The efficacy of Denosumab in the treatment of femoral head osteonecrosis: a retrospective comparative study.

The present study aimed to compare clinical and radiological differences of ONFH patients who were treated with denosumab, and a control group. A total of 178 patients (272 hips) with symptomatic, nontraumatic ONFH were divided into a denosumab group (98 patients, 146 hips) and a control group (80 patients, 126 hips). Patients in the denosumab group received a 60 mg subcutaneous dose of denosumab every 6 months. For the clinical assessments, Harris hip scores (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated. Plain radiographs and MRI were performed before and a minimum of 1 year after administration of denosumab, which were evaluated for radiological results including femoral head collapse (≥ 2 mm) and volume change of necrotic lesion. Femoral head collapse occurred in 36 hips (24.7%) in the denosumab group, and 48 hips (38.1%) in the control group, which was statistically significant (P = 0.012). Twenty-three hips (15.8%) in the denosumab group and 29 hips (23%) in the control group required THA, which showed no significant difference (P = 0.086). At the final follow-up, 71.9% of hips in the denosumab group had a good or excellent HHS compared with 48.9% in the control group, showing a significant difference (P = 0.012). The denosumab group showed a significantly higher rate of necrotic lesion volume reductions compared with the control group (P < 0.001). Denosumab can significantly reduce the volume of necrotic lesions and prevent femoral head collapse in patients with ARCO stage I or II ONFH.

Factors Affecting the Clinical Course of Subchondral Fatigue Fracture of the Femoral Head.

Background: Subchondral fatigue fracture of the femoral head (SFFFH) is a rare disease, and its disease entity is established in recent decades. Although there are a few studies on SFFFH, most of them are case series involving around 10 cases, and the clinical course of SFFFH is still not well known. This study analyzed the factors affecting the clinical course of SFFFH. Methods: Patients who visited our institution from October 2000 to January 2019 were retrospectively evaluated. Of eligible cases, 89 hips (80 patients) were diagnosed with SFFFH and non-surgical treatment outcomes were analyzed. Radiographs and medical charts were reviewed for following factors: the degree of femoral head collapse, the interval between the onset of hip pain and the first hospital visit, hip dysplasia, osteoarthritic changes, sex, and age. Results: Hip pain decreased in 82 cases (92.1%) through non-surgical treatment, and 7 cases (7.9%) underwent surgery. Patients with good results of non-surgical treatment had improvement 2.9 months on average after the treatment. All cases without a collapsed femoral head (55 cases) had hip pain alleviation through non-surgical treatment. Cases with femoral head collapse of 4 mm or less and non-surgical treatment within 6 months from the onset of hip pain (22 cases) all had hip pain alleviation. Among 8 cases with femoral head collapse of 4 mm or less and non-surgical treatment after 6 months or more from the onset of hip pain, 3 underwent surgery and 1 had persistent hip pain. Those with femoral head collapse of over 4 mm (3 cases) all underwent surgery. The osteoarthritic changes, dysplastic hip, sex, and age were not statistically related to the success of non-surgical treatment. Conclusions: The success of non-surgical treatment for SFFFH can be affected by the degree of femoral head collapse and the timing of non-surgical treatment.

Forte ceramic-on-delta ceramic cementless total hip arthroplasty: an 8- to 15-year follow-up study.

INTRODUCTION: Forte ceramic head on delta ceramic liner articulation showed satisfactory midterm results without ceramic-related complication. We aimed to investigate the clinical and radiological outcomes of cementless total hip arthroplasty (THA) with forte ceramic head on delta ceramic liner articulation. MATERIALS AND METHODS: Overall, 107 patients (57 men, 50 women; 138 hips) who underwent cementless THA with forte ceramic head on delta ceramic liner articulation were enrolled. The mean follow-up duration was 11.6 years. For the clinical assessments, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), presence of thigh pain, and presence of squeaking were evaluated. Radiographs were assessed to search for osteolysis, stem subsidence, loosening of implants. Kaplan-Meier survival curves were evaluated. RESULTS: The mean HHS and WOMAC improved from 57.1 and 28.1 preoperatively to 81.4 and 13.1 at the final follow-up, respectively. Nine revisions (6.5%) were performed; 5 hips for stem loosening, 1 hip for ceramic liner fracture, 2 hips for periprosthetic fracture, and 1 hip for progressive osteolysis around cup and stem. Thirty-two patients (37 hips) complained squeaking, in which 4 cases (2.9%) were identified as ceramic-related noises. After a mean follow-up period of 11.6 years, 91% (95% CI 87.8-94.2) were free from revision of both femoral and acetabular components due to any reason. CONCLUSIONS: Cementless THA with forte ceramic-on-delta ceramic articulation showed acceptable clinical and radiological results. Serial surveillance of these patients should be performed due to the possibility of cerami- related complications such as squeaking, osteolysis, and ceramic liner fracture.

Incomplete Intertrochanteric Fracture: A Pattern Analysis Using Multiplanar Reformation Computed Tomography.

Background: Incomplete fractures are assumed to occur in the intertrochanteric area as fractures at other sites, but reports of incomplete intertrochanteric fractures (IIFs) are rare. In 1999, Schultz et al. defined isolated greater trochanter fractures (GTFs) as IIFs when intertrochanteric extension is observed on magnetic resonance (MR) images. On multiplanar reformation computed tomography (MPR CT) images acquired for further study of apparently isolated GTFs, we noted incomplete cortical breakage in the intertrochanteric area. We then found that the fracture line was incomplete on plain radiographs in some intertrochanteric fractures. We evaluated IIFs and apparently isolated GTFs using MPR CT and analyzed the fracture patterns of IIFs that were confirmed using MPR CT. Methods: Between February 2006 and June 2019, 36 cases of IIF were detected using MPR CT in 36 patients. They were 17 women and 19 men with a mean age of 74.7 years (range, 26-94 years). Plain radiographs and MPR CT images were evaluated by two experienced orthopedic surgeons. In addition, MR imaging was performed in 5 cases. Results: Plain radiographs showed no evidence of fracture in 2 cases, isolated GTF in 7 cases, and IIF in 27 cases. In all cases, incomplete cortical breakage in the intertrochanteric area was confirmed on MPR CT images. Cortical breakage was located in the anterior portion of the intertrochanteric area, whereas the posterior portion remained intact in all cases. The detection rate of cortical breakage was higher on coronal or sagittal images than that on axial images. On MR images of 5 cases, intertrochanteric extensions were found in the medullary space. All extensions originated in the greater trochanter area and extended anteriorly in the axial plane and inferomedially in the coronal plane. On the T1-weighted mid-coronal image, the extension reached or passed the midline in 3 cases, and cortical breakage was detected in only 2 cases. Conclusions: In all cases of IIF, cortical breakage was detected in the anterior portion of the proximal femur, leaving the posterior cortex intact. This finding is notably different from that of intertrochanteric extension (from posterior to anterior) detected on MR images of isolated GTFs.

A Comparative Study of Hesperetin, Hesperidin and Hesperidin Glucoside: Antioxidant, Anti-Inflammatory, and Antibacterial Activities In Vitro.

The antioxidant, anti-inflammatory and antibacterial activities of hesperetin, hesperidin and hesperidin glucoside with different solubility were compared in vitro. Hesperetin was prepared by enzymatic hydrolysis from hesperidin, and hesperidin glucoside composed of hesperidin mono-glucoside was prepared from hesperidin through enzymatic transglycosylation. Solubility of the compounds was different: the partition coefficient (log P) was 2.85 ± 0.02 for hesperetin, 2.01 ± 0.02 for hesperidin, and -3.04 ± 0.03 for hesperidin glucoside. Hesperetin showed a higher effect than hesperidin and hesperidin glucoside on radical scavenging activity in antioxidant assays, while hesperidin and hesperidin glucoside showed similar activity. Cytotoxicity was low in the order of hesperidin glucoside, hesperidin, and hesperetin in murine macrophage RAW264.7 cells. Treatment of the cells with each compound reduced the levels of inflammatory mediators, nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). Hesperetin was most effective at relatively low concentrations, however, hesperidin glucoside was also effective at higher concentration. Hesperetin showed higher antibacterial activity than hesperidin in both Gram-positive and -negative bacteria, and hesperidin glucoside showed similarly higher activity with hesperetin depending on the bacterial strain. In conclusion, hesperetin in the form of aglycone showed more potent biological activity than hesperidin and hesperidin glucoside. However, hesperidin glucoside, the highly soluble form, has been shown to increase the activity compared to poorly soluble hesperidin.

The risk factors for subsequent fractures after distal radius fracture.

INTRODUCTION: The purpose of this study was to evaluate the risk factors for subsequent fractures after distal radius fracture (DRF). MATERIALS AND METHODS: We retrospectively reviewed 705 patients with DRF who performed dual-energy X-ray absorptiometry within six months before or after the DRF and followed more than 12 months. We identified patients with subsequent fractures and multivariate logistic regression analyses were conducted with demographic information, underlying disease status, and bone fragility parameters at the time of DRF to evaluate the risk factors for subsequent fractures. RESULTS: Subsequent fractures occurred in 56 patients (7.9% of 705 patients) with 65 fractures at a mean time of 33.5 months after DRF. In multivariate logistic regression analysis, older age (OR 1.032; 95% CI, 1.001-1.064, p = 0.044), diabetes mellitus (DM) (OR 2.663; 95% CI, 1.429-4.963, p = 0.002) and previous fracture history (OR 1.917; 95% CI, 1.019-3.607, p = 0.043), and low total hip BMD (OR 1.410; 95% CI, 1.083-1.836, p = 0.011) were significant risk factors for the occurrence of subsequent fractures. CONCLUSION: This study demonstrated that older age, DM, previous fracture history and low hip BMD are the risk factors for subsequent fractures after DRF. Active glycemic control would have a role in patients with DM and a more aggressive treat-to-target approach may be necessary for patients with low BMDs to prevent subsequent fractures after DRF.

Further Imaging for Suspected Isolated Greater Trochanteric Fractures: Multiplanar Reformation Computed Tomography or Magnetic Resonance Imaging.

BACKGROUND: Most isolated greater trochanter (IGT) fractures are treated conservatively. However, some require surgical fixation although indications for surgery have not yet been established. Many surgeons perform surgical fixation when the intertrochanteric extension crosses the midline on magnetic resonance (MR) images. Nevertheless, for mechanical strength, cortical bone integrity is more important than that of intramedullary cancellous trabeculae. We retrospectively evaluated the clinical usefulness of multiplanar reformation computed tomography (MPR CT) in determining treatment strategies for IGT fractures. METHODS: We evaluated 99 cases of suspected IGT fractures between October 2004 and December 2019. They were 66 women and 33 men with a mean age of 77 years. The mean follow-up period was 34 months. Most patients were evaluated with plain radiographs, followed by additional imaging study via MPR CT in 65 cases, magnetic resonance imaging (MRI) in 5 cases, and both in 17 cases. Typically, fractures were fixed surgically when a cortical breakage was detected in the intertrochanteric area on MPR CT, while fractures without evidence of cortical breakage on MPR CT were treated conservatively. RESULTS: In 13 out of 82 cases evaluated by MPR CT, incomplete cortical breakage in the intertrochanteric area was detected, of which 10 were treated surgically. The remaining 3 cases were treated conservatively due to patient's refusal, poor medical condition, and failure to detect breakage. Of 69 cases without cortical breakage, 61 cases were successfully treated conservatively. Among the 17 cases evaluated by both MPR CT and MRI, cortical breakage was detected in 3, of which the intertrochanteric extension crossed the midline on the MR image only in 1 case. Of the remaining 14 cases without breakage, the intertrochanteric extension crossed the midline in 5. Among these 5 cases, 3 were treated conservatively. CONCLUSIONS: The results suggest that MPR CT is a useful imaging modality for further evaluation of IGT fractures. It was especially valuable in evaluating cortical bone integrity, which may be more critical for fracture stability.

A comparison of barbed continuous suture versus conventional interrupted suture for fascial closure in total hip arthroplasty.

A barbed suture is a self-anchoring knotless suture hypothesized to shorten suture time and reduce the tension point of the wound. The purpose of this study was to compare the barbed suture and the interrupted suture for fascial closure in total hip arthroplasty. We retrospectively reviewed patients who underwent total hip arthroplasty from March 2014 to June 2020. We evaluated 324 cases among 274 patients consisting of 188 males and 86 females. We collected the following data: demographics, time for wound closure, the number of threads used, hemoglobin level, surgical site pain, and wound complications. Variables were analyzed for their association with closure time using multiple regression analyses between the barbed suture (the SFX group) and the interrupted suture (the Vicryl group). Mean closure time was 5.8 min lower and the mean number of sutures used was 2.2 lower in the SFX group versus the Vicryl group (P < 0.01 and < 0.01, respectively). There were no statistical intergroup differences in the mean largest hemoglobin drop, the incidence of transfusion, surgical site pain, and the incidence of wound complications. The use of barbed sutures for fascial closure in total hip arthroplasty effectively reduces the surgical time without increasing wound complications.

Ultrasound-Guided Anterior Quadratus Lumborum Block Reduces Postoperative Opioid Consumption and Related Side Effects in Patients Undergoing Total Hip Replacement Arthroplasty: A Propensity Score-Matched Cohort Study.

Quadratus lumborum block (QLB) has been shown to be effective for pain relief after hip surgery. This study evaluated the efficacy of ultrasound-guided anterior QLB in pain control after total replacement hip arthroplasty (TRHA). A total of 115 patients receiving anterior QLB were propensity score-matched with 115 patients who did not receive the block. The primary outcome was opioid consumption at 24, 24-48, and 48 postoperative hours. Secondary outcomes included pain scores at the post-anesthesia care unit (PACU), 8, 16, 24, 32, 40, and 48 h length of hospital stay, time to first ambulation, and the incidence of opioid-related side effects. Postoperative opioid consumption 48 h after surgery was significantly lower in the QLB group. Resting, mean, worst, and the difference of resting pain scores compared with preoperative values were significantly lower in the QLB group during the 48 postoperative hours. The length of hospital stay was shorter in the QLB group. The incidence of postoperative nausea and vomiting was significantly lower in the QLB group during the 48 postoperative hours, except at the PACU. This study suggests that anterior QLB provides effective postoperative analgesia for patients undergoing THRA performed using the posterolateral approach.

Impingement Between the Metal Stem and the Ceramic Liner in Total Hip Arthroplasty: The Neck Is Not the Only Place Where Impingement Occurs.

BACKGROUND: It is assumed that impingement between the ceramic liner and the stem increases the possibility of a liner fracture in total hip arthroplasty with a ceramic-on-ceramic bearing. The purpose of this study was to analyze the pattern of the impingement by evaluating the notches (U-shaped indented wear scars engraved on the stem) on radiographs to determine when and where impingement develops and to analyze the factors affecting its occurrence. METHODS: Among the primary total hip arthroplasty cases using a ceramic-on-ceramic bearing performed from November 1997 to December 2003, 244 cases of 197 patients (123 male patients and 74 female patients) that had follow-up of ≥15 years were included. All of the radiographs were examined with special regard to the notches and the cup positions. RESULTS: Notches were detected at 77 sites of 57 cases (23.4%) for the first time between 8 months and 14.8 years after the surgical procedure. They were located on the neck or the shoulder of the stem. Shoulder notches were detected only in the cases with a short-neck head. Shoulder notches were found in 29 cases (20.0% of short-neck cases). Cup inclination was lower (p = 0.01) and anteversion was higher (p = 0.01) in the group with notches than the group without notches. There were 5 cases of ceramic head fracture. One of them experienced another ceramic liner fracture, assumed to be caused by prosthetic shoulder impingement, after the revision surgical procedure. CONCLUSIONS: The results of this study suggest that impingement between the stem and the ceramic liner occurs in a considerable proportion of patients who underwent total hip arthroplasty not only on the neck but also on the shoulder of the stem. Forceful and abrupt impingement on the stem shoulder can cause ceramic liner fracture. Impingement between the stem shoulder and the ceramic liner should be considered in designing a stem. It seems to be prudent to recommend that patients avoid squatting or sitting cross-legged on the floor as much as possible. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopy versus nonoperative treatment of symptomatic femoroacetabular impingement syndrome: A systematic review and meta-analysis.

BACKGROUND: Presently, hip arthroscopy is a widely adopted surgical intervention for the treatment of femoroacetabular impingement (FAI). However, there is insufficient evidence regarding which between arthroscopy and nonoperative treatment is more optimal for symptomatic FAI. METHODS: MEDLINE, Embase, Web of Science, and the Cochrane Library were systematically searched for studies that compared arthroscopy and nonoperative interventions for FAI treatment from inception to August 4, 2020. We included studies that directly compared surgical and nonsurgical treatment for symptomatic FAI and excluded those that did not use arthroscopic treatment as a surgical technique and studies performed on patients with concomitant diagnoses instead of pure FAI. We compared the following clinical outcome scores at 6 and 12 months of follow-up: International Hip Outcome Tool 33 (iHOT-33), hip outcome score (HOS), EuroQol-visual analog scale (EQ-VAS), modified Harris hip score (mHHS), and nonarthritic hip score (NAHS). RESULTS: Five studies totaling 838 patients were included in the qualitative and quantitative synthesis; 382 patients underwent hip arthroscopy, and 456 patients were treated by nonoperative interventions. At 6 months of follow-up, there were no statistically significant differences in iHOT-33 ratings (mean difference [MD] = 7.92, P = .15), HOS (MD of HOS-ADL = 5.15, P = .26 and MD of HOS-Sports = 2.65, P = .79, respectively), and EQ-VAS (MD = 1.22, P = .76) between the 2 treatment strategies. At 12 months of follow-up, the arthroscopy group had a greater mean improvement in iHOT-33 score than the conservative treatment group (MD = 8.42, P = .002), but there was no difference between the groups in terms of mHHS rating (MD = -0.24, P = .83) and NAHS (MD = -2.08, P = .09). CONCLUSION: Despite arthroscopy being associated with significantly superior iHOT-33 scores after 12 months of follow-up, we were unable to discern the difference between the treatment strategies using other scoring methods, such as HOS, EQ-VAS, mHHS, and NAHS. Further studies will be needed to conclusively determine if 1 strategy is superior to the other for treating FAI.

A novel arthroscopic classification of labral tear in hip dysplasia.

BACKGROUND: Acetabular labral tears cause of pain in patients with symptomatic hip dysplasia. To date, no structured grading system has been developed to evaluate labral tears in these patients. The present study describes a new system of grading labral tears in patients with acetabular dysplasia. METHODS: The data of 66 patients who underwent hip arthroscopy for symptomatic hip dysplasia from March 2014 to February 2018 were reviewed. Labral tears were classified into four groups, based on the occurrence of chondrolabral junction (CLJ) disruption, capsulolabral recess (CLR) disruption, and labral displacement. Labral tears without instability were classified as grade 1 or 2. Partial delamination or blistering of the labrum with minimal fraying at the CLJ was classified as grade 1, whereas labral tears with CLJ disruption were classified as grade 2. Unstable labral tears with CLR disruption followed by CLJ disruption, but without labral displacement, were classified as grade 3, whereas unstable labral tears with CLR and CLJ disruption, but with labral displacement, were classified as grade 4. The radiological and clinical characteristics of patients in each grade were determined including by simple radiographs and MRI/MR arthrography, as were concomitant findings, including rupture of the ligamentum teres, articular cartilage damage, and presence of a paralabral cyst. The surgical options selected for each grade and clinical outcomes, including modified Harris hip scores (mHHS) and Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) scores, were evaluated. Spearman's correlation analyses were performed to assess whether labral tear grade correlated with baseline characteristics, the incidence of concomitant injuries, and the severity of osteoarthritis (OA). The Wilcoxon test for paired data was performed to compare treatment results with pain scores. RESULTS: The study cohort included six men and 53 women of mean ± SD age 39.9 ± 13.0 years (range, 15-66 years). Of the 66 hips, seven (10.6%), 10 (15.2%), 30 (45.5%), and 19 (28.8%) were classified as grades 1-4, respectively. Symptom duration (P = 0.017), preoperative Tönnis OA grade (P < 0.001), cartilage damage (P < 0.001), and the presence of a paralabral cyst (P = 0.001) correlated significantly with baseline tear grade. In all groups, mHHS and WOMAC scores improved after surgical treatment. CONCLUSIONS: Arthroscopic findings of labral tears in patients with hip dysplasia differed from the conventional classification. The classification system proposed in this study will likely be useful for determining the degree of labral tear in patients with hip dysplasia and for predicting treatment outcomes.

Ceramic Liner Fracture Caused by an Impingement between the Stem Shoulder and the Ceramic Liner.

Mechanisms of ceramic liner fractures have not yet been fully elucidated. Impingement between a stem and ceramic liner is a proposed cause of ceramic liner fractures. We experienced a case of ceramic liner fracture caused by direct impingement between the stem shoulder and the ceramic liner. This type of impingement, unlike impingements with a stem neck, has not been previously reported. While we assume that certain characteristics of the stem contributed to the impingement, we report this case to note that caution may be needed when using certain stem designs.

Hip Arthroscopy for Femoroacetabular Impingement and Concomitant Labral Tears: A Minimum 2-Year Follow-Up Study.

PURPOSE: The present study investigated the minimum 2-year outcomes of hip arthroscopy for femoroacetabular impingement (FAI) and concomitant labral tears in Asian patients. METHODS: Patients who underwent hip arthroscopy for both FAI and concomitant labral tears between January 2012 and December 2017 were included. Patients with hip osteoarthritis of Tönnis grade ≥2, previous hip surgery, or followed for less than 2 years were excluded. Clinical assessments were performed using the modified Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, and the rates of achieving threshold values of the minimal clinically important difference and patient acceptable symptomatic state at the latest follow-up. Plain radiographs were acquired pre- and postoperatively for radiologic assessments. RESULTS: A total of 73 patients (90 hips, 58 male, 15 female; mean age 34.4 years) who underwent hip arthroscopy for FAI and concomitant labral tears were enrolled. Forty-three hips (47.8%) had cam-type, 7 (7.8%) had pincer-type, and 40 (44.4%) had mixed-type FAI. The mean follow-up duration was 5.2 years. In cam- and mixed-type FAI hips, the mean α angle significantly decreased from 66.7 ± 8.28° preoperatively to 44.9 ± 3.78° postoperatively (95% confidence interval [CI] 19.6°-22.8°; P < .001). The mean modified Harris Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index increased from 74.8 ± 13.2 and 75 ± 12.7 preoperatively to 93 ± 8.1 (95% CI 15.4-20.9; P = .001) and 89.4 ± 8.4 postoperatively (95% CI 11.8-17; P = .001), respectively. Seventy-four hips (82.2%) crossed the minimal clinically important difference, and 85 hips (94.4%) had achieved the patient acceptable symptomatic state. There were 2 cases of pudendal nerve palsy and 1 case of sciatic nerve palsy. No additional surgeries were required. CONCLUSIONS: Hip arthroscopy can be an effective treatment for FAI and concomitant labral tears in Asian patients as demonstrated in this study, with improved PRO scores and reoperation rates. Longer-term studies with larger cohorts are necessary. LEVEL OF EVIDENCE: Level IV, case series.

The Effect of Povidone-Iodine Lavage in Preventing Infection After Total Hip and Knee Arthroplasties: Systematic Review and Meta-Analysis.

BACKGROUND: Dilute povidone-iodine (PI) lavage, a simple disinfection method, could reduce postoperative infection risk. However, there is no clinical consensus regarding its efficacy in total joint arthroplasties (TJAs). This systematic review and meta-analysis evaluated PI lavage's efficacy in preventing infection after TJA. METHODS: MEDLINE, Embase, and the Cochrane Library were systematically searched for studies published before November 22, 2019, that compared postoperative infection rates in patients who underwent TJA with or without PI lavage before wound closure. Subgroup analyses were designed to identify the differences in infection site (overall or deep), type of surgery (total hip arthroplasty or total knee arthroplasty), time until diagnosis of infection (3 or 12 months postoperatively), and primary/aseptic revision arthroplasties. RESULTS: We included 7 studies with 31,213 TJA cases, comprising 8861 patients who received PI lavage and 22,352 who did not. Pooled odds ratio for overall infection rate for the PI and non-PI lavage groups was 0.67 (95% confidence interval, 0.38-1.19, P = .17) and for the deep infection rate was 0.90 (95% confidence interval, 0.27-2.98, P = .86). Subgroup analyses revealed no differences in postoperative infection rates between the PI and non-PI lavage groups in terms of total hip arthroplasty and total knee arthroplasty, diagnosis of infection at 3 and 12 months postoperatively, or primary and aseptic revision arthroplasties. CONCLUSION: We detected no differences in the overall postoperative infection rates between the PI and non-PI lavage groups before wound closure in TJA including all studies in the subgroup analyses.

Fabrication of Ni compound nanocrystal/nanocarbon composites by cooling of chloride-based fluxes.

Unique Ni compound nanocrystals were successfully grown on carbon nanotubes (CNTs) by cooling a mixed chloride flux. Cup-stacked CNTs (CSCNTs) were used as the nanocarbon materials because of their structural features. The grown nanocrystals had a nanosheet structure, which was densely assembled and had a ribbon-like morphology. Therefore, the nanocrystal/CSCNT composites were expected to have a highly active surface area for the catalyst composites. The selected area electron diffraction pattern and the related radial intensity profiles indicated that the grown nanocrystals were Ni(OH)2. When the pristine CSCNTs were used as a starting material, the formation efficiency of the nanocrystal/CSCNT composites decreased because the pristine CSCNTs were not dispersed in the KCl-LiCl flux. Therefore, functionalization of the CSCNTs was carried out with VUV light irradiation. The dispersibility of the VUV light-treated CSCNTs increased in the KCl-LiCl flux in comparison with the pristine CSCNTs because oxygen-containing functional groups, such as -COOH and -CO, were introduced onto the surfaces of the CSCNTs.

Fabrication of highly crystalline NbOx nanotube/cup-stacked CNT nanocomposites.

Carbon nanotubes (CNTs) are promising catalyst supports for fuel cell applications. Metal oxide/CNT nanocomposites are also being studied for dye-sensitized solar-cell, photocatalyst, and sensor applications. The fabrication of nanocomposites consisting of highly crystalline NbOx nanotubes and cup-stacked carbon nanotubes (CSCNTs) is reported herein. The CSCNTs were selected for the carbon materials because of their distinctive structure. The CSCNTs were photochemically treated with vacuum ultraviolet light, which increased the amount of oxygen-containing functional groups therein. NbOx nanotubes with no defects were successfully prepared with the chemical treatment of highly crystalline, layered, flux-grown K4Nb6O17 crystals. First, K4Nb6O17 crystals were grown from a KCl flux at a holding temperature of 800 degrees C. Next, NbOx nanosheets were prepared from the layered K4Nb6O17 crystals via a two-step exfoliation process, which consists of proton exchange in an acid solution and intercalation of the tetrabutylammonium ions. The NbOx nanosheets were rolled up into nanotubes with diameters of about 20 nm and lengths of 100-500 nm on the surfaces of the CSCNTs; thus, unique and complex NbOx/CSCNT nanocomposites were successfully fabricated.

Fabrication of highly ordered, macroporous Na2W4O13 arrays by spray pyrolysis using polystyrene colloidal crystals as templates.

Highly ordered, macropore arrays, that is, inverse opal structures, of Na2W4O13 were successfully synthesized by spray pyrolysis using polystyrene (PS) colloidal crystals as templates. A densely packed monolayer of monodisperse PS microspheres was deposited on a silica glass substrate by use of the Langmuir-Blodgett thin film technique. Subsequently, Na2W4O13 layers were deposited on the PS templates as a thin layer by spray pyrolysis of a 5(NH4)2O.12WO(3).5H2O-NaCl solution. The PS templates were, finally, removed by thermal treatment, generating a surface with features (inverse opal structures) located where the interstitial space of the densely hexagonal-packed PS microspheres had been. The macroporous structures obviously depended on the annealing conditions such as time and temperature. The macropores were basically hemispherical in shape and highly honeycombed arrangement, which corresponded well to the PS templates. The inverse opal textures of Na2W4O13 layer surfaces enhanced their hydrophobicity. The surfaces modified by fluoroalkylsilane (FAS) were converted from hydrophobic (water contact angle=127 degrees) to hydrophilic (30 degrees) by photocatalytic oxidation using the Na2W4O13 crystal layer. The Na2W4O13 crystals exhibited high activity for FAS photodegradation.

Comparative study of the molecular aggregation state of alkyl organic monolayers prepared on Si and hydrogen-terminated Si substrates.

A comparative study of the molecular aggregation states of n-octadecyltrichlorosilane (OTS) and octadecene monolayers was carried out based on water contact angle, x-ray reflectivity (XR), grazing incidence x-ray diffraction (GIXD), and Fourier transform infrared spectroscopy (FT-IR) measurements. Water contact angle, XR, and FT-IR measurements revealed that the packing density and orientational order of the OTS were higher than those of octadecene. The OTS monolayer was in a hexagonal crystalline state with (10) spacing of 0.417 nm, whereas the octadecene monolayer was in an amorphous state. The growth mechanisms of the OTS and octadecene monolayers are also proposed. The alkyl molecular aggregation states strongly depended on the chemical bonding state at the interface between the alkyl organic molecule and the substrate surface.