The Effect of Femoral Fixation on Revision and Mortality Following Elective Total Hip Arthroplasty in Patients Over the Age of 65 years. An Analysis of the American Joint Replacement Registry.

BACKGROUND: With the overwhelming use of cementless femoral fixation for primary total hip arthroplasty in the United States, the associations of stem fixation on the risk of revision and mortality are poorly understood. We evaluated the relationship between femoral fixation and risk of revision and mortality in patients included in the American Joint Replacement Registry. METHODS: Elective, primary, unilateral total hip arthroplasties in the American Joint Replacement Registry, in patients over the age of 65 years were considered. In total, 9,612 patients with a cemented stem were exact matched 1:1 with patients who received a cementless stem based on age, gender, and the Charlson Comorbidity Index. Outcomes compared between the groups included need and reason for revision at 90 days and 1 year; in-hospital, 90-day, and 1-year mortality; and mortality after early revision. Covariates were used in linear regression analyses. RESULTS: Cemented fixation was associated with a 37% reduction in the risk of 90-day revision, and a reduction in the risk of revision for periprosthetic fracture of 87% at 90 days and 81% at 1 year. Cemented fixation was associated with increased 90-day and 1-year mortality (odds ratio [OR] 3.15, confidence interval [CI] 2.24-4.43 and OR 2.36, CI 1.86-3.01, respectively). Patients who underwent subsequent revision surgery within the first year exhibited the highest mortality risk (OR 3.23, CI 1.05-9.97). CONCLUSION: In this representative sample of the United States, 90-day revision for any reason and for periprosthetic fracture was significantly reduced in patients with a cemented stem. This benefit must be weighed against the association with increased mortality and with the high risk of mortality associated with early revision, which was more prevalent with cementless fixation.

Effects of Hospital and Surgeon Volume on Patient Outcomes After Total Joint Arthroplasty: Reported From the American Joint Replacement Registry.

BACKGROUND: The purpose of this study was to evaluate outcomes and complications because it relates to surgeon and hospital volume for patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) using the American Joint Replacement Registry from 2012 to 2017. METHODS: A retrospective study was conducted on Medicare-eligible cases of primary elective THAs and TKAs reported to the American Joint Replacement Registry database and was linked with the available Centers of Medicaid and Medicare Services claims and the National Death Index data from 2012 to 2017. Surgeon and hospital volume were defined separately based on the median annual number of anatomic-specific total arthroplasty procedures performed on patients of any age per surgeon and per hospital. Values were aggregated into separate surgeon and hospital volume tertile groupings and combined to create pairwise comparison surgeon/hospital volume groupings for hip and knee. RESULTS: Adjusted multivariable logistic regression analysis found low surgeon/low hospital volume to have the greatest association with all-cause revisions after THA (odds ratio [OR], 1.63, 95% confidence interval [CI], 1.41-1.89, P < 0.0001) and TKA (OR, 1.72, 95% CI, 1.44-2.06, P < 0.0001), early revisions because of periprosthetic joint infection after THA (OR, 2.50, 95% CI, 1.53-3.15, P < 0.0001) and TKA (OR, 2.18, 95% CI, 1.64-2.89, P < 0.0001), risk of early THA instability and dislocation (OR, 2.47, 95% CI, 1.77-3.46, P < 0.0001), and 90-day mortality after THA (OR, 1.72, 95% CI, 1.27-2.35, P = 0.0005) and TKA (OR, 1.47, 95% CI, 1.15-1.86, P = 0.002). CONCLUSION: Our findings demonstrate considerably greater THA and TKA complications when performed at low-volume hospitals by low-volume surgeons. Given the data from previous literature including this study, a continued push through healthcare policies and healthcare systems is warranted to direct THA and TKA procedures to high-volume centers by high-volume surgeons because of the evident decrease in complications and considerable costs associated with all-cause revisions, periprosthetic joint infection, instability, and 90-day mortality. LEVEL OF EVIDENCE: III.

Trends of Femoral Neck Fracture Treatment Using Total Hip Arthroplasty: Reported From the American Joint Replacement Registry.

INTRODUCTION: Total hip arthroplasty (THA) rather than hemiarthroplasty for displaced femoral neck fracture (FNF) is often chosen for younger patients who are more active and/or have underlying hip osteoarthritis. However, instability remains the primary concern of doing THA. Dual mobility (DM) has been shown to decrease this risk through a larger effective head size and greater head-to-neck ratio compared with conventional THA. The purpose of this study was to identify femoral head size and DM usage patterns for the treatment of FNF with THA in the United States using the American Joint Replacement Registry. METHODS: A retrospective cohort study was conducted, including all primary THAs done for FNF from 2012 to 2019. THA and FNF were defined using Current Procedural Terminology or International Classification of Diseases-9 or -10 diagnosis and procedure codes. Analysis was based on patient demographics, femoral head size, and DM usage. Descriptive statistics were used using a Pearson chi-square test. All analyses were conducted using SAS version 9.4, and statistical significance was set at P < 0.05. RESULTS: There were 18,752 THAs done by 3,242 surgeons at 789 institutions during the 8-year study period. The overall population was 66% female, and the mean age was 72.3 ± 11.8 years. The most commonly used femoral head size was 36 mm (48.5%) followed by 32 mm (24.5%), ≤28 mm (10.7%), DM (10.8%), and ≥40 mm (5.7%). A trend was observed toward decreased use of ≤28, 32, and ≥40-mm heads starting in 2016 across the years and increased use of 36-mm heads (P < 0.0001). A significant increase was observed in the usage of DM over time from 6.4% in 2012 to 16.2% in 2019 (P < 0.0001). DISCUSSION: Most of the femoral heads used were ≥36 mm, and the use of DM increased during the study period. Additional analysis is warranted to understand how these trends will affect overall outcomes and postoperative dislocation rates.

Cementless Fixation Is Associated With Increased Risk of Early and All-Time Revision After Hemiarthroplasty But Not After THA for Femoral Neck Fracture: Results From the American Joint Replacement Registry.

BACKGROUND: Despite ample evidence supporting cemented femoral fixation for both hemiarthroplasty and THA for surgical treatment of displaced femoral neck fractures, cementless fixation is the preferred fixation method in the United States. To our knowledge, no nationally representative registry from the United States has compared revision rates by fixation for this surgical treatment. QUESTION/PURPOSE: After controlling for relevant confounding variables, is femoral fixation method (cemented or cementless) in hemiarthroplasty or THA for femoral neck fracture associated with a greater risk of (1) all-cause revision or (2) revision for periprosthetic fracture? METHODS: Patients with Medicare insurance who had femoral neck fractures treated with hemiarthroplasty or THA reported in the American Joint Replacement Registry database from 2012 to 2017 and Centers for Medicare and Medicaid Services claims data from 2012 to 2017 were analyzed in this retrospective, large-database study. Of the 37,201 hemiarthroplasties, 42% (15,748) used cemented fixation and 58% (21,453) used cementless fixation. Of the 7732 THAs, 20% (1511) used cemented stem fixation and 80% (6221) used cementless stem fixation. For both the hemiarthroplasty and THA cohorts, most patients were women and had cementless femoral fixation. Early revision was defined as a procedure that occurred less than 90 days from the index procedure. All patients submitted to the registry were included in the analysis. Patient follow-up was limited to the study period. No patients were lost to follow-up. Due to inherent limitations with the registry, we did not compare medical complications, including deaths attributed directly to cemented fixation. A logistic regression model including the index arthroplasty, age, gender, stem fixation method, hospital size, hospital teaching affiliation, and Charlson comorbidity index score was used to determine associations between the index procedure and revision rates. RESULTS: For the hemiarthroplasty cohort, risk factors for any revision were cementless stem fixation (odds ratio 1.42 [95% confidence interval 1.20 to 1.68]; p < 0.001), younger age (OR 0.96 [95% CI 0.95 to 0.97]; p < 0.001), and higher Charlson comorbidity index (OR 1.06 [95% CI 1.02 to 1.11]; p = 0.004). Risk factors for early revision were cementless stem fixation (OR 1.77 [95% CI 1.43 to 2.20]; p < 0.001), younger age (OR 0.98 [95% CI 0.97 to 0.99]; p < 0.001), and higher Charlson comorbidity index (OR 1.09 [95% CI 1.04 to 1.15]; p < 0.001). Risk factors for revision due to periprosthetic fracture were cementless fixation (OR 6.19 [95% CI 3.08 to 12.42]; p < 0.001) and higher Charlson comorbidity index (OR 1.16 [95% CI 1.06 to 1.28]; p = 0.002). Risk factors for early revision due to periprosthetic fracture were cementless fixation (OR 7.38 [95% CI 3.17 to 17.17]; p < 0.001), major teaching hospital (OR 2.10 [95% CI 1.08 to 4.10]; p = 0.03), and higher Charlson comorbidity index (OR 1.20 [95% CI 1.09 to 1.33]; p < 0.001). For the THA cohort, there were no associations. CONCLUSION: These data suggest that cemented fixation should be the preferred technique for most patients with displaced femoral neck fractures treated with hemiarthroplasty. The fact that stem fixation method did not affect revision rates for those patients with displaced femoral neck fractures treated with THA may be due to current practice patterns in the United States. LEVEL OF EVIDENCE: Level III, therapeutic study.

Local Infiltration Analgesia With Liposomal Bupivacaine Improves Early Outcomes After Total Knee Arthroplasty: 24-Hour Data From the PILLAR Study.

BACKGROUND: Enhanced postoperative care pathways have shifted total knee arthroplasty (TKA) to outpatient and short-stay settings, placing greater emphasis on predischarge outcomes. In this study, we report prespecified secondary and tertiary end points of the PILLAR study within 24 hours after TKA in patients receiving local infiltration analgesia (LIA) with or without liposomal bupivacaine (LB). METHODS: Patients with knee osteoarthritis were randomized 1:1 to receive LIA with LB 266 mg/20 mL admixed with bupivacaine HCl 0.5% 20 mL (n = 70) or bupivacaine HCl alone (n = 69). End points (0-24 hours postsurgery) were proportion of opioid-free patients, opioid consumption, areas under the curve of visual analog scale pain intensity scores, patient satisfaction, discharge readiness, and ambulation. Safety was also assessed. RESULTS: Patients receiving LIA with LB were 16% less likely to require opioid rescue within 24 hours postsurgery (17.1% vs 1.4%; relative risk, 0.085; 95% confidence interval, 0.011-0.633). LIA with LB was associated with a 91% reduction in opioid consumption (P = .0009) and 19% reduction in pain intensity (P = .0142). Significantly more patients receiving LB were discharge ready (42.9% vs 27.5%; P = .0449) and satisfied with pain treatment (84.6% vs 69.2%; P = .0306). A numerically lower but not significantly different proportion achieved steady gait/no dizziness with LIA with LB (42.9% vs 52.2%). Adverse event incidence was similar between groups. CONCLUSION: LIA with LB 266 mg plus bupivacaine HCl significantly reduced opioid requirements and pain intensity and significantly improved discharge readiness and satisfaction 0-24 hours after TKA compared with bupivacaine HCl alone. These findings support the use of LIA with LB for TKA when early discharge is the goal.

Impact of Intravenous Acetaminophen on Lengths of Stay and Discharge Status after Total Knee Arthroplasty.

Postoperative pain remains difficult to control after total knee arthroplasty (TKA). While various modalities have been used, they have been associated with several side effects. For example, opioids have many side effects including: sedation, dizziness, nausea, vomiting, constipation, respiratory depression, and can lead to dependency. Recently, intravenous (IV) acetaminophen has been introduced as a method to manage postoperative pain. Therefore, the purpose of this study was to compare the postoperative outcomes of TKA patients who received oral acetaminophen versus IV acetaminophen. Specifically, this study evaluated: (1) the hospital lengths of stay (LOS) and (2) discharge dispositions. The Premier Database was used to review patients who underwent TKA from 2012 to 2015. A total of 134,216 TKA patients received oral acetaminophen, whereas 56,475 TKA patients received IV acetaminophen postoperatively. LOS were calculated as the number of days from the date of hospital admission to the date of discharge, and the discharge disposition was categorized as to home or to a skilled nursing facility (SNF). Compared with the oral group, the IV acetaminophen group had a 0.14 days shorter LOS (95% confidence interval [CI], -0.15 to -0.13; p < 0.001) and 22% higher chance of being discharged home (odds ratio [OR] = 1.22; 95% CI, 1.19-1.25; p < 0.001). Also, compared with the oral group, the IV group had a 13% lower chance of being discharged to a SNF (OR = 0.87; 95% CI, 0.85-0.90; p < 0.001). This study demonstrated that TKA patients who received IV acetaminophen were associated with a significantly shorter hospital LOS as well as being discharged home and fewer patients had to go to SNF. This may lead to a reduction in the total cost of health care, while, at the same time, decreasing the resource use in patients who undergo TKA.

Intravenous Acetaminophen May Be Associated with Reduced Odds of 30-Day Readmission after Total Knee Arthroplasty.

The purpose of this study was (1) to evaluate 30-day readmission rates in total knee arthroplasty (TKA) patients who either received intravenous (IV) or oral (PO) acetaminophen (APAP) perioperatively and (2) to extrapolate the potential annual cost savings on the national level. This was a review of 190,691 TKA recipients between the years 2012 and 2015 who received either IV (n = 56,475) or PO APAP (n = 134,216). All-cause readmissions that occurred between patient discharge and 30 days postdischarge were recorded. Continuous and categorical variables were evaluated using t-test and chi-square test, respectively. A logistic regression analysis was conducted to assess the effect of IV APAP on 30-day readmission. We also performed a literature review on 30-day readmission rates and risk prediction tools for TKA and correlated these with our findings. In addition, we extrapolated potential cost savings on the national level. The readmission rate was 0.04% in the IV and 0.14% in the PO APAP cohort (69% decreased risk; odds ratio = 0.31; 95% confidence interval = 0.20-0.47; p < 0.001). The readmission rate in this patient population appears to be markedly lower, when compared with previous reports. This reduction in readmissions may potentially result in $160 million savings per year. The use of IV APAP in TKA patients resulted in lower readmission rates, which may be valuable in clinical decision making by surgeons and health care administrators looking to lower costs of care.

The Role of Barbed Sutures in Wound Closure Following Knee and Hip Arthroplasty: A Review.

Lower extremity joint arthroplasty procedures often require a large incision to have an adequate exposure, which subsequently leads to lengthy wounds that may contribute to long closure, anesthesia, and overall operative times. The recently introduced knotless barbed suture may provide better outcomes, faster closure time, and decreased material utilization. Therefore, the aim of this study was to review the impact of barbed sutures on: (1) wound-related complications; (2) closure and operative time; (3) patient outcomes (range of motion and Knee Society Scores [KSS]); and (4) effects on cosmesis and patients' satisfaction. A literature search was performed using up to February 2017. Barbed sutures were associated with shorter closure times, shorter operative times, and larger cost savings per procedure as well as comparable wound complication rates after total joint arthroplasty. Although the current review is limited by the number of studies included, it demonstrates that overall, barbed sutures contribute to surgical efficiency when compared with conventional skin closure modalities.

Local Infiltration Analgesia With Liposomal Bupivacaine Improves Pain Scores and Reduces Opioid Use After Total Knee Arthroplasty: Results of a Randomized Controlled Trial.

BACKGROUND: Local infiltration analgesia (LIA) with liposomal bupivacaine (LB) in patients undergoing total knee arthroplasty (TKA) has yielded mixed results. The PILLAR study, which was designed to minimize limitations associated with previous studies, compared the effects of LIA with or without LB on pain scores, opioid consumption, including proportion of opioid-free patients, time to first opioid rescue, and safety after primary unilateral TKA. METHODS: Patients (N = 140) were randomized to LIA with LB 266 mg/20 mL (admixed with bupivacaine HCl 0.5%, 20 mL) or LIA with bupivacaine HCl 0.5%, 20 mL. Standardized infiltration techniques and a standardized multimodal pain management protocol were used. The coprimary efficacy endpoints were area under the curve (AUC) of visual analog scale pain intensity scores 12-48 hours (AUC12-48) postsurgery and total opioid consumption 0-48 hours postsurgery. RESULTS: Mean AUC12-48 of visual analog scale pain intensity score was 180.8 with LB and 209.3 without LB (least squares [LS] mean treatment difference -26.88, P = .0381). LS mean total opioid consumption 0-48 hours postsurgery was 18.7 mg with and 84.9 mg without LB (LS ratio 0.220, P = .0048). Significant differences in favor of LB were observed for the percentage of opioid-free patients (P < .01) and time to first opioid rescue (P = .0230). Treatments were similarly well tolerated. CONCLUSION: This study provides data on LIA with LB administered using optimal techniques specific to TKA. In this setting, LIA with LB significantly improved postsurgical pain, opioid consumption, and time to first opioid rescue, with more opioid-free patients and no unexpected safety concerns.

Eight Hundred Twenty-Five Medial Mobile-Bearing Unicompartmental Knee Arthroplasties: The First 10-Year US Multi-Center Survival Analysis.

BACKGROUND: FDA approval for the Oxford phase III device was approved for use in the United States in 2004. This study seeks to provide the first long-term, large patient sample size, Oxford phase III multi-site survivorship study in the United States, investigating patient reported outcomes of pain and function, while also providing an in-depth analysis of causes for revision, and finally addressing recent advancements that can help aid the unicompartmental knee arthroplasty (UKA) process and further improve partial knee survivorship. METHODS: Between July 2004 and December 2006, 5 surgeons from around the United States performed medial UKA through the minimally invasive surgical approach, on 825 knees in 695 patients. This was a consecutive series of primary UKAs using the phase III mobile bearing; cemented Oxford Knee (Zimmer Biomet, Warsaw, IN), implanted utilizing phase III instrumentation. UKA survivorship considered all revisions as the end point. Implant survivorship eliminated revisions at which the original Oxford implant was determined to be well fixated and functional intra-operatively. RESULTS: A total of 93 knees were revised in this study. Mean follow-up was 9.7 years (6-12). Implant survivorship at year 10 was 90% (confidence interval 2.7%). UKA survivorship at year 10 was 85% (confidence interval 3.8%). Average preoperative American Knee Society Score (knee score) was 49 and rose to 90 postoperatively (standard deviations 16 and 18, respectively). Average preoperative American Knee Society Score (function score) was 55 and rose to 77 postoperatively (standard deviations 15 and 28, respectively). CONCLUSION: This was the first large-scale, 10-year, multi-site follow-up of the Oxford mobile-bearing medial UKA undertaken in the United States, displaying good survivorship and excellent patient outcomes.

No Difference in Early Analgesia Between Liposomal Bupivacaine Injection and Intrathecal Morphine After TKA.

BACKGROUND: Opioid analgesics have been a standard modality for postoperative pain management after total knee arthroplasty (TKA) but are also associated with increased risk of nausea, pruritus, vomiting, respiratory depression, prolonged ileus, and cognitive dysfunction. There is still a need for a method of anesthesia that can deliver effective long-term postoperative pain relief without incurring the high cost and health burden of opioids and nerve blocks. QUESTIONS/PURPOSES: (1) Is liposomal bupivacaine-based periarticular injection (PAI) more effective than morphine-based spinal anesthesia or ropivacaine-based PAI in controlling postoperative pain after TKA? (2) Do patients treated with liposomal bupivacaine-based PAI experience fewer opioid-related adverse events compared with patients treated with morphine-based spinal anesthesia or ropivacaine-based PAI in controlling postoperative pain after TKA? METHODS: This multicenter, blind trial randomized 119 patients undergoing TKA with spinal anesthesia to receive spinal anesthesia plus periarticular injection with liposomal bupivacaine (40 patients), spinal anesthesia with bupivacaine plus intrathecal morphine (41 patients) but no liposomal bupivacaine injection, or spinal anesthesia with bupivacaine (38 patients) and no liposomal bupivacaine injection. The two groups that did not receive periarticular liposomal bupivacaine did receive periarticular injection with ropivacaine, and all three groups had ketorolac (30 mg) plus epinephrine (1:1000) in the periarticular injections. Patients in all three groups received identical perioperative multimodal analgesic and antiemetic drugs. All patients were analyzed in the group to which they were randomized and no patients were lost to followup. The primary study endpoints were visual analog score (VAS) for pain and narcotic use during postoperative day 1. Secondary endpoints included side effects associated with narcotic administration during the hospital stay. RESULTS: Mean VAS pain in the liposomal bupivacaine PAI group was lower than that for the ropivacaine PAI group at 6 hours (1.8 ± 2.1 versus 3.3 ± 2.3, p = 0.005, mean difference: 1.5, 95% confidence interval [CI], 0.5-2.5) and 12 hours (1.5 ± 2.0 versus 3.3 ± 2.4, p < 0.001, mean difference: 1.8, 95% CI, 0.8-2.8) after surgery. The morphine spinal group had lower pain compared with the liposomal bupivacaine PAI group at 6 hours (0.9 ± 1.8 versus 1.8 ± 2.1, p = 0.035, mean difference: 1.0, 95% CI, 0.1-1.8), but there was no difference at 12 hours (0.8 ± 1.5 versus 1.5 ± 2.0, p = 0.086, mean difference: 0.7, 95% CI, -0.1 to 1.5). The magnitude of the differences at 6 and 12 hours are near the lower end of minimal clinically important differences reported in the literature, and thus the improvement shown in this study may only represent a small clinical improvement. Both the liposomal bupivacaine group (13% [five of 40]) and the ropivacaine group (5% [two of 38]) had fewer incidents of itching (pruritus) than the spinal morphine group (38% [15 of 41]) (p = 0.001). CONCLUSIONS: This prospective multicenter three-arm blind randomized controlled trial showed potentially improved pain control at 6 and 12 hours in the liposomal bupivacaine and intrathecal morphine groups compared with the ropivacaine group at the cost of much higher incidences of pruritus (itching) in the intrathecal morphine group. Based on these results, we prefer the use of PAI with liposomal bupivacaine as an alternative to spinal anesthesia with intrathecal morphine as a result of similar postoperative pain control and the potential for reducing adverse events. LEVEL OF EVIDENCE: Level I, therapeutic study.

Does a simple syringe applicator enhance bone cement set up time in knee arthroplasty?

BACKGROUND: The time required for polymethylmethacrylate (PMMA) cement curing or hardening can be modified by a number of variables including the mixing technique, and the temperature and pressure at which the process is taking place. Therefore, the purpose of this study was to evaluate two different methods of PMMA application in terms of set up time. Specifically, we (I) compared the PMMA set up time of cement that remained in the mixing bowl to cement that was placed in a syringe and (II) extrapolated the associated annual cost difference on the national and individual surgeon levels. METHODS: The cement set up time was measured for a total of 146 consecutive patients who underwent either unicompartmental knee arthroplasty (n=136) or patellofemoral arthroplasty (n=10) between January 2016 and April 2017. One pack of PMMA powder and monomer were mixed, placed in a 300 mL small plastic bowl, and mixed with a tongue depressor. Then, 50 mL of the mixed PMMA was placed in a sterile 60 mL syringe with the tip cut to a 6-mm opening, and the syringe was used to apply the cement to the bone and the prosthesis surface. The remaining unused cement in the syringe (syringe group) and the remaining unused cement in the plastic bowl (bowl group) were removed and formed into a two separate 2 cm diameter cubes that were allowed to cure at room temperature on a sterile set of osteotomes. The two cubes of cement were timed for complete PMMA curing. A two-tailed student's t-test was used to compare the curing time for the two groups. Annual cost differences were calculated on the national and individual surgeon level. The total number of daily cases performed and the operative time savings using the syringe applicator was used to find daily and annual cost savings. RESULTS: The mean time for the cement to set up in the bowl group was 16.8±2.1 minutes, and the mean time for cement set up in the syringe group was 15.1±1.7 minutes. Compared to the bowl group cement set up time, the syringe group set up time was significantly lower (P<0.0001). An estimated 350,000 cemented knee arthroplasties are performed each year in the United States. With 1.7 minutes saved per case, 595,000 operating room minutes per year could be saved, resulting in a nearly $71,000,000 national and $110,000 individual surgeon annual cost savings. CONCLUSIONS: The results of the present study demonstrated that the utilization of a simple, inexpensive syringe applicator enhanced the cement set up time by over one and a half minutes. This may be a result of the pressure differences in the syringe applicator. In addition to the control of and precision of where the cement is placed, the syringe applicator could provide an important potential time advantage to the arthroplasty surgeon.

Have the annual trends of total knee arthroplasty in ankylosing spondylitis patients decreased?

BACKGROUND: Ankylosing spondylitis (AS) is characterized by osteoproliferation-induced structural damage and spinal inflammation, which lead to spinal deformity and functional disability. Though AS commonly affects the axial skeleton and sacroiliac joints, up to 70% of patients have involvement of the knees and other joints. Despite pharmacological efforts, advancing joint involvement may ultimately require surgical intervention. Total knee arthroplasty (TKA) is effective in managing patients with AS, yet it remains unclear whether or not the annual rates of TKA have been affected. Therefore, the purpose of this study was to evaluate the annual trends of AS patients who underwent TKA. Specifically, we evaluated: (I) the annual trends of TKAs due to AS in the United States population; (II) the annual trends in the proportion of TKAs due to AS in the United States. METHODS: The Nationwide Inpatient Sample (NIS) was used to identify all patients who underwent TKA between 2002 and 2013 (n=6,492,873). Then, a subsequent query was performed to identify TKA patients who had a diagnosis of AS, defined by the International Classification of Disease 9th revision diagnosis code 720.0. The incidence of TKAs with a diagnosis of AS in the United States was calculated using the United States population as the denominator. Regression models were used to analyze the annual trends of AS in patients who underwent TKA. RESULTS: During the study period, 2,986 patients who had AS who underwent TKA were identified. The annual number of TKAs with a diagnosis of AS increased by 168% from 125 to 335. After normalizing to the US population, the incidence of TKAs with AS increased from 0.58 to 1.38 TKAs per million US adults [IRR =1.08 (95% CI: 1.07-1.09), P<0.001]. Out of the 350,122 TKAs in 2002, 125 (0.04%) were due to AS, whereas, out of the 640,695 TKAs in 2013, 335 (0.05%) were due to AS. The prevalence of AS in those who underwent TKA increased from 2002 to 2013 [coefficient =0.002 (95% CI: 0.001-0.003), P=0.004]. CONCLUSIONS: The annual trends of AS patients undergoing TKA significantly increased during the study period. To the authors' best knowledge, this is the first study to evaluate TKA trends in the AS population. The literature has reported on the ability of non-steroidal anti-inflammatory drugs (NSAIDs) and the potential of tumor necrosis factor-alpha (TNFα) inhibitors to hinder bone disease progression in AS, however, this was not shown to support to the significant changes found in TKA trends during the study period.

Are the anatomy textbooks wrong? A clinical patho-anatomic study of foveal vessels in the round ligament of the hip.

BACKGROUND: The foveal vessels of the ligamentum teres are an anterior branch of the posterior division of the obturator artery, providing blood to the capitis of the femoral head. However, the basic anatomic description of foveal vasculature in the ligamentum teres of the hip is widely variable, with some studies reporting that the vessels are not patent in roughly one third of all adults. Therefore, the purpose of this study was to evaluate the status of foveal vessels in primary total hip arthroplasty (THA) patients. Specifically, we evaluated: (I) if the foveal vessels were intact; and we (II) correlated foveal vessel status with (i) patient demographics, including gender and age; as well as (ii) perioperative data, such as operative time and blood loss. METHODS: The macroscopic status of the foveal vessels in the ligamentum teres femoris was documented in 266 patients at the time of primary unilateral THA performed between August 2015 and April 2017. The vessels were considered to be intact if active bleeding was directly visible from the acetabular stump of the severed ligamentum teres femoris. Demographics including age, gender, and preoperative diagnosis were collected. The perioperative outcome variables included estimated blood loss (EBL) and operative time. Foveal vessel status defined as intact or not intact, was also correlated with patient demographics and perioperative data. A student's t-test was used to compare the continuous variables and a chi square test was used for categorical variables. RESULTS: The foveal vessels were intact in 161 patients (61%) and not intact in 105 patients (39%). The mean age for patients with intact foveal vessels was found to be 64 years (range, 18 to 94 years) vs. 65 years (range, 29 to 94 years) (P>0.05) for not intact. No correlation was found between preoperative diagnosis, gender, operative time, and EBL and foveal vessel status. CONCLUSIONS: The results of this clinical patho-anatomic study of the foveal vessels in the ligamentum teres femoris of the hip refutes the polarized claims of prior anatomy texts that document the vessels as either "absent in adults" or "always intact." Rather, the results of this study reveal an alternate option: that foveal vessels can be present and either be intact (61%) or not intact (39%). No correlation was found between age, gender, operative time, and EBL and foveal vessel status.

Opioid-Sparing Pain Control in Outpatient Total Joint Arthroplasty.

Postoperative pain management is vital to promoting recovery and improving clinical outcomes. Although improved understanding of pain pathways has led to the development of varied approaches for controlling pain after surgery, some approaches are associated with potentially harmful side effects. Several lines of evidence have demonstrated that opioid analgesics can have unwanted adverse effects on patients having surgery. Similarly, risks associated with femoral nerve blocks have outweighed the benefits. Liposomal bupivacaine has shown efficacy in reducing the need for opioid analgesics and nerve blocks. Specifically, use of liposomal bupivacaine in a multimodal analgesia plan resulted in superior clinical and economic parameters in total joint arthroplasty. These advantages of liposomal bupivacaine are valuable in the current health care environment and in outpatient joint arthroplasty, in which highly effective opioid-sparing pain management is a prerequisite. Thus, liposomal bupivacaine can be used to reduce the burden of opioids and facilitate same-day discharge, thereby addressing some of the challenges associated with implementing short-stay or outpatient total joint arthroplasty.

Twenty-Five-Years and Greater, Results After Nonmodular Cemented Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) has been shown to be very successful with long-term follow-ups. But there are no reports showing prosthesis survival at 25-30 years. Here, we report the outcomes for 25-30 years using the Anatomic Graduated Component (Biomet, Warsaw, IN) TKA and elucidate the etiology and cause of failure of the components. METHODS: We reviewed the outcomes of 5649 primary total knee arthroplasties for 25-30 years using the Anatomic Graduated Component. Statistical analysis was performed by the Kaplan-Meier survival analysis. Clinical outcomes included the Knee Society Score and standardized radiographs to check for loosening of the implants. The reason for revision surgery was reviewed retrospectively. We compared our results with those at another institution with similar long-term follow-up. RESULTS: There were 112 failures, 48 with aseptic loosening and 25 with instability for an overall prosthesis survival rate of 94.2% at 25 years and 92.4% at 30 years follow-up. In the third decade after TKA, patients are substantially more likely to experience death than experience a failing prosthesis, with a 3811% greater risk of dying relative to failing (Risk ratio = 38.1, Odds ratio = 56.7, P < .0001). CONCLUSION: There was a greater risk of dying than failing over time. The primary reason for revision knee surgery was due to aseptic loosening of the prosthesis followed by instability.