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Racial and ethnic disparities in hospital readmissions following total joint arthroplasty present opportunities for reducing cost and improving health equity. Despite efforts to reduce readmissions following total joint arthroplasty in the general population, no studies have documented the impact of these efforts on racial and ethnic disparities in total joint arthroplasty readmissions. The purpose of this study was to determine whether comprehensive efforts to reduce hospital readmissions following total joint arthroplasty have impacted racial and ethnic disparities in readmission rates during the period from 2005 to 2015.We conducted a retrospective analysis comparing patients readmitted and not readmitted to the hospital within 30 days of a total joint arthroplasty by estimating logistic regression models for clustered data using generalized estimating equations (GEEs) in R. Connecticut hospital discharge data for patients admitted for International Classification of Diseases, Ninth Revision (ICD-9) procedure codes 81.51 and 81.54 (Current Procedural Terminology [CPT] codes 27130 and 27447) during the 2005 to 2015 U.S. Centers for MedicareMedicaid Services (CMS) fiscal years were analyzed. Models included quadratic terms to capture nonlinear time trends in readmissions, as well as terms for the statistical interaction between race or ethnicity and both the linear and quadratic time trends in predicting the odds of readmission.There were 102,510 total admissions to Connecticut hospitals for total joint arthroplasty from 2005 to 2015. The 30-day (all-cause) readmission rate declined from 5.1% in 2005 to 3.6% in 2015, with a steeper downward trend observed from 2009 to 2015. The results from logistic models indicated that black patients (odds ratio [OR], 1.68; p0.0001) and Hispanic patients (OR, 1.48; p0.0001) were significantly more likely to be readmitted within 30 days of discharge following a total joint arthroplasty than white patients over the study period. The significant interaction of black race and the quadratic time trend in models capturing nonlinear trends in readmission over time indicated that the readmission rates for black patients increased compared with those for white patients from 2005 through 2008 and decreased relative to those for white patients from 2009 to 2015 (OR, 0.24; p = 0.030).Data from Connecticut hospitals show that 30-day readmissions following a total joint arthroplasty declined by 1.5 percentage points from 2005 to 2015, and that this decline was much more pronounced among black patients, resulting in the narrowing of racial disparities in readmission following a surgical procedure.Racial and ethnic minorities have historically been at increased risk for complications and readmission following hospital-based surgical care. This analysis of readmission following total joint arthroplasty reveals that such disparities are remediable and should foster further research on the primary drivers of and remedies for readmission disparities.

Summary Objective We aimed to directly quantify the zone-specific evolution in morphology of collagen fibers and networks in human cartilage during the progression of early osteoarthritis. Collagen fibers exhibit depth-dependent orientations and diameters crucial to their mechanical roles. Cartilage degenerates in osteoarthritis, affecting the morphology of the collagen network and ultimately the intra-tissue mechanics. Design We obtained specimens of human cartilage from healthy human knees ( n = 3 ) and from total knee arthroplasties ( n = 5 ). We utilized TEM and custom image analyses to visualize and quantify distributions in principal orientation, dispersion (about the principal orientation), and diameter of collagen fibers in the early grades of OA within each through-thickness zone. We then used histological and statistical analyses to probe for significant changes in the zone-specific evolution in collagen-network morphology as a function of Osteoarthritis Research Society International (OARSI) grade. Results Dispersion in the alignment of collagen fibers increased with progression of early OA in both the superficial and deep zones, and decreased in the middle zone, while principal orientation did not change significantly. The non-normal and right-skewed distributions in fiber diameters did not evolve with the progression of OA. Conclusions We provide the research community with quantitative data (1) on the through-thickness morphology of collagen in healthy cartilage and (2) on the evolution of through-thickness morphology of collagen with progressing early OA. Such quantitative data facilitate an improved mechanistic understanding of the progression of OA, and may facilitate identifying image-based biomarkers and treatment targets, and ultimately finding clinical interventions for OA.

Summary Objective Given the structural changes associated with the progression of Osteoarthritis (OA), we hypothesized that patterns of through-thickness, large-strain shear evolve with early-stage OA. We therefore aimed to determine whether and how patterns of shear strains change during early-stage OA to 1) gain insight into the progression of OA by quantifying changes in local deformations; 2) gauge the potential of patterns in shear strain to serve as image-based biomarkers of early-stage OA; and 3) provide high-resolution, through-thickness data for proposing, fitting, and validating constitutive models for cartilage. Design We completed displacement-driven, large-strain shear tests (5, 10, 15%) on 44 specimens of variably advanced osteoarthritic human articular cartilage as determined by both Osteoarthritis Research Society International (OARSI) grade and PLM-CO score. We recorded the through-thickness deformations with a stereo-camera system and processed these data using digital image correlation (DIC) to determine full-thickness patterns of strains and relative zonal recruitments, i.e., the average shear strain in a through-thickness zone weighted by its relative thickness and normalized by the applied strain. Results We observed three general shapes for the curves of averaged through-thickness, Green–Lagrange shear strains during progression of OA. We also observed that during the progression of OA only the deep zone is recruited differently under shear in a statistically significant way. Conclusions We propose that changes in through-thickness patterns of shear strain could provide sensitive biomarkers for early clinical detection of OA. The relative zonal recruitment of the deep zone decreases with progressing OA (OARSI grade) and microstructural remodeling (PLM-CO score), which do not consistently affect recruitment of the superficial and middle zones.

The relationship between patient expectations and patient-reported outcomes (PROs) in total hip arthroplasty (THA) patients is controversial. The purpose of this study was to examine the impact of preoperative patient expectations on postoperative PROs and patient satisfaction.This was a prospective multicenter observational cohort study of primary THA patients. Preoperatively, patients completed Hospital for Special Surgery (HSS) Hip Replacement Expectations Survey (expectations), 12 item Short Form Survey (SF-12), University of California, Los Angeles (UCLA) activity score, and Hip Disability and Osteoarthritis Score (HOOS). Postoperatively at 6 months and 1 year, patients completed the Hospital for Special Surgery Hip Replacement Fulfillment of Expectations Survey (fulfillment of expectations), a satisfaction survey, and the same PROs as preoperatively. Stepwise multivariate regression models were created.A total of 207 patients were enrolled. Follow-up rate was 91% at 6 months and 92% at 1 year. Being employed and lower baseline HOOS predicted higher expectations (employment status: B = -7.5, P = .002; HOOS: B = -0.27, P = .002). Higher preoperative expectations predicted greater improvements in UCLA activity, SF-12 physical component score, and HOOS at 6 months (UCLA activity: B = 0.03, P = .001; SF-12 physical component score: B = 0.15, P = .001; HOOS: B = 0.20; P = .008) and UCLA activity at 1 year (B = 0.02, P = .004). Furthermore, higher expectations predicted higher postoperative satisfaction and fulfillment of expectations at 6 months (satisfaction: B = 0.21, P.001; fulfillment of expectations: B = 0.30, P.001) and higher fulfillment of expectations at 1 year (B = 0.17, P = .006).In patients undergoing THA, being employed and worse preoperative hip function predict of higher preoperative expectations of surgery. Higher expectations predict greater improvement in PROs, greater patient satisfaction, and the fulfillment of expectations. These findings can be used to guide patient counseling and shared decision making preoperatively.

© 2017 Elsevier Ltd Background Reoperation rates are high after surgery for hip fractures. We investigated the effect of a sliding hip screw versus cancellous screws on the risk of reoperation and other key outcomes. Methods For this international, multicentre, allocation concealed randomised controlled trial, we enrolled patients aged 50 years or older with a low-energy hip fracture requiring fracture fixation from 81 clinical centres in eight countries. Patients were assigned by minimisation with a centralised computer system to receive a single large-diameter screw with a side-plate (sliding hip screw) or the present standard of care, multiple small-diameter cancellous screws. Surgeons and patients were not blinded but the data analyst, while doing the analyses, remained blinded to treatment groups. The primary outcome was hip reoperation within 24 months after initial surgery to promote fracture healing, relieve pain, treat infection, or improve function. Analyses followed the intention-to-treat principle. This study was registered with ClinicalTrials.gov, number NCT00761813. Findings Between March 3, 2008, and March 31, 2014, we randomly assigned 1108 patients to receive a sliding hip screw (n=557) or cancellous screws (n=551). Reoperations within 24 months did not differ by type of surgical fixation in those included in the primary analysis: 107 (20%) of 542 patients in the sliding hip screw group versus 117 (22%) of 537 patients in the cancellous screws group (hazard ratio [HR] 0·83, 95% CI 0·63–1·09; p=0·18). Avascular necrosis was more common in the sliding hip screw group than in the cancellous screws group (50 patients [9%] vs 28 patients [5%]; HR 1·91, 1·06–3·44; p=0·0319). However, no significant difference was found between the number of medically related adverse events between groups (p=0·82; appendix); these events included pulmonary embolism (two patients [

We aimed to identify significant demographic, preoperative comorbidity and surgical predictors for major complications for use in the development of a risk prediction tool for a well-defined population as Total Joint Arthroplasty (TJA) patients. Data on 5314 consecutive patients who underwent primary total hip or knee arthroplasty from October 1, 2008 through September 30, 2011 at a single institution were used in a multivariate regression analysis. The overall incidence of a primary endpoint (reoperation during same admission, extended length of stay, and 30-day readmission) was 3.8%. Significant predictors include certain preexisting genitourinary, circulatory and respiratory conditions; ASA>2; advanced age and prolonged operating time. Mental health conditions demonstrate a strong predictive effect for subsequent serious complication(s) in TJA patients and should be included in a risk-adjustment tool.

Background The relationship between patient expectations, patient-reported outcomes (PROs), and satisfaction in total knee arthroplasty (TKA) patients is not well understood. Methods We prospectively evaluated patients who underwent primary TKA at 4 institutions. Demographics were collected. Preoperatively, patients completed the Hospital for Special Surgery Knee Replacement Expectations Survey (HSS-KRES), SF-12, UCLA activity, and Knee Disability and Osteoarthritis Score. At 6 months and 1 year postoperatively, patients completed the Hospital for Special Surgery Knee Replacement Fulfillment of Expectations Survey (HSS-KRFES), a satisfaction survey, and PROs. Step-wise multivariate regression models were created. Results Eighty-three patients were enrolled. At 6 months and 1 year postoperatively, the follow-up rate was 84.3% and 92.7%, respectively. No demographics or preoperative PROs were predictive of HSS-KRES. Preoperative HSS-KRES did not predict postoperative satisfaction, but higher HSS-KRES predicted higher HSS-KRFES at 1 year, greater improvement in UCLA activity at 6 months and 1 year, and SF-12 Physical Composite Scale and Knee Disability and Osteoarthritis Score at 6 months. Higher HSS-KRFES predicted higher satisfaction at 6 months and 1 year. Conclusion In TKA patients, preoperative expectations are not influenced by patient demographics or preoperative function. Higher preoperative expectations predict greater postoperative improvement in PROs and fulfillment of expectations. These findings highlight the importance of preoperative patient expectations on postoperative outcome.

The growth of consumer-directed health plans has sparked increased demand for information regarding the cost and quality of healthcare services, including total joint arthroplasty (TJA). However, the factors that influence patients' choice of provider when pursuing elective orthopaedic care, such as TJA, are poorly understood.We evaluated the factors patients consider when selecting an orthopaedic surgeon and hospital for TJA.Two hundred fifty-one patients who sought treatment from either an academic or community-based orthopaedic practice for primary TJA completed a 37-item survey using a 5-point Likert scale rating ("unimportant" to "very important") regarding seven established clinical and nonclinical dimensions of care patients considered when selecting a provider and hospital.Patients rated physician manner (average Likert, 4.7) and physician quality (eg, outcomes) (average Likert, 4.6) as most important in their selection of surgeon and hospital for TJA. Despite the expressed importance of surgeon and hospital quality, only 46% of patients were able to find useful information to compare outcomes among surgeons, and 47% for hospitals that perform TJA.Our findings suggest physician manner and surgical outcomes are the most important considerations for patients when choosing a provider for elective TJA. Cost sharing is the least important criterion patients considered. Patients expressed high motivation to seek out provider quality information but indicated accessible and actionable sources of information are lacking. Future efforts should be directed at developing clinically relevant, easily interpretable, objective, risk-adjusted measures of physician and hospital quality.

To prospectively compare the functional outcome associated with cemented and uncemented hemiarthroplasty.Prospective randomized control trial.University-affiliated level 1 trauma center.All individuals designated for hemiarthroplasty, older than 55 years, with a nonpathologic displaced femoral neck fracture and the ability to ambulate 10 feet independently before injury [269 patients (274 hips) presented with displaced femoral neck fracture, 130 patients (48.3%) enrolled, and 5 patients (3.8%) withdrew].Hip hemiarthroplasty with a cemented femoral prosthesis (VerSys LD/Fx; Zimmer, Warsaw, IN) or an uncemented component (VerSys Beaded FullCoat; Zimmer, Warsaw, IN).Instrumental Activities of Daily Living and Physical Activities of Daily Living scales (Older Americans Resources and Services Instrument) and the Energy/Fatigue Scale.No statistically significant differences were present in the groups' preoperative or intraoperative characteristics, including American Society of Anesthesiologists grade, operative time, anesthesia time, use of perioperative β-blockers, estimated blood loss, or the rate of intraoperative fracture. Postoperatively, no difference was found in hemoglobin level, transfusion rate, discharge disposition, or acute complication rate. At 30-day, 60-day, and 1-year follow-ups, no clinically or statistically significant differences were found in mortality, disposition, need for assistance with ambulation, Older Americans Resources and Services Activities of Daily Living subscales, or the Energy/Fatigue Scale.In the treatment of nonpathologic displaced femoral neck fractures, the use of cemented and uncemented femoral components is associated with similar functional outcome at 1 year. Practitioners may inform their clinical decisions using these equally good results.Therapeutic Level II. See page 128 for a complete description of levels of evidence.

This guideline supersedes a prior one from 2007 on a similar topic. The work group evaluated the available literature concerning various aspects of patient screening, risk factor assessment, and prophylactic treatment against venous thromboembolic disease (VTED), as well as the use of postoperative mobilization, neuraxial agents, and vena cava filters. The group recommended further assessment of patients who have had a previous venous thromboembolism but not for other potential risk factors. Patients should be assessed for known bleeding disorders, such as hemophilia, and for the presence of active liver disease. Patients who are not at elevated risk of VTED or for bleeding should receive pharmacologic prophylaxis and mechanical compressive devices for the prevention of VTED. The group did not recommend specific pharmacologic agents and/or mechanical devices. The work group recommends, by consensus opinion, early mobilization for patients following elective hip and knee arthroplasty. The use of neuraxial anesthesia can help limit blood loss but was not found to affect the occurrence of VTED. No clear evidence was established regarding whether inferior vena cava filters can prevent pulmonary embolism in patients who have a contraindication to chemoprophylaxis and/or known VTED.

Item does not contain fulltext BACKGROUND: The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been extensively evaluated in groups of patients with osteoarthritis, yet not in patients with a femoral neck fracture. This study aimed to determine the reliability, construct validity, and responsiveness of the WOMAC compared with the Short Form-12 (SF-12) and the EuroQol 5D (EQ-5D) questionnaires for the assessment of elderly patients with a femoral neck fracture. METHODS: Reliability was tested by assessing the Cronbach alpha. Construct validity was determined with the Pearson correlation coefficient. Change scores were calculated from ten weeks to twelve months of follow-up. Standardized response means and floor and ceiling effects were determined. Analyses were performed to compare the results for patients less than eighty years old with those for patients eighty years of age or older. RESULTS: The mean WOMAC total score was 89 points before the fracture in the younger patients and increased from 70 points at ten weeks to 81 points at two years postoperatively. In the older age group, these scores were 86, 75, and 78 points. The mean WOMAC pain scores before the fracture and at ten weeks and two years postoperatively were 92, 76, and 87 points, respectively, in the younger age group and 92, 84, and 93 points in the older age group. Function scores were 89, 68, and 79 points for the younger age group and 84, 71, and 73 points for the older age group. The Cronbach alpha for pain, stiffness, function, and the total scale ranged from 0.83 to 0.98 for the younger age group and from 0.79 to 0.97 for the older age group. Construct validity was good, with 82% and 79% of predefined hypotheses confirmed in the younger and older age groups, respectively. Responsiveness was moderate. No floor effects were found. Moderate to large ceiling effects were found for pain and stiffness scales at ten weeks and twelve months in younger patients (18% to 36%) and in the older age group (38% to 53%). CONCLUSIONS: The WOMAC showed good reliability, construct validity, and responsiveness in both age groups of elderly patients with a femoral neck fracture who had been physically and mentally fit before the fracture. The instrument is suitable for use in future clinical studies in these populations. CLINICAL RELEVANCE: The results are based on two clinical trials. The questionnaires used concern pure, clinically relevant issues (ability to walk, climb stairs, etc.). Moreover, the results can be used for future research comparing clinical outcomes (or treatments) for populations with a femoral neck fracture.

Osseointegrated implants are a common therapy for the elderly population as lifespan increases. Understanding the effects of age and sex on osseointegration is important for successful implant therapy. Therefore, the response of primary human osteoblasts (HOB) to implant materials was studied. HOBs were obtained by outgrowth of cells from bone from orthopaedic procedures and categorized as Young (Y),15; Middle (M), 30-50; and Old (O),60 years old. Initially the HOB phenotype was determined on tissue culture plastic. Alkaline phosphatase (ALP) staining and activity were significantly increased in HOBs from older patients. Message levels of type I collagen (COL), bone sialoprotein (BSP) and ALP were significantly higher (from 2.3- to 3.8-fold) in Y subjects compared to M and O patients at 2 weeks. Studies of the response of HOBs to implant materials were undertaken using Ti-6Al-4V disks prepared in a manner similar to orthopaedic implants. A 1.4-fold (p0.05) increase in cell attachment was found in HOBs from Y compared with O in female subjects but not in male subjects. Cell proliferation at 24 h was not significantly different by age or sex, nor was DNA content different at 2 and 4 weeks. Mineralization in HOB-implant cultures was 2.3-fold higher in Y than in O, and 1.7-fold higher in Y compared to M HOBs from female but not male subjects at 4 weeks. Northern blot and RT-PCR analysis at 2 weeks of culture showed significantly higher levels (1.6-2.3-fold) of COL, BSP, and osteocalcin (OC) mRNAs in Y HOBs compared to M and O HOBs from female subjects. We conclude that human osteoblasts from older female patients have a decreased ability to form bone on implants.

Background: Patients undergoing total hip or total knee arthroplasty have risks that include venous thromboembolism. The American Academy of Orthopaedic Surgeons has promulgated guidelines for the preoperative assessment of patients with the primary objective of preventing pulmonary embolism. We aimed to evaluate and establish the utility of the first-generation American Academy of Orthopaedic Surgeons guidelines for the prophylaxis of venous thromboembolism in patients undergoing total joint arthroplasty at a single institution. Methods: A prospective analysis of 3289 consecutive patients managed with total hip or total knee arthroplasty at the Connecticut Joint Replacement Institute between June 1, 2009, and April 30, 2011, was conducted. Data on age, sex, body mass index, American Society of Anesthesiologists classification, and a personal or family history of blood clots requiring long-term warfarin use were analyzed, as were data on a personal history of a malignant tumor, a bleeding disorder, gastrointestinal bleeding, or a hemorrhagic cerebrovascular accident. All patients were managed prophylactically with a specific algorithm based on the American Academy of Orthopaedic Surgeons guidelines. All of the patients were mobilized on postoperative day one, and pneumatic foot-pump compression was used for the duration of the hospitalization. Results: Thirty-six major venous thromboembolic events were documented with Doppler ultrasound or computed tomography angiography, for a ninety-day incidence of 1.1% (95% confidence interval, 0.8% to 1.5%). A personal history of blood clots was significantly associated with a blood clot in the proximal part of the thigh or a pulmonary embolism, but a family history of blood clots and a personal history of a malignant tumor did not show a significant relationship with venous thromboembolism. The ninety-day incidence of venous thromboembolism was significantly different between total hip arthroplasty patients (0.56%; 95% confidence interval, 0.30% to 1.15%) and total knee arthroplasty patients (1.46%; 95% confidence interval, 1.01% to 2.10%). The risk was greater in high-risk total knee arthroplasty patients compared with high-risk total hip arthroplasty patients despite comparable prophylaxis with enoxaparin sodium for twenty-eight days. Conclusions: The prospective use of the first-generation American Academy of Orthopaedic Surgeons guidelines resulted in a low incidence of clinically important thromboembolic events in total hip and total knee arthroplasty patients. When properly used in these patients, the guidelines to minimize adverse outcomes are executable and effective. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Twenty-five mongrel dogs were studied using implantation of autograft, fresh-frozen allograft, and beta-tricalcium phosphate around a porous-coated chrome-cobalt plug in the distal femoral metaphysis; interference-fit and overreamed control specimens were also studied. Over the course of this 4-month study, bone ingrowth through the grouting materials into the center plug was noted for autologous, allograft, and ceramic specimens. Quantitatively, in terms of push-out strength and histology, there were no significant differences between grafted groups; significantly higher push-out strengths were attained in each grafted subgroup compared with nongrafted, overreamed control subjects. In the setting of uncemented revision total hip arthroplasty, bone-grafting is frequently required. Because of the limited availability of autogenous bone and the potential liabilities of allograft material, attention has been given to bone substitutes. On the basis of this preliminary study, bone ingrowth into a porous metal substrate has been documented to occur through autograft, allograft, or ceramic grouting agents. Within the limits of this nonloaded experimental model, it appears that these materials are comparable in terms of their osteoconductive capability. Even in the optimal laboratory situation, bone ingrowth does not appear to occur in a canine model across a nongrafted 2-mm gap with regularity over a 16-week period.

Background: We studied the efficacy of local infiltration analgesia in surgical wounds with 0.2% ropivacaine (50 mL), ketorolac (15 mg), and adrenaline (0.5 mg) compared with that of local infiltration analgesia combined with continuous infusion of 0.2% ropivacaine as a method of pain control after total hip arthroplasty. We hypothesized that as a component of multimodal analgesia, local infiltration analgesia followed by continuous infusion of ropivacaine would result in reduced postoperative opioid consumption and lower pain scores compared with infiltration alone, and that both of these techniques would be superior to placebo. Methods: In this prospective, double-blind, placebo-controlled study, 105 patients were randomized into three groups: Group I, in which patients received infiltration with ropivacaine, ketorolac, and adrenaline followed by continuous infusion of 0.2% ropivacaine at 5 mL/hr; Group II, in which patients received infiltration with ropivacaine, ketorolac, and adrenaline followed by continuous infusion of saline solution at 5 mL/hr; and Group III, in which patients received infiltration with saline solution followed by continuous infusion of saline solution at 5 mL/hr. All patients received celecoxib, pregabalin, and acetaminophen perioperatively and patient-controlled analgesia; surgery was performed under general anesthesia. Before wound closure, the tissues and periarticular space were infiltrated with ropivacaine, ketorolac, and adrenaline or saline solution and a fenestrated catheter was placed. The catheter was attached to a pump prefilled with either 0.2% ropivacaine or saline solution set to infuse at 5 mL/hr. The primary outcome measure was postoperative opioid consumption and the secondary outcome measures were pain scores, adverse side effects, and patient satisfaction. Results: There were no differences between groups in the administration of opioids in the operating room, in the recovery room, or on the surgical floor. The pain scores on recovery room admission and discharge and the floor were low and similar between groups. There were no differences in the incidence of adverse side effects among groups. Patient satisfaction with pain management was similar in all groups. Conclusions: Local infiltration analgesia alone or followed by continuous infusion of ropivacaine as part of multimodal analgesia provides no additional analgesic benefit or reduction in opioid consumption compared with placebo following total hip arthroplasty. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

As early as 1956, laboratory investigations into the carcinogenicity of modern dental and orthopaedic alloys were undertaken. Such studies were prompted by the observation that workers, particularly in nickel and chromate refining, had increased risks of nasal and lung tumors. For the past 25 years, sporadic case reports have documented the development of malignant neoplasms proximate to an orthopaedic implant. Although the results of epidemiologic studies have not shown an excessive number of tumors in patients receiving stainless steel or superalloy implants, the possibility of carcinogenesis, given the corrosive environment in which metal implants exist, has prompted ongoing laboratory studies. Leaching of metal ions from implants, the synovial processing of metallic wear debris, and the effects of exposure to intraarticular metal particles have been the subjects of numerous laboratory studies. The results of these studies are summarized and recommended parameters for future laboratory investigations are given.

Oerskovia spp. are gram-positive, Nocardia-like bacilli which inhabit the soil and rarely cause human infections. Previously reported cases of Oerskovia infection have been characterized by a nonaggressive course and an association with foreign bodies. We report the first case of a patient with a prosthetic joint infection due to Oerskovia xanthineolytica. Our patient presented with a prolonged, indolent course and was thought to have aseptic loosening of his prosthesis until the time of surgery. He was cured of his infection by removal of the prosthesis, antibiotic therapy, and delayed reimplantation. Review of the previous 10 reported cases of Oerskovia infection in humans supports the recommendation that foreign-body-associated infections should be treated with a strategy that includes removal of the foreign material.

In a retrospective analysis, we evaluated the safety and efficacy of peripheral nerve blocks (PNB) compared to epidural anesthesia in 221 consecutive patients undergoing same-day bilateral total knee arthroplasty (TKA). Primary outcome measures included: hypotension requiring physician intervention, number of blood transfusions, perioperative hespan and crystalloid consumption, incidences of respiratory desaturation, pruritis, urinary retention, and nausea/vomiting. The incidences of hypotension, urinary retention, and pruritis were all higher in the epidural group, compared to PNB. Epidural patients also required more blood transfusions and greater volumes of hespan and crystalloid. PNB are safe and efficacious modality of analgesia for same day bilateral TKA and provide adequate pain relief with a significant decrease in postoperative complications compared to epidural anesthesia.

This article assesses the discriminant validity of a questionnaire designed to test patients' knowledge about total joint arthroplasty prior to preoperative educational intervention. The method employed was to compare responses on the test by surgeons, health care workers, and patients and to evaluate whether the test could discriminate among groups. A total of 148 patients, 59 health care workers and 28 orthopedic surgeons completed the questionnaire. The results show that patients are knowledgeable about the benefits of surgery, but are in need of information about surgical risks and complications. The test was able to discriminate between surgeons and the other two groups, but there were few differences between health care workers and patients. Item analysis also demonstrates that the test is reliable. Although the test exhibits acceptable psychometric properties, a major problem in using this test in evaluating educational interventions is the relatively high average score and the potential ceiling effect that prevents measurement of further gains in knowledge. More work is needed on expanding the test to include more items where knowledge of total joint arthroplasty is limited.

Cobalt (Co) was analyzed in sera obtained before surgery and in biopsies of periarticular soft tissue from 7 control patients undergoing primary total hip arthroplasty and from 6 Co-exposed patients who developed aseptic loosening of the femoral component after hip arthroplasty (CoCrMo alloy, greater than 59 percent Co, metal-on-plastic type). Serum-Co concentrations were not elevated in the Co-exposed patients compared with control patients or healthy adults. In 5 of the 6 Co-exposed patients, Co concentrations were greatly increased in periprosthetic tissue sections 0-1 mm from the synovial surface (median 2.4 [2.1-27] micrograms Co/g) compared with corresponding sections from the control patients (median 0.4 [0.1-0.6] microgram Co/g). Co concentrations diminished in tissue sections at successive distances of 2-3 and 4-5 mm from the synovial surfaces. In the Co-exposed patients, Co concentrations in sera and periprosthetic soft tissues were not correlated, indicating that serum Co concentration is not a reliable index of the Co burden in periprosthetic soft tissue.

AAOS Guideline on Preventing Venous Thromboembolic Disease in Patients Undergoing Elective Hip and Knee Arthroplasty Summary of Recommendations The following is a summary of the recommendations of the AAOS’ clinical practice guideline, Preventing Venous Thromboembolic Disease in Patients Undergoing Elective Hip and Knee Arthroplasty. This summary does not contain rationales that explain how and why these recommendations were developed, nor does it contain the evidence supporting these recommendations. All readers of this summary are strongly urged to consult the full guideline and evidence report for this information. We are confident that those who read the full guideline and evidence report will see that the recommendations were developed using systematic evidence-based processes designed to combat bias, enhance transparency, and promote reproducibility. This summary of recommendations is not intended to stand alone. Treatment decisions should be made in light of all circumstances presented by the patient. Treatments and procedures applicable to the individual patient rely on mutual communication between patient, physician, and other healthcare practitioners. We recommend against routine post-operative duplex ultrasonography screening of patients who undergo elective hip or knee arthroplasty. (Grade of Recommendation: Strong) Patients undergoing elective hip or knee arthroplasty are already at high risk for venous thromboembolism. The practitioner might further assess the risk of venous thromboembolism by determining whether these patients had a previous venous thromboembolism. (Grade of Recommendation: Weak) Current evidence is not clear about whether factors other than a history of previous venous thromboembolism increase the risk of venous thromboembolism in patients undergoing elective hip or knee arthroplasty and, therefore, we cannot recommend for or against routinely assessing these patients for these factors. (Grade of Recommendation: Inconclusive) Patients undergoing elective hip or knee arthroplasty are at risk for bleeding and bleeding-associated complications. In the absence of reliable evidence, it is the opinion of this work group that patients be assessed for known bleeding disorders like hemophilia and for the presence of active liver disease which further increase the risk for bleeding and bleeding-associated complications. (Grade of Recommendation: Consensus) Current evidence is not clear about whether factors other than the presence of a known bleeding disorder or active liver disease increase the chance of bleeding in these patients and, therefore, we are unable to recommend for or against using them to assess a patient's risk of bleeding. (Grade of Recommendation: Inconclusive) We suggest that patients discontinue antiplatelet agents (e.g., aspirin, clopidogrel) before undergoing elective hip or knee arthroplasty. (Grade of Recommendation: Moderate) We suggest the use of pharmacologic agents and/or mechanical compressive devices for the prevention of venous thromboembolism in patients undergoing elective hip or knee arthroplasty, and who are not at elevated risk beyond that of the surgery itself for venous thromboembolism or bleeding. (Grade of Recommendation: Moderate) Current evidence is unclear about which prophylactic strategy (or strategies) is/are optimal or suboptimal. Therefore, we are unable to recommend for or against specific prophylactics in these patients. (Grade of Recommendation: Inconclusive) In the absence of reliable evidence about how long to employ these prophylactic strategies, it is the opinion of this work group that patients and physicians discuss the duration of prophylaxis. (Grade of Recommendation: Consensus) In the absence of reliable evidence, it is the opinion of this work group that patients undergoing elective hip or knee arthroplasty, and who have also had a previous venous thromboembolism, receive pharmacologic prophylaxis and mechanical compressive devices. (Grade of Recommendation: Consensus) In the absence of reliable evidence, it is the opinion of this work group that patients undergoing elective hip or knee arthroplasty, and who also have a known bleeding disorder (e.g., hemophilia) and/or active liver disease, use mechanical compressive devices for preventing venous thromboembolism. (Grade of Recommendation: Consensus) In the absence of reliable evidence, it is the opinion of this work group that patients undergo early mobilization following elective hip and knee arthroplasty. Early mobilization is of low cost, minimal risk to the patient, and consistent with current practice. (Grade of Recommendation: Consensus) We suggest the use of neuraxial (such as intrathecal, epidural, and spinal) anesthesia for patients undergoing elective hip or knee arthroplasty to help limit blood loss, even though evidence suggests that neuraxial anesthesia does not affect the occurrence of venous thromboembolic disease. (Grade of Recommendation: Moderate) Current evidence does not provide clear guidance about whether inferior vena cava (IVC) filters prevent pulmonary embolism in patients undergoing elective hip and knee arthroplasty who also have a contraindication to chemoprophylaxis and/or known residual venous thromboembolic disease. Therefore, we are unable to recommend for or against the use of such filters. (Grade of Recommendation: Inconclusive)

There should be a low threshold to perform a systematic evaluation of patients with MoM hip arthroplasty as early recognition and diagnosis will facilitate the initiation of appropriate treatment prior to significant adverse biological reactions. A painful MoM hip arthroplasty has various intrinsic and extrinsic causes, and a systematic treatment approach based on the currently available data is presented to optimize management of MoM patients. The risk stratification algorithm presented will continue to develop as further evidence becomes available providing additional insights. While specialized tests such as metal ion analysis are useful modalities for assessing MoM hip arthroplasty, over-reliance on any single investigative tool in the clinical decision-making process should be avoided. Future research focusing on validation of the current diagnostic tools for detecting adverse local tissue reactions as well as optimization of MoM bearings and modular connections to further diminish wear and corrosion is warranted.

More than 200,000 people in the United States annually undergo knee replacement as a means of diminishing pain and stiffness and restoring mobility, and the number is expected to increase with further advancements in joint replacement procedures [Duke, 1999]. Total knee replacement is performed on people with severe degenerative joint disorder such as osteoarthritis in which the articular surfaces of the knee deteriorate, leading to severe pain, limitation or loss of function and/or deformity of the joint.

To establish the ability of a salvage procedure to restore an independent lifestyle, the SF-36 functional outcome instrument and the pain, mobility, and physical activity subscales of the Arthritis Impact Measurement Scale (AIMS) was used to assess patient function. Nine patients (10 knees) who had undergone arthrodesis for failed total knee arthroplasty were compared with a control group of successful primary total knee arthroplasty patients. Average clinical follow-up was 42 months (minimum: 24 months). For six of the eight SF-36 categories, the average scores for the arthrodesis and arthroplasty groups were similar. The average global scores for the two groups were nearly identical. The arthroplasty patients scored better on the AIMS physical activity and mobility subscales than the arthrodesis group, although the latter group fared better on the pain subscale. Overall, global scores favored the arthroplasty patients. The only subscales to show a statistically significant difference between the arthrodesis and arthroplasty groups were the SF-36 physical functioning and the AIMS physical activity subscales. This pilot study demonstrated the ability of a salvage procedure to allow for an independent lifestyle with minimal complications. Furthermore, despite its popularity, the SF-36 does not appear as sensitive as the AIMS to differences in functional status or health outcomes between total knee arthroplasty and arthrodesis patients.

A survey was conducted of the entire membership of the American Association of Hip and Knee Surgeons to determine their experience with total hip arthroplasty (THA) device-related failures. Forty-seven percent of the membership reviewed their preceding 5-year clinical experience and returned the survey instrument. The aggregate 5-year volume encompassed experience with more than 60,000 hip arthroplasties. The median 5-year experience per respondent was 200 metal-based sockets and 214 metal stems. The frequency distribution of the number of hip arthroplasties per respondent was skewed to the right, with fewer surgeons reporting the higher volumes of arthroplasties. In aggregate, 60,115 of the acetabular components used were metal backed. Nonmetal acetabular component usage totaled 3,219. Complete polyethylene failure was defined as fracture or complete wear through of the polyethylene portion of the component. Complete polyethylene failure was seen in 172 metal-backed sockets (29/10,000). Seventy-seven all-polyethylene sockets had complete polyethylene failure (239/10,100). A total of 87 THAs were revised for modular acetabular dissociations for a dissociation rate of 15/10,000. In aggregate, 64,483 metal-stemmed components were used. Femoral stem fractures occurred in 172 for a rate of 27/10,000. A total of 56,965 metallic femoral components were reported as being modular. Dissociation between the femoral head and neck was uncommonly seen (3/10,000). Use of ceramic femoral heads was low (5,023); however, a total of 11 ceramic head fractures were revised in the 5-year period for a failure rate of 22/10,000. The risks of catastrophic prosthetic THA failure are low but vary according to hip component and the manufacturer of the part.

Wear-debris powders of cobalt-chromium-molybdenum (CoCrMo) and titanium-aluminum-vanadium (TiAlV) alloys, which are widely used for orthopedic implants (eg, hip and knee prostheses), were tested for carcinogenic activity following intraarticular administration (20 mg/rat) to groups of 44 male Fischer-344 rats (Charles River Breeding Laboratories, North Wilmington, MA). Control groups received similar intraarticular injections of either a noncarcinogen (manganese powder, negative control rats) or a potent carcinogen (nickel subsulfide powder, positive control rats). The experimental groups of 8-12 rats were observed for 24 months after injection. No local tumors developed at the injection site in the negative control rats or in rats that received the CoCrMo or TiAlV powders; poorly differentiated or pleomorphic sarcomas developed at the injection site in 10 of the 12 positive control rats that were treated with nickel subsulfide. Incidences of primary tumors distant from the injection site did not differ significantly among the experimental groups. This study shows that, under experimental conditions, any carcinogenic activity of CoCrMo or TiAlV wear-debris powders is weak in comparison to nickel subsulfide. Based on this study and observations in other laboratories, intraarticular administration of test materials to rats provides a practical, reliable, and biologically relevant method for carcinogenesis testing of biomaterials used for orthopedic implants.

The biologic compatibility of ceramic materials has been widely demonstrated, and alumina (Al 2 O 3 ) has been used extensively in clinical applications for nearly 20 years. The authors examined the behavior of bone tissue adjacent to the alumina coating in eight cementless hip prosthetic stems that appeared radiologically stable and were explanted because of pain. Histologic evaluation demonstrated the presence of a consistent layer of decalcified bone tissue in continuity with and parallel to the prosthetic interface. Based on laboratory findings, the authors attribute this demineralization phenomenon to a high local concentration of aluminum ions with metabolic bone disease, which is histologically comparable to the osteomalacic osteo-dystrophy described in dialysis patients. These findings must be carefully considered given the potential long-term implications for alumina-coated implants.

In a prospective randomized study, 128 patients older than 55 years of age with a non-pathologic displaced femoral neck were followed for one-year. Evaluations were completed at 30 days, 60 days and one-year. The participants were 76.6% women, 93% Caucasian, had an average age of 82.3 years (range 55-100, std. dev. 8.4) and an average BMI of 23.8 (15.9 – 37.6, 4.2). At admission, 78% of patients lived at home.