Spinal fusion and total hip arthroplasty: why timing is important.

BACKGROUND: There is increasing debate among orthopaedic surgeons over the temporal relationship between lumbar spinal fusion (LSF) and total hip arthroplasty (THA) for patients with hip-spine syndrome. Few large studies have directly compared the results of patients who undergo LSF prior to THA (LSF-THA) to those who undergo LSF after THA (THA-LSF). The current study matched THA patients with a prior LSF to patients who underwent LSF after THA to assess: 90-day and 1-year (1) medical/surgical complications; and (2) revisions. METHODS: We queried a national, all-payer database to identify all patients undergoing THA between 2010 and 2018 (n = 716,084). The LSF-THA patients and THA-LSF patients were then matched 1:1 on age, sex, Charleson Comorbidity Index, and obesity. Medical/surgical complications and revisions at 90 days and 1 year were recorded. Categorical and continuous variables were analysed utilising t-tests and chi-square, respectively. RESULTS: LSF-THA patients experienced significantly more postoperative dislocations at 90 days and 1 year compared to THA-LSF patients (p = 0.048 and p < 0.001). There were a similar number of revisions performed for LSF-THA and THA-LSF patients at both 90 days and 1 year (p = 0.183 and p = 0.426). Furthermore, at 1 year, LSF-THA patients experienced more pneumonia (p = 0.005) and joint infection (p = 0.020). CONCLUSIONS: Prior LSF has been demonstrated to increase the risk of postoperative dislocation in patients undergoing THA. The results of the present study demonstrate increased dislocations with LSF-THA compared to THA-LSF. For "hip spine syndrome" patients requiring both LSF and THA, it may be more beneficial to undergo THA prior to LSF. Arthroplasty surgeons may wish to collaborate with spinal surgeons to ensure optimal outcomes for this group of patients.

Primary total hip arthroplasty complications and costs in liver transplant recipients: a matched analysis using a national database.

BACKGROUND: The number of liver transplant recipients (LTR) is worldwide increasing and, as the survival is improving as well, there is an increasing number of patients needing total hip arthroplasty (THA). There might be increased risks for this specific group of patients and due to their comorbidities costs might be higher too. Using a big national database outcome and cost of THA should be compared between liver transplant recipients and the general population. METHODS: The study was performed using a collection of Medicare, Medicaid, and private insurance claims. Length of stay (LOS), 30-day readmissions, complications rates up to 5 years, and 90-day total cost of care between liver transplant recipients and matched non-transplant patients should be compared. All primary THAs from 2010 to 2019 were identified. 513 patients with a liver transplant before their THA were matched to 10,759 patients without a history of solid organ transplant at a 1:20 ratio based on age, sex, Charlson Comorbidity Index, obesity, and diabetes status. RESULTS: LTR had a longer average LOS (4.2 vs. 3.4 days, p < 0.001). There was no difference in the thirty-day readmissions (5.7% vs. 4.1%, p = 0.117) and 90-day dislocation rates (2.9% vs. 2.4%, p = 0.600). Total costs in the first ninety days after THA were not different between the LTR and controls (p = 0.756). CONCLUSIONS: These findings suggest that complications and costs are no major point of concern in patients with liver transplant that are operated with THA.

Analyzing the Burden of Revision Total Knee Arthroplasty in the United States between 2009 and 2016.

As the number of total knee arthroplasties (TKAs) increases, it is reasonable to expect the number of revision TKAs (rTKAs) to rise in parallel. The patient-related and societal burdens of rTKA are poorly understood. Therefore, the purpose of this study was to determine temporal changes in: (1) the incidence of rTKA; (2) patient and hospital characteristics; (3) complications, hospital lengths of stay (LOSs), and discharge dispositions; and (4) costs, charges, and payer types. All patients who underwent rTKA between 2009 and 2016 were identified from the National Inpatient Sample database using International Classification of Diseases, Ninth Revision and Tenth Revision codes and were studied. Univariate analyses were performed to compare the incidence of rTKA, patient and hospital characteristics, LOS and discharge dispositions, as well as costs, charges, and payer types. A multivariate logistic regression model was built to compare the odds of complications in 2009 and 2016. Over our study period, there was a 4.3% decrease in the incidence of rTKA. The mean age of patients who underwent rTKA was 65 years and a majority were female (58%). Mean hospital LOS decreased from 4.1 days in 2009 to 3.3 days in 2016 (p < 0.001). The rate of several complications decreased significantly over our study period including myocardial infarction, cardiac arrest, transfusion, pneumonia, urinary tract infection, and mortality. A significantly lower percentage of rTKA patients were discharged to a skilled nursing facility in 2016 (26.5%) compared with 2009 (31.6%; p < 0.001). There was an 18.7% increase in the mean costs, and a 43.3% increase in the mean charges (p < 0.001). Over the study period, there was a decrease in the incidence of rTKAs. Despite potential improvements in primary TKA, the burden associated with rTKA remains large. This report can be used to help educate medical providers about outcomes that may result from a primary and/or revised TKA.

Treatment of Periprosthetic Joint Infection in Total Knee Arthroplasty with a Temporary Intramedullary Nail: Is a Long or Short Nail Better?

To our knowledge, no studies have compared postoperative outcomes between patients who received a temporary short or long intramedullary (IM) nail in the setting of infected total knee arthroplasty (TKA). Therefore, the aim of this study was to compare short-term outcomes for patients who underwent long or short IM nail insertion for treatment of periprosthetic knee infection. Specifically, we compared: (1) success rates; (2) patient reported/functional outcomes; and (3) complications between patients implanted with a short or a long IM nail following PJI of the knee. A retrospective chart review was performed for patients who underwent two-stage exchange arthroplasty with a temporary long or short IM nail between November 2010 and June 2018 at our institution (n = 67). Continuous and categorical variables were assessed using t-test/Mann-Whitney U test and chi-squared test, respectively. Logistic regression analyses were conducted to assess the effect of IM nail length on success rate while adjusting for age, sex, body mass index, and race. A total of 36 patients underwent temporary treatment with a long IM nail, while 31 patients received a short IM nail. There were no differences in success rate for reimplanted patients treated with long and short IM nails (odds ratio 0.992; p = 0.847). Fewer patients with a long IM nail went on to reimplantation (52.8 vs. 83.9%; p = 0.007). There was no difference in satisfaction (7.86 vs. 7.68; p = 0.515), pain scores (3.39 vs. 4.45 points; p = 0.126), or Knee Society score outcome scores (150.61 vs. 166.26 points; p = 0.117) between long or short IM nail patients. Following reimplantation, there was no difference in the number of patients who became reinfected (15.8 vs. 11.5%; p = 0.679) or went on to amputation (0 vs. 7.7%; p = 0.210). Periprosthetic joint infection (PJI) is a rare but serious postoperative complication following TKA. Our findings suggest that the use of long and short IM nails during two-stage exchange can have equal utility in PJI patients with severe bone defects.

Sequentially Irradiated and Annealed Highly Cross-Linked Polyethylene: Clinical and Radiographic Outcomes in Total Knee Arthroplasty at 10-Year Follow-up.

Highly cross-linked polyethylene (HXLPE) has become the preferred bearing surface in total hip arthroplasty. However, its acceptance in total knee arthroplasty (TKA) has not been as robust because of concerns pertaining to wear and its impact on implant failure. Therefore, this multicenter study was purposed to evaluate the 10-year (1) radiographic outcomes; (2) complications; and (3) implant survivorship in patients with TKA receiving a sequentially irradiated and annealed HXLPE. A retrospective, multi-center study was performed on 139 patients (171 TKAs) who underwent primary TKA with HXLPE and possessed a minimum of 10-year follow-up. Radiographs were analyzed for radiolucencies along the implant-fixation interface using the Modern Knee Society Radiographic Evaluation System. Kaplan-Meier analysis determined implant survivorship when the end points were revision for polyethylene wear and polyethylene revision for any reason. Sixteen TKAs (9.9%) demonstrated periprosthetic linear radio-lucencies. Seventeen TKAs (9.9%) required additional surgeries, 9 (5.3%) of which were revisions, with 1 (0.6%) TKA requiring revision because of polyethylene wear. Other causes of revision included instability (1.8%), infection (1.6%), and arthrofibrosis (1.6%). The mean time to revision was 5.9 years (range, 0.1-11.1 years). Survivorship pertaining to polyethylene revision for wear was 99.4%, whereas all-cause polyethylene revision was 94.7%. This study in patients undergoing primary TKA using a second-generation HXLPE demonstrated excellent results with respect to polyethylene wear characteristics and strength with a 99.4% survivorship at 10 years. [Orthopedics. 2023;46(2):e111-e117.].

Subacromial Impingement Syndrome: A Systematic Review of Existing Treatment Modalities to Newer Proprioceptive-Based Strategies.

Musculoskeletal pain is a common reason for primary care visits, with many visits for shoulder pain due to subacromial impingement syndrome (SIS). Current treatments lack evidence for effective management, showing only temporary outcomes. This systematic review evaluates existing modalities in comparison to the use of more permanent proprioceptive-based strategies. Specifically, this meta-analysis compared the use of kinesiology tape, myofascial trigger point release (MPTR), scapular stabilization exercises (SSE), and resistance training. PubMed, BioMedCentral, and ScienceDirect databases were queried for studies evaluating proprioceptive-based exercises in the last nine years. In total, 48 studies met the inclusion and exclusion criteria. After removing duplicates, a total of 14 level 1 studies were left. Kinesiology tape use demonstrated a statistically significant reduction in pain-free range of motion. MPTR improved in all pain scores and the disability scores index. SSE also reduced pain; however, mixed results were seen for range of motion. Finally, resistance training not only reduced pain but improved proprioception and joint position sense. Even though all techniques showed some promise in treating SIS, further large-scale studies exploring related outcomes are needed.

Social Determinants of Health in Total Hip Arthroplasty: Are They Associated With Costs, Lengths of Stay, and Patient Reported Outcomes?

BACKGROUND: Social determinants of health (SDOH) may play a larger role in predicting patient outcomes as outpatient total hip arthroplasty (THA) expands. We specifically examined the association between SDOH and patient metrics (demographics and comorbidities) for: (1) 30-day post-discharge costs of care; (2) lengths of stay (LOS); and (3) patient-reported outcomes (Hip Disability and Osteoarthritis Outcomes Score for Joints Replacement (HOOS JR)). METHODS: Medicare patients who underwent primary THA between 2018 and 2019 were identified. Those who had complete social determinant data were included (n = 136). Data elements were drawn from institutional, regional, and government databases, as well as the Social Vulnerability Index (SVI). Multiple regression analyses were performed to determine SDOH and baseline comorbidities associations with costs, LOS, and HOOS JR scores. RESULTS: Various SDOH factors were associated with higher 30-day costs, including residing in a food desert ($53,695 ± 15,485; P < .001) and the following SVI themes: 'Minority Status and Language' ($24,075 ± 9845; P = .01) and 'Housing and Transportation' ($16,190 ± 8501; P = .06), although the latter did not meet statistical significance. Baseline depression was associated with longer LOS (P = .02), while none of the other SDOH or patient metrics affected LOS. No relationships were observed between SDOH and HOOS JR changes from baseline. CONCLUSION: Patients who live in food deserts and have minority status had higher costs of care after primary THA. Poor housing and transportation may also increase costs, albeit insignificantly. These results highlight the utility of assessing SDOH-related risk factors to optimize post-operative outcomes, with potential implications for bundled care.

National Trends for Reverse Shoulder Arthroplasty After the Affordable Care Act: An Analysis From 2011 to 2015.

Few studies have investigated nationwide patient trends and health care costs for reverse shoulder arthroplasty (RSA) after 2014. This study uses a large validated nationwide database to retrospectively assess changes in patient and hospital demographic features, hospital costs, and hospital charges for inpatient RSA procedures before and after implementation of the Affordable Care Act. The National Inpatient Sample database was used to identify all patients who underwent RSA between January 2011 and December 2015, yielding 163,171 patients (63.4% female; mean age, 72 years). Categorical data were assessed with chi-square/Fisher's exact test, and continuous data were assessed with analysis of variance. There was an increased proportion of RSA recipients identifying as Hispanic (4.1% to 4.8%) and Native American (0.1% to 0.4%; P<.0001). The proportion of patients who had Medicaid (1.4% to 2.4%) and private insurance (15.1% to 16.6%) increased as well (P<.0001). A decrease in mean hospital costs occurred between 2011 and 2015 (-$256; P=.002), whereas an increase occurred in hospital charges (+$6,314; P<.001). These findings provide insight on RSA use and patient demographic trends in the United States. Additionally, these results help to capture the effects of extended health coverage and new reimbursement models on hospital costs and charges. [Orthopedics. 2022;45(2):97-102.].

The pericapsular nerve group block: a step towards outpatient total hip arthroplasty?

INTRODUCTION: A new regional anaesthetic technique, coined the pericapsular nerve group (PENG) block, targets the anterior hip capsule by blocking the articular branches of the femoral nerve and accessory obturator nerve. In this study, we evaluated: (1) patient outcomes; (2) postoperative pain scores; and (3) postoperative opioid consumption in total hip arthroplasty (THA) patients who received a PENG block in comparison to a control group. METHODS: A retrospective chart review was performed for patients who underwent primary THA and met criteria at a single institution (n = 48), with an additional cohort of patients collected as controls (n = 48). Postoperative pain scores were measured by obtaining the cumulative visual analogue scores (VAS) at 12-hour intervals until the 48-hour benchmark. All administered opioids were collected from postoperative day (POD) 0 to POD2 and converted to morphine milligram equivalents (MME). RESULTS: In the PENG group, length of stay was significantly shorter (p < 0.001) and the initial postoperative distance walked was significantly farther (p = 0.001). The PENG group consistently demonstrated significantly lower mean cumulative pain scores until the 48-hour mark (p < 0.001 for all). Patients receiving the PENG block also experienced a significantly longer therapeutic window before requiring their first opioid (p < 0.002). The PENG group required significantly less opioid MMEs on POD1, POD2, and cumulatively over the entire stay (p < 0.022 for all). CONCLUSIONS: Our findings suggest that the PENG block has the potential of impacting THA recovery pathways and contributing to cost savings. Thus, its use further supports the transition to the outpatient setting and drives us towards achieving value-driven healthcare.

Access to Total Knee Arthroplasty Among Patients With Low Incomes Has Not Increased Under Global Budget Revenue.

In 2014, Maryland implemented an experimental reimbursement model, Global Budget Revenue (GBR). This model provided hospitals with a capitated annual budget each fiscal year to use toward all services, regardless of payer. Goals of GBR include reductions in cost, improvements in care quality, and increased access for patients to high-volume procedures, such as total knee arthroplasty (TKA). We assessed demographics and outcomes among patients with low incomes and patients of racial minority groups in Maryland who underwent TKA before and after GBR implementation. Patients undergoing TKAs from 2011 to 2016 were queried from the Maryland State Inpatient Database, resulting in 71,066 patients. There were 13,722 patients with low incomes and 19,846 patients of racial minority groups. The chi-square test was used for sex, income, insurance, Charlson Comorbidity Index, and morbid obesity, with the Student's t test being reserved for age before and after GBR. The proportion of patients with low incomes decreased the year before GBR but increased with GBR and maintained (P<.001). The proportion of patients of racial minority groups increased the year before GBR implementation, decreased slightly, and then maintained (P<.001). Mean cost decreased for both cohorts of patients (both P<.001). Discharges to home increased for both cohorts (P<.001), while length of stay decreased (both P<.001). Global Budget Revenue decreased cost while improving outcomes for TKA patients post-GBR. Patients with low incomes have not increased their use of TKA, contrary to patients of racial minority groups. This suggests that barriers remain. Further follow-up of GBR performance in subsequent years will increase understanding of the sustainability of this trend and the degree to which any increase in access is dependent on the implementation of the Affordable Care Act. [Orthopedics. 2022;45(1):e11-e16.].

Utilisation of calcium sulphate beads in one-stage aseptic revision total hip arthroplasty.

INTRODUCTION: Periprosthetic joint infection (PJI) affects many revision total hip arthroplasty (THA) patients, contributing to a concomitant rise in revision costs. Means of decreasing the risk of PJI include the use of antibiotic adjuncts, such as calcium sulphate beads (CSBs). Mixed with antibiotics, the potential benefits of CSBs include dissolvability and antibiotic drug elution. However, information comparing them in aseptic revision is scarce. Therefore, this study investigated CSB utilisation for infection prevention in aseptic revision THA. Specifically, we compared (1) infection rates; (2) lengths of stay; (3) subsequent infection procedures; and (4) final surgical outcome in 1-stage aseptic revision THA patients who did received CSBs to 1-stage aseptic revision THA patients who did not. METHODS: A retrospective chart review was performed to identify all patients who underwent an aseptic revision THA between January 2013 and December 2017. Patients who received CSBs (n = 48) were compared to non-CSB patients (n = 58) on the following outcomes: postoperative infections, lengths of stay (LOS), subsequent irrigation and debridements (I+Ds), and final surgical outcome, classified as successful THA reimplantation, retained antibiotic spacer, or Girdlestone procedure. Chi-square and t-testing were used to analyse the variables. RESULTS: There was no significant differences found between CSB patients and non-CSB patients in postoperative infections (p = 0.082), LOS (p = 0.179), I+Ds (p = 0.068), and final surgical outcome (p = 0.211). CONCLUSION: This study did not find any statistical difference between CSBs and standard of care in infection rates and surgical outcomes. The advantage of these beads for 1-stage aseptic revisions is questionable.

Inpatient dislocation after primary total hip arthroplasty: incidence and associated patient and hospital factors.

INTRODUCTION: Inpatient dislocation following total hip arthroplasty (THA) may incur substantial financial penalties for hospitals in the United States. However, limited studies report on current incidence and variability of dislocations. We utilised a large national database to evaluate inpatient hip dislocation trends regarding: (1) yearly incidences; (2) lengths of stay (LOS); (3) demographic factors; and (4) hospital metrics. METHODS: The National Inpatient Sample was queried from 2012 to2016 for primary THA patients (n = 1,610,155), identifying 2490 inpatient dislocations. Various patient demographics and hospital characteristics were assessed. Multivariate regression analyses were conducted to identify dislocation risk factors. RESULTS: Dislocation rates increased from 0.11% in 2012 to 0.18% in 2016 (p < 0.001). Dislocated patients experienced significantly longer LOS (p < 0.001). Patient demographic factors associated with dislocation were sex, race, Medicaid insurance, alcohol use disorder, psychosis, hemiparesis/hemiplegia, chronic renal failure, and obesity. Spinal fusion was not associated with inpatient dislocation. Dislocations were likeliest in the South and least likely in teaching hospitals. CONCLUSION: Inpatient dislocation has increased in recent years. Optimised management and recognition of the patient and hospital factors outlined in this study may help decrease inpatient dislocation risks following THA, thus avoiding hospital reimbursement penalties for this preventable complication.

The Rise of Obesity among Total Knee Arthroplasty Patients.

In the United States, one-third of adults are considered obese, and demand for total knee arthroplasty (TKA) is expected to rise in these patients. Surgeons are reluctant to operate on obese patients, but it is important to understand how obesity has affected TKA utilization. This study utilizes a national database to evaluate incidence, demographics, outcomes, charges, and cost in nonobese, overweight, nonmorbidly obese, and morbidly obese TKA patients. We queried the National Inpatient Sample from 2009 to 2016 for primary TKA patients identifying 4,053,037 nonobese patients, 40,077 overweight patients, 809,649 nonmorbidly obese patients, and 428,647 morbidly obese patients. Chi-square was used to analyze categorical variables, and one-way analysis of variance was used to analyze continuous variables. Nonmorbidly obese and morbidly obese patients represented 23.2% of all TKAs. TKA utilization increased 4.1% for nonobese patients, 121.6% for overweight patients, 73.6% for nonmorbidly obese patients, and 83.9% for morbidly obese patients. Morbidly obese patients were younger (p < 0.001), female (p < 0.001), Black (p < 0.001), poor (p < 0.001), and utilized private insurance (p < 0.001). They also had the longest length of stay (p < 0.001) and the highest mortality rate (p < 0.001). More morbidly obese patients were discharged to other facilities (p < 0.001), and they had the highest rate of complications (p < 0.001). Patients with morbid obesity had the highest charges (p < 0.001), but overweight patients had the highest costs (p < 0.001). The results of this study demonstrate the rise in obese and morbidly obese patients seeking TKAs, which may be reflection of the obesity epidemic in America. Although TKA utilization has increased for morbidly obese patients, this body mass index (BMI) category also has the highest rates of charges and complications, suggesting morbid obesity to be a modifiable risk factor leading to worse surgical and economic outcomes. Obese patients undergoing TKA may benefit from preoperative optimization of their weight, in an effort to reduce the risk of adverse outcomes.

Sequentially Irradiated and Annealed Highly Cross-Linked Polyethylene: Linear Vector and Volumetric Wear in Total Hip Arthroplasty at 10 Years.

BACKGROUND: There is a paucity of data on the long-term performance of highly cross-linked polyethylene (HXLPE). Therefore, this study evaluated 10-year 1) functional, 2) radiographic, and 3) surgical outcomes in patients who underwent total hip arthroplasty with sequentially irradiated and annealed HXLPE. METHODS: A retrospective, multicenter study was conducted on patients who underwent primary total hip arthroplasty and received HXLPE polymer (n = 151). Two-dimensional radiographic linear and volumetric wear analyses were quantified using the Martell Hip Analysis software, while functional outcomes were assessed by analyzing postoperative Short-Form-12 (SF-12) Physical and Mental Health Surveys and Harris Hip Scores. Radiographic outcomes included yearly linear (mm/y) and volumetric (mm3/y) wear rates. Surgical outcomes included additional operations and survivorship. RESULTS: SF-12 scores were within 1 standard deviation (SD) of the normal population (SF-12 Physical: 47.0; SF-12 Mental: 52.0), while the Harris Hip Scores of 89.5 was borderline between "good" and "excellent." Total and annual linear wear rates were 0.164 mm (SD: 0.199 mm) and 0.015 mm/y (SD: 0.018 mm/y), respectively. The mean total volumetric wear rate was 141.4 mm3 (SD: 165.0) and 12.6 mm3/y (SD: 14.9 mm3/y) when broken down into a yearly rate. Eleven patients required revisions, resulting in an all-cause polyethylene survivorship of 92.7%, with a polyethylene wear survivorship of 100.0%. CONCLUSIONS: Our results demonstrate clinically undetectable linear and volumetric wear rates after 10 years in those who received the unique sequentially irradiated and annealed HXLPE. Furthermore, high rates of survivorship coupled with low all-cause revision rates illustrate the polymers' capability to potentially increase implant longevity.

Comparing Primary Total Hip Arthroplasty in Renal Transplant Recipients to Patients on Dialysis for End-Stage Renal Disease: A Nationally Matched Analysis.

BACKGROUND: Renal transplants are the most commonly performed solid-organ transplants worldwide. It is unclear whether a kidney transplant is associated with reduced postoperative complications in comparison with patients on dialysis for end-stage renal disease (ESRD). The purpose of this study was to utilize a national database to compare readmissions, complications, and costs associated with primary total hip arthroplasty (THA) between matched renal transplant recipients (RTRs) and patients on dialysis for ESRD. METHODS: Patients with a renal transplant (N = 1,401) and those on dialysis for ESRD (without a transplant) (N = 1,463) prior to being treated with a THA from 2010 to 2019 were identified within the PearlDiver database. RTRs and patients on renal dialysis were frequency-matched 1:1 on the basis of 9 patient characteristics, resulting in 582 patients in each group. Length of hospital stay, readmissions, complication rates up to 2 years, and total costs up to 1 year were compared between the groups using chi-square and multivariable logistic regression analyses to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Patients on renal dialysis had an increased mean length of stay (6.3 days) compared with RTRs (4.6 days, p < 0.01). After adjusting for age, tobacco use, and diabetes, patients on renal dialysis were more likely to be readmitted by 90 days (OR = 1.59; CI = 1.11 to 2.29, p < 0.01) and have mechanical complications (OR = 2.13; CI = 1.08 to 4.45, p = 0.03) and revisions (OR = 2.14; CI = 1.14 to 4.01, p = 0.01) by 2 years. Patients on renal dialysis were also more likely to have periprosthetic joint infections at 1 year (OR = 1.91; CI = 1.02 to 3.71, p = 0.04). Patients on dialysis incurred 14% higher costs at 1 year (p = 0.11). CONCLUSIONS: Patients on renal dialysis had more readmissions, complications, and costs after THA when compared with RTRs. Specifically, patients on renal dialysis were more likely to have longer index lengths of stay, more readmissions by 90 days, and more mechanical complications and revision surgery by 2 years. Patients on dialysis also incurred higher costs and had greater odds of PJI. These results suggest that joint surgeons may consider delaying THA in suitable patients until after renal transplantation to reduce postoperative complications and costs. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Effect of Modern Antiretroviral Therapy on Complication Rates After Total Hip Arthroplasty.

BACKGROUND: Antiretroviral therapy (ART) remains the cornerstone of decreasing morbidity and mortality in patients with human immunodeficiency virus (HIV), but additional information on its impact on total hip arthroplasty (THA) complication rates is needed to mitigate risks postoperatively. Therefore, we sought to examine patients with HIV who were and were not taking ART compared with a cohort without HIV in the setting of primary THA with respect to the following outcomes: length of stay, readmissions, and postoperative infection. METHODS: A retrospective database review was performed with PearlDiver for patients who underwent THA from 2010 to 2019 (n = 729,101). Patients with HIV who were and were not taking ART were then identified and were matched with patients without HIV at a 1:1:1 ratio based on age, sex, Charlson Comorbidity Index, diabetes, obesity, and tobacco use, resulting in 601 patients in each cohort. Length of stay, 30-day readmissions, and complications at 90 days and 1 year were analyzed. Continuous outcomes were measured via Student t tests, and categorical outcomes were measured via chi-square analyses. RESULTS: Patients with HIV who were and were not taking ART were found to have similar lengths of stay compared with patients without HIV (range, 4.1 to 4.3 days). Readmission rates were slightly higher in patients with HIV who were taking ART at 4.2% (odds ratio [OR], 1.96 [95% confidence interval (CI), 0.99 to 3.87]) and patients with HIV who were not taking ART at 3.5% (OR, 1.63 [95% CI, 0.81 to 3.30]) compared with patients without HIV at 2.1%. Periprosthetic joint infection rates at 1 year were slightly higher among patients with HIV who were not taking ART at 5.3% (OR, 1.41 [95% CI, 0.82 to 2.45]) compared with patients with HIV who were taking ART at 4.2% (OR, 1.09 [95% CI, 0.61 to 1.94]) and patients without HIV at 3.8%. CONCLUSIONS: Patients with HIV who are and are not taking ART are approaching normalization to the general population in the setting of THA. It is important to note that, although complications may have been mitigated by modern therapy, extreme care should be taken while clinically evaluating these patients prior to the surgical procedure given the complexity of their clinical status. The findings of this study underscore the utility of ART and patient optimization to reduce risk in this patient population. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Social determinants of health in total knee arthroplasty : are social factors associated with increased 30-day post-discharge cost of care and length of stay?

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. METHODS: Patients who underwent TKA between 1 January 2018 and 31 December 2019 were identified. A total of 234 patients with complete SDOH data were included. Data were drawn from the Chesapeake Regional Information System, the Centers for Disease Control social vulnerability index (SVI), the US Department of Agriculture, and institutional electronic medical records. The SVI identifies areas vulnerable to catastrophic events with four themed scores: socioeconomic status; household composition and disability; minority status and language; and housing and transportation. Food deserts were defined as neighbourhoods located one or ten miles from a grocery store in urban and rural areas, respectively. Multiple regression analyses were performed to determine associations with LOS and costs after controlling for various demographic parameters. RESULTS: Divorced status was significantly associated with an increased LOS (p = 0.043). Comorbidities significantly associated with an increased LOS included chronic obstructive pulmonary disease/asthma and congestive heart failure (p = 0.043 and p = 0.001, respectively). Communities with a higher density of tobacco stores were significantly associated with an increased LOS (p = 0.017). Comorbidities significantly associated with an increased TCOC included chronic obstructive pulmonary disease (p = 0.004), dementia (p = 0.048), and heart failure (p = 0.007). Increased TCOCs were significantly associated with patients who lived in food deserts (p = 0.001) and in areas with an increased density of tobacco stores (p = 0.023). CONCLUSION: Divorced marital status was significantly associated with an increased LOS following TKA. Living in food deserts and in communities with more tobacco stores were significant risk factors for increased LOS and TCOC. Food access and ease of acquiring tobacco may both prove to be prognostic of outcome after TKA and an opportunity for intervention. Cite this article: Bone Joint J 2021;103-B(6 Supple A):113-118.

Complications Associated With Same-Day Bilateral Total Knee Arthroplasties.

Same-day bilateral total knee arthroplasties (SBTKAs) are associated with shorter rehabilitation and lower cost. However, controversy surrounding the safety of SBTKAs exists. Recent studies are lacking to determine whether patient selection has brought SBTKA in line with unilateral total knee arthroplasty (UTKA). Therefore, the authors evaluated and compared patient characteristics, hospital characteristics, and inpatient course between UTKA and SBTKA from 2009 to 2016. The National Inpatient Sample was queried from 2009 to 2016 for UTKA and SBTKA patients. Of the 5,329,466 patients identified, 5,084,328 (95.4%) patients received UTKAs and 245,138 (4.6%) patients underwent SBTKAs. Incidence, rate, patient and hospital characteristics, health status, length of stay (LOS), discharge disposition, hospital charges, hospital costs, and complications were analyzed and statistically compared. The incidence (-1.4%) and rate (15.8%) of SBTKAs decreased (both P<.001). The SBTKA cohort had more patients who were younger, male, White, obese, healthier, and using private insurance (P<.001 for all). The SBTKA cohort had longer LOS, a higher proportion of discharges to skilled nursing facilities, higher cost and charges, and more complications, including deep venous thromboses/pulmonary emboli (DVT/PE) and transfusions (P<.001 for all). Conversely, SBTKA was associated with fewer myocardial infarctions (P<.001). Although improved from previous literature, SBTKA is still associated with longer LOS, higher cost and charges, and more complications, including DVT/PE and transfusions, although with a lower rate of myocardial infarction. However, studies are needed to determine whether the risk of 1 SBTKA outweighs the cumulative risk of staged UTKAs. [Orthopedics. 2021;44(3):e407-e413.].

Spaceflight and hind limb unloading induces an arthritic phenotype in knee articular cartilage and menisci of rodents.

Reduced knee weight-bearing from prescription or sedentary lifestyles are associated with cartilage degradation; effects on the meniscus are unclear. Rodents exposed to spaceflight or hind limb unloading (HLU) represent unique opportunities to evaluate this question. This study evaluated arthritic changes in the medial knee compartment that bears the highest loads across the knee after actual and simulated spaceflight, and recovery with subsequent full weight-bearing. Cartilage and meniscal degradation in mice were measured via microCT, histology, and proteomics and/or biochemically after: (1) ~ 35 days on the International Space Station (ISS); (2) 13-days aboard the Space Shuttle Atlantis; or (3) 30 days of HLU, followed by a 49-day weight-bearing readaptation with/without exercise. Cartilage degradation post-ISS and HLU occurred at similar spatial locations, the tibial-femoral cartilage-cartilage contact point, with meniscal volume decline. Cartilage and meniscal glycosaminoglycan content were decreased in unloaded mice, with elevated catabolic enzymes (e.g., matrix metalloproteinases), and elevated oxidative stress and catabolic molecular pathway responses in menisci. After the 13-day Shuttle flight, meniscal degradation was observed. During readaptation, recovery of cartilage volume and thickness occurred with exercise. Reduced weight-bearing from either spaceflight or HLU induced an arthritic phenotype in cartilage and menisci, and exercise promoted recovery.

Closing the Socioeconomic Gap in Massachusetts: Trends in Total Hip Arthroplasty From 2013 to 2015.

To extend insurance coverage to all residents, Massachusetts legislation expanded Medicaid eligibility and added new private insurance categories. To date, no one has analyzed the effect of these changes and compared recent trends in total hip arthroplasty (THA) utilization. Therefore, this study sought to update the current trends of THA utilization in Massachusetts from 2013 to 2015. The Massachusetts State Inpatient Database was queried for all patients who underwent primary THA between 2013 and 2015, and 30,308 patients were identified. Analyzed variables included age, sex, race, Charlson Comorbidity Index, median household income, primary payer, discharge disposition, length of stay, hospital charges, hospital costs, and complications. Categorical and continuous variables were assessed using chi-square analyses and analyses of variance, respectively. Between 2013 and 2015, annual THAs increased from 9361 to 10,562. Race did not vary significantly (P=.447), although an increase in patients using Medicaid and a decrease in patients using other insurance was observed (P<.001). Patients with an income quartile of 1 increased, whereas the number of THA patients in quartile 3 decreased (P<.001). There was a decrease in both hospital charges (P<.001) and costs (P<.001). Mean length of stay decreased (P<.001), and the number of patients with complications decreased (P<.001). Massachusetts has been successful in increasing access to THA procedures for low-income patients and increasing the number of patients who use Medicaid for THAs. The current delivery of health care in Massachusetts has shown improvement for its residents, serving as an example that other states can learn from. [Orthopedics. 2021;44(2):e167-e172.].