Antibacterial and anti-inflammatory ultrahigh molecular weight polyethylene/tea polyphenol blends for artificial joint applications.

Periprosthetic joint infection (PJI) is one of the main causes for the failure of joint arthroplasty. In view of the limited clinical effect of oral/injectable antibiotics and the drug resistance problem, there is a pressing need to develop antibacterial implants with therapeutic antimicrobial properties. In this work, we prepared a highly antibacterial ultrahigh molecular weight polyethylene (UHMWPE) implant by incorporating tea polyphenols. The presence of tea polyphenols not only improved the oxidation stability of irradiated UHMWPE, but also gave it the desirable antibacterial property. The potent antibacterial activity was attributed to the tea polyphenols that produced excess intracellular reactive oxygen species and destroyed the bacterial membrane structure. The tea polyphenol-blended UHMWPE had no biological toxicity to human adipose-derived stem cells and effectively reduced bacteria-induced inflammation in vivo. These results indicate that tea polyphenol-blended UHMWPE is promising for joint replacement prostheses with multifunctionality to meet patient satisfaction.

Intrathecal versus local infiltration analgesia for pain control in total joint arthroplasty.

BACKGROUND: The purpose of this meta-analysis was to assess the efficacy of intrathecal morphine (ITM) analgesia and local infiltration analgesia (LIA) for pain control in total joint arthroplasty (TJA). METHODS: Embase, PubMed, the Cochrane Library, and Web of Science were systematically searched for randomized controlled trials (RCTs). All RCTs were comparing intrathecal analgesia and local infiltration analgesia in TJA. Primary outcomes were the visual analog scale (VAS) score with rest or mobilization up to 72 h. Secondary outcomes were the total morphine consumption, length of hospital stay, and morphine-related complications. RESULTS: Compared with the intrathecal analgesia group, the LIA group was associated with a reduction in VAS score with rest up to 72 h. Moreover, LIA was associated with a decrease in VAS score with mobilization at 6 h, 12 h, 48 h, and 72 h. Moreover, LIA significantly reduced total morphine consumption (weighted mean difference (WMD)  = - 15.37, 95% CI - 22.64 to - 8.83, P  = 0.000), length of hospital stay (WMD  =  - 1.39, 95% CI - 1.67 to - 1.11, P  = 0.000), and morphine-related complications (nausea and pruritus). CONCLUSIONS: Local infiltration provided superior analgesia and morphine-sparing effects within the first 72 h compared with ITM following TJA.

Oral Supplementation with Sucrosomial Ferric Pyrophosphate Plus L-Ascorbic Acid to Ameliorate the Martial Status: A Randomized Controlled Trial.

Altered martial indices before orthopedic surgery are associated with higher rates of complications and greatly affect the patient's functional ability. Oral supplements can optimize the preoperative martial status, with clinical efficacy and the patient's tolerability being highly dependent on the pharmaceutical formula. Patients undergoing elective hip/knee arthroplasty were randomized to be supplemented with a 30-day oral therapy of sucrosomial ferric pyrophosphate plus L-ascorbic acid. The tolerability was 2.7% among treated patients. Adjustments for confounding factors, such as iron absorption influencers, showed a relevant response limited to older patients (≥ 65 years old), whose uncharacterized Hb loss was averted upon treatment with iron formula. Older patients with no support lost -2.8 ± 5.1%, while the intervention group gained +0.7 ± 4.6% of circulating hemoglobin from baseline (p = 0.019). Gastrointestinal diseases, medications, and possible dietary factors could affect the efficacy of iron supplements. Future opportunities may consider to couple ferric pyrophosphate with other nutrients, to pay attention in avoiding absorption disruptors, or to implement interventions to obtain an earlier martial status optimization at the population level.

Has Self-reported Marijuana Use Changed in Patients Undergoing Total Joint Arthroplasty After the Legalization of Marijuana?

BACKGROUND: Marijuana use has become more accessible since its recent legalization in several states. However, its use in a total joint arthroplasty population to our knowledge has not been reported, and the implications of its use in this setting remain unclear. QUESTIONS/PURPOSES: We report (1) the self-reported use of marijuana in patients undergoing total joint arthroplasty both before and after its legalization; and (2) clinical and demographic factors associated with marijuana use in patients undergoing total joint arthroplasty. METHODS: One thousand records of patients undergoing primary total joint arthroplasty (500 consecutive before and 500 consecutive after the legalization of the commercial sale of marijuana in Colorado) were included for analysis. Preoperative medical history and physicals were retrospectively reviewed for self-reported and reasons (medicinal versus recreational) for use. Additionally, patient records were used to determine insurance type, age, gender, smoking status, history of substance abuse, preoperative narcotic use, alcohol intake, and the type of arthroplasty performed. RESULTS: Self-reported use after legalization dramatically increased from 1% (four of 500) to 11% (55 of 500) (odds ratio [OR], 15.3 [95% confidence interval, 5.5-42.6]; p < 0.001) after legalization. For those reporting use after legalization, 46% (25 of 55) of patients reported recreational use, 26% (14 of 55) medicinal use, 27% (15 of 55) did not report a reason for use, and 2% (one of 55) reported both recreational and medicinal use. Factors associated with use included younger age (with a 10-year mean difference between the groups [p < 0.001]), male gender (36 of 59 users [61%] versus 411 of 941 nonusers [44%]; OR, 2.02; p < 0.01), current smokers (22 of 59 users [37%] versus 54 of 941 [6%] nonusers; OR, 0.09; p < 0.01), a history of substance abuse (eight of 59 users [14%] versus 18 of 941 nonusers [2%]; OR, 8.04; p < 0.001), insurance type (Medicaid only, 28 of 59 [48%] users versus 56 of 941 [6%] nonusers; OR, 20.45; p < 0.01), and preoperative narcotic use (eight of 59 users [14%] versus 17 of 941 nonusers [2%]; OR, 2.4; p < 0.001). We did not find differences with regard to alcohol use, amount of alcohol consumption, or insurance types other than Medicaid. CONCLUSIONS: These results suggest the legalization of marijuana has led to either more users or more patients who are willing to report its use given the lack of legal ramifications. Despite these findings, the evidence to date precludes the use of marijuana postoperatively in patients undergoing total joint arthroplasty. Further investigation, ideally in a prospective randomized manner, should focus on opioid consumption, nausea, sleep patterns, and outcomes in patients using marijuana who are undergoing total joint arthroplasty before recommendations can be made for its use. LEVEL OF EVIDENCE: Level III, therapeutic study.

Procedure for single-stage implant retention for chronic periprosthetic infection using topical degradable calcium-based antibiotics.

INTRODUCTION: Surgical treatment using DAIR (debridement, systemic antibiotics, and implant retention) can lead to high rates of treatment success in cases of early periprosthetic joint infection (PJI) but can fail in late-onset cases. Supplementary local antibiotic therapy is not yet generally established and lacks evidence-based proof of efficacy. The aim of this study was to analyze DAIR outcomes in recurrent PJI cases and patients who are not suitable for a two-stage exchange, using additional degradable calcium-based antibiotics. METHODS: All patients fulfilled the Infectious Diseases Society of America (IDSA) guidelines for chronic late-onset PJI but were not suitable for a multistage procedure because of their individual operation risk. A total of 42 patients (mean age, 73 years) were treated using a single-stage algorithm consisting of DAIR, followed by implantation of degradable antibiotics chosen in accordance with an antibiogram. OSTEOSET® (admixed ceftriaxone/vancomycin/tobramycin) and Herafill-Gentamycin® were used as carrier systems. The follow-up period was 23 months (± SD, 10.3). The study is based on institutional review board (IRB) approval. RESULTS: The clinical entities were chronic PJI of the hip (45.2%), knee (28.6%), and knee arthrodesis (26.2%). The bacterial spectrum was composed of Staphylococcus epidermidis (29%), Staphylococcus aureus (21%), and Enterococcus faecalis (21%). 21.4% showed a combination of two or more bacteria. In 73.8%, permanent remission was achieved, while 11.9% showed chronic PJI under implant retention. Implant retention could be achieved in 85.7%. CONCLUSION: DAIR usually shows low levels of success in difficult-to-treat cases. However, we could demonstrate the successful treatment of patients with recurrent PJI (typically considered DAIR-inappropriate) using degradable antibiogram-based topical calcium-based antibiotics. Over 70% of the cases went to remission and over 85% of the implants could be retained.

American Joint Replacement Registry Risk Calculator Does Not Predict 90-day Mortality in Veterans Undergoing Total Joint Replacement.

BACKGROUND: The American Joint Replacement Registry (AJRR) Total Joint Risk Calculator uses demographic and clinical parameters to provide risk estimates for 90-day mortality and 2-year periprosthetic joint infection (PJI). The tool is intended to help surgeons counsel their Medicare-eligible patients about their risk of death and PJI after total joint arthroplasty (TJA). However, for a predictive risk model to be useful, it must be accurate when applied to new patients; this has yet to be established for this calculator. QUESTIONS/PURPOSES: To produce accuracy metrics (ie, discrimination, calibration) for the AJRR mortality calculator using data from Medicare-eligible patients undergoing TJA in the Veterans Health Administration (VHA), the largest integrated healthcare system in the United States, where more than 10,000 TJAs are performed annually. METHODS: We used the AJRR calculator to predict risk of death within 90 days of surgery among 31,214 VHA patients older than 64 years of age who underwent primary TJA; data was drawn from the Veterans Affairs Surgical Quality Improvement Project (VASQIP) and VA Corporate Data Warehouse (CDW). We then used VHA mortality data to evaluate the extent to which the AJRR calculator estimates distinguished individuals who died compared with those who did not (C-statistic), and graphically depicted the relationship between estimated risk and observed mortality (calibration). As a secondary evaluation of the calculator, a sample of 39,300 patients younger than 65 years old was assigned to the youngest age group available to the user (65-69 years) as might be done in real-world practice. RESULTS: C-statistics for 90-day mortality for the older samples were 0.62 (95% CI, 0.60-0.64) and for the younger samples they were 0.46 (95% CI, 0.43-0.49), suggesting poor discrimination. Calibration analysis revealed poor correspondence between deciles of predicted risk and observed mortality rates. Poor discrimination and calibration mean that patients who died will frequently have a lower estimated risk of death than surviving patients. CONCLUSIONS: For Medicare-eligible patients receiving TJA in the VA, the AJRR risk calculator had a poor performance in the prediction of 90-day mortality. There are several possible reasons for the model's poor performance. Veterans Health Administration patients, 97% of whom were men, represent only a subset of the broader Medicare population. However, applying the calculator to a subset of the target population should not affect its accuracy. Other reasons for poor performance include a lack of an underlying statistical model in the calculator's implementation and simply the challenge of predicting rare events. External validation in a more representative sample of Medicare patients should be conducted to before assuming this tool is accurate for its intended use. LEVEL OF EVIDENCE: Level I, diagnostic study.

Gabapentin Does Not Appear to Improve Postoperative Pain and Sleep Patterns in Patients Who Concomitantly Receive Regional Anesthesia for Lower Extremity Orthopedic Surgery: A Randomized Control Trial.

In recent years, gabapentin has gained popularity as an adjuvant therapy for the treatment of postoperative pain. Numerous studies have shown a decrease in pain score, even with immediate postoperative activity, which is significant for early post-op ambulation and regaining functionality sooner. However, studies have been in conclusive in patients undergoing lower extremity orthopedic surgery. For this reason, we hoped to study the effect of gabapentin on postoperative pain in patients undergoing total knee arthroplasty, total hip arthroplasty, or a hip fracture repair. This was done in the setting of ensuring adequate postoperative analgesia with regional blocks and opioid PCA, as is protocol at our institution. Given the sedative effects of gabapentin and the potential for improving postoperative sleep patterns, we also studied the drug's effect on this aspect of our patient's postoperative course. We utilized the Pittsburg Sleep Quality Index and Visual Analog Scale for pain to obtain a more objective standardized score amongst our study population. Our results indicate that gabapentin does not offer any additional relief in pain or improve sleep habits in patients who have received either a femoral or lumbar plexus block for lower extremity orthopedic surgery. This trial is registered with NCT01546857.

Predicting the Incremental Hospital Cost of Adverse Events Among Medicare Beneficiaries in the Comprehensive Joint Replacement Program During Fiscal Year 2014.

BACKGROUND: The Medicare program's Comprehensive Care for Joint Replacement (CJR) payment model places hospitals at financial risk for the treatment cost of Medicare beneficiaries (MBs) undergoing lower extremity joint replacement (LEJR). METHODS: This study uses Medicare Provider Analysis and Review File and identified 674,777 MBs with LEJR procedure during fiscal year 2014. Adverse events (death, acute myocardial infarction, pneumonia, sepsis or shock, surgical site bleeding, pulmonary embolism, mechanical complications, and periprosthetic joint infection) were studied. Multivariable regressions were modeled to estimate the incremental hospital cost of treating each adverse event. RESULTS: The risk-adjusted estimated hospital cost of treating adverse events varied from a high of $29,061 (MBs experiencing hip fracture and joint infection) to a low of $6308 (MBs without hip fracture that experienced pulmonary embolism). CONCLUSION: Avoidance of adverse events in the LEJR hospitalization will play an important role in managing episode hospital costs in the Comprehensive Care for Joint Replacement program.

Total Wrist Arthroplasty.

Total wrist arthroplasty (TWA), first performed in the late 19th Century, is still an infrequently used operation. It is most commonly indicated in patients with rheumatoid arthritis who have pan-carpal wrist involvement. It is an alternative to total wrist arthrodesis in patients who wish to preserve joint motion. Patients must lead a low-demand lifestyle and have failed non-operative measures. Complications are not insignificant and have been reported to be as high as 43%. Modern generation implants most often fail due to dislocation or loosening. Because wrist arthrodesis remains the gold standard treatment, particularly in patients with higher physical demands, it remains to be seen whether TWA will gain greater acceptance as prosthetic designs evolve.

Current Risk Adjustment and Comorbidity Index Underperformance in Predicting Post-Acute Utilization and Hospital Readmissions After Joint Replacements: Implications for Comprehensive Care for Joint Replacement Model.

OBJECTIVE: To compare the performances of 3 comorbidity indices, the Charlson Comorbidity Index, the Elixhauser Comorbidity Index, and the Centers for Medicare & Medicaid Services (CMS) risk adjustment model, Hierarchical Condition Category (HCC), in predicting post-acute discharge settings and hospital readmission for patients after joint replacement. METHODS: A retrospective study of Medicare beneficiaries with total knee replacement (TKR) or total hip replacement (THR) discharged from hospitals in 2009-2011 (n = 607,349) was performed. Study outcomes were post-acute discharge setting and unplanned 30-, 60-, and 90-day hospital readmissions. Logistic regression models were built to compare the performance of the 3 comorbidity indices using C statistics. The base model included patient demographics and hospital use. Subsequent models included 1 of the 3 comorbidity indices. Additional multivariable logistic regression models were built to identify individual comorbid conditions associated with high risk of hospital readmissions. RESULTS: The 30-, 60-, and 90-day unplanned hospital readmission rates were 5.3%, 7.2%, and 8.5%, respectively. Patients were most frequently discharged to home health (46.3%), followed by skilled nursing facility (40.9%) and inpatient rehabilitation facility (12.7%). The C statistics for the base model in predicting post-acute discharge setting and 30-, 60-, and 90-day readmission in TKR and THR were between 0.63 and 0.67. Adding the Charlson Comorbidity Index, the Elixhauser Comorbidity Index, or HCC increased the C statistic minimally from the base model for predicting both discharge settings and hospital readmission. The health conditions most frequently associated with hospital readmission were diabetes mellitus, pulmonary disease, arrhythmias, and heart disease. CONCLUSION: The comorbidity indices and CMS-HCC demonstrated weak discriminatory ability to predict post-acute discharge settings and hospital readmission following joint replacement.

Risk factors for blood transfusion after shoulder arthroplasty.

AIMS: Currently, there is little information about the need for peri-operative blood transfusion in patients undergoing shoulder arthroplasty. The purpose of this study was to identify the rate of transfusion and its predisposing factors, and to establish a blood conservation strategy. METHODS: We identified all patients who had undergone shoulder arthroplasty at our hospital between 1 January 2011 and 31 December 2013. The rate of transfusion was determined from the patient's records. While there were exceptions, patients typically underwent transfusion if they had a level of haemoglobin of < 7.5 g/dl if asymptomatic, < 9.0 g/dl if they had a significant cardiac history or symptoms of dizziness or light headedness. Multivariable regression analysis was undertaken to identify predictors of transfusion. High- and low-risk cohorts for transfusion were identified from a receiver operating characteristic (ROC) curve. RESULTS: Of 1174 shoulder arthroplasties performed on 1081 patients, 53 cases (4.5%) required transfusion post-operatively. Predictors of blood transfusion were a lower pre-operative haematocrit (p < 0.001) and shoulder arthroplasty undertaken for post-traumatic arthritis (p < 0.001). ROC analysis identified pre-operative haematocrit of 39.6% as a 90% sensitivity cut-off for transfusion. In total 48 of the 436 (11%) shoulder arthroplasties with a pre-operative haematocrit < 39.6% needed transfusion compared with five of the 738 (0.70%) shoulder arthroplasties with a haematocrit above this level. DISCUSSION: We found that transfusion was needed less frequently than previously described for shoulder arthroplasty. Patients with a pre-operative haematocrit < 39.6% should be advised that there is an increased risk for blood transfusion, while those with a haematocrit above this level are unlikely to require transfusion. TAKE HOME MESSAGE: The rate of transfusion after shoulder arthroplasty is under 5%, and those with a pre-operative haematocrit greater than or equal to 39.6% have a very low likelihood (< 1%) of requiring a transfusion.

Cathodic Electrical Stimulation Combined With Vancomycin Enhances Treatment of Methicillin-resistant Staphylococcus aureus Implant-associated Infections.

BACKGROUND: Effective treatments for implant-associated infections are often lacking. Cathodic voltage-controlled electrical stimulation has shown potential as a treatment of implant-associated infections of methicillin-resistant Staphylococcus aureus (MRSA). QUESTIONS/PURPOSES: The primary purpose of this study was to (1) determine if cathodic voltage-controlled electrical stimulation combined with vancomycin therapy is more effective at reducing the MRSA bacterial burden on the implant, bone, and synovial fluid in comparison to either treatment alone or no treatment controls. We also sought to (2) evaluate the histologic effects of the various treatments on the surrounding bone; and to (3) determine if the cathodic voltage-controlled electrical stimulation treatment had an effect on the mechanical properties of the titanium implant as a result of possible hydrogen embrittlement. METHODS: Thirty-two adult male Long-Evans rats (Harlan Laboratories, Indianapolis, IN, USA) with surgically placed shoulder titanium implants were infected with a clinical strain of MRSA (NRS70). One week after infection, eight animals received a treatment of cathodic voltage-controlled electrical stimulation at -1.8 V versus Ag/AgCl for 1 hour (STIM), eight received vancomycin twice daily for 1 week (VANCO), eight received the cathodic voltage-controlled electrical stimulation and vancomycin therapy combined (STIM + VANCO), and eight served as controls with no treatment (CONT). Two weeks after initial infection, the implant, bone, and synovial fluid were collected for colony-forming unit (CFU) enumeration, qualitative histological analysis by a pathologist blinded to the treatments each animal received, and implant three-point bend testing. RESULTS: The implant-associated CFU enumerated from the STIM + VANCO (mean, 3.7 × 10(3); SD, 6.3 × 10(3)) group were less than those from the CONT (mean, 1.3 × 10(6); SD, 2.8 × 10(6); 95% confidence interval [CI] of difference, -4.3 × 10(5) to -9.9 × 10(3); p < 0.001), STIM (mean, 1.4 × 10(6); SD, 2.0 × 10(6); 95% CI of difference, -2.1 × 10(6) to -1.8 × 10(3); p = 0.002), and VANCO (mean, 5.8 x 10(4); SD, 5.7 × 10(4); 95% CI of difference, -6.4 × 10(4) to -1.7 × 10(4); p < 0.001) group. The bone-associated CFU enumerated from the STIM + VANCO group (6.3 × 10(1); SD, 1.1 × 10(2)) were less than those from the CONT (mean, 2.8 × 10(5); SD, 4.8 × 10(5); 95% CI of difference, -9.4 × 10(4) to -5.0 × 10(3); p < 0.001) and STIM (mean, 2.6 × 10(4); SD, 2.5 × 10(4); 95% CI of difference, -4.1 × 10(4) to -1.6 × 10(3); p < 0.001) groups. The VANCO group (4.3 × 10(5); SD, 6.3 × 10(2)) also had lower bone-associated CFU as compared with the CONT (mean 95% CI of difference, -9.3 × 10(4) to -4.5 × 10(3); p < 0.001) and STIM (95% CI of difference, -4.0 × 10(4) to -1.5 × 10(3); p < 0.001) groups. In comparison to the synovial fluid CFU enumerated from the CONT group (mean, 3.3 × 10(4); SD, 6.0 × 10(4)), lower synovial CFU were reported for both the STIM + VANCO group (mean, 4.6 × 10(1); SD, 1.2 × 10(2); 95% CI of difference, -4.9 × 10(3) to -3.0 × 10(2); p < 0.001) and the VANCO group (mean, 6.8 × 10(1); SD, 9.2 × 10(1); 95% CI of difference, -4.9 × 10(3) to -2.8 × 10(2); p = 0.007). The histological analysis showed no discernable deleterious effects on the surrounding tissue as a result of the treatments. No brittle fracture occurred during mechanical testing and with the numbers available, no differences in implant flexural yield strength were detected between the groups. CONCLUSIONS: In this rodent model, cathodic voltage-controlled electrical stimulation combined with vancomycin is an effective treatment for titanium implant-associated infections showing greater than 99.8% reduction in bacterial burden on the implant, surrounding bone, and synovial fluid as compared with the controls and the stimulation alone groups. CLINICAL RELEVANCE: Cathodic voltage-controlled electrical stimulation combined with vancomycin may enable successful treatment of titanium orthopaedic implant-associated infections with implant retention. Future studies will focus on optimization of the stimulation parameters for complete eradication of infection and the ability to promote beneficial host tissue responses.

Patient and procedure-specific risk factors for deep infection after primary shoulder arthroplasty.

BACKGROUND: Deep infection after shoulder arthroplasty is a diagnostic and therapeutic challenge. The current literature on this topic is from single institutions or Medicare samples, lacking generalizability to the larger shoulder arthroplasty population. QUESTIONS/PURPOSES: We sought to identify (1) patient-specific risk factors for deep infection, and (2) the pathogen profile after primary shoulder arthroplasty in a large integrated healthcare system. METHODS: A retrospective cohort study was conducted. Of 4528 patients identified, 320 had died and 302 were lost to followup. The remaining 3906 patients had a mean followup of 2.7 years (1 day-7 years). The study endpoint was the diagnosis of deep infection, which was defined as revision surgery for infection supported clinically by more than one of the following criteria: purulent drainage from the deep incision, fever, localized pain or tenderness, a positive deep culture, and/or a diagnosis of deep infection made by the operating surgeon based on intraoperative findings. Risk factors evaluated included age, sex, race, BMI, diabetes status, American Society for Anesthesiologists (ASA) score, traumatic versus elective procedure, and type of surgical implant. For patients with deep infections, we reviewed the surgical notes and microbiology records for the pathogen profile. Multivariable Cox regression models were used to evaluate the association of risk factors and deep infection. Adjusted hazard ratios and 95% CI are presented. RESULTS: With every 1-year increase in age, a 5% (95% CI, 2%-8%) lower risk of infection was observed. Male patients had a risk of infection of 2.59 times (95% CI, 1.27-5.31) greater than female patients. Patients undergoing primary reverse total shoulder arthroplasty had a 6.11 times (95% CI, 2.65-14.07) greater risk of infection compared with patients having primary unconstrained total shoulder arthroplasty. Patients having traumatic arthroplasties were 2.98 times (95% CI, 1.15-7.74) more likely to have an infection develop than patients having elective arthroplasties. BMI, race, ASA score, and diabetes status were not associated with infection risk (all p > 0.05). Propionibacterium acnes was the most commonly cultured organism, accounting for 31% of isolates. CONCLUSIONS: Younger, male patients are at greater risk for deep infection after primary shoulder arthroplasty. Reverse total shoulder arthroplasty and traumatic shoulder arthroplasties also carry a greater risk for infection. Propionibacterium acnes was the most prevalent pathogen causing infection in our primary shoulder arthroplasty population. LEVEL OF EVIDENCE: Level II, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.

How has the introduction of new bearing surfaces altered the biological reactions to byproducts of wear and modularity?

BACKGROUND: Biological responses to wear debris were largely elucidated in studies focused on conventional ultrahigh-molecular-weight polyethylene (UHMWPE) and some investigations of polymethymethacrylate cement and orthopaedic metals. However, newer bearing couples, in particular metal-on-metal but also ceramic-on-ceramic bearings, may induce different biological reactions. QUESTIONS/PURPOSES: Does wear debris from the newer bearing surfaces result in different biological responses compared with the known responses observed with conventional metal-on-UHMWPE bearings? METHODS: A Medline search of articles published after 1996 supplemented by a hand search of reference lists of included studies and relevant conference proceedings was conducted to identify the biological responses to orthopaedic wear debris with a focus on biological responses to wear generated from metal-on-highly crosslinked polyethylene, metal-on-metal, ceramic-on-ceramic, and ceramic-on-polyethylene bearings. Articles were selected using criteria designed to identify reports of wear debris particles and biological responses contributing to prosthesis failure. Case reports and articles focused on either clinical outcomes or tribology were excluded. A total of 83 papers met the criteria and were reviewed in detail. RESULTS: Biological response to conventional UHMWPE is regulated by the innate immune response. It is clear that the physical properties of debris (size, shape, surface topography) influence biological responses in addition to the chemical composition of the biomaterials. Highly crosslinked UHMWPE particles have the potential to alter, rather than eliminate, the biological response to conventional UHMWPE. Metal wear debris can generate elevated plasma levels of cobalt and chromium ions. These entities can provoke responses that extend to the elicitation of an acquired immune response. Wear generated from ceramic devices is significantly reduced in volume and may provide the impression of an "inert" response, but clinically relevant biological reactions do occur, including granulomatous responses in periprosthetic tissues. CONCLUSIONS: The material composition of the device, the physical form of the debris, and disease pathophysiology contribute to complex interactions that determine the outcome to all wear debris. Metal debris does appear to increase the complexity of the biological response with the addition of immunological responses (and possibly direct cellular cytotoxicity) to the inflammatory reaction provoked by wear debris in some patients. However, the introduction of highly crosslinked polyethylene and ceramic bearing surfaces shows promising signs of reducing key biological mechanisms in osteolysis.

Developing a pathway for high-value, patient-centered total joint arthroplasty.

BACKGROUND: Total joint arthroplasty (TJA) is one of the most widely performed elective procedures; however, there are wide variations in cost and quality among facilities where the procedure is performed. QUESTIONS/PURPOSES: The purposes of this study were to (1) develop a generalizable clinical care pathway for primary TJA using inputs from clinical, academic, and patient stakeholders; and (2) identify system- and patient-level processes to provide safe, effective, efficient, and patient-centered care for patients undergoing TJA. METHODS: We used a combination of quantitative and qualitative methods to design a care pathway that spans 14 months beginning with the presurgical office visit and concluding 12 months after discharge. We derived care suggestions from interviews with 16 hospitals selected based on readmission rates, cost, and quality (n = 10) and author opinion (n = 6). A 32-member multistakeholder panel refined the pathway during a 1-day workshop. Participants were selected based on leadership in orthopaedic (n = 4) and anesthesia (n = 1) specialty societies; involvement in organizations specializing in safety and high reliability care (n = 3), lean production/consumption of care (n = 3), and patient experience of care (n = 3); membership in an interdisciplinary care team of a hospital selected for interviewing (n = 8); recent receipt of a TJA (n = 1); and participation in the pathway development team (n = 9). RESULTS: The care pathway includes 40 suggested processes to improve care, 37 techniques to reduce waste, and 55 techniques to improve communication. Central themes include standardization and process improvement, interdisciplinary communication and collaboration, and patient/family engagement and education. Selected recommendations include standardizing care protocols and staff roles; aligning information flow with patient and process flow; identifying a role accountable for care delivery and communication; managing patient expectations; and stratifying patients into the most appropriate care level. CONCLUSIONS: We developed a multidisciplinary clinical care pathway for patients undergoing TJA based on principles of high-value care. The pathway is ready for clinical testing and context-specific adaptation. LEVEL OF EVIDENCE: Level V, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Frequent use of blood-saving measures in elective orthopaedic surgery: a 2012 Dutch blood management survey.

BACKGROUND: Blood loss in hip and knee arthroplasties may necessitate allogeneic blood transfusions. Different blood-saving measures (BSMs) were introduced to reduce these transfusions. Purpose of the present study was to assess the frequency of BSM use, stratified by type and hospital setting of orthopaedic departments in the Netherlands. METHODS: An internet-based questionnaire was sent to all heads of orthopaedic departments of Dutch hospitals and private clinics (n = 99). Questions were asked on how often BSMs were used, reported on a 5-point Likert scale (never, almost never, regularly, almost always, always). In addition there were questions about discontinuation of anticoagulants preoperatively, the number of annually performed arthroplasties (size) and hospital setting. RESULTS: The survey was completed by 81 (82%) departments. BSMs used frequently (regularly, almost always, always) were erythropoietine (EPO), with 55 (68%) departments being frequent users; acute normovolemic hemodilution, used frequently in 26 (32%) departments; cell saver in 25 (31%) and postoperative drainage and re-infusion in 56 (69%) departments. When compared by size, frequent EPO use was more common in large departments (with 22 (88%) large departments being frequent users versus 13 (63%) small departments and 16 (55%) intermediate departments, p = 0.03). No differences by size or type were observed for other BSMs. CONCLUSIONS: Compared with previous survey's there is a tremendous increase in use of BSMs. EPO and autologous blood salvage techniques are the most often used modalities. Costs might be saved if use of non-cost-effective BSMs is stopped.

Novel oral anticoagulants for thromboprophylaxis after orthopaedic surgery.

The direct thrombin inhibitor, dabigatran, and the selective factor Xa inhibitors, rivaroxaban and apixaban, are new oral anticoagulants that are approved in many countries for prevention of venous thromboembolism in patients undergoing elective hip or knee arthroplasty. All have a rapid onset of action, a low potential for food and drug interactions and a predictable anticoagulant effect that obviates the need for routine coagulation monitoring. These agents offer a convenient alternative to conventional anticoagulant drug regimens, including parenteral low-molecular-weight heparins and fondaparinux, and oral adjusted-dose vitamin K antagonists, for the prevention of venous thromboembolism in this surgical setting. This review summarizes the pharmacology, clinical trial results, bleeding risk and practical use of these new oral anticoagulants in clinical orthopaedic practice. Potential issues to be considered when using these oral anticoagulants include renal impairment, potential drug interactions, neuraxial anaesthesia and management of bleeding.

Commonalities, differences, and challenges with patient-derived outcome measurement tools: function/activity scales.

BACKGROUND: There is a critical need to evaluate the success of orthopaedic treatments through valid outcome measures. Previous attempts to express patient outcomes using a single aggregate score led to scores that were ambiguous, often insensitive to change, and poorly correlated with the patient's assessment of the outcome of surgical procedures. WHERE ARE WE NOW?: Numerous patient-reported outcome measurement tools have been developed for assessment of patients' level of activity and functional status, especially after joint arthroplasty. However, most tools assume an idealized set of prescribed activities independent of the age, activity level, and lifestyle of each individual. Few instruments are designed to capture the priorities of individual patients, especially those involved in high-demand sporting and recreational activities. WHERE DO WE NEED TO GO?: We need valid outcome measures that provide a meaningful, individualized assessment of the functional status of each patient, taking into account the lifestyle and expectation of each individual. This advance in outcome measurement will allow clinicians to individualize treatment and provide patients with an accurate estimate of the outcome of alternative treatments and procedures. HOW DO WE GET THERE?: Much more comprehensive information is needed to characterize the activities, abilities, and physical aspirations of individual patients. This could form a database for the development of predictive models relating individual characteristics to functional outcomes. Statistical tools are needed to minimize the burden on patients in completing questionnaires to access predictive data and to ensure that all outcome assessments are psychometrically valid.