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The incidence of revision total knee arthroplasty (TKA) has grown tremendously the past decade, and all projections suggest that it will continue to increase during the next 25 years. Although primary TKA remains one of the most successful orthopedic procedures, revision TKA has not as well. Failure rates for revision TKA remain significantly higher than those for primary TKA. New revision systems should be developed with new implants and instrumentation to address the difficulties frequently experienced with revision TKA. In this article, design surgeons report on the development of a new system and the early clinical experience with its use. The researchers believe that this new system is easy to use and facilitates accurate implantation, which could improve revision TKA outcomes. [ABSTRACT FROM AUTHOR]

In the past, treatment of knee osteoarthritis has been limited to unicompartmental knee replacement or total knee arthroplasty (TKA). Neither option is well suited for the active patient with midstage osteoarthritis of the medial and patellofemoral compartments. Now an alternative treatment is available that targets the diseased area without sacrifice of normal bone or both the cruciate ligaments. Minimally invasive surgical techniques are easily used, which reduces tissue trauma and results in a quicker recovery than TKA. Bicompartmental replacement offers decreased pain, stability through normal ligament structure, and the retention of normal bone for patients with medial and patellofemoral osteoarthritis. [ABSTRACT FROM AUTHOR]

Cystic Fibrosis (CF) is the most common inherited disorder and is characterized by an inflammatory phenotype. Here, we found that in bronchial epithelium reconstituted form lung tissue biopsies from patients with CF, the RNA-binding protein tristetraprolin (TTP), a key regulator of inflammation, is dysregulated in cells that strongly express cytokines and interleukins. TTP activity is regulated by extensive post-translational modifications, particularly phosphorylation. We found that in addition to mRNA downregulation, phosphorylated TTP (which cannot bind to mRNA) accumulated in CF cultures, suggesting that the imbalance in TTP phosphorylation status could contribute to the inflammatory phenotype in CF. We confirmed TTP destabilizing role on IL8 mRNA through its 3'UTR sequence in CF cells. We next demonstrated that TTP phosphorylation is mainly regulated by MK2 through activation of ERK, which also was hyperphosphorylated. TTP is considered a mRNA decay factor with some exception, and we present a new positive role of TTP in CF cultures. We determined that TTP binds to specific ARE motifs on the 3'UTR of mRNA sequences and also, for the first time, to the 3'UTR of Cystic Fibrosis Transmembrane Conductance Regulator ( CFTR ) where TTP binding stabilizes the mRNA level. This study identified new partners that can be targeted in CF and proposes a new way to control CFTR gene expression.

Background: Psoriasis affects 0.2-0.7 % of children and is associated with obesity. Published studies have been conducted in hospital settings (tertiary care). The PsoLib study evaluated childhood psoriasis in private practice (secondary care) in terms of epidemiology, clinical aspects and comorbidities., Patients and Methods: This was a non-interventional, cross-sectional, multicenter study of children with psoriasis performed by 41 dermatologists working in private practice. The clinical and therapeutic aspects and comorbidities were systemically evaluated. We compared data to the χ-Psocar study performed in hospitals using the same methodology., Results: In all, 207 children (girls: 60.4 %; mean age: 10.5±4.2 years) were included. Scalp psoriasis (40.6 %) was the most frequent clinical type, while plaque psoriasis represented 26 % of cases. Nail, tongue, and arthritic involvement were rare. Less than 1 % of children suffered from hypertension, diabetes or dyslipidemia, but 16.4 % were overweight and 7.0 % were obese. Severity (PG≥4 at peak) was associated with excess weight (P=0.01)., Conclusion: Scalp psoriasis is the most frequent clinical type of psoriasis in childhood. Comorbidities and extracutaneous localization are rare. Even in private practice, the severity of the disease is associated with excess weight., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Total knee arthroplasty is a predictable operation. Unfortunately, there is a subset of patients who do not do well and require revision surgery within the first 5 years. The purpose of the current study was to analyze the mechanisms of failure in patients who had revision surgery within 5 years of their index arthroplasty. Between 1986 and 1999, 440 patients with total knee arthroplasties were referred for revision surgery. An analysis of patients in whom the arthroplasties failed within 5 years of the index arthroplasty and the reasons for early failure were documented. Of the 440 patients who had revision surgery, 279 (63%) had revision surgery within 5 years of their index arthroplasty: 105 of the 279 patients with early failures (38%) had revision surgery because of infection; 74 (27%) had revision surgery because of instability; 37 (13%) had revision surgery because of failure of ingrowth of a porous-coated implant; 22 (8%) had revision surgery because of patellofemoral problems; and 21 (7%) had revision surgery because of wear or osteolysis. Only eight of the 279 patients with early failures (3%) had revision surgery because of aseptic loosening of a cemented implant. The remaining 12 patients had revision surgery because of miscellaneous problems. Host factors may prevent infection from ever being eradicated totally. The two other major patterns of failure in this series were failure of cementless fixation and instability. If all of the arthroplasties in the patients in this early failure group would have been cemented routinely and balanced carefully, the total number of early revisions would have decreased by approximately 40%, and the overall failures would have been reduced by 25%.

Studies showing that degenerative spondylolisthesis is 4 to 5 times more common in females than in males have suggested that hormonal influences account for this gender difference. Estrogen has been shown to play a role in other instabilities, such as those of the anterior cruciate ligament and the shoulder capsular ligaments, and estrogen receptors have been identified in these tissues. We wanted to assess facet joint capsular ligaments for the presence of such receptors. Accordingly, we collected facet joint capsular ligaments from 14 consecutive patients undergoing lumbar spinal fusion. Tissue sample analysis was performed by immunohistology using prediluted estrogen monoclonal antibody (Vantana) and automated immunostaining on a Vantana instrument. None of the specimens analyzed contained estrogen receptors. We conclude that, though degenerative spondylolisthesis may have hormonal influences, estrogen seems not to play a direct role in its development.

Eleven bony pelves were studied in an attempt to find an ideal approach for needle placement into the sacroiliac joint and to describe the unique anatomy of the sacroiliac joint relative to sacroiliac joint injection. A posterior approach starting 2 cm to 3 cm inferior to the posterior superior iliac spine, angled 20 degrees to 30 degrees laterally, relative to the sagittal plane, and 10 degrees to 20 degrees inferiorly, relative to the transverse plane, was found to be the best approach to the intra-articular portion of the sacroiliac joint.

Study Design: Morphometric, radiographic, and computed tomographic evaluation of the pedicle of the first sacral vertebra was performed, and the pedicle's spatial relation with the posterior surface of the ilium was defined., Objectives: To facilitate accurate localization of the entry site of the iliosacral pedicular screw on the posterior surface of the ilium, to provide optimal length and direction of iliosacral screw placement, and to investigate the feasibility of inserting two screws through the first sacral vertebral pedicle for unstable posterior pelvic fixation., Methods: Anterior and posterior pedicular height, pedicular depth, alar depth, and posterior alar height of S1 vertebrae were measured in 11 body pelves bilaterally. Sacral pedicular height was also measured on the outlet view radiograph as visualized during intraoperative fluoroscopy, and compared with actual anatomic pedicular height. The distance from the posterior limit of the ilium to the S1 ala, pedicle, and pedicle axis, and the distance between the outer table of the ilium and anterior cortex of the sacrum were measured on axial computed tomography scans. Finally, parasagittal sections of the sacral were made to assess the safety zone for placement of two pedicular screws into the vertebral body., Results: The mean anterior and posterior pedicular heights were 30.2 and 26.1 mm, respectively. The depths of the pedicle and ala were 27.8 and 45.8 mm, respectively. The mean posterior alar height was 28.7 mm. The mean first sacral pedicular height measured on the outlet-view radiographs was 20 mm, which was significantly less (P < 0.0001) than the actual gross anatomic pedicular height. The mean distance from the posterior limit of the ilium to the pedicle axis projection point on axial computed tomography scans was 32.5 mm, and the mean distance from this point to the greater sciatic notch was 38.6 mm. The mean distance between the outer table of the ilium and the anterior cortex of the sacrum was 105.2 mm. The safety margin for two closely inserted pedicular screws was only 4 to 6 mm., Conclusions: This study suggests that placement of one screw through the S1 pedicle into the vertebral body is safer, and routine placement of two sacral pedicular screws may be difficult. The optimal starting point for placement of single iliosacral screw is 3 to 3.5 cm anterior to the posterior border of the iliac bone in the sagittal plans, and 3.5 to 4 cm cephalad to the greater sciatic notch. The screw should be directed perpendicular to the outer surface of the table from this entry point. The safe length of the iliosacral pedicular screw is up to 80 mm.

Study Design: This study analyzed anatomic parameters between the midpoint of cervical vertebral lateral masses as seen on the superficial, posterior aspect of the mass and cervical nerve roots. Posterior cervical dissection was performed, with the midpoint of the lateral masses kept intact and the nerve roots exposed., Objective: To quantitatively determine the location of the cervical nerve roots and the transverse foramina, indicating vertebral artery placement relative to the posterior aspect of the cervical spine., Summary of Background Data: Posterior plate-screw fixation of the cervical spine has been widely used to treat unstable fractures of the cervical spine. However, injury to the spinal nerve roots during the procedure remains an important concern. No previous anatomic study regarding the location of the cervical nerve roots relative to the posterior aspect of the cervical spine has been reported., Methods: Fifteen specimens were obtained for study of the cervical spine. Laminectomy and partial removal of the superior and inferior articular facets then were performed on C2-C3 through C7-T1 to expose the nerve roots and dura. Photographs, containing a reference scale, were taken simultaneously perpendicular to the sagittal and transverse planes of the specimen. Using enlarged versions of the photographs, independent measurements by several observers were taken from the superficial, posterior center of each lateral mass to the nerve root superiorly and inferiorly, and to the lateral limits of the dura. Vertebrae from an additional 20 spines were examined to determine the position of the transverse foramina relative to the lateral mass of the vertebrae., Results: The results showed that for C3-C7, the average distance from the superficial, posterior center of the lateral mass to the nerve root superiorly was 5.7 +/- 1.5 mm. Inferiorly, the average distance was 5.5 +/- 0.8 mm. The average distance from the lateral mass to the spinal cord dura was 9.2 +/- 1.4 mm, and the average medial angle of the nerve root was 76.3 degrees +/- 4.4 degrees. For cervical vertebrae C3-C5, the transverse foramina were situated medial to the posterior center of the lateral mass. At the C6 level, the transverse foramina were situated anterior to the posterior midpoint of the lateral mass., Conclusion: This study demonstrates that the posterior midpoint of the lateral mass is a safe point for initiating screw insertion.

Study Design: This study assessed numerous structural features of the second cervical vertebra (C2), describing the projection point of the pedicle on its posterior aspect., Objectives: Evaluation of the specimens included quantitative description of 18 linear and four angular parameters, which then were correlated between male and female specimens. The point of projection of the C2 pedicle axis was described with an emphasis on a perspective relevant to a posterior approach., Summary of Background Data: The literature regarding the anatomy of the axis focuses mainly on the dens. Very little research regarding the quantitative study of the C2 pedicle has been reported., Methods: Fifty dry C2 cervical vertebrae (30 male, 20 female) were obtained for anatomic measurements. Anatomic evaluation focused on the pedicle, vertebral body, dens, superior facet, and vertebral canal. All measurements were made using calipers and a standard rule linear measurements and a goniometer for angular measures. Based on the measurement of 50 specimens, including 18 linear and four angular parameters, the mean, range, and standard deviation were calculated for all of the specimens and for male and female separately., Results: A significant difference was found to exist for 11 of 18 linear measurements and one of four angular parameters. The projection point of the pedicle axis on the posterior aspect of the lateral mass was described with an emphasis on a perspective relevant to a posterior surgical approach. The location of the projection point of the pedicle axis was found to be 5.4 +/- 1.2 mm inferior to the horizontal line, and 7.2 +/- 1.3 mm lateral to the vertical line. The pedicle axis was found to lie at 33 degrees in the medial direction and 20 degrees in the superior direction form the point of pedicle axis projection., Conclusions: When the techniques described here are used, the findings may be helpful in cases involving C2 when surgical intervention and instrumentation are desired.

The method described here allows to classify anaerobic bacteria isolated from clinical specimens in four categories of sensitivity or resistance to 8 antibiotics. Previous experiments using eight reference strains led to choose the pre-reduced Schaedler broth supplemented with hemin, vitamin K1, and 0.07 p. cent agar. For each group of three concentrations of antibiotics, a check sample could confirm the growth of the bacteria without antibiotic. Very few minor discrepancies were observed when the results of the classification in categories were compared to the MIC in Wilkins-Chalgren solid medium as reference method. These discrepancies were related to the inoculum and specially for fast-growing species as Bacteroides fragilis or Clostridium. The use of an inoculum standardized to 0.5 MF for slow-growing species and 0.5 MF diluted hundred fold for fast-growing one confirmed the good correlation between the two methods in a short delay.

The authors chose the problem of the isolation of bacteroides fragilis in pathological samples to present a method of identification of strict anaerobic gram negative bacteria, suitable for use in a routine bacteriological laboratory. A selection of 20 strains led them to study the mean inhibitory concentration of these germs with regard to antibiotics. From this study, two groups were obtained: one of low activity, the other of greater activity in vitro, in which one may note certain tetracyclines, clindamycin and metronidazole.

The author tested parallely 35 Bacteroides fragilis strains by the agar diffusion method and disk technique. A notable discrepancy appears between these two procedures. No regression line can be constructe and the inhibition diameter measurement is unable to class the strain in "susceptible" or "resistant". A literature review on this theme shows that the dissociation between these two techniques were more frequent with anaerobic strains than aerobic for SMX + TMP as others antibiotics. The MIC determination by an agar dilution is the only able to these studies.

The minimum inhibitory concentrations (MIC) of nalidixic acid were determined for thirty-four strains of Clostridium sp. by an agar dilution technique. The MIC range of Clostridium perfringens ran from 0.03 microgram/ml to 64 microgram/ml, according to a bimodal distribution. One half of the strains was inhibited by 0.25 microgram/ml. 64 microgram/ml was able to inhibit all the strains tested. The author suggests a systematic utilization of media with and without 40 microgram/ml nalidixic acid. These two media were parallely inoculated with clinical specimens where anaerobic bacteria were suspected, and allowed the isolation of gram negative anaerobes.

The authors have used two different methods for the identification of 45 strains of stric anaerobic gram negative rods: a study of biochemical characters by the API 20 anaerobic kit, and system proposed by SUTTER and FINEGOLD (susceptibility to discs loaded with antibiotics associated with some simple biochemical characters). A good correlation has been observed between those two techniques. However, a precise diagnostic can be given only by a whole study of biochemical characters, as proposed by the system API 20 Anaerobic.