Biologic Therapies for the Treatment of Knee Osteoarthritis.

BACKGROUND: The use of biologic therapies for the management of knee osteoarthritis has increased, despite insufficient evidence of efficacy. Our aim was to complete a systematic review and analysis of reports utilizing the highest level-of-evidence evaluating: (1) platelet-rich plasma injections (PRPs); (2) bone marrow-derived mesenchymal stem cells (BMSCs); (3) adipose-derived mesenchymal stem cells (ADSCs); and (4) amnion-derived mesenchymal stem cells (AMSCs). METHODS: PubMed, Embase, and Cochrane Library databases were queried for studies evaluating PRP injections, BMSCs, ADSCs, and AMSCs in patients with knee osteoarthritis. Of 1009 studies identified within the last 5 years, 123 met inclusion criteria. A comprehensive analysis of all levels-of-evidence was performed, as well as separate analysis on level-of-evidence I studies. Level-of-evidence was determined by the American Academy of Orthopedic Surgeons classification system. RESULTS: Although the majority of PRP reports demonstrated improvements in pain and/or function, others revealed no substantial improvements. Similar findings were noted for BMSCs, ADSCs, and AMSCs. Assessments of BMSC studies yielded majority with positive clinical results, although short-lived. Studies on ADSCs revealed improved clinical outcomes, but equivocal radiographic outcomes. Studies evaluating AMSCs demonstrated improvements in pain and function, and decreased radiographic evidence of osteoarthritis. CONCLUSION: Despite some promising early results for PRP, BMSC, ADSC, and AMSC therapies, the majority of level-of-evidence I studies have multiple problems: small sample sizes, potentially inappropriate control cohorts, short-term follow-up, and so on. Despite the limitations, there still appears to be evidence justifying their use for knee osteoarthritis management. More high-level, larger human studies utilizing standardized protocols are needed.

Treatment of Closed Femoral Shaft Fractures in Children Aged 6 to 10.

BACKGROUND: Management of pediatric femoral shaft fractures remains controversial, particularly in children between the ages of 6 and 10. In the current push toward cost containment, hospital type, and surgeon subspecialization have emerged as important factors influencing this treatment decision. Thus, in the present study, we use a nationwide pediatric inpatient database to compare the: (a) incidence; (b) demographic characteristics; (c) hospital costs; (d) length of stay; and (e) treatment method of pediatric closed femoral shaft fractures admitted to general versus children's hospitals. METHODS: The Kids' Inpatient Database (KID) was queried for all patients aged 6 to 10 who sustained a closed femoral shaft fracture in 2009 or 2012, and patient records were stratified into children's hospitals and general hospitals. Primary outcome measures included method of treatment, total hospital costs, and length of stay. Student/Welch t testing and χ analysis were utilized to compare continuous and categorical outcomes, respectively, between hospital types. RESULTS: The total incidence of closed femoral shaft fractures decreased between 2009 and 2012 (1919 to 1581 patients; P=0.020), as did the proportion of patients treated in children's hospitals (58.6% to 32.3%; P<0.001). In addition, patients treated at general hospitals were more likely to receive open reduction with internal fixation (45.3% vs. 41.1%) or external fixation (4.1% vs. 2.3%), and less likely to be managed with closed reduction with internal fixation (32.0% vs. 39.7%) than those treated at children's hospitals (P<0.001 for all). CONCLUSIONS: The present study demonstrates a decrease in the incidence of closed femoral shaft fractures in 6- to 10-year old patients from 2009 to 2012, as well as decreased definitive management in children's hospitals and increased selection of operative treatment. In addition, treatment in a nonchildren's hospital was associated with decreased total inpatient costs and decreased treatment with closed reduction with internal fixation in favor of open reduction with internal fixation. Future studies should seek to identify the specific surgical procedures performed and match patients more closely based specific fracture pattern. LEVEL OF EVIDENCE: Prognostic level II.

Primary Total Knee Arthroplasty Implants as Functional Prosthetic Spacers for Definitive Management of Periprosthetic Joint Infection: A Multicenter Study.

BACKGROUND: There are limited data on the utility of a standard primary total knee arthroplasty (TKA) femoral component with an all polyethylene tibia as a functional prosthetic spacer in place of a conventional all cement spacer for the management of periprosthetic joint infection (PJI). The aim of this multicenter study was to retrospectively review (1) ultimate treatment success; (2) reimplantation rates; (3) reoperation rates; and (4) change in knee range of motion in patients managed with functional prosthetic spacers following TKA PJI. METHODS: A retrospective review was performed for patients at 2 tertiary care centers who underwent a functional prosthetic spacer implantation as part of a functional single-stage (n = 57) or all cement spacer conventional two-stage (n = 137) revision arthroplasty protocol over a 5-year period. Outcomes including reinfection, reimplantation, and reoperation rates, success rate as defined by the Delphi criteria, and final range of motion were compared between the 2 cohorts at a minimum of 2-year follow-up. RESULTS: There was no significant difference in reinfection (14.0 vs 24.1%), reoperation (19.3 vs 27.7%), or success rates (78.9 vs 70.8%; P > .05 for all) between the one-stage and two-stage revision TKA cohorts. Mean final total arc of motion was also similar between the 2 groups (105.8 vs 101.8 degrees, respectively). CONCLUSION: Functional prosthetic spacers offer the advantage of a single procedure with decreased overall hospitalization and improved cost-effectiveness with analogous success rates (78.9%) compared with two-stage exchange (70.8%) at mid-term follow-up. Although long-term data are required to determine its longevity and efficacy, the outcomes in this study are encouraging. LEVEL OF EVIDENCE: 3.

Adjunctive Intravenous Diclofenac Decreases Opioid Consumption and Increases Satisfaction in the Primary Total Hip Arthroplasty Population.

Despite the success of total hip arthroplasty (THA), postoperative pain management remains a concern. Although the nonsteroidal anti-inflammatory drug (NSAID) intravenous (IV) diclofenac is a promising addition, its impact on THA outcomes has not been investigated. This study evaluates the effects of adjunctive IV diclofenac on: 1) postoperative pain intensity; 2) opioid consumption; 3) discharge destination; 4) length of stay; and 5) patient satisfaction in primary THA patients. A retrospective study was performed for patients who underwent primary THA by a single surgeon between May 1 and September 31, 2017. Patients of the study group (n=25) were treated postoperatively with IV diclofenac and the standard pain control regimen while the control group (n=88) did not receive diclofenac. Patients receiving adjunctive IV diclofenac were more likely to be discharged home than to inpatient facilities (O.R. 4.02; p=0.049). Patient satisfaction with respect to how well and how often pain was controlled (p= 0.0436 and p=0.0217, respectively) was significantly greater in the IV diclofenac group. Patients who received IV diclofenac had lower opioid consumption on postoperative days one and two (-67.2 and -129.0mg, respectively; p=0.001 for both). The growth of THA as an outpatient procedure has intensified the urgency of improving postoperative pain management. This study demonstrates that THA patients receiving adjunctive IV diclofenac were more likely to be discharged home, had reduced opioid consumption, and experienced greater satisfaction. To further investigate the optimal regimen, future studies comprising a larger cohort and comparing IV diclofenac to other NSAIDs are warranted.

Clostridium difficile infection in the USA: incidence and associated factors in revision total knee arthroplasty patients.

INTRODUCTION: Revision total knee arthroplasty (TKA) procedures performed secondary to periprosthetic joint infection (PJI) are associated with significant morbidity and mortality. These poor outcomes may be further complicated by postoperative infection requiring antibiotics. However, antibiotic overuse may suppress patients' bacterial flora, leading to Clostridium difficile infection (CDI). Therefore, we aimed to study the: (1) incidence; (2) costs; and (3) risk factors associated with CDI in revision TKA patients. METHODS: The National Inpatient Sample database was queried for individuals diagnosed with PJI who underwent revision TKA between 2009 and 2013 (n = 83,806). Patients who developed CDI during their inpatient stay were identified (n = 799). Logistic regression analysis was conducted to assess the association between hospital- and patient-specific characteristics and the development of CDI. RESULTS: The incidence of CDI after revision TKA was 1.0%. These patients were older (mean age 69.05 vs. 65.52 years), had greater LOS (median 11 vs. 5 days) and greater costs ($30,612.93 vs. 18,873.75), and experienced higher in-hospital mortality (3.6 vs. 0.5%; p < 0.001 for all) compared to those without infection. Patients with CDI were more likely to be treated in urban, not-for-profit, medium/large hospitals in the Northeast or Midwest (p < 0.05 for all) and to have underlying depression (OR 4.267; p = 0.007) or fluid/electrolyte disorders (OR 3.48; p = 0.001). CONCLUSION: Although CDI is rare following revision TKA, it can have detrimental consequences. We demonstrate that CDI is associated with longer LOS, higher costs, and greater in-hospital mortality. With increased legislative pressure to lower healthcare expenditures, it is crucial to identify means of preventing costly complications.

Risk Factors and Costs Associated With Clostridium difficile Colitis in Patients With Prosthetic Joint Infection Undergoing Revision Total Hip Arthroplasty.

BACKGROUND: With the increased demand for primary total hip arthroplasty (THA) and corresponding rise in revision procedures, it is imperative to understand the factors contributing to the development of Clostridium difficile colitis. We aimed to provide a detailed analysis of: (1) the incidence of; (2) the demographics, lengths of stay, and total costs for; and (3) the risk factors and mortality associated with the development of C. difficile colitis after revision THA. METHODS: The National Inpatient Sample database was queried for all individuals diagnosed with a periprosthetic joint infection and who underwent all-component revision THA between 2009 and 2013 (n = 40,876). Patients who developed C. difficile colitis during their inpatient hospital stay were identified. Multilevel logistic regression analysis was conducted to assess the association between hospital- and patient-specific characteristics and the development of C. difficile colitis. RESULTS: The overall incidence of C. difficile colitis after revision THA was 1.7%. These patients were significantly older (74 vs 65 years), had greater lengths of hospital stay (19 vs 9 days), accumulated greater costs ($51,641 vs $28,282), and were more often treated in an urban hospital compared to their counterparts who did not develop C. difficile colitis (P < .001 for all). Patients with colitis also had a significantly higher in-hospital mortality compared to those without (5.6% vs 1.4%; P < .001). CONCLUSION: While C. difficile colitis infection is an uncommon event following revision THA, it can have potentially devastating consequences. Our analysis demonstrates that this infection is associated with a longer hospital stay, higher costs, and greater in-hospital mortality.

Does the Amount of Opioid Consumed Influence How Patients Rate Their Experience of Care After Total Knee Arthroplasty?

BACKGROUND: With legislative efforts aimed at optimizing value of care, surgeons performing total knee arthroplasty (TKA) are faced with increased responsibility of optimizing patient perception of care. However, pain after TKA may negatively influence patient perception of care, as measured by Press Ganey (PG) patient satisfaction surveys. While opioid-based medications are best suited for acute pain alleviation, awareness of a growing opioid epidemic has spurred efforts to reduce its administration. Therefore, this study assessed the correlation between postoperative opioid consumption and 7 PG question domains: (1) overall hospital rating; (2) communication with nurses; (3) response time of hospital staff; (4) communication with doctors; (5) hospital environment; (6) pain management and; (7) communication about medication. METHODS: We reviewed our institutional PG database for TKA patients from 2011 to 2014. A total of 406 patients were analyzed (mean age = 66, 73.4%). Opioid consumption was measured using a morphine milliequivalent conversion algorithm. Bivariate correlation analysis assessed the association between opioid consumption and PG domains. Spearman's r was utilized to assess the strength of the association. RESULTS: No association between total opioid consumption and overall hospital rating (r = 0.044), communication with doctors (r = 0.080), communication with nurses (r = 0.072), responsiveness of hospital staff (r = 0.084), pain management (r = 0.100), communication about medicines (r = 0.083), or hospital environment (r = 0.155) were found. DISCUSSION: Our findings demonstrate that PG scores are not influenced by immediate postoperative opioid use. These results suggest opioid-based pain medications should be administered exclusively on the basis of clinical guidelines and patient needs without concern regarding satisfactions scores and reimbursement penalties.

Opioids Consumed in the Immediate Post-Operative Period Do Not Influence How Patients Rate Their Experience of Care After Total Hip Arthroplasty.

BACKGROUND: Patient perception of care, commonly measured with Press Ganey (PG) surveys, is an important metric used to determine hospital and provider reimbursement. However, post-operative pain following total hip arthroplasty (THA) may negatively affect patient satisfaction. As a result, over-administration of opioids may occur, even without marked evidence of pain. Therefore, this study evaluated whether opioid consumption in the immediate postoperative period bears any influence on satisfaction scores after THA. Specifically, this study assessed the correlation between post-operative opioid consumption and 7 PG domains: (1) Overall hospital rating; (2) Communication with nurses; (3) Responsiveness of hospital staff; (4) Communication with doctors; (5) Hospital environment; (6) Pain Management; and (7) Communication about medicines. METHODS: Our institutional PG database was reviewed for patients who received THA from 2011 to 2014. A total of 322 patients (mean age = 65 years; 61% female) were analyzed. Patient's opioid consumption was measured using a morphine milli-equivalent conversion algorithm. Bivariate correlation analysis assessed the association between opioid consumption and Press-Ganey survey elements. Pearson's r assessed the strength of the association. RESULTS: No correlation was found between total opioid consumption and Overall hospital rating (r = 0.004; P = .710), Communication with nurses (r = 0.093; P = .425), Responsiveness of hospital staff (r = 0.104; P = .381), Communication with doctors (r = 0.009; P = .940), Hospital environment (r = 0.081; P = .485), and Pain management (r = 0.075; P = .536). However, there was a positive correlation between total opioid consumption and "Communication about medicines" (r = 0.262; P = .043). CONCLUSIONS: Our report demonstrates that PG patient satisfaction scores are not influenced by post-operative opioid use, with the exception of PG domain, "Communication about medications." These results suggest that opioid medications should be administered based solely on patient requirements without concern about patient satisfaction survey results.

Patients With Major Depressive Disorder Experience Increased Perception of Pain and Opioid Consumption Following Total Joint Arthroplasty.

BACKGROUND: Pain in the immediate postoperative period following total joint arthroplasty is influenced by various patient factors, including major depressive disorder (MDD). Therefore, this study aimed to compare the patient perception of pain and opioid consumption between patients with and without MDD who received either a total knee arthroplasty (TKA) or total hip arthroplasty (THA). Specifically, we compared (1) pain intensity, (2) lengths of stay, (3) opioid consumption, and (4) patient perception of pain control. METHODS: We reviewed our institutional Press Ganey database to identify patients with a diagnosis of MDD who received a THA (n = 48) and TKA (n = 68) between 2012 and 2016. An independent samples t-test and chi-square analyses were conducted to assess continuous and categorical variables, respectively. Analysis of covariance assessed the effects of depression on postoperative pain intensity. Mixed-design analysis of variance assessed the difference in opioid consumption between groups. RESULTS: Patients with MDD who received THA or TKA demonstrated a higher mean pain intensity score when compared to those without MDD; however, this was not statistically different (235.6 vs 207.7; P = .264 and 214.8 vs 185.1; P = .055, respectively). Patients with MDD who received THA or TKA consumed more opioids when compared to those without MDD (P = .048 and P = .038, respectively). CONCLUSION: Patients with MDD undergoing total joint arthroplasty consume more opioids compared to their matched cohort during the immediate postoperative period. Identifying patient-specific factors, such as MDD, could help arthroplasty surgeons modulate patients' course of recovery. These findings warrant more cooperation between arthroplasty surgeons and primary care providers to optimize outcome.

Global Budget Revenue on a Single Institution's Costs and Outcomes in Patients Undergoing Total Hip Arthroplasty.

BACKGROUND: The state of Maryland was granted a waiver by the Center for Medicare and Medicaid Services to implement a Global Budget Revenue (GBR) reimbursement model. This study aims to compare (1) costs of inpatient hospital stays; (2) postacute care costs; (3) lengths of stay (LOS); and (4) discharge disposition who underwent primary total hip arthroplasty at a single Maryland-based orthopedic institution before and after the implementation of GBR. METHODS: The Maryland Center for Medicare and Medicaid Services database was queried to obtain all Medicare patients who underwent total hip arthroplasty at a single institution before and after the implementation of GBR. We compared the differences in costs for the following: inpatient care, the postacute care period, and readmissions. In addition, we evaluated differences in LOS, discharge disposition, and complication rates. RESULTS: There was a significant decrease in inpatient costs ($26,575 vs $23,712), an increase in mean home health costs ($627 vs 1608), and a decrease in mean durable medical equipment costs ($604 vs $82) and LOS (2.92 days vs 2.33 days). There was an increase in discharge to home rates (72.3% vs 78.9%) and a decrease in discharge to acute rehabilitation (4.3% vs 1.8%) CONCLUSION: Under the GBR model, our institution experienced significant cost savings during the inpatient and postacute care episodes. Thus, GBR may serve as a viable solution to reducing costs to Medicare for high-volume arthroplasty institutions with a large Medicare population. Multicentered studies are needed to verify our results.

Articulating Spacers as a Modified One-Stage Revision Total Knee Arthroplasty: A Preliminary Analysis.

INTRODUCTION: Periprosthetic joint infection (PJI) following primary total knee arthroplasty (TKA) is a challenging complication for surgeons and patients alike. Although two-stage revision arthroplasty remains the gold standard PJI management in the United States, one-stage revision has had success in many parts of Europe. The aim of this study was to retrospectively review: 1) ultimate treatment success; 2) necessary antibiotic duration; 3) change in knee range of motion (ROM); and 4) final Knee Society Scores (KSS) in a case series of patients managed with retention of articulating antibiotic spacers following PJI. MATERIALS AND METHODS: A retrospective review was performed on all patients treated for chronic PJI after primary TKA with retention of articulating antibiotic spacers at a minimum of one-year follow-up. Descriptive analysis was utilized to evaluate demographic characteristics, discharge destination, follow-up and antibiotic durations, Knee Society Score (KSS), and rates of treatment failure. Paired-Samples t-Tests were utilized to evaluate mean changes in flexion and extension between the preoperative and postoperative time periods. RESULTS: Our final cohort included 29 patients who were managed with articulating spacer retention at a mean follow-up of 16.8 (range, 12.0 to 23.1) months, with 21 patients (72.4%) medically unfit for multiple surgeons and eight patients (27.6%) satisfied with their function. Mean age was 61.3 (range, 41 to 85) years and mean Charlson Comorbidity Index (CCI) was 6.1 (mean, 0 to 12). The predominant infecting organism was Methicillin-Resistant Staphylococcus aureus (MRSA), which was involved in eight patients (27.6%). There was a significant increase in postoperative knee flexion (+14.7°; p<0.001) and no decrease in postoperative knee extension (+2.3°; p=0.361). Treatment success in our cohort was 79.3% (23 patients), with four patients (13.8%) having chronic wound drainage and two patients (6.9%) requiring multiple spacer exchanges. Sixteen patients (55.2%) were able to complete their antibiotic regimen, with the remaining patients unable to discontinue their antibiotics by latest clinic follow-up. DISCUSSION: One-stage exchange arthroplasty offers the advantage of a single procedure with analogous failure rates compared to two-stage exchange, decreases hospitalization, and improves cost-effectiveness, which is paramount in today's healthcare environment. To our knowledge, this is the first study in the United States to evaluate outcome scores, function, and success rate of a modified one-stage revision TKA technique. Although we are unable to make definitive conclusions based on the small sample size, the outcomes in this study are encouraging.

Use of Neuromuscular Electrical Stimulation During Physical Therapy May Reduce the Incidence of Arthrofibrosis After Total Knee Arthroplasty.

INTRODUCTION: Arthrofibrosis remains a major complication following total knee arthroplasty (TKA) that negatively impacts patient outcomes and exhausts healthcare resources. The use of neuromuscular electrical stimulation (NMES) has demonstrated the ability to facilitate quadriceps muscle recovery and reduce pain. Therefore, the purpose of this study was to compare TKA patients who received physical therapy (PT) and adjuvant NMES therapy versus physical therapy alone in terms of: 1) rates of manipulation under anesthesia (MUA) to treat arthrofibrosis; and 2) post-therapy range of motion (ROM). MATERIALS AND METHODS: This was a retrospective review of TKA patients from multiple institutions who underwent physical therapy versus physical therapy and adjuvant NMES therapy following primary TKA. A total of 206 patients were reviewed in the two cohorts that either received PT alone (n=86) or PT and adjuvant NMES therapy (n=120). Data regarding the requirement of MUA postoperatively for treatment of arthrofibrosis were collected for every patient. Additionally, pre- and post-therapy knee ROM data was also collected. Outcomes in both cohorts were then compared and analyzed. RESULTS: Lower rates of arthrofibrosis requiring MUA were recorded in patients who used NMES therapy and PT when compared to PT alone (7.5% vs. 19.8%; p=0.009). Log regression analysis revealed lower odds of needing MUA in patients who utilized NMES therapy in adjunct with PT (odds ratio [OR]=0.36; 95% CI: 0.115 to 0.875; p=0.023). Patients who received the NMES therapy were shown to have a statistically greater mean improvement in ROM when compared to those patients who did not receive NMES (+2.63, p=0.04). Log regression analysis also demonstrated that post-PT ROM decreased the odds of receiving MUA with a larger ROM (OR=92; 95% CI: 0.824 to 0.9855; p<0.001). CONCLUSION: This study demonstrated that the use of NMES during PT may reduce the incidence of arthrofibrosis and improve patient ROM. Prospective, randomized controlled, and larger-scale studies are needed to validate these results. Nevertheless, this novel report demonstrated the positive outcomes for a new application of the NMES therapy.

A Prospective, Randomized Trial Comparing Liposomal Bupivacaine vs Fascia Iliaca Compartment Block for Postoperative Pain Control in Total Hip Arthroplasty.

BACKGROUND: Increasing demand for total hip arthroplasty (THA) in a climate of increasing focus on clinical outcomes, patient satisfaction, and cost has created a need for better acute postoperative pain control for patients. An ideal pain control method would have few side effects, decreased opioid consumption, improved pain control, early ambulation, and decreased hospital length of stay (LOS). METHODS: We performed a prospective randomized, controlled study involving 79 patients undergoing elective THA between June 2015 and February 2016. Forty patients received liposomal bupivacaine and 39 patients received a fascia iliaca compartment block (FICB). In addition, the medical records of 28 patients who underwent elective THA between May 2015 and December 2015 were retrospectively examined. The primary outcome was visual analog scale pain scores and the secondary outcomes were LOS and total opioid consumption. SPSS, version 22, was used to run 1-way analysis of variance with contrast and Mood's median test on the data. RESULTS: There were statistically significant decreases in pain intensity (P = .019) and LOS (P = .041) in both the liposomal bupivacaine group and the FICB group compared with those in the retrospective control group. In addition, only the FICB group showed statistically significant decreased total opioid consumption compared with that in the retrospective group (P = .028). CONCLUSION: Patients undergoing elective THA have decreased overall pain intensity and a shorter LOS with multimodal pain management regimen that includes either liposomal bupivacaine or FICB. Patients who received FICB required less overall total opioids than the control group.

The Effect of Preoperative Physical Status on Pain Management in Total Knee Arthroplasty Patients Receiving Adductor Canal Blockade.

INTRODUCTION: Managing postoperative pain can be challenging for arthroplasty surgeons. While pain control modalities, such as adductor canal blockade (ACB), have been proven effective, the multifactorial nature of pain perception may serve as an obstacle for optimizing pain control. This study assesses the effect of patient pre-operative physical status on patient perception of pain. Specifically, we compared 1) lengths of hospital stay (LOS), 2) pain levels, and 3) opioid consumption in patients receiving total knee arthroplasty (TKA) who presented with an American Society of Anesthesiologists physical status score (ASA) of 2 and 3. MATERIALS AND METHODS: A single hospital, single surgeon database was reviewed for patients who had TKA between January 2015 and April 2016. Only patients with an ASA class of 2 or 3 who received ACB were analyzed. This yielded 106 patients with a mean age of 63 years, comprised of 36 men and 70 women. Patients were stratified into those with an ASA class of 2 (n= 58) and those with an ASA class of 3 (n= 48). Electronic medical records were reviewed to obtain demographic and endpoint data. Pain was quantified using Visual Analog Scale (VAS). Continuous variables were compared using the student' s t-test and analysis of variance, while categorical variables were compared using chi-square analysis. RESULTS: There was no significant difference found between the two groups in LOS (2.25 days vs. 2.19 days; p=0.805), VAS scores (4.95 vs. 5.75; p=0.306), and opioid consumption on day 0 (17.77 morphine eq vs. 23.49 morphine eq; p=0.233) and day 3 (9.11 morphine eq vs. 19.87 morphine eq; p=0.100). However, patients with an ASA score of 2 had a significantly lower opioid consumption on day 1 (32.20 morphine eq vs. 52.70 morphine eq; p=0.049), day 2 (19.21 morphine eq vs. 40.71 morphine eq; p=0.018), and overall (78.30 morphine eq vs. 135.77 morphine eq; p=0.024). CONCLUSION: Despite the effectiveness of ACB in controlling pain, patient pre-operative status may affect perception of pain. This study demonstrates that patients with a higher ASA physical status classification consumed more opioid medication postoperatively, despite having similar pain scores and lengths of stay to those with a lower classification. Future studies should assess all ASA classifications and stratify for preoperative opioid consumption and tolerance as a possible confounder.

The Addition of Diclofenac to a Multimodal Pain Control Regimen Decreases Postoperative Pain and Opioid Consumption.

INTRODUCTION: Total knee arthroplasty (TKA) is a commonly-performed orthopaedic procedure in the United States. However, inadequate postoperative pain management following TKA has been associated with a number of negative consequences, including chronic postoperative pain requiring long-term opioid use. Multimodal pain control is a recently-popularized means of maximizing analgesia and postoperative outcomes. We aimed to evaluate the outcomes of a multimodal pain regimen incorporating diclofenac, including: 1) length of stay (LOS); 2) pain intensity; and 3) opioid consumption in primary TKA patients. MATERIALS AND METHODS: A prospective cohort study was performed. All patients scheduled for primary TKA by a single surgeon between March 1, 2017 and August 31, 2017 were screened for study involvement, yielding 46 consecutive patients (52 TKAs). This study group was treated with a postoperative regimen of intravenous (IV) diclofenac, in addition to a perioperative pain control regimen including adductor canal blockade (ACB) and periarticular multimodal drug injection (PMDI). Postoperative outcomes in this group were compared to those of a matched cohort of 78 patients (88 primary TKAs) who had previously been treated with the same perioperative pain control regimen. RESULTS: Patients prescribed a postoperative diclofenac regimen had lower mean LOS (2.10 vs. 2.33 days; p=0.053) and lower 24-hour postoperative pain intensity (76 vs. 104; p=0.056) as compared to the untreated group. The diclofenac-treated group had a significantly lower opioid consumption in the first 24 hours postoperatively than did their untreated counterparts (39.8 vs. 53.1 morphine milligram equivalents [MME]; p=0.041). In addition, 17 patients (18 TKAs, 35%) in the diclofenac group had zero opioid requirements during the first 12 hours postoperatively, and 12 of these patients (13 TKAs, 25%) continued to not require any opioids through the first 24 hours postoperatively. DISCUSSION: In the midst of the rapidly-increasing rates of TKA in the US, multimodal pain control has emerged as an extremely effective means of maximizing postoperative patient outcomes. To our knowledge, this is the first study to evaluate the postoperative outcomes of TKA patients treated with a regimen of IV diclofenac. We demonstrate shorter LOS, decreased 24-hour pain intensity, and significantly decreased 24-hour opioid consumption in patients treated with adjunctive IV diclofenac compared to patients managed with our institution's standard perioperative regimen.

Acute Kidney Injury after Total Knee Arthroplasty: A Clinical Review.

INTRODUCTION: Patients who develop acute kidney injury (AKI) have an increased risk for progression to chronic kidney disease, end-stage renal disease, and increased mortality. The outcomes of total knee arthroplasty (TKA) patients who develop AKI have remained controversial. The purpose of this review was to summarize and identify the current literature focused on 1) major risk factors, 2) short-term outcomes, and 3) costs associated with the development of perioperative AKI after TKA. MATERIALS AND METHODS: A literature search was performed using PubMed and Ovid to find literature relevant to AKI in TKA. All abstracts found via literature search were screened for relevancy to the study topics: (1) risk factors, (2) short-term outcomes, and (3) cost. RESULTS: A total of 447 abstracts were initially identified. Irrelevant abstracts and those not in English were excluded from the study (n=336). Forty-five papers focused on risk factors associated with AKI, six papers focused on short-term outcomes, and seven discussed cost savings. Increased body mass index, metabolic syndrome, perioperative antibiotics, antihypertensive medications, and antibiotic-impregnated cement spacers are amongst the many modifiable patient and drug-induced risk factors associated with AKI after TKA. Perioperative renal injury is associated with increased inpatient and long-term mortality with increased length of stay and extended care facility discharge. CONCLUSION: Increased length of stay and comorbidities have shown higher cost utilization and readmission rates. Inpatient and long-term complications and mortality are associated with postoperative AKI and a multidisciplinary perioperative approach is necessary to appropriately identify and, ultimately, prevent patients at higher risk for acute renal failure.

Presentation of Knee Osteoarthritis in the Emergency Department: A Problem Worth Mentioning?

INTRODUCTION: Osteoarthritis (OA) of the knee is a progressive debilitating disease affecting more than 27 million Americans. Treatment is often aimed at reducing pain and slowing disease progression. However, patients with significant barriers to healthcare may elect to visit the emergency department (ED) due to OA-related knee pain. The purpose of this study is to provide a detailed analysis of 1) patient demographics; 2) payor type; 3) charges; and 4) discharge status of patients presenting to the emergency department with a primary diagnosis of knee OA. MATERIALS AND METHODS: The Nationwide Emergency Department Sample from 2009 to 2013 was queried for all patients who presented to the ED with a primary diagnosis of knee OA (ICD-9 CM=715.96) and did not have a concomitant major injury. This yielded 215,253 patients. An analysis of variance (ANOVA) test with a post-hoc Turkey-Kramer test was conducted to assess mean differences of continuous data over time. All categorical data was analyzed using chi-square analysis. RESULTS: The incidence of ED visits dropped significantly between the years 2009 and 2010 (68,661 to 36,846) and plateaued between the years 2010 and 2013. Patients had a mean age of 59.9 years and were primarily women (67.3%). The majority of patients were at the lowest 50% income bracket (68.8%). The Southern US census region had the highest number of ED visits (n=91,995; 42.7%), and Medicare was the primary payor in most cases (n=87,323; 40.7%). The mean charge for ED visits from 2009 to 2013 was $1,368.39, and there was a statistically significant increase in ED-related charges between 2009 and 2013 (p<0.001). The majority of discharges from the ED were routine (n=202,247; 93.8%). CONCLUSION: While the early management of knee osteoarthritis is largely successful at delaying the need for surgery, there are still many patients who do not receive adequate care and present to the emergency room for non-emergent evaluation. This, along with rising charges for ED visits, is likely increasing resource consumption and the financial impact on the healthcare system. Future efforts should focus on improving access to care for patients with knee OA before it develops into an overwhelming burden.

Impact of Neuromuscular Electrical Stimulation (NMES) on 90-Day Episode Costs and Post-Acute Care Utilization in Total Knee Replacement Patients with Disuse Atrophy.

INTRODUCTION: This study evaluated differences in: 1) total episode payments, 2) probability of hospital readmission, 3) probability of inpatient rehab facility (IRF) and utilization, and 4) probability of skilled nursing care facility (SNF) utilization in patients who had disuse atrophy and underwent a total knee arthroplasty (TKA) and either did, or did not, receive preoperative home-based neuromuscular electrical stimulation (NMES) therapy. MATERIALS AND METHODS: We used the Medicare limited dataset for a 5% sample of beneficiaries from 2014 and 2015 to construct episodes-of-care for TKA (DRG-470) patients with disuse atrophy who underwent a TKA during the 30 days prior to hospital admission and 90 days post-discharge. Patients were stratified into those who either did or did not receive pre- and postoperative NMES therapy. An ordinary least square (OLS) model was used to estimate the impact of NMES on total episode. Linear probability models were used to estimate the impact of NMES on SNF or IRF utilization and readmission. RESULTS: A $3,274 reduction in episode payments for patients who used preoperative NMES versus those who did not (p<0.001) was demonstrated. The probability of readmission was 12.7% lower for those who used preoperative NMES therapy versus those who did not (p=0.609). The probability of utilizing IRF and SNF was 56.7% (p=0.061) and 46.4% (p=<0.001) lower for those who used pre- and postoperative NMES versus those who did not, respectively. CONCLUSION: Significant reduction in total episode payments and SNF utilization for TKA patients with disuse atrophy who had NMES therapy was demonstrated.