforts to educate patients on weight management and healthy lifestyles to potentially delay the need for a surgical procedure. LEVEL OF EVIDENCE/METHODS:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

INTRODUCTION/UNASSIGNED:Advanced age is considered a major risk factor for postoperative complications in total hip arthroplasty (THA). Consequently, older patients undergoing THA may require more detailed pre-procedural examinations and more healthcare resources postoperatively than younger patients. The purpose of this study was to compare discharge parameters and complication rates of THA in patients ⩾90 years old to those <90 years old. METHODS/UNASSIGNED:-tests. RESULTS/UNASSIGNED:= 1.000). CONCLUSIONS/UNASSIGNED:Although THA patients over 90 years of age had a longer LOS and differing discharge disposition, these patients had similar complications compared to their younger counterparts. Thus, our study supports similar efficacy of THA in patients 90 years and older relative to younger THA candidates.