Assessment of Pull-out Forces in TEVAR and ANACONDA FEVAR Combination and Early Clinical Results: Creation of a Proximal Landing Zone for FEVAR in Patients with Extent I and Extent IV TAAAs

Background: transarticular screw (TAS) fixation without a supplementary posterior construct, even in rheumatoid arthritis (RA) patients, provides sufficient stability with acceptable clinical results. Here, we present our experience with 15 RA patients who underwent atlantoaxial (AA) TAS fixation without utilizing a supplementary posterior fusion. Methods: To treat AA instability, all 15 RA patients underwent C1–C2 TAS fixation without a supplementary posterior construct. Patients were followed for at least 24 months. Pre- and postoperative sagittal measures of C1– C2, C2–C7, and C1–C7 angles, atlanto-dens interval (ADI), posterior atlanto-dens interval (PADI), and adjacent segment (i.e., C2–C3) anterior disc height (ADH) were retrospectively recorded from lateral X-ray imaging. The presence or absence of superior migration of the odontoid (SMO), cervical subaxial subluxation, C1–C2 bony fusion, screw pull-out, and screw breakage were also noted. Results: There was little difference between the pre- and postoperative studies regarding angles measured. Following TAS fixation, the mean ADI shortened, and mean PADI lengthened. There was no difference in the mean measures of C2–C3 ADH. There was no evidence of SMO pre- or postoperatively. Two patients developed anterior subluxation at C5–C6; one of the two also developed anterior subluxation at C2–C3. All patients subsequently showed C1–C2 bony fusion without screw pull-out or breakage. Conclusion: In RA patients who have undergone C1–C2 TAS fixation, eliminating a supplementary posterior fusion resulted in adequate stability.

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Second-Look Arthroscopic Assessment and Clinical Results of Modified Pull-Out Suture for Posterior Root Tear of the Medial Meniscus

Knee Surgery and Related Research ◽

10.5792/ksrr.2014.26.2.106 ◽

2014 ◽

Vol 26 (2) ◽

pp. 106-113 ◽

Cited By ~ 26

Author(s):

Jin-Ho Cho ◽

Jae-Gwang Song

Keyword(s):

Medial Meniscus ◽

Clinical Results ◽

Posterior Root ◽

Root Tear ◽

Posterior Root Tear ◽

Pull Out ◽

Second Look ◽

Pull Out Suture

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Late surgical conversions after abdominal endovascular aortic repair: underlying mechanisms, clinical results and strategies for prevention

Interactive CardioVascular and Thoracic Surgery ◽

10.1093/icvts/ivz207 ◽

2019 ◽

Vol 29 (6) ◽

pp. 944-949

Author(s):

Andrzej Juraszek ◽

Bartosz Rylski ◽

Stoyan Kondov ◽

Johannes Scheumann ◽

Maximilian Kreibich ◽

...

Keyword(s):

Aortic Rupture ◽

Graft Infection ◽

Endovascular Aneurysm Repair ◽

Clinical Results ◽

Late Complications ◽

Landing Zone ◽

Trade Offs ◽

Abdominal Aortic ◽

The Mean

Abstract OBJECTIVES Our goal was to report our results of late surgical conversion after endovascular aneurysm repair (EVAR). METHODS Variables analysed included baseline data, preinterventional anatomy, type of endovascular intervention, indications for conversion, operative technique, postoperative complications and follow-up survival rate. RESULTS Between April 2011 and May 2018, 16 patients with late complications after EVAR underwent open surgical conversion at our institution. The mean age was 73.6 [standard deviation (SD) 8.9] years. There were 3 (18.8%) female patients. In 15 patients, the indication for primary EVAR was abdominal aortic aneurysm, and in 1 patient, chronic abdominal aortic dissection. Five patients underwent secondary EVAR service interventions for endoleak treatment between the index EVAR and the final secondary surgical conversion. Thirteen patients underwent surgery in an elective setting and 3 patients underwent emergency surgery. The mean time from EVAR to open surgical conversion was 6.31 (SD 4.0) years (range 1.2–16.0 years). The most common indication for conversion was endoleak formation (n = 12, 75%), followed by 3 cases of aortic rupture (1 patient with primary type 1 endoleak) and 2 cases of stent graft infection—1 with and 1 without an aortoduodenal fistula. One patient died during emergency open surgery of cardiopulmonary instability. Three patients developed postoperative renal dysfunction with recovery of their renal function before discharge. The in-hospital mortality rate was 12.5%. The median follow-up was 16.5 months (interquartile range 21 months). Freedom from death and aortic reintervention was 100%, respectively. After careful review of the index computed tomography scans for EVAR, the majority of failures could have been anticipated due to trade-offs with regard to length, diameter, morphology, shape and angulation of the proximal and/or distal landing zone. CONCLUSIONS Despite being a challenging operation, late surgical conversion after EVAR yields excellent results with regard to outcome and freedom from the need for further aortic interventions. An anticipative strategy adhering to current recommendations for using or refraining from using EVAR in patients with anatomical challenges will help reduce the need for secondary surgical conversions and keep them to minimum.

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The influence of heat treatment on the fiber/matrix interface in a SiC-reinforced glassceramic

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105771 ◽

1988 ◽

Vol 46 ◽

pp. 742-743

Author(s):

E. Bischoff ◽

O. Sbaizero

Keyword(s):

Heat Treatment ◽

Aluminum Silicate ◽

Lithium Aluminum ◽

Interfacial Region ◽

Specimen Preparation ◽

Crack Wake ◽

Pull Out ◽

Annealed Material ◽

Ultrasonic Drilling ◽

Fiber Matrix Interface

Fiber or whisker reinforced ceramics show improved toughness and strength. Bridging by intact fibers in the crack wake and fiber pull-out after failure contribute to the additional toughness. These processes are strongly influenced by the sliding and debonding resistance of the interfacial region. The present study examines the interface in a laminated 0/90 composite consisting of SiC (Nicalon) fibers in a lithium-aluminum-silicate (LAS) glass-ceramic matrix. The material shows systematic changes in sliding resistance upon heat treatment.As-processed samples were annealed in air at 800 °C for 2, 4, 8, 16 and 100 h, and for comparison, in helium at 800 °C for 4 h. TEM specimen preparation of as processed and annealed material was performed with special care by cutting along directions having the fibers normal and parallel to the section plane, ultrasonic drilling, dimpling to 100 pm and final ionthinning. The specimen were lightly coated with Carbon and examined in an analytical TEM operated at 200 kV.

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Characterization of interfaces in CVD-coated nicalon fiber-reinforced SiC

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154755 ◽

1989 ◽

Vol 47 ◽

pp. 556-557

Author(s):

K.L. More ◽

R.A. Lowden

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Chemical Vapor ◽

Chemical Vapor Infiltration ◽

Frictional Stress ◽

Fiber Reinforced ◽

Pull Out ◽

Carbon Coated ◽

Fiber Matrix

The mechanical properties of fiber-reinforced composites are directly related to the nature of the fiber-matrix bond. Fracture toughness is improved when debonding, crack deflection, and fiber pull-out occur which in turn depend on a weak interfacial bond. The interfacial characteristics of fiber-reinforced ceramics can be altered by applying thin coatings to the fibers prior to composite fabrication. In a previous study, Lowden and co-workers coated Nicalon fibers (Nippon Carbon Company) with silicon and carbon prior to chemical vapor infiltration with SiC and determined the influence of interfacial frictional stress on fracture phenomena. They found that the silicon-coated Nicalon fiber-reinforced SiC had low flexure strengths and brittle fracture whereas the composites containing carbon coated fibers exhibited improved strength and fracture toughness. In this study, coatings of boron or BN were applied to Nicalon fibers via chemical vapor deposition (CVD) and the fibers were subsequently incorporated in a SiC matrix. The fiber-matrix interfaces were characterized using transmission and scanning electron microscopy (TEM and SEM). Mechanical properties were determined and compared to those obtained for uncoated Nicalon fiber-reinforced SiC.

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Advances in ultramicrotomy for physical sciences applications

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149386 ◽

1993 ◽

Vol 51 ◽

pp. 710-711

Author(s):

G. McMahon ◽

T. Malis

Keyword(s):

Particle Surface ◽

Zeolite Catalysts ◽

Physical Sciences ◽

Pull Out ◽

Large Particles ◽

Novel Applications ◽

Metal Wires ◽

Frequent Problem ◽

Specific Orientation ◽

Diamond Knife

As with all techniques which are relatively new and therefore underutilized, diamond knife sectioning in the physical sciences continues to see both developments of the technique and novel applications.Technique Developments Development of specific orientation/embedding procedures for small pieces of awkward shape is exemplified by the work of Bradley et al on large, rather fragile particles of nuclear waste glass. At the same time, the frequent problem of pullout with large particles can be reduced by roughening of the particle surface, and a proven methodology using a commercial coupling agent developed for glasses has been utilized with good results on large zeolite catalysts. The same principle (using acid etches) should work for ceramic fibres or metal wires which may only partially pull out but result in unacceptably thick sections. Researchers from the life sciences continue to develop aspects of embedding media which may be applicable to certain cases in the physical sciences.

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