Male Youth Ice Hockey Concussion Incidence in a USA Hockey Membership-Adjusted Population: A Peak in 2011 and the Impact of Major Rule Changes.

OBJECTIVE: To investigate the incidence of youth ice hockey-related concussions preceding and following the implementation of new body-checking and head contact rules by USA hockey in 2011. We hypothesized a decrease in concussions after the rule change. DESIGN: Retrospective analysis. SETTING: United States emergency department (ED) data queried in the National Electronic InjurySurveillance System (NEISS). PATIENTS: National Electronic Injury Surveillance System reported male youth (≤18 years) ice hockey concussion cases from January 1, 2002, to December 31, 2016. In total, 848 players were diagnosed with concussion, representing a national estimate of 17 374 cases. INDEPENDENT VARIABLES: Time, specifically years. MAIN OUTCOME MEASURES: Incidences and incidence rates (measured per 10 000 person-years) of male youth ice hockey concussions. Annual trends were analyzed using descriptive and linear or polynomial regression analysis. RESULTS: The national estimate of youth ice hockey-related concussions seen in US emergency departments (EDs) increased significantly from 656 in 2007 to 2042 in 2011 (P < 0.01). During the same period, their respective incidence increased significantly from 21.8 to 66.8 per 10 000, before dropping through 2016 (P < 0.05). After 2011, concussions decreased from 1965 in 2012 to 1292 in 2016 (P = 0.055). The gap in concussion incidence between the 11 to 12 and 13 to 14 divisions widened after 2011 (before 2011: 41 vs 49 per 10 000 person-years [P = 0.80]; after 2011: 45 and 89, respectively [P < 0.01]). CONCLUSIONS: US EDs experienced a significant increase in youth ice hockey concussion visits from 2007 to 2011. After the 2011 rule changes, concussion visits decreased significantly from 2012 to 2016.

Trends and epidemiology of radial head subluxation in the United States from 2004 to 2018.

BACKGROUND: Increased body mass may predispose children to a greater risk for radial head subluxation (RHS). Recent studies in the literature have reported a plateau in obesity prevalence among infants and toddlers. This study sought to examine recent epidemiological trends in RHS incidence from 2004 to 2018 using the National Electronic Injury Surveillance System database to determine how obesity patterns may affect RHS incidence. METHODS: The National Electronic Injury Surveillance System (NEISS) database was queried for patients 6 years of age or younger presenting with radial head subluxation between January 1, 2004 and December 31, 2018. Patient demographics, mechanisms of injury, and location of injury were recorded. RESULTS: An estimated total 253,578 children 6 years or younger were treated for RHS with 14,204 (95% CI = 8124-20,284) in 2004 to 21,408 (95% CI = 12,882-29,934) in 2018. The overall annual rate of RHS per 10,000 children ≤ 6 years was 6.03 (95% CI = 4.85-7.58). The annual rate of RHS per 10,000 children ≤ 6 years increased (m = 0.200, ß = 0.802, p < 0.001) from 5.18 (95% CI 2.96-7.39) in 2004 to 7.69 (95% CI = 4.63-10.75) in 2018. The most common mechanism associated with RHS was falls (39.4%) with 103,466 (95% CI 74,806-132,125) cases. Pulls accounted for the second most common mechanism of injury, accounting for 90,146 (95% CI 68,274-112,018) cases or 36.2%. Yearly RHS incidence was compared to obesity prevalence for ages 2-5 children provided by the National Health and Nutritional Examination Survey (NHANES) surveys. Changes in obesity prevalence may visually reflect RHS incidence trends, but no causality between obesity prevalence and RHS incidence could be confirmed. CONCLUSION: This study corroborated previous findings that falls and arm pulling contribute to the vast majority of RHS cases. The nonsignificant rise in RHS cases may reflect a possible plateau in obesity prevalence of children aged 2-5 years in recent years. LEVEL OF EVIDENCE: III.

Ankle Fracture Epidemiology in the United States: Patient-Related Trends and Mechanisms of Injury.

Current nationwide epidemiological data regarding ankle fractures are scarce. Such information is important towards better quantifying the mortality associated with such injuries, financial impact, as well as the implementation of preventative measures. This study evaluated the epidemiology of ankle fractures that occurred during a 5-year period. Specifically, we evaluated demographics, mechanism of injury, and disposition. The National Electronic Injury Surveillance System was queried to identify all patients with ankle fractures that presented to US hospital emergency departments between 2012 and 2016. Census data were used to determine the incidence rates of ankle fractures in terms of age, sex, and race. There was an estimated total of 673,214 ankle fractures that occurred during this period, with an incidence rate of 4.22/10,000 person-years. The mean age of patients with an ankle fracture was 37 ± 22.86 (SD) years; 23.5% of ankle fractures occurred in patients aged 10 to 19 years (7.56/10,000 person-years). In addition, 44% of ankle fractures occurred in men (3.81/10,000 person-years), whereas 56% occurred in women (4.63/10,000 person-years). Data on race/ethnicity were available for 71% of the subjects, with incidence rates of 2.85/10,000 person-years for whites, 3.01/10,000 person-years for blacks, and 4.08/10,000 person-years for others. The most common mechanism of injury was falls (54.83%), followed by sports (20.76%), exercise (16.84%), jumping (4.42%), trauma (2.84%), and other (0.30%). For disposition, 81.84% of patients were treated and released, 1.43% were transferred, 16.01% were admitted, 0.59% were held for observation, and 0.13% left against medical advice. The highest incidence of ankle fractures in men occurred in the 10-to-19-years age group, but women were more commonly affected in all other age groups.

Parkinson's disease increases the risk of perioperative complications after total knee arthroplasty: a nationwide database study.

PURPOSE: Therefore, the purpose of this study was to evaluate the short-term perioperative outcomes of PD patients who underwent total knee arthroplasty (TKA). We specifically evaluated: (1) perioperative surgical and medical complications; (2) lengths of stay (LOS); and (3) total hospital charges. METHODS: The Nationwide Inpatient Sample was used to identify PD patients who underwent TKA between 2002 and 2013. To control for potential confounders, PD TKA and non-PD TKA patients were propensity score matched (1:3) based on age, sex, ethnicity, Charlson Comorbidity Index, and insurance type. A total of 31,979 PD and 95,596 non-PD TKA patients were included. RESULTS: PD patients had a 44% higher risk of suffering from any complication (OR 1.44; 95% CI 1.35-1.54), a 45% increased risk for any medical complication (OR 1.45; 95% CI 1.36-1.55), and a 9% higher risk for any surgical complication (OR 1.09; 95% CI 0.84-1.41). Compared to the matched cohort, PD patients had a mean LOS that was 6.5% longer (95% CI 5.46-7.54) and mean total hospital charges that were 3.05% higher (95% CI 1.99-4.11). CONCLUSIONS: PD patients are more likely to have postoperative complications, longer LOS, and higher costs after TKA than non-PD TKA patients. Since many of these complications can be prevented, a team-based multi-specialty patient optimization is needed. LEVEL OF EVIDENCE: Level III, therapeutic study.

Use of Closed Incisional Negative Pressure Wound Therapy After Revision Total Hip and Knee Arthroplasty in Patients at High Risk for Infection: A Prospective, Randomized Clinical Trial.

BACKGROUND: Continuous wound drainage after arthroplasty can lead to the development of a periprosthetic joint infection. Closed incisional negative pressure wound therapy (ciNPWT) has been reported to help alleviate drainage and other wound complications. The purpose of this prospective randomized controlled trial is to compare the use of ciNPWT with our standard of care dressing in revision arthroplasty patients who were at high risk to develop wound complications. METHODS: A total of 160 patients undergoing elective revision arthroplasty were prospectively randomized to receive either ciNPWT or a silver-impregnated occlusive dressing after surgery in a single institution. Patients were included if they had at least 1 risk factor for developing wound complication(s): wound complication, readmission, and reoperation rates were collected at 2, 4, and 12 weeks postoperatively. RESULTS: The postoperative wound complication rate was significantly higher in the control cohort compared to the ciNPWT cohort (19 [23.8%] vs 8 [10.1%], P = .022). There was no significant difference between the control and ciNPWT cohorts in terms of readmissions (19 [23.8%] vs 16 [20.3%], P = .595). Reoperation rate was higher in controls compared to ciNPWT patients (10 [12.5%] vs 2 [2.5%], P = .017). After adjusting for the history of a prior periprosthetic joint infection and inflammatory arthritis, the ciNPWT cohort had a significantly decreased wound complication rate (odds ratio 0.28, 95% confidence interval 0.11-0.68). CONCLUSION: ciNPWT may decrease the rate of postoperative wound complications in patients who are at an increased risk of such wound issues after revision arthroplasty.

Comparison of a Posterior versus Anterior Approach for Lumbar Interbody Fusion Surgery Based on Relative Value Units.

INTRODUCTION: The current value-driven healthcare system encourages physicians to continuously optimize the value of the services they provide. Relative value units (RVUs) serve as the basis of a reimbursement model linking the concept that as the effort and value of services provided to patient's increases, physician reimbursement should increase proportionately. Spine surgery is particularly affected by these factors as there are multiple ways to achieve similar outcomes, some of which require more time, effort, and risk. Specifically, as the trend of spinal interbody fusion has increased over the past decade, the optimal approach to use-posterior versus anterior lumbar interbody fusion (PLIF vs. ALIF)-has been a source of controversy. Due to potential discrepancies in effort, one factor to consider is the correlation between RVUs and the time needed to perform a procedure. Therefore, the purpose of this study was to compare: 1) mean RVUs; 2) mean operative time; and 3) mean RVUs per unit of time between PLIF and ALIF with the utilization of a national surgical database. We also performed an individual surgeon cost benefit analysis for performing PLIF versus ALIF. MATERIALS AND METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was utilized to identify 6,834 patients who underwent PLIF (CPT code: 22630) and 6,985 patients who underwent ALIF (CPT code: 22558) between 2008 and 2015. The mean operative times (in minutes), mean RVUs, and RVUs per minute were calculated and compared using the Student's t-tests. In addition, the reimbursement amount (in dollars) per minute, case, day, and year for an individual surgeon performing PLIF versus ALIF were also calculated and compared. A p-value of less than 0.05 was used as the threshold for statistical significance. RESULTS: Compared to ALIF cases, PLIF cases had longer mean operative times (203 vs. 212 minutes, p<0.001). However, PLIF cases were assigned lower mean RVUs than ALIF cases (22.08 vs. 23.52, p<0.001). Furthermore, PLIF had a lower mean RVU/minutes than ALIF cases (0.126 vs. 0.154, p<0.001). The reimbursement amounts calculated for PLIF versus ALIF were: $4.52 versus $5.53 per minute, $958.66 versus $1,121.95 per case, and $2,875.98 versus $3,365.86 per day. The annual cost difference was $78,380.92. CONCLUSION: The data from this study indicates a potentially greater annual compensation of nearly $80,000 for performing ALIF as opposed to PLIF due to a higher "hourly rate" for ALIF as is noted by the significantly greater RVU per minute (0.154 vs. 0.126 RVU/minutes). These results can be used by spine surgeons to design more appropriate compensation effective practices while still providing quality care.

Perioperative Outcomes and Complications in Patients With Heart Failure Following Total Knee Arthroplasty.

BACKGROUND: Heart failure (HF) is a common comorbidity in the aging population and they will require major elective surgery. The purpose of this study is to determine if HF is a risk factor for adverse perioperative outcomes and short-term complications following total knee arthroplasty. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was utilized to identify all patients who underwent total knee arthroplasty for osteoarthritis from 2008 to 2014. Any diagnosis other than osteoarthritis was excluded. A total of 111,634 patients were identified and 251 of these patients had a preoperative diagnosis of HF. The main outcomes included operative time, lengths-of-stay, discharge disposition, return to operating room, readmission, and short-term complications, including death. RESULTS: Patients with HF were found to have longer hospital stays (ß = 0.59, 95% confidence interval [CI] 0.12-1.06) following total knee arthroplasty, and were more likely to return to the operating room (odds ratio 2.00, 95% CI 1.01-3.94) and be readmitted (OR 1.88, 95% CI 1.21-2.94). In addition, HF was found to be a risk factor for 1 or more complications (OR 1.41, 95% CI 1.05-1.90), wound dehiscence (OR 4.86, 95% CI 1.68-14.03), and myocardial infarction (OR 4.81, 95% CI 1.90-12.16) postoperatively. CONCLUSION: Patients with HF are more likely to have a longer length-of-stay, return to the operating room, and be readmitted. Additionally, they have a higher risk for at least one postoperative complication, myocardial infarction, and wound dehiscence.

Does Parkinson Disease Increase the Risk of Perioperative Complications After Total Hip Arthroplasty? A Nationwide Database Study.

BACKGROUND: Parkinson disease (PD) is the second most common neurodegenerative disorder in the United States, affecting over 1 million people. As part of the disease process, PD can cause poor bone quality and other musculoskeletal problems that can affect a patient's quality of life. With advances in treatment, PD patients can be more active and may be candidates for total hip arthroplasty (THA). However, there is a paucity of literature on the outcomes of THA in PD patients. Therefore, the purpose of this study was to evaluate the perioperative outcomes of PD patients who underwent THA. Specifically, we assessed: (1) perioperative surgical and medical complications; (2) lengths of stay (LOSs); and (3) total hospital charges. METHODS: Using the Nationwide Inpatient Sample, patients who had PD and underwent THA between 2002 and 2013 were identified. With the use of propensity scores, PD patients were matched in a 1:3 ratio to patients without PD by the year of surgery, age, gender, race, Charlson/Deyo score, and insurance type. This yielded a total of 10,519 PD and 31,679 non-PD THA patients. Regression analyses were used to compare the risk of perioperative complications (any, surgical, medical), the percent differences in mean LOS, and the percent differences in total hospital charges. RESULTS: Compared with the matched cohort, PD patients had a 52% higher risk for any complication (odds ratio [OR] = 1.52; 95% confidence interval [CI], 1.37-1.69), a 30% higher risk for any surgical complication (OR = 1.30; 95% CI: 0.88-1.91), and a 54% higher risk for any medical complication (OR = 1.54; 95% CI, 1.38-1.71). Specifically, PD patients were more likely to have postoperative delirium (OR = 2.61; 95% CI: 1.77-3.85), altered mental status (OR = 3.01; 95% CI: 1.35-6.71), urinary tract infection (OR = 1.34; 95% CI: 1.09-1.76), and blood transfusion (OR = 1.62; 95% CI: 1.44-1.82). Also, PD patients had a mean LOS that was 8.57% longer (P < .0001), and mean total hospital charges that were 3.85% higher (P < .0001). CONCLUSION: Orthopedic surgeons and neurologists should be involved in the preoperative counseling of PD patients regarding their potential increased risks associated with THA, which could help optimize their preoperative care. Furthermore, the risk of complications and higher costs could potentially lead to the development of different reimbursement methods in this population of patients.

Are We Appropriately Compensated by Relative Value Units for Primary vs Revision Total Hip Arthroplasty?

BACKGROUND: Relative value units (RVUs) are used to evaluate the effort required for providing a service to patients in order to determine compensation. Thus, more complicated cases, like revision arthroplasty cases, should yield a greater compensation. However, there are limited data comparing RVUs to the time required to complete the service. Therefore, the purpose of this study is to compare the (1) mean RVUs, (2) mean operative times, and (3) mean RVU/minute between primary and revision total hip arthroplasty (THA) and (4) perform an individualized idealized surgeon annual cost difference analysis. METHODS: A total of 103,702 patients who underwent primary (current procedural terminology code 27130) and 7273 patients who underwent revision THA (current procedural terminology code 27134) were identified using the National Surgical Quality Improvement Program database. Mean RVUs, operative times (minutes), and RVU/minute were calculated and compared using Student t-test. Dollar amount per minute, per case, per day, and year was calculated to find an individualized idealized surgeon annual cost difference. RESULTS: The mean RVU was 21.24 ± 0.53 (range, 20.72-21.79) for primary and 30.27 ± 0.03 (range, 30.13-30.28) for revision THA (P < .001). The mean operative time for primary THA was 94 ± 38 minutes (range, 30-480 minutes) and 152 ± 75 minutes (range, 30-475 minutes) for revision THA (P < .001). The mean RVU/minute was 0.260 ± 0.10 (range, 0.04-0.73) for primary and 0.249 ± 0.12 (range, 0.06-1.0) for revision cases (P < .001). The dollar amounts calculated for primary vs revision THA were as follows: per minute ($9.33 vs $8.93), per case ($877.12 vs $1358.32), per day ($6139.84 vs $5433.26), and a projected $113,052.28 annual cost difference for an individual surgeon. CONCLUSION: Maximizing the RVU/minute provides the greatest "hourly rate." The RVU/minute for primary (0.260) being significantly greater than revision THA (0.249) and an annualized $113,052.28 cost difference reveal that although revision THAs are more complex cases requiring longer operative time, greater technical skill, and aftercare, compensation per time is not greater.

Changes in Antibiotic Susceptibility of Staphylococcus aureus Between the Stages of 2-Stage Revision Arthroplasty.

BACKGROUND: Staphylococcus aureus is the predominant cause of periprosthetic joint infection (PJI) and can persist at the time of planned second stage of 2-stage revision arthroplasty, despite antibiotic cement spacer insertion and parenteral antibiotic therapy. Given the rapid emergence of antibiotic resistance, it is important to determine whether the antibiotic susceptibility of microorganisms changes between the stages of a 2-stage revision. METHODS: A total of 1614 2-stage revision hip/knee arthroplasties performed for PJI at 2 academic institutions from 2000 to 2015 were identified. S aureus (methicillin susceptible and/or resistant) was isolated by culture in 402 (24.9%) cases during the first stage (resection arthroplasty). S aureus persisted and was cultured in 30 cases (knees = 18, hips = 12) during the second stage. Minimum inhibitory concentrations (MICs), demographics, antibiotic therapy, and surgical history were collected. The MICs at the time of the first-stage and second-stage surgeries were compared. RESULTS: Nine (30%) revisions had an increase in vancomycin MIC. Six had an increase from ≤0.5 to 1 µg/mL, 2 had an increase from ≤0.5 to 2 µg/mL, and 1 had an increase from 1 to 2 µg/mL. All of the 9 revisions with an increase in vancomycin MIC had vancomycin in spacer. CONCLUSION: Increases in the MICs were observed for vancomycin, the antibiotic widely used in cement spacers, in about one-third of the revisions. Despite the small sample size, the data from this preliminary study raise concern about the potential for emergence of resistant organisms between the stages of a 2-stage revision.

A Comparison of Relative Value Units in Primary Versus Revision Total Knee Arthroplasty.

BACKGROUND: In total knee arthroplasty (TKA), revision cases are often technically more challenging, and require more operative time and aftercare than primary cases. These time and effort differences should therefore be appropriately compensated for when using the relative value unit (RVU) system. Therefore, the purpose of this study is to compare the mean (1) RVUs; (2) operative times; and (3) RVU/min; and (4) perform an individualized idealized surgeon annual cost difference analysis for primary vs revision TKA. METHODS: Current Procedural Terminology code 27447 identified 165,439 primary TKA patients, while Current Procedural Terminology code 27487 identified 8081 revision TKA patients from the National Surgical Quality Improvement Program database. The mean RVUs, operative times, and RVU/min were calculated. Dollar amount per minute, per case, per day, and year were also calculated. Student's t-test, with a cut-off P-value of <.05, was used in order to identify any statistical differences in mean RVUs, operative times, and RVU/min. RESULTS: The mean RVUs for primary TKA was 22, while for revision TKA was 27 (P < .001). The mean operative time for primary TKA was 94 minutes, while for revision TKA was 149 minutes (P < .001). The mean RVU/min for primary TKA was 0.26, while for revision TKA was 0.22 (P < .001). The dollar amounts calculated for primary vs revision TKA were per minute ($9.33 vs $7.90), per case ($877.12 vs $1176.43), per day ($4385.60 vs $3529), and projected a $137,008.70 annual cost difference. CONCLUSION: Orthopedic surgeons are reimbursed at a higher rate per minute for primary cases compared to revision TKA (0.26 vs 0.22, P < .001). The annual difference can amount to nearly $140,000. Orthopedic surgeons can use this information to better understand the dynamics of their time, compensation, and ultimately, their practice. Furthermore, it can be argued that there needs to be a shift to increase the RVU per unit time for revision TKAs.

Impact of Perioperative HbA1c on Reimbursements in Diabetes Mellitus Patients Undergoing Total Hip Arthroplasty: A Nationwide Analysis.

BACKGROUND: Patients who have diabetes mellitus (DM) are at an increased risk of postoperative complications following total hip arthroplasty (THA). Therefore, much interest has been paid to perioperative glycemic control. However, no prior studies have evaluated the patient variation of HbA1c levels on costs. Therefore, the purpose of this study was to evaluate the impact of obtaining preoperative HbA1c levels on (1) day of surgery (DOS) cost; (2) subsequent 89-day costs; and (3) global 90-day cost. METHODS: A retrospective query of the Humana insurance claims database was performed from 2007 to 2015 for all DM patients undergoing THA. Only patients with HbA1c (%) levels within 3 months before or after the THA were included. Patients were stratified into 6 groups based on HbA1c starting at 5.5% and increasing by 1% increments to 11.5%; one additional group (11.5%-20%) for extreme cases was analyzed. Correlations between HbA1c level and reimbursements for DOS, subsequent 89-day, and global 90-day period were performed. RESULTS: HbA1c level demonstrated a significant correlation to DOS (correlation coefficient = 0.664), subsequent 89-day (correlation coefficient = 0.789), and global 90-day period (correlation coefficient = 0.747) costs. DOS, 89-day, and global 90-day costs significantly increased with increasing HbA1c levels (P < .0001). CONCLUSION: Higher perioperative HbA1c levels increase the DOS, subsequent 89-day, and global 90-day costs of THA. This was expected as these patients require multidisciplinary care, have longer LOS, and develop more complications. Further investigation into postoperative complications based on glycemic control is warranted.

Linear Wear Rates of a Highly Cross-Linked Polyethylene Hip Liner.

INTRODUCTION: To help limit wear, newer polyethylene liners, such as the highly cross-linked polyethylene (HXLPE) liners, have been developed. These newer liners undergo an alternating irradiation process, resulting in a stronger, longer-lasting liner. The purpose of this study was to analyze the wear rates of patients who underwent THA and received a newer generation HXLPE acetabular insert. Specifically, we compared: 1) linear vector wear amount and 2) linear vector wear rates in patients as an overall cohort and by gender. We also assessed patient satisfaction outcomes comparing preoperative Harris Hip Scores (HHS) to seven-week, one-year, and three-year HHS scores. MATERIALS AND METHODS: A total of 23 patients who underwent total hip arthroplasty (THA) with direct superior approach by a fellowship-trained orthopaedic surgeon at a private practice institution were analyzed after receiving institutional review board approval. Patients had a minimum two-year follow up, with the mean follow up being four years (range, three to five years). All patients received a 36-mm ceramic femoral head with an HXLPE liner. 2D radiographic polyethylene wear analysis was performed using the Martell Hip Analysis Suite (HAS; University of Chicago, Illinois), which has been previously validated in the literature. Outcomes were assessed using Harris Hip Scores. RESULTS: A five-year linear wear rate of 0.073 mm/year (range, 0 to 0.160 mm/year) and an overall mean linear wear rate of 0.096 mm/year (range, 0 to 0.277 mm/year) were found. No significant differences in wear were seen between genders. Additionally, patients reported significantly better results at seven-weeks (83 points [range, 59 to 100 points]) and one-year (94 points [range, 85 to 100 points]) than preoperative (52 points [range, 34 to 73 points]) HSS scores (p<0.05). No patients underwent revision THA. CONCLUSION: The results from this study highlight the benefits of using an HXLPE polyethylene liner in THA patients and further validates previously reported wear rates of HXLPE liners. After an early "wear in" period during the first year, the wear rates steadily decreased over time. This liner showed excellent early outcomes as no patients underwent revision THA. Furthermore, even as early as seven postoperative weeks, patients reported significantly better HHS scores. Future studies should track the same patient cohort over time to help develop a wear-rate prediction model.

Outcomes of Revision Joint Arthroplasty Due to Metal Allergy and Hypersensitivity: A Systematic Review.

BACKGROUND: Lower extremity total joint arthroplasty (TJA) is one of the most successful orthopaedic procedures. However, it is estimated that as many as 10% to 20% of TJAs could fail due to various well-known causes. Furthermore, metal allergy-related complications have recently gained attention as one of the potential causes of failure when the common reasons have been excluded. Reported symptoms from metal allergy can include chronic eczema, joint effusions, joint pain, and limited range of motion. Few studies have explored the outcomes of patients undergoing revisions due to allergic complications. The aim of our study is to quantitatively evaluate the outcomes of revision joint arthroplasty due to metal allergy and hypersensitivity.

The Role of Virtual Rehabilitation in Total Knee and Hip Arthroplasty.

Virtual rehabilitation therapies have been developed to focus on improving care for those suffering from various musculoskeletal disorders. There has been evidence suggesting that real-time virtual rehabilitation may be equivalent to conventional methods for adherence, improvement of function, and relief of pain seen in these conditions. This study specifically evaluated the use of a virtual physical therapy/rehabilitation platform for use during the postoperative period after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The use of this technology has the potential benefits that allow for patient adherence, cost reductions, and coordination of care.

Perioperative Outcomes and Short-Term Complications Following Total Knee Arthroplasty in Chronically, Immunosuppressed Patients.

BACKGROUND: Although there are studies regarding immunosuppressed patients undergoing total knee arthroplasty (TKA) for inflammatory arthritis or osteonecrosis, there is a paucity of studies evaluating immunosuppressed patients undergoing TKA for diagnoses other than these. MATERIALS AND METHODS: We identified all patients undergoing primary TKA for osteoarthritis from 2008-2014 in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. Overall, 111,624 patients were included. The immunosuppressed group consisted of 3,466 patients, and the control group included 108,158. Outcomes measured included operative time, lengths-of-stay, discharge destination, and 30-day complication rates. Univariate analysis was used to compare the outcomes. Multivariate regression analysis was then applied to determine if immunosuppression was an independent risk factor for differences in outcomes. RESULTS: Immunosuppressant use did not change operative time, lengths-of-stay, or discharge disposition. Immunosuppressed patients were at higher risks of developing the following surgical and medical complications: organ/space surgical site infection (SSI), wound dehiscence, deep venous thrombosis (DVT), pneumonia, urinary tract infection (UTI), and systemic sepsis. Return to the operating room and 30-day readmission were also significantly higher in the immunosuppressed group. CONCLUSIONS: Patients taking chronic immunosuppressants and undergoing TKA for osteoarthritis are at higher risk of specific surgical and medical complications. These complications include organ/space SSI, wound dehiscence, DVT, pneumonia, UTI, and systemic sepsis. In addition, these patients were at increased odds of returning to the operating room and being readmitted.

Obesity Epidemic: Is Its Impact on Total Joint Arthroplasty Underestimated? An Analysis of National Trends.

BACKGROUND: Obesity is a well-established risk factor for total joint arthroplasty (TJA) and a number of complications including prosthetic joint infection. The annual changes in the prevalence of obesity among primary, revision, and infected TJA has not been studied at a national level. Given the higher costs of complications of TJA, it is important to understand the association of obesity with the annual trends of revision and infected TJA. QUESTIONS/PURPOSES: (1) Is the prevalence of obesity increasing among patients undergoing THA/TKA? (2) Is the prevalence of obesity increasing among patients undergoing revision THA/TKA? (3) Is the prevalence of obesity increasing among patients with infected THA/TKA? METHODS: Annual volumes of primary, revision, and infected THA and TKA from 1998 to 2011 were obtained from the Nationwide Inpatient Sample. Using mathematical equations, the prevalence of obesity was estimated from relative risks and national obesity prevalence. National obesity prevalence was obtained from public health sources and the relative risk estimates were obtained from previously published meta-analyses and population-based studies. Annual prevalence of obesity was obtained by dividing the number of obese primary/revision/infected procedures in each year by the total number of corresponding procedures in that year. Annual changes in the prevalence of obesity were analyzed using linear regression. RESULTS: The prevalence of obesity is increasing among patients undergoing THA (1998: 60,264 of 154,337 [39%], 2011: 160,241 of 305,755 [52%], increase of 1.05%/year [confidence interval {CI}, 0.95%-1.15%], p < 0.001) and TKA (1998: 143,681 of 251,309 [57%], 2011: 448,712 of 644,243 [70%], increase of 0.97%/year [CI, 0.87%-1.07%], p < 0.001). There was an increasing prevalence of obesity with THA revisions (1998: 16,322 of 34,139 [48%], 2011: 33,304 of 54,453 [61%], increase of 1.04%/year [CI, 0.94%-1.15%], p < 0.001) and in TKA revisions (1998: 16,837 of 26,539 [63%], 2011: 52,151 of 69,632 [75%], increase of 0.89%/year [CI, 0.79%-0.99%], p < 0.001). There was an increasing prevalence of obesity with THA infections (1998: 2068 of 3018 [69%], 2011: 6856 of 8687 [79%], increase of 0.80%/year [CI, 0.71%-0.89%], p < 0.001) and in TKA infections (1998: 3563 of 4684 [76%], 2011: 14,178 of 16,774 [85%], increase of 0.65%/year [CI, 0.57%-0.73%], p < 0.001). CONCLUSIONS: The prevalence of obesity has increased in patients undergoing primary, revision, and infected TJA in United States. The obesity epidemic appears to be related to the growing trends of revision and infection after TJA. With the obesity rates expected to grow further, the revision and infection burden associated with obesity may increase in the future. LEVEL OF EVIDENCE: Level II, prognostic study.

What is the Diagnostic Accuracy of Aspirations Performed on Hips With Antibiotic Cement Spacers?

BACKGROUND: Periprosthetic joint infection is a serious complication after THA and commonly is treated with a two-stage revision. Antibiotic-eluting cement spacers are placed for local delivery of antibiotics. Aspirations may be performed before the second-stage reimplantation for identification of persistent infection. However, limited data exist regarding the diagnostic parameters of synovial fluid aspiration with or without saline lavage from a hip with an antibiotic-loaded cement spacer. QUESTIONS/PURPOSES: We asked: (1) For hips with antibiotic cement spacers, does saline lavage influence the diagnostic validity of aspirations? (2) What is the diagnostic accuracy of preoperative aspirations performed on hips with antibiotic cement spacers using the Musculoskeletal Infection Society (MSIS) criteria, stratified by saline and nonlavage? (3) For hips with antibiotic spacers, what are the optimal thresholds for synovial fluid white blood cell (WBC) count and polymorphonuclear neutrophil (PMN) percentage for diagnosing infections? METHODS: One hundred seventy-four hips (155 patients) with antibiotic-eluting cement spacers inserted between October 2012 and July 2015 were reviewed. Of these, 98 hips (80 patients) met the inclusion criteria and were included in the analysis (77 nonlavage, 21 saline lavage aspirations). Laboratory data from the aspiration and preoperative workup and intraoperative details were collected. Infection status of each hip procedure was determined based on a modified MSIS criteria using serologic, histologic, and intraoperative findings (sinus tract communicating with the joint at surgery or two positive intraoperative periprosthetic cultures with the same organism or two of the three following criteria: elevated erythrocyte sedimentation rate [ESR] [> 30 mm/hour] and C-reactive protein [CRP] [> 10 mg/L], a single positive intraoperative periprosthetic tissue culture, or a positive histologic analysis of periprosthetic tissue [> 5 neutrophils per high power field]). The diagnostic parameters were calculated for the MSIS criteria thresholds for synovial fluid (ie, WBC count > 3000 cells/µL and PMN percentage > 80%). Optimal thresholds were calculated for the corrected synovial WBC count and PMN percentage with a receiver operating characteristic curve. Separate analyses were performed for the hips with successful aspirations (nonlavage group) and those with saline lavage aspirations. RESULTS: The WBC count and PMN percentage were higher in hips with infection than in hips without infection when nonlavage aspirations were done (WBC count, 6680 cells/µL ± 6980 cells/µL vs 2001 ± 4825; mean difference, 4679; 95% CI, 923-8436; p = 0.015; PMN percentage, 83% ± 13% vs 44% ± 30%; mean difference, 39%; 95% CI, 39%-49%; p < 0.001) and the findings between infected and noninfected aspirations were not different when saline lavage aspirations were done (WBC count, 782 cells/µL ± 696 vs 307 cells/µL ± 343; mean difference, 475; 95% CI, -253 to 1203; p = 0.161; PMN percentage, 67% ± 15% vs 58% ± 28%; mean difference, 10%; 95% CI, -11% to 30%; p = 0.331). Aspirations performed without lavage yielded good diagnostic accuracy in all parameters (WBC count, 78% [95% CI, 70%-86%]; PMN percentage. 79% [95% CI, 70%-88%]; positive culture: 84% [95% CI, 81%-90%]; at least one of the above: 79% [95% CI, 70%-88%]); but in the saline lavage group, none had WBC counts above the threshold (diagnostic accuracies for WBC count, 0%; PMN percentage, 71% [95% CI, 62%-86%]; positive culture, 76% [95% CI, 76%-86%]; at least one: 71% [95% CI, 57%-91%]). Because saline lavage did not result in differences between aspirations from infected and noninfected hips, we calculated the optimal thresholds in the nonlavage group only; the optimal threshold for synovial WBC count was 1166 cells/µL and for synovial PMN the percentage was 68%, which corresponds to WBC count diagnostic accuracy of 78% (95% CI, 69%-87%) and PMN percentage accuracy of 78% (95% CI, 69%-87%). CONCLUSIONS: Because the MSIS criteria thresholds resulted in suboptimal sensitivities owing to a higher number of false negatives, we recommend considering lower WBC count and PMN percentage thresholds for hip-spacer aspirations. Furthermore, the WBC count and PMN percentage results from aspirations performed with saline lavage are not reliable for treatment decisions. LEVEL OF EVIDENCE: Level III, diagnostic study.

Cryotherapy Treatment After Unicompartmental and Total Knee Arthroplasty: A Review.

BACKGROUND: Cryotherapy is widely utilized to enhance recovery after knee surgeries. However, the outcome parameters often vary between studies. Therefore, the purpose of this review is to compare (1) no cryotherapy vs cryotherapy; (2) cold pack cryotherapy vs continuous flow device cryotherapy; (3) various protocols of application of these cryotherapy methods; and (4) cost-benefit analysis in patients who had unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA). METHODS: A search for "knee" and "cryotherapy" using PubMed, EBSCO Host, and SCOPUS was performed, yielding 187 initial reports. After selecting for RCTs relevant to our study, 16 studies were included. RESULTS: Of the 8 studies that compared the immediate postoperative outcomes between patients who did and did not receive cryotherapy, 5 studies favored cryotherapy (2 cold packs and 3 continuous cold flow devices). Of the 6 studies comparing the use of cold packs and continuous cold flow devices in patients who underwent UKA or TKA, 3 favor the use of continuous flow devices. There was no difference in pain, postoperative opioid consumption, or drain output between 2 different temperature settings of continuous cold flow device. CONCLUSION: The optimal device to use may be one that offers continuous circulating cold flow, as there were more studies demonstrating better outcomes. In addition, the pain relieving effects of cryotherapy may help minimize pain medication use, such as with opioids, which are associated with numerous potential side effects as well as dependence and addiction. Meta-analysis on the most recent RCTs should be performed next.

Administrative Databases Can Yield False Conclusions-An Example of Obesity in Total Joint Arthroplasty.

BACKGROUND: Research using large administrative databases has substantially increased in recent years. Accuracy with which comorbidities are represented in these databases has been questioned. The purpose of this study was to evaluate the extent of errors in obesity coding and its impact on arthroplasty research. METHODS: Eighteen thousand thirty primary total knee arthroplasties (TKAs) and 10,475 total hip arthroplasties (THAs) performed at a single healthcare system from 2004-2014 were included. Patients were classified as obese or nonobese using 2 methods: (1) body mass index (BMI) ≥30 kg/m2 and (2) international classification of disease, 9th edition codes. Length of stay, operative time, and 90-day complications were collected. Effect of obesity on various outcomes was analyzed separately for both BMI- and coding-based obesity. RESULTS: From 2004 to 2014, the prevalence of BMI-based obesity increased from 54% to 63% and 40% to 45% in TKA and THA, respectively. The prevalence of coding-based obesity increased from 15% to 28% and 8% to 17% in TKA and THA, respectively. Coding overestimated the growth of obesity in TKA and THA by 5.6 and 8.4 times, respectively. When obesity was defined by coding, obesity was falsely shown to be a significant risk factor for deep vein thrombosis (TKA), pulmonary embolism (THA), and longer hospital stay (TKA and THA). CONCLUSION: The growth in obesity observed in administrative databases may be an artifact because of improvements in coding over the years. Obesity defined by coding can overestimate the actual effect of obesity on complications after arthroplasty. Therefore, studies using large databases should be interpreted with caution, especially when variables prone to coding errors are involved.