Latest Trends on the Attenuation of Systemic Foreign Body Response and Infectious Complications of Synthetic Hernia Meshes.

Throughout the past few years, hernia incidence has remained at a high level worldwide, with more than 20 million people requiring hernia surgery each year. Synthetic hernia meshes play an important role, providing a microenvironment that attracts and harbors host cells and acting as a permanent roadmap for intact abdominal wall reconstruction. Nevertheless, it is still inevitable to cause not-so-trivial complications, especially chronic pain and adhesion. In long-term studies, it was found that the complications are mainly caused by excessive fibrosis from the foreign body reaction (FBR) and infection resulting from bacterial colonization. For a thorough understanding of their complex mechanism and providing a richer background for mesh development, herein, we discuss different clinical mesh products and explore the interactions between their structure and complications. We further explored progress in reducing mesh complications to provide varied strategies that are informative and instructive for mesh modification in different research directions. We hope that this work will spur hernia mesh designers to step up their efforts to develop more practical and accessible meshes by improving the physical structure and chemical properties of meshes to combat the increasing risk of adhesions, infections, and inflammatory reactions. We conclude that further work is needed to solve this pressing problem, especially in the analysis and functionalization of mesh materials, provided of course that the initial performance of the mesh is guaranteed.

Adverse Local Tissue Reactions are Common in Asymptomatic Individuals After Hip Resurfacing Arthroplasty: Interim Report from a Prospective Longitudinal Study.

BACKGROUND: The evaluation of the natural history prevalence of adverse local tissue reactions (ALTRs) using MRI has focused only on metal-on-metal (MoM) bearing surfaces without comparison to nonMoM bearing surfaces. QUESTIONS/PURPOSES: To determine (1) the longitudinal changes and differences in blood metal ion levels in patients with hip resurfacing arthroplasty (HRA), ceramic-on-ceramic (CoC) THA, and metal-on-polyethylene (MoP) THA compared with those undergoing ceramic-on-polyethylene (CoP) THA; (2) how the longitudinal change of synovial reaction classification in patients with HRA, CoC THA, and MoP THA compares with those undergoing CoP THA, and whether there is an association between the presence of an ALTR or metallosis on MRI with corresponding patient-reported outcomes, or the presence of capsular dehiscence; and (3) differences in blood metal ion levels between patients undergoing HRA with an ALTR or metallosis on MRI and those with HRA without these conditions. METHODS: Between March 2014 and February 2019, 22,723 patients underwent primary HRA and THA at one center. Patients received an HRA based on their desired athletic level after surgery and the presence of normal acetabular and proximal femoral bone morphology without osteopenia or osteoporosis. Two percent (342 of 22,723) of patients were contacted to participate, and 71% (243 of 342 hips in 206 patients) were enrolled for analysis at baseline. The patients underwent arthroplasty for degenerative joint disease, and 25 patients withdrew over the course of the study. We included patients who were more than 1 year postarthroplasty. All participants had an MRI examination and blood serum ion testing and completed a Hip Disability and Osteoarthritis Outcome Score survey annually for four years (baseline, year 1, year 2, year 3). Morphologic and susceptibility-reduced MR images were evaluated by a single radiologist not involved in the care of patients for the presence and classification of synovitis (Gwet AC1: 0.65 to 0.97), synovial thickness, and volume (coefficient of repeatability: 1.8 cm3). Linear mixed-effects models were used to compare the mean synovial thickness, synovial volume, and Hip Disability and Osteoarthritis Outcome Score subscales between bearing surfaces at each timepoint and within each bearing surface over time. Marginal Cox proportional hazards models were used to compare the time to and the risk of developing ALTR only, metallosis only, and ALTR or metallosis between bearing surfaces. All models were adjusted for age, sex, BMI, and length of implantation based on known confounders for hip arthroplasty. Adjustment for multiple comparisons was performed using the Dunnett-Hsu method. RESULTS: Patients with unilateral HRA had higher cobalt and chromium serum ion levels (baseline: 1.8 ± 0.8 ppb, year 1: 2.0 ± 1.5 ppb, year 2: 2.1 ± 1.2 ppb, year 3: 1.6 ± 0.7 ppb) than those with unilateral CoP bearings (baseline: 0.0 ± 0.1 ppb, year 1: 0.1 ± 0.3 ppb, year 2: 0.0 ± 0.2 ppb, year 3: 0.0 ± 0.0 ppb) at all timepoints (p < 0.001 for each time point). More patients who received an HRA developed ALTR or metallosis on MRI than did patients with CoP bearings (hazard ratio 4.8 [95% confidence interval 1.2 to 18.4]; p = 0.02). There was no association between the longitudinal change of synovial reaction to ALTR or metallosis on MRI with patient-reported outcomes. In addition, there was no association between the presence of dehiscence at baseline and the subsequent development of ALTR or metallosis, as seen on MRI. There were elevated cobalt (4.7 ± 3.5 ppb) and chromium (4.7 ± 2.6 ppb) serum levels in patients with unilateral HRA who had an ALTR or metallosis present on MRI at year 1 compared with patients without an ALTR or metallosis on MRI (cobalt: 1.8 ± 1.0 ppb, mean difference 4.7 ppb [95% CI 3.3 to 6.0]; p < 0.001; chromium: 2.3 ± 0.5 ppb, mean difference 3.6 ppb [95% CI 2.2 to 5.0]; p < 0.001) as well as for chromium at year 3 (3.9 ± 2.4 ppb versus 2.2 ± 1.1 ppb, mean difference 1.3 ppb [95% CI 0.3 to 2.4]; p = 0.01). CONCLUSION: We found a higher proportion of ALTR or metallosis on MRI in patients with HRA compared with patients with CoP, even when patient self-assessed symptomatology of those with an ALTR or metallosis on MRI was not different than the absence of these features. MRI detected ALTRs in high-function patients, emphasizing that an annual clinical assessment dependent on survey or blood ion testing alone may not detect soft tissue complications. The results of this study are in line with prior consensus recommendations of using MRI as part of a routine follow-up protocol for this patient population. LEVEL OF EVIDENCE: Level III, therapeutic study.

Tissue Response to Subcutaneous Infusion Catheter.

Insulin infusion pump, continuous glucose monitoring (CGM), and insulin infusion set (IIS) have been developed to be increasingly feasible for people with type 1 diabetes (T1D). Several recently approved CGMs are transitioning from 7-day to 10-day wear time without the need for fingerprick recalibration. Nevertheless, studies and improvements on IIS, a critical part of insulin pump therapy, have been limited. In particular, the recommended wear time of IIS is still 2-3 days, which can hardly match the current duration of CGM for potential closed-loop system development. It is generally believed that both the inserted catheter and the subsequent infused insulin drug could induce particular subcutaneous tissue response and skin-related complications at the infusion site. In certain cases, poor glycaemic control, increased risk of hypoglycemia, and serious cosmetic impact on people with diabetes were observed. Skin complication has also been attributed as an important factor resulting users to discontinue insulin pump therapy. This article provides the rare systematic review of IIS induced subcutaneous tissue responses and skin complications, including the impacts from the inserted catheters, the subcutaneous infused insulin, and the adhesive or tape used to immobilize the catheter. The FDA's recommendation for the frequency of IIS change was further discussed. Future studies on this topic are required to further understand the IIS-related problems, and future strategies could be developed accordingly to significantly reduce the incidence of these problems, extend the wear time, and increase the acceptance of insulin pump based therapy.

Cutaneous Complications With Continuous or Flash Glucose Monitoring Use: Systematic Review of Trials and Observational Studies.

BACKGROUND: Continuous glucose monitoring (CGM)/flash glucose monitoring (FGM) use in diabetes management is increasing. Cutaneous complications associated with these devices were reported. We conducted a systematic review to provide an overview of cutaneous complications with CGM/FGM use. METHODS: We identified observational studies and intervention trials that report on cutaneous complications with CGM/FGM use up to January 14, 2019. Studies were identified through Medline, Embase, and PubMed, or with hand searching of the previous publications. Screening was duplicated and data extracted to consider four main themes: incidence rate and severity, participant perspectives of cutaneous complications, potential solutions, and future directions in diabetic technology relevant to reducing cutaneous complications. RESULTS: A total of 54 eligible studies were identified. The overall event rate of cutaneous complications reported from 19 trials was one event per eight weeks of sensor wear-time of which 1.5% were considered severe. The most common cutaneous complications were wear-related erythema, itching, and induration. Although skin irritations were the most common cause of CGM/FGM discontinuation, most users experienced less pain or discomfort with CGM/FGM than capillary blood glucose testing. Future technological advances may reduce, but not eliminate cutaneous complications. CONCLUSION: The incidence rate of reported cutaneous complications with CGM/FGM use from the available literature is low, with one event per eight weeks of sensor wear-time. Reported complication severity was also low, leading to low rates of CGM/FGM discontinuation. However, there appear to be discrepancies between reporting in trial and observational data. Greater constancy in reporting is necessary to understand the frequency of this issue.

The formation of perianchor fluid associated with various suture anchors used in rotator cuff repair: all-suture, polyetheretherketone, and biocomposite anchors.

AIMS: The aim of this study was to compare the osseous reactions elicited by all-suture, polyetheretherketone (PEEK), and two different biodegradable anchors used during rotator cuff repair. PATIENTS AND METHODS: Transosseous-equivalent rotator cuff repair was performed in 73 patients. The patients were divided into two groups, in both of which two different medial-row anchors were used. In group 1, anchor A comprised 30% ß-tricalcium phosphate (TCP) + 70% fast-absorbing poly lactic-co-glycolic acid copolymer (85% polylactic acid enantiomers + 15% polyglycolic acid) and anchor B comprised all-sutures. In group 2, anchor C comprised 23% micro ß-TCP + 77% polylactic acid enantiomers and anchor D comprised PEEK polymer. There were 37 patients in group 1 and 36 patients in group 2. The presence and severity of fluid collection around anchors and healing of the rotator cuff were assessed using MRI scans, approximately one year postoperatively. The severity of the collection was graded as 0 (no perianchor fluid signal), 1 (minimal perianchor fluid), 2 (local collection of fluid), 3 (fluid collection around the whole length of the anchor but of a diameter less than twice the anchor diameter), or 4 (fluid collection around the whole length of the anchor and of a diameter greater than twice the anchor diameter). RESULTS: A perianchor fluid signal was seen in three patients (8.1%) with anchor A, four (10.8%) with anchor B, 15 (41.7%) with anchor C, and 15 (41.7%) with anchor D. The severity of the collection around anchor was grade 2:1:0:0 for anchor A, grade 2:2:0:0 for anchor B, grade 12:2:0:1 for anchor C, and grade 11:3:0:1 for anchor D (grade 1:2:3:4, respectively). The prevalence and severity of fluid formation was not significantly different between anchors A and B, and anchors C and D. However, on intergroup analysis, there were significant differences for the prevalence and severity of fluid formation between anchors in group 1 and group 2. The prevalence of failure to heal was not significant in group 1 (seven, 18.9%) or group 2 (nine, 25.0%). There was no relationship between the presence of perianchor fluid and each type of anchor, and the integrity of the rotator cuff repair, in either group. CONCLUSION: Despite the nonabsorbable nature of all-suture and PEEK anchors, all-suture anchors produced less osseous reaction after rotator cuff repair. In deciding which kind of anchor to use, consideration should be given not only to the strength of the initial fixation, but also to the postoperative biological reaction. Cite this article: Bone Joint J 2019;101-B:1506-1511.

Association Between Pseudotumor Formation and Patient Factors in Metal-on-Metal Total Hip Arthroplasty Population.

BACKGROUND: Pseudotumor formation from metal-on-metal (MoM) hip implants is associated with implant revision. The relationship between pseudotumor type and patient outcomes is unknown. METHODS: We retrospectively reviewed patients with a MoM total hip arthroplasty and metal artifact reduction sequence magnetic resonance imaging. Pseudotumors were graded using a validated classification system by a fellowship-trained radiologist. Patient demographics, metal ion levels, and implant survival were analyzed. RESULTS: Pseudotumors were present in 49 hips (53%). Thirty-two (65%) pseudotumors were cystic thin walled, 8 (16%) were cystic thick walled, and 9 (18%) were solid masses. Patients with pseudotumors had high offset stems (P = .030) but not higher metal ion levels. Patients with thick-walled cystic or solid masses were more likely to be symptomatic (P = .025) and were at increased risk for revision (P = .004) compared to patients with cystic lesions. CONCLUSION: Pseudotumor formation is present in 53% of patients with a MoM total hip arthroplasty, of which 40% were asymptomatic. Patients with thick-walled cystic and solid lesions were more likely to be symptomatic and undergo revision.

Adverse reaction to metal debris after small-head diameter metal-on-metal total hip arthroplasty: an increasing concern.

INTRODUCTION:: Failures due to adverse reaction to metal debris (ARMD) have become an area of common focus among surgeons performing hip replacements. Several authors have reported data on the prevalence of these masses, in both symptomatic and asymptomatic patients after either large-diameter head metal-on-metal (MoM) total hip arthroplasty (THA) or hip resurfacing arthroplasty, with a large variability of rate. To our knowledge, few data are reported on the association of this lesion with the use of small-head diameter MoM. METHODS:: 15 hips that were revised for ARMD in small-head MoM THA were included in this study. We focused our attention on the difficulties of diagnosis and treatment and also on the histologic aspects of the harvested pathologic tissue. RESULTS:: The histological examination of our cases showed a presence of lymphocytic infiltrate suggesting a delayed hypersensitivity reaction to the metal of type IV (ALVAL), but different from each other in term of the prevalence of the cellular component. Osteolysis and severe soft tissue damage were also observed. Revision resulted in remission of the lesion and successful implant. CONCLUSIONS:: Our observation suggests that the evidence of ARMD should be considered even in case of small-head MoM arthroplasty and therefore these patients should be followed scrupulously with 2nd level diagnostic tools such as magnetic resonance imaging with metal artifact reduction sequence (MARS-MRI) and metal ion levels at least once. Further investigations are necessary to establish the real prevalence of this phenomenon in the whole population of small-head MoM THAs.

MRI Findings in Patients After Small-Head Metal-on-Metal Total Hip Arthroplasty with a Minimum Follow-up of 10 Years.

BACKGROUND: Concern has been raised about the late onset of adverse reactions to metal debris (ARMD) in patients with a small-head metal-on-metal total hip replacement. The aims of this study were to assess the frequency and characteristic appearance of ARMD in patients with a small-head (28-mm) metal-on-metal total hip replacement and elevated blood ion levels (>1 µg/L) after a minimum follow-up of 10 years and to analyze the possible risk factors associated with the prevalence of these lesions. METHODS: In the present study, we used metal artifact reduction sequence magnetic resonance imaging (MARS MRI) to investigate the cases of 53 patients (66 hips) with a small-head (28-mm) metal-on-metal total hip replacement and elevated blood ion levels at a mean follow-up interval of 15.5 years (range, 10.6 to 19.3 years). Whole blood metal ion levels (cobalt and chromium), clinical outcome scores (Harris hip score), and radiographs were obtained for each patient. Tissue samples from patients who had revision surgery were histologically examined. RESULTS: MARS MRI revealed ARMD in 27 hips (41%). Most hips with ARMD (67%) were asymptomatic. ARMD were generally small, with a median lesion size of 2.3 cm (range, 0.3 to 71.4 cm) and predominantly cystic in nature. Multivariate regression analysis revealed positive correlation between cobalt ion levels and the presence of ARMD. In this case series, the risk for the development of ARMD was 2.87 times higher for every 1 µg/L increase of blood cobalt ion concentration (95% confidence interval, 1.01 to 8.17; p = 0.048). CONCLUSIONS: In this case series, ARMD were seen in 41% of the hips following small-head metal-on-metal total hip arthroplasty at long-term follow-up, and most patients with ARMD were asymptomatic. Blood cobalt ion levels could be identified as a risk factor for ARMD. However, ARMD also occurred in patients with low metal ion levels. Further studies are necessary to investigate the role of ARMD in asymptomatic patients with this bearing type. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Which factors influence the rate of failure following metal-on-metal hip arthroplasty revision surgery performed for adverse reactions to metal debris? an analysis from the National Joint Registry for England and Wales.

AIMS: To determine the outcomes following revision surgery of metal-on-metal hip arthroplasties (MoMHA) performed for adverse reactions to metal debris (ARMD), and to identify factors predictive of re-revision. PATIENTS AND METHODS: We performed a retrospective observational study using National Joint Registry (NJR) data on 2535 MoMHAs undergoing revision surgery for ARMD between 2008 and 2014. The outcomes studied following revision were intra-operative complications, mortality and re-revision surgery. Predictors of re-revision were identified using competing-risk regression modelling. RESULTS: Intra-operative complications occurred in 40 revisions (1.6%). The cumulative five-year patient survival rate was 95.9% (95% confidence intervals (CI) 92.3 to 97.8). Re-revision surgery was performed in 192 hips (7.6%). The cumulative five-year implant survival rate was 89.5% (95% CI 87.3 to 91.3). Predictors of re-revision were high body mass index at revision (subhazard ratio (SHR) 1.06 per kg/m2 increase, 95% CI 1.02 to 1.09), modular component only revisions (head and liner with or without taper adapter; SHR 2.01, 95% CI 1.19 to 3.38), ceramic-on-ceramic revision bearings (SHR 1.86, 95% CI 1.23 to 2.80), and acetabular bone grafting (SHR 2.10, 95% CI 1.43 to 3.07). These four factors remained predictive of re-revision when the missing data were imputed. CONCLUSION: The short-term risk of re-revision following MoMHA revision surgery performed for ARMD was comparable with that reported in the NJR following all-cause non-MoMHA revision surgery. However, the factors predictive of re-revision included those which could be modified by the surgeon, suggesting that rates of failure following ARMD revision may be reduced further. Cite this article: Bone Joint J 2017;99-B:1020-7.

Systematic Screening of Adverse Reactions to Metal Debris after Recap-M2A-Magnum Metal-on-Metal Total Hip Arthroplasty.

BACKGROUND AND AIMS: An adverse reaction to metal debris is a known complication after large diameter head metal-on-metal total hip arthroplasty. However, the failure rate varies depending on the implant design. Therefore, we investigated the prevalence of adverse reaction to metal debris, as well as the symptoms and risk factors after undergoing a ReCap-M2a-Magnum large diameter head metal-on-metal total hip arthroplasty. MATERIALS AND METHODS: Between 2005 and 2012, 1188 patients (1329 hips) underwent ReCap-M2a-Magnum total hip arthroplasty at our institution. Systematic screening for adverse reaction to metal debris was arranged using the Oxford Hip Score questionnaire, hip and pelvic radiographs, and assessments of the serum chromium and cobalt ion levels. Clinical evaluation and magnetic resonance imaging were performed for the symptomatic patients, as well as those with either chromium or cobalt ion levels ⩾5 µg/L. The prevalence of adverse reaction to metal debris after ReCap-M2a-Magnum total hip arthroplasty was assessed, and the risk factors for adverse reaction to metal debris were evaluated using logistic regression. The mean follow-up time was 5.2 (0.003-9.1) years. This study was an extension of a previous study conducted at our institution with 80 patients. RESULTS: In total, 33 patients (33 hips, 2.5% of all hips) required a revision operation due to adverse reaction to metal debris. Moreover, 157 hips exhibited definitive adverse reaction to metal debris, but a revision operation was not performed (157 of 1329 hips, 11.8% of all hips). Overall, 190 out of 1329 (14.3%) hips had definitive adverse reaction to metal debris. Pain, subluxation sensation, clicking, swelling, a small head size, and a fair/poor Oxford Hip Score were associated with definitive adverse reaction to metal debris. CONCLUSION: We found a high prevalence of adverse reaction to metal debris in the ReCap-M2a-Magnum total hip arthroplasty patients in this study; however, most of the patients did not require revision operations.

Foreign Body Response to Silicone in Cochlear Implant Electrodes in the Human.

HYPOTHESIS: Silicone as part of a cochlear implant electrode may be responsible for a foreign body response in the human. BACKGROUND: Clinical evidence of a foreign body response to a cochlear implant has been reported. In a previous study, particulate material found within the fibrous sheath and within macrophages surrounding a cochlear implant has been identified as being consistent with platinum. However, to date, there has been no histologic evidence of a role for silicone in this cellular immune response. METHODS: A total of 44 temporal bone specimens from 36 patients were reviewed by light microscopy for evidence of presumed platinum and/or silicone foreign bodies in an extracellular or intracellular location. Identification of cell type involved in phagocytosis of foreign body material was accomplished using CD163 immunostaining. The identity and source of the foreign body material was confirmed using energy-dispersive X-ray spectroscopy and scanning electron microscopy. RESULTS: Evidence for both platinum and silicone was found in all 44 specimens. In three patients, anti-CD 163 immunostaining demonstrated phagocytized platinum and silicone foreign bodies. In five specimens, energy-dispersive X-ray spectroscopy demonstrated that the birefringent foreign bodies were consistent with silicone. Scanning electron microscopy of two electrodes removed from temporal bones demonstrated small cracks, fragmentation, and small circular defects in the silicone carrier. CONCLUSION: Histologic evidence of a foreign body response to the presence of platinum and silicone in a cochlear implant has been demonstrated and may be responsible for some reported delayed failures or extrusion.

Percutaneous bone-anchored hearing implant surgery: inside or outside the line of incision?

The objective of this historical cohort study was to compare soft tissue reactions in adults after bone-anchored hearing implant (BAHI) surgery when the percutaneous implant is placed inside or outside the line of incision. All adult patients who received a percutaneous BAHI between 1 January 2010 and 31 January 2014 in our tertiary referral centre were identified. Patients were selected if operated by two surgeons, who perform the same standardised linear incision technique with one of them placing the implant outside the incision while the other prefers placement inside the line of incision. A total of 202 patients and 211 implants were included in the case analysis. The results showed the registration of a soft tissue reaction Holgers ≥1 in 47 implants (49.0 %) placed outside the incision compared to 70 implants (60.9 %) which were placed inside the line of incision. An adverse soft tissue reaction, Holgers ≥2, was noticed in 17 implants (17.7 %), respectively, 20 implants (17.4 %). No significant differences were found between the two groups for both the presence of soft tissue reactions Holgers ≥1 (p = 0.322) and a Holgers score ≥2 (p = 0.951). During the follow-up three implants were lost (1.4 %) and in 18 of 211 implants one or multiple revisions were performed (8.5 %). In conclusion, this study did not show any differences in the presence of postsurgical (adverse) soft tissue reactions between placement of the percutaneous BAHI inside or outside the line of incision.

Polyurethane foam-covered breast implants: a justified choice?

OBJECTIVE: Even if the safety of the polyurethane prosthesis has been the subject of many studies and professional and public controversies. Nowadays, polyurethane covered implants are very popular in plastic surgery for the treatment of capsular contracture. MATERIALS AND METHODS: We have identified 41 papers (1 is a communication of the FDA) by using search browsers such as Pubmed, Medline, and eMedicine. Eleven manuscripts have been used for an introduction, and the remaining thirty have been subdivided into three tables whose results have been summarized in three main chapters: (1) capsular formation and contracture, (2) complications, (3) biodegradation and cancer risk. RESULTS: (1) The polyurethanic capsule is a well defined foreign body reaction characterized by synovial metaplasia, a thin layer of disarranged collagen fibers and a high vascularization. These features make possible a "young" capsule and a low occurrence of capsular contracture even over a long period (10 years); (2) the polyurethane implants may be difficult to remove but there is no evidence that they cause an increase in the other complications; (3) there is no evidence of polyurethane related cancer in long-term studies (after 5 years). CONCLUSIONS: Polyurethane foam covered breast implants remain a valid choice for the treatment of capsular contracture even if it would be very useful to verify the ease of removal of the prosthesis and to continue investigations on biodegradation products.

Current controversies regarding oncologic risk associated with polypropylene midurethral slings.

Midurethral synthetic slings are the gold standard treatment for stress urinary incontinence. However, recent concerns have been raised regarding a possible association between synthetic midurethral slings and malignancy. The aim of this editorial was to examine the data behind these concerns. After a review of the data, no evidence was found to suggest that polypropylene midurethral slings are associated with a risk of malignancy.ᅟ

Nationwide investigation into adverse tissue reactions to metal debris after metal-on-metal total hip arthroplasty in Japan.

BACKGROUND: Adverse reactions to metal debris (ARMD) after receiving metal-on-metal (MoM) hip implants is a recent concern. However, no epidemiologic study has examined ARMD for MoM hip implants in Japan. The purposes of this study were to research the incidence of ARMD and to identify poorly performing MoM hip implants in Japan. METHODS: From 2000 to 2011, 7 companies provided 23,226 MoM implants in Japan. A questionnaire regarding ARMD was sent to 101 hospitals at which 62% of the 23,226 MoM implants had been used. RESULTS: Replies to the questionnaire were received from 82 hospitals. In these hospitals, surface hip replacement types (SRs) were used in 606 hips and stemmed types were used in 12,961 hips. ARMD were reported in 3 hips (0.5%) with SRs and 160 hips (1.2%) with stemmed types. ARMD in the 3 hips with SRs were asymptomatic and no revisions were performed. Among AMRD with stemmed implants, revision was performed in 83 hips and excision of an ARMD lesion was performed in 3 hips. The remaining 74 hips were asymptomatic and careful follow-up was continued. A significant difference in reoperation rate was evident between SRs (0%) and stemmed types (0.7%). Incidences of ARMD were significantly higher with Ultamet (P = 0.005), Conserve (P < 0.001), and Cormet (P < 0.001) MoM bearing couples than with Metasul bearings. CONCLUSIONS: The incidence of ARMD in large surgical volume hospitals in Japan from 2000 to 2011 was estimated to be 0.5% with SRs and 1.2% with stemmed types. The reoperation rate was significantly higher with stemmed types than with SRs. Three brands of MoM stemmed implants were identified as showing a higher incidence of ARMD.

Foreign body aspiration in children: experience from 2624 patients.

OBJECTIVES: The objective of this study is to analyze the epidemiological, clinical, radiological and endoscopic characteristics of pediatric foreign body aspiration in Algeria. METHODS: In this retrospective study, the results of 2624 children younger than 18 years admitted in our department for respiratory foreign body removal between 1989 and 2012, were presented. Most of them had an ambulatory rigid bronchoscopy. RESULTS: The children (62.34% males and 37.65% females) were aged 4 months to 18 years with 66% between 1 and 3 years. Choking was related in 65% of cases. The delay between aspiration and removal was 2-8 days in 65.8% and within 24 h in 9.2%. In the most cases, the children arrived with cough, laryngeal or bronchial signs and unilateral reduction of vesicular murmur. The examination was normal in 13%. The most common radiologic finding was pulmonary air trapping (40.7%). The aspirated bodies were organic in 66.7%, dominated by peanuts, while sunflower seeds, beans and ears of wheat were the most dangerous. In the other cases, they were metallic or plastic as pen caps and recently scarf pins. The endoscopic removal by rigid bronchoscopy was successful and complete in 97%. Cases with extraction failure (3%) limited to certain FBs, all of them inorganic were assigned to surgery. The complications related to the endoscopic procedure were 0.29% with a mortality of 0.26%. CONCLUSION: Foreign body aspiration is a real public health problem in Algeria. The best way to manage it is an early diagnosis and a rigid bronchoscopy removal under general anesthesia used by fully trained staff. The prevention of this domestic accident should consider the population lifestyle and cultural habits to be more effective.

Plasma gel as a new augmentation material for injection laryngoplasty in rabbit model: histologic analysis.

OBJECTIVES: Currently, a variety of materials are available for the treatment of glottal insufficiency. Ideal injection materials should be inexpensive, easily obtainable, nontoxic, and biocompatible. Plasma gel has recently been developed as an injectable, autologous material used in plastic surgery. The aim of this study was to evaluate the histological changes in rabbit vocal folds (VFs) after an injection of plasma gel, compared with collagen (Artecoll) or hyaluronic acid (Reviderm Intra). STUDY DESIGN: Experimental prospective animal study. SETTING: Animal laboratory. SUBJECTS AND METHODS: Blood samples were collected from 12 New Zealand rabbits. Plasma collected from each rabbit was centrifuged and processed using a gel heating system. All rabbits received a 0.05 ml injection of plasma gel into the right VF, while an equivalent volume of Artecoll or Reviderm Intra was injected into the left VFs of each 6 rabbits randomly. The larynges were collected 2, 4, and 8 weeks after injection, and the tissues were stained for histological analysis. RESULTS: In comparison with left VFs injected with Artecoll or Reviderm Intra, there was significantly less inflammatory response and foreign body reaction in the plasma gel injected right VFs (P < .05). Multinucleated foreign body type giant cells were also more prevalent in the left VFs. There were no quantitative differences in the rates of neovascularization or collagen deposition between groups. CONCLUSION: Plasma gel is a biologically compatible material that may serve as a suitable augmentation material in injection laryngoplasty. Further studies that examine the long-term effects in a larger number of subjects are needed.

Prevalence of adverse reactions to metal debris following metal-on-metal THA.

The purpose of this study was to determine the prevalence of adverse reactions to metal debris (ARMD) following large-diameter metal-on-metal total hip arthroplasty. The authors examined the potential for using magnetic resonance imaging to screen for pseudotumors in 108 hips 2 years postoperatively. Serum cobalt and chromium concentrations were measured in 80 hips that underwent unilateral total hip arthroplasty. The authors considered pseudotumors and aseptic lymphocyte-dominated vasculitis-associated lesions to be ARMD and compared metal ion levels between hips with ARMD (ARMD group) with hips with no ARMD (non-ARMD group). Magnetic resonance imaging revealed pseudotumors in 9 patients (10 hips, 9%). Five of these 10 hips were symptomatic and underwent revision surgery. Two other patients underwent revision surgery due to symptomatic cup loosening with aseptic lymphocyte-dominated vasculitis-associated lesions. Ten patients (12 hips) had ARMD. Serum cobalt and chromium concentrations were significantly higher in hips with ARMD than hips without ARMD. Other factors, including age, body mass index, sex, clinical score, acetabular cup inclination angle, and femoral head diameter, were not significantly different between the groups. Elevated metal ion levels suggest that ARMD is associated with increased metal wear. Magnetic resonance imaging provides sensitive screening for pseudotumors following metal-on-metal total hip arthroplasty.

Incidence of pseudotumor and acute lymphocytic vasculitis associated lesion (ALVAL) reactions in metal-on-metal hip articulations: a meta-analysis.

We systematically reviewed the peer-reviewed literature to determine a pooled estimate of the incidence of pseudotumor and acute lymphocytic vasculitis associated lesions (ALVAL) in adult patients with primary metal-on-metal (MoM) total hip arthroplasty or resurfacing. Fourteen eligible articles were identified, with a total of 13,898 MoM hips. The incidence of pseudotumor/ALVAL ranged from 0% to 6.5% of hips with a mean follow-up ranging from 1.7 to 12.3 years across the studies. The pooled estimated incidence of pseudotumor/ALVAL is 0.6% (95% CI: 0.3% to 1.2%). The rate of revision for any reason ranged from 0% to 14.3% of hips, with a pooled estimate of 3.9% (95% CI: 2.7% to 5.3%).

Forgotten ureteral stents: who's at risk?

The sequelae from forgotten stents carry significant morbidity and costs. In this study, we attempt to identify potential risk factors that may make patients less likely to follow up for stent removal so that more effective prevention efforts may be directed at these persons. A single-institution retrospective analysis of 187 consecutive patients who had stents placed between January 2010 and December 2010 was performed. Chart review was conducted to see if patients had undergone stent removal beyond the intended maximal stent life (MSL). Patients who were lost to follow-up were contacted to determine if stents were overdue. Logistic regression was performed to determine risk factors. Of the 187 patients who had stents placed, 147 had the stent removed before MSL and 28 had stents removed after the MSL. Twelve patients could not be contacted and were excluded from the analysis. Within our cohort of 175 patients, 48% were males, 73% were minorities (33% Latino, 30% Black, 8% Asian, and 2% Native American), 39% did not speak English, 79% were unemployed, 73% were uninsured, and 35% were married. Among the patients with forgotten stents, 68% were male, 64% were minorities (32% Latino, 29% Black, 4% Native American, and 0% Asian), 82% were unemployed, 39% did not speak English, 93% were uninsured, and 43% were married. Multivariate regression analysis demonstrated that uninsured patients (odds ratio [OR], 6.3; 95% confidence interval [CI], 1.4-28.2; P value 0.01) and males (OR, 2.8; CI, 1.2-6.8; P=0.02) had statistically significant associations with forgotten stents. Men were 2.8 times more likely to have forgotten stents than females. Patients without health insurance were six times more likely to have forgotten stents than patients with insurance. As efforts are made to prevent forgotten stents, increased attention should be given to these higher-risk patient populations.