The effect of reduced bone mineral density on elective total hip arthroplasty outcomes.

INTRODUCTION: Reduced bone mineral density (BMD) and disruption of normal bony architecture are the characteristics of osteopenia and osteoporosis and in patients undergoing total hip arthroplasty (THA) may cause failure of trabecular ingrowth. The purpose of this study is to evaluate the impact of reduced BMD on outcomes following primary elective THA. METHODS: A retrospective chart review of 650 elective THAs with a DEXA scan in their electronic health record (EHR) from 2011 to 2020 was conducted at an urban, academic center and a regional, health center. Patients were separated into three cohorts based on their t-score and the World Health Organizations definitions: normal (t-score ≥ - 1), osteopenia (t-score < - 1.0 and > - 2.5), and osteoporosis (t-score ≤ - 2.5). Demographic and outcome data were assessed. Subsidence was assessed for patients with non-cemented THAs. Regression models were used to account for demographic differences. RESULTS: 650 elective THAs, of which only 11 were cemented, were included in the study. Patients with osteopenia and osteoporosis were significantly older than those without (p = 0.002 and p < 0.0001, respectively) and had a lower BMI (p < 0.0001 and p < 0.0001, respectively). PFx was significantly greater in patients with osteoporosis when compared to those with normal BMD (6.5% vs. 1.0%; p = 0.04). No such difference was found between osteoporotic and osteopenic patients. The revision rate was significantly higher for osteoporotic patients than osteopenic patients (7.5% vs. 1.5%; p = 0.04). No such difference was found between the other comparison groups. CONCLUSION: Patients with osteoporosis were older with reduced BMI and had increased PFx after non-cemented elective THA. Understanding this can help surgeons formulate an appropriate preoperative plan for the treatment of patients with osteoporotic bone undergoing elective THA.

The role of the lower extremity functional scale in predicting surgical outcomes for total joint arthroplasty patients.

BACKGROUND: The purpose of this study was to evaluate the relationship between lower extremity functional scale (LEFS) scores with postoperative functional outcomes for total joint arthroplasty (TJA) patients and to investigate the utility of this tool to create an individualized plan of care perioperatively. METHODS: Patients undergoing primary TJA at a single institution from 2016 to 2019 was retrospectively reviewed by a univariate analysis in terms of patient characteristics and outcomes across LEFS quartiles. Multivariate regression models were constructed to evaluate the association between the LEFS quartile and outcomes after controlling for confounding factors. RESULTS: A total of 1389 patients were included. All patients had a documented LEFS pre- and postoperatively with the last value documented at least 60 days to a maximum of 1 year after surgery. The following cutoffs for LEFS quartiles were observed: quartile 1 preoperative LEFS ≤27, quartile 2 ranges from 28 to 35, quartile 3 ranges from 36 to 43, and quartile 4 ≥ 44. Patients with a higher comorbidity burden and ASA score were more likely to have a lower LEFS. Higher levels of preoperative function were significantly associated with shorter LOS and higher rates of same day discharge, independent ambulation, mobility and activity scores, and rates of discharge home. CONCLUSION: These findings suggest that LEFS is a useful tool for aiding clinical resource allocation decisions, and incorporation of the measure into existing predictive models may improve their accuracy.

Risk factors for progression to total knee arthroplasty within two years of presentation for knee osteoarthritis.

INTRODUCTION: Knee osteoarthritis (OA) is a leading cause of disability and functional limitations in aging adults. Total knee arthroplasty (TKA) is the gold standard treatment of this condition. The purpose of this study is to evaluate which patient characteristics are associated with proceeding to TKA. METHODS: Retrospective review of patients with knee osteoarthritis at a single institution was conducted. Demographic, radiographic and clinical patient characteristics were analyzed. The primary outcome measure was whether patients underwent TKA over the study time-period. Univariate comparisons between patients not undergoing surgery and those undergoing TKA were performed. Multivariate logistic regression was performed to evaluate risk factors for undergoing TKA. RESULTS: Two hundred seven patients were included in the study. One hundred eighty seven patients (90.3%) did not undergo surgery, while 20 (9.7%) underwent TKA. No statistically significant differences in demographics were observed between patients who underwent TKA and those who did not. On multivariate analysis, patients with Kellgren Lawrence grade 4 OA (OR: 20.793, p = 0.009) and varus alignment (OR: 13.044, p = 0.040) were at significantly increased risk of undergoing TKA. Using only these two variables, the area under the curve for predicting which patients would undergo TKA was 0.846, indicating excellent discrimination. CONCLUSION: In patients diagnosed with knee OA, Kellgren Lawrence grade 4 classification and varus knee alignment are significant risk factors for undergoing TKA, and are associated with a decreased time from initial presentation to surgery. These findings may be used to counsel patients, aid triage decisions, and inform the development of future predictive models.

Preoperative Predictors of Same-Day Discharge After Total Knee Arthroplasty.

BACKGROUND: In January 2020, The Centers for Medicare and Medicaid Services approved total knee arthroplasty (TKA) to be performed in ambulatory surgery centers (ASCs). This study aims to develop a predictive model for targeting appropriate patients for ASC-based TKA. METHODS: A retrospective review of 2266 patients (205 same-day discharge [SDD; 9.0%] and 2061 one-day length of stay [91.0%]) undergoing TKA at a regional medical center between July 2016 and September 2020 was conducted. Multiple logistic regression was used to evaluate predictors of SDD, as these patients represent those most likely to safely undergo TKA in an ASC. RESULTS: Controlling for other demographics and comorbidities, patients with the following characteristics were at reduced odds of SDD: increased age (odds ratio [OR] = 0.935, P < .001), body mass index ≥35 (OR = 0.491, P = .002), female (OR = 0.535, P < .001), nonwhite race (OR = 0.456, P = .003), primary hypertension (OR = 0.710, P = .032), ≥3 comorbidities (OR = 0.507, P = .002), American Society of Anesthesiologists score ≥3 (OR = 0.378, P < .001). The model was deemed to be of adequate fit using the Hosmer and Lemeshow test (χ2 = 12.437, P = .112), and the area under the curve was found to be 0.773 indicating acceptable discrimination. CONCLUSION: For patients undergoing primary TKA, increased age, body mass index ≥35, female gender, nonwhite race, primary hypertension, ≥3 comorbidities, and American Society of Anesthesiologists score ≥3 decrease the likelihood of SDD. A predictive model based on readily available patient presentation and comorbidity characteristics may aid surgeons in identifying patients that are candidates for SDD or ASC-based TKA.

The Utility of Frozen Section Histology in Diagnosing Periprosthetic Joint Infection in Revision Total Joint Arthroplasty.

BACKGROUND: Surgeons utilize a combination of preoperative tests and intraoperative findings to diagnose periprosthetic joint infection (PJI); however, there is currently no reliable diagnostic marker that can be used in isolation. The purpose of our study is to evaluate the utility of frozen section histology in diagnosis of PJI. METHODS: Retrospective analysis of 614 patients undergoing revision total joint arthroplasty with frozen section histology from a single institution was performed. Discriminatory value of frozen section histology was assessed using univariate analysis and evaluation of area under the curve (AUC) of a receiver operating characteristic curve comparing frozen section histology results to the 2018 International Consensus Meeting (ICM) PJI criteria modified to exclude the histology component. RESULTS: The sensitivity of the frozen section histology was 53.6% and the specificity was 95.2%. There was 99.2% concordance between the permanent section and frozen section results. The receiver operating characteristic curve for frozen section yielded an AUC of 0.744 (95% confidence interval 0.627-0.860) and the modified ICM score yielded an AUC of 0.912 (95% confidence interval 0.836-0.988) when compared to the full score. The addition of frozen section histology changed the decision to infected in 20% of "inconclusive" cases but less than 1% of total cases. CONCLUSION: In comparison to the modified ICM criteria, intraoperative frozen section histology has poor sensitivity, strong specificity, and acceptable overall discrimination for diagnosing PJI. This test appears to be of particular value for patients deemed "inconclusive" for infection using the remaining ICM criteria.

Impact of Dexamethasone on Length of Stay and Early Pain Control in Direct Anterior Approach Total Hip Arthroplasty With Neuraxial Anesthesia.

BACKGROUND: Dexamethasone has been shown to reduce postoperative pain and opioid consumption for total joint arthroplasty patients; however, its impact on patients who received neuraxial anesthesia (NA) is not well described. We examined the impact of perioperative dexamethasone on outcomes for patients undergoing direct anterior approach total hip arthroplasty (THA) under NA. METHODS: A retrospective review was conducted for 376 THA patients from a single institution. Univariate analysis was used to compare postoperative outcomes for 164 THA patients receiving dexamethasone compared to 212 who did not receive dexamethasone. RESULTS: No differences in age, gender, body mass index, or American Society of Anesthesiologists (ASA) Score were observed between the groups. Patients receiving perioperative dexamethasone reported statistically significantly lower postanesthesia care unit (PACU) pain numeric rating scale (Dexamethasone 1.6 vs No dexamethasone 2.3, P = .014) and received lower PACU morphine milligram equivalents (MME) (Dexamethasone 8.57 vs No dexamethasone 11.44, P < .001). Patients receiving dexamethasone had significantly shorter LOS (Dexamethasone 29.40 vs No dexamethasone 35.26 hrs., P < .001). CONCLUSION: Perioperative dexamethasone is associated with decreased postoperative pain and narcotic consumption, and shorter length of stay for patients undergoing primary direct anterior approach THA with NA.

General vs Neuraxial Anesthesia in Direct Anterior Approach Total Hip Arthroplasty: Effect on Length of Stay and Early Pain Control.

BACKGROUND: Recent literature has suggested some benefits for neuraxial anesthesia (NA) as an alternative for general anesthesia (GA) for primary total hip arthroplasty patients. We examined the impact of NA vs GA on outcomes for patients undergoing direct anterior (DA) approach total hip arthroplasty (THA) in an institution with established rapid recovery protocols. METHODS: A retrospective review was conducted for 500 consecutive THA patients from a single institution. Univariate analysis and multivariate linear regression were used to compare outcomes for THA patients receiving NA and GA. RESULTS: There was a significant difference in length of stay with NA patients having a shorter length of stay (NA 32.7 hours vs GA 38.1 hours, P = .003). Patients receiving NA had significantly lower PACU morphine milligram equivalents (MME) (NA 10.2 MME vs GA 15.6 MME, P < .001) and reported a lower score on the PACU pain numeric rating scale (NA 2.1 vs GA 3.7, P < .001). CONCLUSION: Neuraxial anesthesia is associated with decreased LOS, decreased PACU MME, and a lower PACU pain score for patients undergoing primary DA THA. These trends remained consistent when controlling for age, gender, BMI, and ASA.