Technology Review: CT Scan-Guided, 3-Dimensional, Robotic-Arm Assisted Lower Extremity Arthroplasty.

Robotic-arm assisted lower extremity arthroplasty using computed tomography scan (CT)-based 3-dimensional (3D) modeling operative technologies has increasingly become mainstream over the past decade with over 550,000 procedures performed between first use in 2006 and November 2021. Studies have demonstrated multiple advantages with these technologies, such as decreased postoperative pain and subsequent decreased narcotic usage, decreased lengths of stay, less complications, reduced damage to soft tissues, decreased readmissions, as well as economic advantages in the form of meaningful cost savings for payors. The purpose of this report was to clearly and concisely summarize the good-to-high methodology peer-reviewed, published literature regarding CT scan-based, 3-dimensional robotically-assisted unicompartmental knee arthroplasty, total knee arthroplasty, and total hip arthroplasty stratified by: (1) prospective randomized studies; (2) database comparison studies; (3) national registry studies; (4) health utility studies; (5) comparison studies; and (6) basic science studies. A literature search was conducted and, after applying inclusion criteria, each study was graded based on the modified Coleman methodology score ("excellent" 85-100, "good" 70-84, "fair" 55-69, "poor" <54 points). A total of 63 of 63 good-to-excellent methodology score reports were positive for this technology, including 11 that demonstrated decreased pain and/or opioid use when compared to traditional arthroplasty techniques. The summary results of these high-quality, peer-reviewed published studies demonstrated multiple advantages of this CT scan-based robotic-arm assisted platform for lower extremity arthroplasty.

Long-term Wear Data From a Prospective Multicenter Study of Second-Generation Highly Cross-linked Polyethylene Inserts in Total Hip Arthroplasty.

In a prospective multicenter trial on highly cross-linked polyethylene inserts in patients undergoing total hip arthroplasty, 118 patients consented to 10-year follow-up. Medium-term follow-up results showed low wear at 5 and 7 years after surgery. The current study focuses on long-term data at 10 years. Patients were followed up by either phone or office visit to collect long-term clinical data including Harris hip score and adverse events. There were 2 deaths and 2 revisions, 1 at 6.5 years for pelvic cyst and severe pain and another at 8.0 years for recurrent dislocation. For wear analysis, suitable radiographic images for 48 patients (52 hips) at minimum 10-year follow-up were available. Mean age of the cohort was 62.5 years (62% female). Femoral head penetration was measured using Martell's method from the radiographic images between the 6-week and the subsequent follow-ups. Polyethylene wear rate was calculated from the penetration data. Descriptive statistics were performed. There was no evidence of significant oxidation or locking mechanism failure. Mean Harris hip score of the group was 94.3. No osteolysis was noted by an independent radiographic reviewer. The slope of the bestfit regression line to the femoral head penetration data, which represents the overall linear wear rate of the polyethylene, was 0.014 mm/y. The wear rate was significantly below the 0.100 mm/y critical threshold for development of osteolysis. Volumetric wear rate was calculated to be 11.6 mm3/y. The second-generation highly cross-linked polyethylene acetabular inserts had low wear in the long term (10.3 years) with no incidence of osteolysis. [Orthopedics. 2018; 41(4):e529-e533.].

Wound Closure Techniques for Total Knee Arthroplasty: An Evidence-Based Review of the Literature.

BACKGROUND: This literature review is aimed at identifying the different methods for superficial and deep wound closure in total knee arthroplasty and evaluating their outcomes. We evaluated (1) closure time, (2) infection and other complication rates, and (3) local wound-related outcomes. METHODS: A thorough search of the literature was performed using 3 electronic databases. Inclusion criteria included manuscripts that were written in English and available in full-text format. Reports were stratified into those that describe deep closure (7) and those that describe superficial closure (11). RESULTS: In superficial closure, staples may provide the fastest closure, adhesives, lower incidence of superficial complications, and subcuticular suture closures, greatest blood flow. In deep closure, barbed sutures may allow for faster closure time while providing similar postoperative complication rates and outcomes when compared to traditional sutures. The use of barbed sutures has been shown to utilize fewer resources and may potentially lead to a slight reduction in costs. CONCLUSION: Ultimately, no optimal closure technique has been developed, and current studies do not provide a clear evidence-based answer. This field needs much more evidence-based studies before one can draw conclusions. Even though some of these studies are prospective and randomized, they may not be generalizable. Also, many of the studies have small numbers and are subject to type II errors and fragility. Certainly, more studies are needed to truly understand the advantages and disadvantages of these new methods. Nevertheless, this review allows orthopedists to evaluate the differences between closure methods.

Hip and Knee Arthroplasty Orthopedic Literature in Medical Journals-Is It Negatively Biased?

BACKGROUND: Healthcare policy is often determined by well-designed studies most often published in high-impact medical journals. However, concern about the presence of publication bias against lower-extremity arthroplasty-related studies has called into question some of the validity of certain reports. There are only a few studies investigating the presence of the bias in high-impact medical journals against lower-extremity arthroplasty intervention, particularly in the Journal of American Medical Association (JAMA), New England Journal of Medicine (NEJM), and the Lancet. Thus, the purpose of this study was to assess (1) the distribution of positive, neutral, and negative results; (2) the number of reports focused on lower-extremity arthroplasty complications among these 3 journals; and (3) difference in bias between 2 time periods (1975 to 1990 and 2000 to 2016). METHODS: A review of the literature from 3 major medical journals (NEJM, Lancet, and JAMA) was performed using PubMed electronic databases, which retrieved articles between January 1976 and December 2016. Studies were categorized as being positive, neutral, and negatively biased by 2 reviewers. Studies were categorized as reporting on lower-extremity arthroplasty-related complications if they were based on complications including deep vein thrombosis, infection, metal-related complication, fat embolism, readmission, or mortality. In addition, we have compared the journal bias between 2 different time points (1975 to 1990 and 2000 to 2016). Descriptive analyses were performed to assess frequencies. Chi-squared analysis was conducted for categorical variables, whereas a z-test was performed for dichotomous data. RESULTS: When assessing all 3 journals, there were 46 positive (30.3%), 46 negative (30.3%), and 60 neutral reports (39.5%). There was no statistically significant difference in classification proportions between the 3 groups (P = .905). There was a higher percentage of medical literature reporting on the complications of arthroplasty (55.9%); however, this was not statistically significant (z-score = 1.38; 95% confidence interval, 0.48-0.64; P = .17). There was no difference in overall journal reporting between 1975 to 1990 and 2000 to 2016 (P = .548). CONCLUSION: There was no evidence of publication bias of lower-extremity arthroplasty reports in the major medical journals (JAMA, NEJM, and Lancet). However, there were more published studies reporting on complications of lower-extremity arthroplasty. This may be due to systematic bias among journal editors in these journals, or due to low journal submission reporting noncomplications after arthroplasty intervention. We did not find the time period to be a factor in bias reporting of orthopedic literature in major medical journals. More work is needed to verify the results of this study.

Quadriceps and Hamstring Muscle Strength Improves After Unicompartmental Knee Arthroplasty.

INTRODUCTION: The ability to reach functional capacity following knee arthroplasty depends on the strength of the quadriceps and hamstring muscles. Following total knee arthroplasty, weakness of these muscles can persist for up to one year postoperatively; however, this phenomenon is not well-studied in unicompartmental knee arthroplasty (UKA) patients. Therefore, we assessed: 1) quadriceps muscle strength; 2) hamstring muscle strength; and 3) correlation to functional outcomes. MATERIALS AND METHODS: A review of all patients with medial compartment osteoarthritis treated with UKA at a minimum of one-year follow-up was performed. This yielded 26 patients (32 knees), comprising of eight females and 18 males who had a mean age of 67 years (range, 47 to 83 years). Muscle strength was assessed pre-and postoperatively via dynamometer. Functional outcomes were assessed using Knee Society Scores (KSS). Comparisons of groups were performed by paired t-tests. RESULTS: At a minimum one-year postoperatively, quadriceps muscle strength was 27 Nm (range, 13 to 71Nm) and hamstring muscle strength was 19.5Nm (range, 7 to 81Nm). Quadriceps muscle strength increased by 40% (p=0.002) and hamstring muscle strength by 26% (p=0.057). The mean KSS pain was 97 points (range, 85 to 100 points) and mean KSS function was 90 points (range, 45 to 100 points) at the final follow-up. Range of motion was 125° (range, 110° to 135° ) at the final follow-up. The Pearson Correlation Coefficient for postoperative extension strength and postoperative flexion strength to postoperative KSS functional scores were 0.268 and 0.220 respectively. CONCLUSION: Within one-year following UKA, patients can expect restoration of quadriceps and hamstring muscle strength with a corresponding functional improvement. Although long-term follow-up is warranted to determine sustainability, the short-term results demonstrate excellent restoration of function.

Does Length of Stay Influence How Patients Rate Their Hospitalization After Total Hip Arthroplasty?

BACKGROUND: The reimbursement for medical services by Medicare and Medicaid (CMS) has recently changed from fee-for-service to quality-based payments. This is being implemented through the use of patient administered surveys, most commonly Press Ganey. With a recent strive for fast-track total hip arthroplasty (THA), it is important to ascertain whether length-of-stay (LOS) in post-THA patients influences the Press Ganey scores and overall hospital ratings. Therefore, we looked at: 1) Which Press Ganey survey factors affect overall hospital rating in patients who have a short (=2) or longer (>2) length of stay; and 2) whether hospital satisfaction is different between patients who have varied lengths of stay. MATERIALS AND METHODS: A query of the Press Ganey database at our institution was performed between November 2009 and January 2015. We identified 692 patients who had a mean age of 62 years (range, 15 to 91 years). These patients were stratified into two cohorts based on LOS (=two days, n=403; >two days, n=289). Multiple regression analyses were performed using weighted means of each Press Ganey question category to identify their influence ( b) on hospital ratings. We assessed differences in demographics and survey responses between the two cohorts using x2 tests for categorical data and t-tests for continuous data. RESULTS: There was no statistically significant difference found between our two cohorts in hospital rating after adjusting for gender and ASA score. In patients who had short lengths-of-stay (LOS= two days), the overall hospital rating was most influenced by communication with nurses ( b=0.335, p= 0.004), followed by responsiveness of hospital staff ( b=0.313, p=0.006), and communication with doctors ( b=0.208, p=0.049) after adjusting for gender and ASA score. For patients who stayed longer (LOS>two days), the most important factor in hospital ratings was communication with nurses ( b=0.332, p= 0.007), followed by hospital environment ( b=0.312, p=0.002), communication with doctors ( b=0.233, p=0.013), and staff responsiveness (b=0.223 p=0.042). CONCLUSION: Short (LOS=2) and long (>two days) lengths of stay did not affect overall hospital rating. However, amongst both cohorts, communication with nurses, staff responsiveness, and communication with doctors were positively correlated with hospital ratings. Hospital environment also played a significant role in overall hospital ratings for patients who had an LOS >two days. More studies should be conducted to assess if the use of minimally invasive THA affects overall hospital ratings.

Dual Mobility Acetabular Cups in Primary Total Hip Arthroplasty in Patients at High Risk for Dislocation.

INTRODUCTION: Postoperative dislocation occurs in approximately 2% of primary total hip arthroplasties (THAs). Risk factors associated with dislocation include: age of 70 years or older, body mass index (BMI) of 30 kg/m2 or greater, alcohol abuse, and neuro-degenerative diseases such as multiple sclerosis or Parkinson's disease. As a result, dual-mobility articulations, which have been typically used for revision procedures, have become an increasingly popular option for these "at risk" primary THAs. Few studies have assessed their use in this complex patient population. Therefore, the purpose of this study was to assess: 1) survivorship; 2) radiographic outcomes (cup migration, progressive radiolucencies, and changes in component position); 3) Harris Hip Scores; and 4) complications of the dual-mobility articulation in the setting of primary THA for patients at high risk for dislocation. MATERIALS AND METHODS: Five participating surgeons performed 495 primary cementless THAs between January 2011 and December 2013. During this time, four of the five surgeons used dual-mobility articulations whenever the acetabular cup size was 52 mm or greater to allow for a 28 mm head, while one surgeon used it when the cup size was less than 52 mm to allow for an effective head size of 38 mm. The remaining surgeon used it for all THAs. Of the 495 patients, 453 (92%) received dual-mobility articulations, of which, 43 patients (10%) were lost to follow-up before the two year minimum. The remaining 410 patients were further assessed to determine those who were considered high risk for dislocation (age = 70 years, BMI =30 kg/m2, had a diagnosis of alcohol abuse, or had a neuro-degenerative disorder). Two hundred forty-nine patients were included in the analysis (103 men, 146 women) who had a mean age of 66 years (range, 24 to 90 years). The mean follow-up was 3.3 years (range, 2 to 5 years). Kaplan-Meier analysis was performed to assess aseptic and all-cause acetabular cup survivorship. Radiographs were evaluated for cup migration, progressive radiolucencies, and any changes in component position. Clinical outcomes were assessed using the Harris Hip Score (HHS), and any surgery-related complications were recorded. RESULTS: The survivorship to aseptic failure (n= 1) and all-cause (aseptic, n= 1; septic, n= 1) Kaplan-Meier acetabular component survivorships were 99.6% (95% confidence interval [CI], 99.1% to 99.9%) and 99.2% (95% CI, 98.5% to 99.9%), respectively. One hip had impingement of an anteverted cup, resulting in trunnion notching, and required revision of the cup and stem. Another hip had a deep infection, which was treated with a two-stage revision procedure. There were no dislocations in this cohort. No progressive radiolucencies or component positional changes were seen on radiographic assessment. Patients reported a mean HHS of 92.5 (range, 47 to 100 points) at final follow-up. Surgical complications included one polyethylene liner that was incompletely seated, and one loose femoral stem, which required revision of only the femoral component. CONCLUSIONS: At short-term follow-up, dual-mobility articulations in primary THA offer survivorship, outcomes, and complications comparable to conventional THA designs in patients who are at increased risk for postoperative dislocation. Serious complications, such as polyethylene wear and intraprosthetic dislocations, have occasionally been reported with the use of these components. Therefore, future studies should be prospective, multi-center, and have longer-term follow-up to determine the true benefit of modular dual-mobility articulations in patients who are at high risk for dislocation.

Do Press Ganey Scores Correlate With Total Knee Arthroplasty-Specific Outcome Questionnaires in Postsurgical Patients?

BACKGROUND: The purpose of this study was to assess whether Center for Medicaid and Medicare services-implemented satisfaction (Press Ganey [PG]) survey results correlate with established total knee arthroplasty (TKA) assessment tools. METHODS: Data from 736 patients who underwent TKA and received a PG survey between November 2009 and January 2015 were analyzed. The PG survey overall hospital rating scores were correlated with standardized validated outcome assessment tools for TKA (Short form-12 and 36 Health Survey; Knee Society Score; Western Ontario and McMaster Universities Arthritis Index; University of California, Los Angeles; and visual analog scale) at a mean follow-up of 1154 days post-TKA. RESULTS: There was no correlation between PG survey overall hospital rating score and the above-mentioned outcome assessment tools. CONCLUSION: Our study shows that there is no statistically significant relationship between established arthroplasty assessment tools and the PG overall hospital rating. Therefore, PG surveys may not be an appropriate tool to determine reimbursement for orthopedists performing TKAs.

Economic evaluation of different suture closure methods: barbed versus traditional interrupted sutures.

Healthcare systems are receiving increasing pressures from payers, such as the Centers for Medicare and Medicaid (CMS), to reduce the costs associated with procedures, and with the implementation of the Affordable Care Act, high costs are addressed through pay-for-performance programs. Thus, multiple areas of total knee arthroplasty (TKA) surgery are under scrutiny, including surgical times, material costs, and the costs of associated complications and readmissions. Suture type has been determined to be a factor that may influence closure times, as well as direct material costs. Therefore, the purpose of this review was to compare: (I) the cost of using barbed vs. conventional interrupted sutures; (II) the additional cost of differences in complications, if any; (III) to extrapolate cost savings on a hospital and national level; and (IV) to discuss the role of these findings on hospital savings and the effect on bundled payments. It was found that the main factors affecting differences in overall costs between barbed and standard interrupted suture were material cost and closure time. Many studies have demonstrated greater cost savings with the barbed suture due to shorter operative times, despite the higher material costs. The majority of studies also demonstrated similar complication rates between the suture types, and thus these are unlikely to affect the cost difference. However, to the best of our knowledge, there are no TKA studies in the literature evaluating the effect of suture type and associated complications on lengths of stay and readmission rates. Thus, it is unclear how these cost savings will translate to reimbursements rates and the role that they might play in bundled payments. Several studies in other specialties demonstrate decreased infection rates with the use of barbed sutures, which, if found to be true for TKA can be extrapolated to 3 million dollars of savings in revision TKA costs. Further studies on this topic are needed to define these relationships.

Improvement in hamstring and quadriceps muscle strength following cruciate-retaining single radius total knee arthroplasty.

BACKGROUND: The ability to reach full functional capacity following total knee arthroplasty (TKA) is reliant on the strength of the quadriceps and hamstring muscles. Weakness of these muscles can persist anywhere from 1 to 3 years post-operatively. There remains considerable controversy as to what factors influence restoration of muscle strength after TKA. Implant designs have been implicated in the ability of patients to recover. Currently there is a paucity of literature available describing the influence of patient characteristics, surgical factors, and clinical outcomes on quadriceps and hamstring muscle strength following TKA with a cruciate-retaining, single radius (SR) implant. For this reason, we sought to investigate TKA patients for: (I) quadriceps muscle strength; (II) hamstring muscle strength; (III) flexion/extension (F/E) ratio; (IV) clinical outcome scores; (V) influence of patient characteristics on muscle strength at one-year post-operatively. METHODS: A review of TKA patients who were assessed for hamstring and quadriceps muscle strength was conducted. A total of 39 patients (26 men and 13 women), who had a mean age of 68 years (range, 51 to 88 years) were included. Isokinetic dynamometer testing at 180 degree/second for 3 sets of 10 repetitions in extension and flexion were performed by an independent physical therapist to assess dynamic concentric torque of the hamstrings and quadriceps muscle. F/E ratios were calculated. TKA was performed via subvastus (n=20) or midvastus (n=19) approach. Subgroup analysis for surgical approach, concomitant spinal pathology (n=11), gender, age and body mass index (BMI) were performed. Knee Society Scores (KSS) and range of motion (ROM) were assessed at each visit. Comparisons of groups were performed using paired t-tests. RESULTS: Mean postoperative relative extension torque was 23 Nm/kg (range, 9 to 43 Nm/kg), representing a mean increase of 38% (range, -16% to 100%; P=0.0267) from pre-operative status. A mean increase of 27% (range, -15% to 100%; P=0.0433) in flexion strength and mean relative flexion torque of 19 Nm/kg (range, 8-37 Nm/kg) was observed. Pre-operative mean F/E ratio was 0.8 and 0.9 post-operatively (P=0.3028). Men demonstrated significantly greater improvements in flexion compared to women (22% vs. 12%; P<0.0001), but gender had no influence on improvement in extension (27% vs. 15%; P=0.0537). Postoperative F/E was similar for males (0.8) and females (0.9; P=0.4454). Surgical approach did not influence quadriceps muscle strength (P=0.1786) or hamstrings muscle strength (P=0.9592). History of spine pathology had no impact on muscles strength (hamstring, P=0.5684; quadriceps, P=0.7221). For the overall group, a mean KSS pain score was 96 points (range, 84 to 100 points), KSS function was 96 points (range, 80 to 100 points), and mean ROM of 0 to 114 degrees. CONCLUSIONS: Restoration of quadriceps and hamstring muscle strength can be expected at 1 year post-operatively regardless of gender, surgical approach or concomitant spinal pathology. Further comparative investigation on the impact of implant design on hamstring and quadriceps muscle strength is warranted. However, the use of a SR, CR TKA system demonstrated significant improvements post-operatively in quadriceps and hamstring strength.

Total knee arthroplasty fibrosis following arthroscopic intervention.

BACKGROUND: Although arthroscopy is generally considered to be a relatively benign procedure with limited trauma to periarticular soft tissues, post-arthroscopic bleeding as well as osmolality differences between the normal saline used to irrigate and the native synovial fluid (282 vs. 420 mOs) can lead to capsular reactions. Therefore, the purpose of this study was to evaluate whether capsular reaction occurred after knee arthroscopy, by comparing a matched cohort of patients who either did or did not undergo prior arthroscopic surgery. Specifically, we compared histological features such as: (I) synovial thickness; (II) cellularity; and (III) the amount of fibrous tissue for each cohort. METHODS: Prior to their total knee arthroplasty (TKA), 40 consecutive patients who had previously undergone arthroscopy were matched to 40 consecutive patients who had not. During each patient's TKA, a biopsy of the capsule and fat pad was taken and formalin sections were sent to pathology to assess for synovial thickness, cellularity, and the amount of fibrous tissue. The pathologist was blinded to the groupings. Findings for all histologic features were classified as equivocal, slight to moderate, and moderate to severe. RESULTS: There were a significantly higher proportion of patients who had increased synovial thickness in the prior arthroscopy group as compared to the no-prior arthroscopy group (97.5% vs. 0%, P<0.001). Additionally, there were a significantly higher proportion of patients who had increased cellularity in the prior arthroscopy group as compared to the no-prior arthroscopy group (60.0% vs. 0%, P<0.001). There were also a significantly higher proportion of patients who had increased fibrous tissue in the prior arthroscopy group as compared to the no-prior arthroscopy group (95% vs. 62.5%, P<0.001). CONCLUSIONS: Arthroscopic surgery may have long-term effects on capsular tissue as surgical observations of patients with prior arthroscopic surgery from this study found that the capsule is thicker and denser. Histologic assessment confirms there may be increased synovial thickness, increased cellularity, as well as thickening of fibrous tissue. This preliminary study and further evaluation are required. This suggests that arthroscopic surgery may have long-lasting effects on periarticular tissue especially the capsular tissue which may have implications for pain and functional recovery.

Novel venous thromboembolic disease (VTED) prophylaxis for total knee arthroplasty-aspirin and fish oil.

BACKGROUND: Despite the demonstrated success of multiple anticoagulation therapies for post-operative prophylaxis of thromboembolic disease in lower extremity arthroplasties, each modality comes with a unique set of limitations. Thus, the ideal anticoagulation medication which provides adequate therapy with minimal cost, complications, or added patient work is yet to be defined. One promising novel thrombophylactic supplement is fish oil, as many preliminary clinical trials have demonstrated a protective effect of fish oil against thrombosis in multiple clinical settings. In addition, others have demonstrated synergistic effect when combined with aspirin. However, there are paucity of studies that compared combined aspirin and fish oil therapy for venous thromboembolism prophylaxis with other pharmacological agents, especially in the field of orthopaedics. Therefore, this study evaluated: (I) risk of post-operative deep vein thrombosis (DVT) and pulmonary embolism (PE), and (II) bleeding complications; among patients who had primary total knee arthroplasty (TKA) and received one of the following regimens: (i) 325 mg aspirin and mechanical pulsatile stocking; (ii) rivaroxaban; or (iii) 325 mg aspirin and 1,000 mg fish oil. METHODS: This was a 6-year prospective study analyzing the postoperative thromboembolic prophylaxis received by patients who underwent primary TKA. Patients who had a previous history of thromboembolic disease were excluded from the study due to an increased risk of recurrent clot formation. A total of 850 patients were enrolled. A total of 300 patients enrolled between October 2011 and June 2013 received 325 mg aspirin and mechanical pulsatile stocking, while 250 patients enrolled between June 2013 and December 2014 received rivaroxaban. A total of 300 patients enrolled between January 2015 and July 2017 received 325 mg aspirin and 1,000 mg fish oil. Major venous thromboembolic events (VTEs) and bleeding complications within the first 90 days post-operatively were recorded in each cohort. The odds ratios (ORs) and 95% confidence intervals (CIs), for thromboembolic and bleeding events were calculated and compared between the aspirin and fish oil cohort vs. aspirin and pulsatile stocking cohort, and aspirin and fish oil cohort vs. rivaroxaban cohort. A P value of <0.05 was used to determine statistical significance. RESULTS: A total of 25 DVT events were recorded including 1 of 300 (0.33%) in the aspirin and fish oil cohort, 22 of 300 (7.33%) in the aspirin and pulsatile stocking cohort and 2 of 250 (0.8%) in the rivaroxaban cohort. When comparing ORs, patients who received aspirin and fish oil demonstrated significantly lower risk for thromboembolic events when compared to the aspirin and pulsatile stocking group (OR: 0.045; 95% CI: 0.0061-0.3394; P<0.05). When compared to the rivaroxaban cohort the ORs did not differ significantly (OR: 0.416; 95% CI: 0.0376-4.6223; P>0.05). In addition, no PE events were recorded in any of the cohorts. When compared to rivaroxaban, the fish oil and aspirin cohort demonstrated significantly lower incidence of bleeding episodes (1 of 300, 0.33% vs. 30 of 250 patients, 12%; OR: 0.0278; 95% CI: 0.0038-0.2051; P<0.05). No bleeding events were recorded in the aspirin and pulsatile stocking cohort. CONCLUSIONS: This study demonstrated the potentially synergistic anti-thromboembolic effect of aspirin and fish oil in the prevention of post-operative venous thromboembolism in primary TKA patients. Based on the results from this study, the authors conclude that the combination of aspirin and fish oil maybe an excellent thromboprophylactic modality for patients to use after TKA. These results warrant further, larger prospective studies analyzing the use of fish oil supplements in VTE prophylaxis.

What Influences How Patients Rate Their Hospital After Total Hip Arthroplasty?

BACKGROUND: Centers for Medicare and Medicaid Services are now using results from patient satisfaction surveys, such as Press Ganey, for reimbursement. It is unknown what factors influence scores on satisfaction surveys in post-total hip arthroplasty (THA) patients. The purpose of this study was to evaluate what influences these scores in THA patients. Specifically, we aimed to evaluate: (1) how pain control affects the patients' perception of their orthopedist, nursing staff, and overall hospital satisfaction; (2) the individual impact of these factors on overall hospital satisfaction after THA; and (3) the impact of lengths of stay, age, body mass index (BMI), and American Society of Anesthesiology (ASA) scores on overall satisfaction. METHODS: To assess whether pain management influences patients' perception of the orthopedist, a correlation analysis was performed between pain control and perception of their doctor. Similar analyses were performed to determine the relationship between pain management and patients' perception of their treating nurse, as well as overall satisfaction. A multiple regression analysis was performed to determine which of the aforementioned factors have the greatest impact on overall satisfaction. To determine the impact of length of stay on overall hospital satisfaction, a correlation analysis was performed between these 2 variables. Similar analyses were performed for age, BMI, and ASA scores. RESULTS: Patients' perception of pain control was significantly positively correlated with the perception of their orthopedist, nurse, and overall hospital satisfaction. Multiple regression analysis demonstrated that patients' perception of nurses and orthopedists yielded a significantly positive influence on overall hospital satisfaction. A significant negative correlation existed between lengths of stay and hospital satisfaction. There were no significant correlations between age, BMI, and ASA scores and overall hospital rating. CONCLUSION: Post-THA patients associate pain management with hospital satisfaction, as well as their perception of their treating nurses and orthopedists. Overall satisfaction was most impacted by patients' perception of their nurse, followed by their orthopedist. In addition, there was an association between shorter length of stay and higher overall satisfaction. These results are of paramount importance because by recognizing factors that affect scores on satisfaction surveys, orthopedic surgeons can direct efforts to improve post-THA satisfaction and optimize reimbursements.

What Influences How Patients Rate Their Hospital After Total Knee Arthroplasty?

INTRODUCTION: There is increasing pressure from Centers for Medicare and Medicaid Services (CMS) to report quality measures for all hospitalizations. These quality measures are determined based on results from satisfaction surveys, such as Press Ganey® (PG) (Press Ganey® Performance Solutions, Wakefield, Massachusetts). Included in this particular survey element are questions regarding staff, including nurses and doctors, as well as items such as pain control. The results of these surveys will dictate the amount doctors are compensated for their services. Therefore, this study was undertaken to evaluate the effect of treating orthopaedists and nurses, as well as pain control, on PG surveys in patients who underwent total knee arthroplasty (TKA). Specifically, we aimed to ascertain the effect of these factors on how post-TKA patients perceive: 1) their orthopaedist, and 2) their overall surgical experience. MATERIALS AND METHODS: We queried the Press Ganey® Database for all patients who underwent a TKA at our institution between November 2009 and January 2015. A weighted mean of question domains was utilized since each had multiple questions. In order to assess if pain management influences orthopaedist perception, a correlation analysis was performed between pain control and perception. In order to assess the influence of pain management on surgical experience, we performed a correlation analysis between pain control and overall hospital rating. A multiple regression analysis was performed using the hospital rating as the dependent variable to determine the most influential factors on surgical experience. RESULTS: Our analysis demonstrated a significantly positive correlation between patient perception of their pain control and their orthopaedist. There was a significant positive correlation between patient's perception of their pain control and their overall surgical experience. Multiple regression analysis using overall surgical experience as the dependent variable demonstrated a significant positive influence of perception of nurses and orthopaedists. Pain management positively influenced surgical experience; however, this was not significant. CONCLUSIONS: We found that perception of pain control in post-TKA patients affects perception of the treating orthopaedists, as well as their overall surgical experience. In addition, perception of orthopaedists and nurses both outweigh perception of pain control on overall surgical experience, with nurses being the most important. Orthopaedists should focus on staff education-particularly nurses-and educate them in order to optimize results on PG surveys and, ultimately, improve patient satisfaction. Further studies should correlate current standardized scoring systems and questionnaires for TKA with PG surveys in order to recognize gaps that need to be bridged to improve post-TKA patient satisfaction.

Low Frequency of Early Complications With Dual-mobility Acetabular Cups in Cementless Primary THA.

BACKGROUND: Dislocation complicates 1% to 5% of primary total hip arthroplasties (THAs). As a result, some surgeons consider dual-mobility articulations, which are usually used in the revision setting to decrease the likelihood of dislocation, as an option for primary THA. However, few studies have evaluated their use in this setting. QUESTIONS/PURPOSES: (1) What is the cup survivorship when the dual-mobility articulation is used in the setting of primary THA? (2) What are the clinical outcomes with this approach? (3) What are the radiographic outcomes? (4) What are the complications of dual-mobility articulations in primary THA? METHODS: Between 2011 and 2013, the five participating surgeons performed 495 cementless primary THAs. During that time, one of the five surgeons used dual-mobility articulations for all THAs, and the other four used it whenever the acetabular cup size was 52 mm or greater to enable a 28-mm head. Of the 495 patients, 453 (92%) were performed using this device. Smaller patients were treated with a standard THA. Of the 453 patients, a total of 43 patients (10%) were lost to followup before the 2-year minimum. The resulting 410 patients who were included in the analysis (164 men, 246 women) had a mean age of 64 years (SD, 12 years). The mean followup was 3 years (SD, 0.7 years). We performed Kaplan-Meier analyses to assess survivorship to aseptic failure and all-cause acetabular component survivorship. Clinical outcomes were evaluated using the Harris hip score (HHS); radiographs were assessed for cup migration, progressive radiolucencies, and positional changes of the components; and any surgery-related complications were recorded. RESULTS: The survivorship to aseptic failure and all-cause acetabular component survivorship was 99.8% (failures, n = 1) (95% confidence interval [CI], 4.517-4.547) and 99.3% (failures, aseptic, n = 1; septic, n = 2) (95% CI, 4.494-4.543); one hip had trunnion notching caused by impingement of a malpositioned cup, which was treated with revision of the cup and stem; and two patients had periprosthetic infections that were treated with two-stage revisions. There were no dislocations. Patients had a mean HHS of 94 (SD, 6) at final followup. On radiographic evaluation, no progressive radiolucencies or positional changes of the components were identified. Surgical complications included one traumatic avulsion of the abductors, one traumatic avulsion of the greater trochanter, which was repaired without revision of any of the components, and one loose femoral stem, which required revision of the femoral component only. CONCLUSIONS: Dual-mobility cups in primary THA yield seemingly comparable survivorship and complications to conventional THA bearings at short-term followup. Because serious complications have occasionally been reported with the use of these bearings, larger, longer term, comparative-and ideally, randomized-trials will be needed to establish the superiority of one approach over the other. Until or unless such studies show the superiority of dual-mobility designs for primary THA, we recommend that in the setting of uncomplicated primary THA, dual-mobility articulations be used only in centers that track their results carefully or in research protocols. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Bariatric Orthopaedics: Total Hip Arthroplasty in Super-Obese Patients (Those with a BMI of ≥50 kg/m2).

BACKGROUND: The purpose of this study was to assess the clinical and patient-reported outcomes of primary total hip arthroplasty in super-obese patients (those with a body mass index [BMI] of ≥50 kg/m(2)) compared with a matched group of patients who had a normal BMI (<30 kg/m(2)). A secondary objective was to assess patients' experiences in finding a treating surgeon. METHODS: Forty-eight hips in forty-five patients who had a minimum BMI of 50 kg/m(2) and who had undergone a primary total hip arthroplasty at one of four high-volume institutions between 2001 and 2010 were reviewed. This included twenty-six women and nineteen men who had a mean age of fifty-four years (range, thirty-six to seventy-one years) and who were followed for a mean time of six years (range, four to twelve years). These patients were compared in a 1:3 ratio with a non-obese matched group (those with a BMI of <30 kg/m(2)) of 135 patients who had undergone total hip arthroplasty during the same time period by the same surgeons. The outcomes evaluated included implant survivorship, complication rates, Harris hip scores, 36-item Short-Form (SF)-36 questionnaires, University of California Los Angeles (UCLA) activity scores, and patient experience in finding a treating surgeon. RESULTS: The super-obese group had a 4.5 times higher odds ratio of undergoing a revision when compared with the matching group (p = 0.06); the overall implant survivorship was 89.6% for the super-obese group and 97.8% for the matching group. The super-obese group also had a significantly higher odds ratio (7.7) of complications compared with the matching group (p = 0.017). The super-obese group also had significantly lower mean values for the Harris hip score (82 points for the super-obese group compared with 91 points for the matched group; p = 0.002), the SF-36 Physical Component Summary score (39 points for the super-obese group and 49 points for the matched group; p = 0.001), the SF-36 Mental Component Summary scores (46 points for the super-obese group and 58 points for the matched group; p = 0.001), and the UCLA activity score (3.9 points for the super-obese group compared with 6.2 points for the matched group; p = 0.001). Compared with the matched group, super-obese patients were evaluated by a larger number of orthopaedic surgeons prior to undergoing total hip arthroplasty. CONCLUSIONS: The clinical and patient-reported outcomes of primary total hip arthroplasty were lower in the super-obese patients. These patients also faced challenges in finding surgeons who would perform their procedure. Super-obese patients may benefit from counseling with their treating surgeon to set realistic expectations with regard to the outcomes of their procedure.