scholarly journals DIRECT PEDICLE SCREW INSERTION PULLOUT STRENGTH

2021 ◽  
Vol 29 (4) ◽  
pp. 203-206
Author(s):  
RÔMULO PEDROZA PINHEIRO ◽  
ARIANE ZAMARIOLI ◽  
THIBAULT CHANDANSON ◽  
KERI GEORGE ◽  
ANTONIO CARLOS SHIMANO ◽  
...  
Keyword(s):  
Test Machine ◽  
Pullout Strength ◽  
Insertion Technique ◽  
Level Of Evidence ◽  
Surgical Guidance ◽  
Pilot Hole ◽  
Screw Insertion ◽  
Pullout Tests ◽  
Experimental Group

ABSTRACT Objective: Study the in vitro pullout strength of SpineGuard/Zavation Dynamic Surgical Guidance Z-Direct Screw (DSG Screw), a screw pedicle designed to be inserted using a direct insertion technique. Methods: DSG Screws of 5.5 mm and 6.5 mm were introduced into polyurethane blocks with a density of 10 PCF (0,16 g/cm3). According to the experimental group, screws were inserted without pilot hole, with pilot without tapping, undertapping and line-to-line tapping. Screw pullout tests were performed using a universal test machine after screw insertion into polyurethane blocks. Results: Screws inserted directly into the polyurethane blocks without pilot hole and tapping showed a statistically higher pullout strength. Insertion of the screw without tapping or with undertapping increases the pullout screw strength compared to line-to-line tapping. Conclusion: DSG Screw showed the highest pullout strength after its insertion without pilot hole and tapping. Level of Evidence V, Expert Opinion.

Pullout Strength of Screws in Foal Third Metacarpal Bone after Overdrilling a 4.5 mm Hole

1998 ◽  
Vol 11 (04) ◽  
pp. 200-204 ◽  
Author(s):  
K. Kelly ◽  
G. S. Martin ◽  
D. J. Burba ◽  
S. A. Sedrish ◽  
R. M. Moore
Keyword(s):  
Cortical Bone ◽  
Metacarpal Bone ◽  
Pullout Strength ◽  
Cancellous Screw ◽  
Bone Screw ◽  
Screw Insertion ◽  
Holding Power ◽  
Cortical Screw ◽  
Metaphyseal Bone

SummaryThe purpose of the study was to determine and to compare the in vitro pullout strength of 5.5 mm cortical versus 6.5 mm cancellous bone screws inserted in the diaphysis and metaphysis of foal third metacarpal (MCIII) bones in threaded 4.5 mm cortical bone screw insertion holes that were then overdrilled with a 4.5 mm drill bit. This information is relevant to the selection of a replacement screw if a 4.5 mm cortical screw is stripped during orthopaedic surgery. In vitro pullout tests were performed in two independent cadaver studies, each consisting of 12 foal MCIII bones. Two 4.5 mm cortical screws were placed either in the mid-diaphysis (study 1) or distal metaphysis (study 2) of MCIII bones. The holes were then overdrilled with a 4.5 mm bit and had either a 5.5 mm cortical or a 6.5 mm cancellous screw inserted; screw pullout tests were performed at a rate of 0.04 mm/s until screw or bone failure occurred.The bone failed in all of the tests in the diaphyseal and metaphyseal bone. The holding power for 6.5 mm cancellous screws was significantly (p <0.05) greater than for 5.5 mm cortical screws in both the diaphysis and metaphysis. There was not any difference in the holding power of screws in either the diaphysis or the metaphysis between proximal and distal screw holes.If a 4.5 mm cortical bone screw strips in MCIII diaphyseal or metaphyseal bone of foals, a 6.5 mm cancellous screw would provide greater holding power than a 5.5 mm cortical screw.In order to provide information regarding selection of a replacement screw if a 4.5 mm cortical screw is stripped, the in vitro pullout strength was determined for 5.5 mm cortical and 6.5 mm cancellous screws inserted in third metacarpal diaphyseal and metaphyseal bone of foals in which threaded 4.5 mm cortical bone screw insertion holes had been overdrilled with a 4.5 mm bit. The holding power of the 6.5 mm cancellous screw was significantly greater than the 5.5 mm cortical screw in both the diaphysis and metaphysis of foal third metacarpal bone. Thus, it appears that if a 4.5 mm cortical screw is stripped during orthopaedic surgery in foals, a 6.5 mm cancellous screw would provide superior holding power.

COMPARATIVE BIOMECHANICS: CERVICAL SPINE FACET JOINT VERSUS LATERAL MASS SCREW INSERTION TECHNIQUE

2005 ◽  
Vol 09 (03) ◽  
pp. 113-118
Author(s):  
Boon Horng Kam ◽  
Siaw Meng Chou ◽  
Seang Beng Tan
Keyword(s):  
Cervical Spine ◽  
Facet Joint ◽  
Main Concern ◽  
Lateral Mass ◽  
Pullout Strength ◽  
Insertion Technique ◽  
Pullout Resistance ◽  
Screw Insertion ◽  
System A ◽  
Screw Perforation

This study involves a comparative biomechanics of facet joints (FJ) versus lateral mass (LM) screw insertion technique in the human cadaveric lower cervical spine (C3, C4, C5 and C6). The objective of this study is to understand the promising usage of the facet joint insertion technique and to determine the pullout strength of FJ insertion technique for posterior cervical fixation system. A total of 52 disarticulated human vertebrae (C3–C6) were used in this study. DEXA scan was carried out on all specimens before testing. Cortical screws of 3.5 mm and 4.0 mm were used for both FJ and LM techniques, which were subjected to uniaxial load. From the study made so far, the facet joint technique performed well based on the pullout strength values obtained. Having addressed the main concern on screw perforation of lateral mass technique, this facet joint technique not only demonstrated a significantly higher pullout resistance but it is also a relatively low risk surgical procedure.

Assessment in Screw Fixing Damages of Particleboard Surface: Difference in Screw Head and Self-Drilling Features

2013 ◽  
Vol 748 ◽  
pp. 331-335
Author(s):  
Falah Abu ◽  
Mansur Ahmad
Keyword(s):  
Failure Mode ◽  
Failure Modes ◽  
Housing Development ◽  
Insertion Technique ◽  
Screw Head ◽  
Pilot Hole ◽  
Screw Insertion ◽  
Kitchen Cabinet ◽  
Type Of Failure ◽  
Head Type

Construction of kitchen cabinet in Malaysia has grown in correspond to the increasing number of housing development. However, kitchen cabinet supplier is facing with major problem regarding to the increasing number of failure that occurred at the screw jointing during kitchen cabinet installation. Thus, the objective of the study is to observed the failure or damages during screw fixing on kitchen cabinet. It was observed that the screw head and driving features effect the number of damages and the failure mode type. Screw with pan-head type has the lowest number of damages compared with countersunk head screw. Selecting screw insertion technique is also important in order to reduce number of damages. Insertion technique with pilot-hole pre-drilling managed to reduce number of damages and type of failure modes occurred. With this paper, the kitchen cabinet manufacturer will be able to select the best screw with their preferable insertion technique in order to reduce the number of damages used for kitchen cabinet jointing.

Screw Fixing Fracture and Fatigue Failure on Particleboard Surface Using Different Style of Screw Insertion Technique

2014 ◽  
Vol 607 ◽  
pp. 454-457
Author(s):  
Falah Abu ◽  
Mansur Ahmad
Keyword(s):  
Fatigue Failure ◽  
Insertion Technique ◽  
Pilot Hole ◽  
Screw Insertion ◽  
Fracture Failure ◽  
Kitchen Cabinet

Particleboard jointing during screw fixing activities weakens the furniture, kitchen and household joinery. Screw jointing on the particleboard surface contribute to the particleboard fracture. Fracture on the particleboard surface will promote failure in jointing. This study was done to determine the effect of applying different style of screw insertion technique on fracture and fatigue failure. Three different style of screw insertion technique applied was self-drilling, pilot-hole and pilot-hole with countersunk (P+CSK) insertion technique. From the study, applications of P+CSK screw insertion technique caused highest number of damages. 57% of common chipboard screw samples were damaged when P+CSK screw insertion technique was used. Most fracture failure is the type 6 mode. There is no significance difference in number of damages for self-drilling insertion technique and pilot-hole insertion technique. Therefore, self-drilling insertion technique, which is the insertion technique used by kitchen cabinet installer was preferable due to the ease of handling during screw insertion.

scholarly journals Total arthroplasty of basal thumb joint with Elektra prothesis: an in vitro analysis

2016 ◽  
Vol 41 (9) ◽  
pp. 930-938
Author(s):  
A. Completo ◽  
A. Nascimento ◽  
F. Neto
Keyword(s):  
Cancellous Bone ◽  
Computational Models ◽  
Insertion Technique ◽  
Level Of Evidence ◽  
Total Arthroplasty ◽  
Strain Behaviour ◽  
Bone Strains ◽  
Joint Load ◽  
Vitro Analysis

The reported outcomes of the Elektra thumb carpo-metacarpal joint implant have been very variable. This study evaluates the influence of daily cyclic loads and the type of the screw-fit cup insertion technique in the trapezium, with and without prior threading, on the structural bone behaviour. The study was performed experimentally to predict initial implant stability and cortical bone strains. Computational models were developed to assess the structural cancellous bone behaviour. The use of Elektra implant considerably changed the bone strain behaviour compared with the intact joint. This may be associated with risks of cancellous bone fatigue failure due to overload, particularly in the trapezium. The joint load magnitude has a more important structural role than that of the screw-fit cup insertion technique. Limiting the magnitude of thumb loads after arthroplasty may contribute positively to the longevity of this procedure. Level of evidence: V

scholarly journals Surgical performance when inserting non-locking screws: a systematic review

2020 ◽  
Vol 5 (1) ◽  
pp. 26-36 ◽  
Author(s):  
James W.A. Fletcher ◽  
Lisa Wenzel ◽  
Verena Neumann ◽  
R. Geoff Richards ◽  
Boyko Gueorguiev ◽  
...  
Keyword(s):  
Systematic Review ◽  
Bone Density ◽  
Pullout Strength ◽  
Cancellous Screw ◽  
Insertion Technique ◽  
Surgical Performance ◽  
Screw Insertion ◽  
Locking Screws ◽  
The Relationship

Billions of screws are inserted by surgeons each year, making them the most commonly inserted implant. When using non-locking screws, insertion technique is decided by the surgeon, including how much to tighten each screw. The aims of this study were to assess, through a systematic review, the screw tightness and rate of material stripping produced by surgeons and the effect of different variables related to screw insertion. Twelve studies were included, with 260 surgeons inserting a total of 2793 screws; an average of 11 screws each, although only 1510 screws have been inserted by 145 surgeons where tightness was measured – average tightness was 78±10% for cortical (n = 1079) and 80±6% for cancellous screw insertions (n = 431). An average of 26% of all inserted screws irreparably damaged and stripped screw holes, reducing the construct pullout strength. Furthermore, awareness of bone stripping is very poor, meaning that screws must be considerably overtightened before a surgeon will typically detect it. Variation between individual surgeons’ ability to optimally insert screws was seen, with some surgeons stripping more than 90% of samples and others hardly any. Contradictory findings were seen for the relationship between the tightness achieved and bone density. The optimum tightness for screws remains unknown, thus subjectively chosen screw tightness, which varies greatly, remains without an established target to generate the best possible construct for any given situation. Work is needed to establish these targets, and to develop methods to accurately and repeatably achieve them. Cite this article: EFORT Open Rev 2020;5:26-36. DOI: 10.1302/2058-5241.5.180066

scholarly journals DOES THE USE OF DYNAMIC SURGICAL GUIDANCE ASSIST ACCURATE PEDICLE SCREW PLACEMENT IN PATIENTS WITH OSTEOPOROSIS OR OSTEOPENIA?

2020 ◽  
Vol 19 (3) ◽  
pp. 189-193
Author(s):  
HELTON L A DEFINO ◽  
JOHN WILLIAMS ◽  
GEORGIA-LEA WILLIAMS ◽  
KERI GEORGE ◽  
RANDAL BETZ ◽  
...  
Keyword(s):  
Pedicle Screws ◽  
Pedicle Screw Placement ◽  
Level Of Evidence ◽  
Radiation Level ◽  
Intraoperative Radiation ◽  
Surgical Guidance ◽  
Pilot Hole ◽  
Surgical Guide ◽  
Pedicular Screw ◽  
Pedicle Wall

ABSTRACT Objective To compare the use of a dynamic surgical guide (PediGuard®) and pilot hole preparation, with the use of a probe and the aid of fluoroscopy in osteoporotic or osteopenic patients undergoing pedicular fixation of the thoracic or lumbar spine. Methods One hundred and eight patients were randomized. A pilot hole was prepared with the dynamic surgical guide (PediGuard®), or with a probe with the aid of fluoroscopy. A total of 657 vertebral pedicles (120 thoracic and 180 lumbar) were included in the study. The parameters used for the comparison were: accuracy of the pedicular screw, number of fluoroscopic shots, and change in intraoperative trajectory of the perforation after detecting pedicle wall rupture. Results In the group with use of the dynamic surgical guide, malpositioning of the pedicle screws was observed in 8 (2.6%) patients and intraoperative change of perforation trajectory in 12 (4%) patients, and there were 52 fluoroscopic shots. In the group without use of the dynamic surgical guide (PediGuard®), misplacement of the pedicle screws was observed in 33 (11%) patients and intraoperative change of perforation trajectory in 47 (13.2%) patients, and there were 136 fluoroscopic shots. Conclusion The use of the dynamic surgical guide (PediGuard®) in patients with osteoporosis or osteopenia enabled more accurate placement of pedicular screws, with less change in the intraoperative course of the perforation and less intraoperative radiation. Level of Evidence II; Randomized clinical trial of lesser quality.

scholarly journals The Effect of the Lumbar Pedicle and Pediculo-Corporal Junction Histology on the Pedicle Screw Insertion Technique

2020 ◽  
Vol 8 (B) ◽  
pp. 177-180
Author(s):  
Murat Yilmaz ◽  
Beyza Alkis ◽  
Kemal Yucesoy
Keyword(s):  
Pedicle Screw ◽  
Pedicle Screws ◽  
Preparation Technique ◽  
Insertion Technique ◽  
Pilot Hole ◽  
Screw Insertion ◽  
Clinical Center ◽  
Spinal Segments ◽  
Lumbar Spinal ◽  
Lumbar Pedicle

Background Posterior lumbar pedicle screw instrumentation has gained a wide acceptance in the treatment of the various spinal lesions requiring fusion. Inserting screws into the pedicles take a great deal of skill, as the dense bony parts are not large, and a mistake could push a bone fragment into the spinal nerves, causing pain, loss of mobility and other damage. Aim: To investigate the histological and gross-anatomical properties of the pediculocorporal junction, which can have important clinical implications on the insertion technique of the pedicle screws. Study Design: This study was approved by the University Clinical Center Review Board. Human cadaveric lumbar spinal segments which were fixed with formaldehyde were used in the study. Methods: Twenty pedicles from 10 lumbar spinal segments (L3-L5) were prepared for histological and gross-anatomical investigation. Thin slice cuts were taken from the specimens and examined histologically and macroscopically. Results: There were not any differences in the histological characteristics of the pedicles and the pediculo-corporal junction. Thin compact osseous formation or web like connective tissue formation was not identifiable in the pediculo-corporal junction. Conclusion: All kind of pedicle screws can be attempted to be inserted just after preparation of the insertion point with an awl or just decortication of the entrance point with a rongeur. This can also reduce the pilot hole preparation technique related complications like perforation of the pedicle walls.  

Design and Mechanical Evaluation of Sutureless Implants for the Surgery Treatment of Rotator Cuff Tears

2021 ◽  
Author(s):  
Marcília Valéria Guimarães ◽  
Elton Bonifácio ◽  
Thiago Carmo ◽  
Cleudmar Araújo
Keyword(s):  
Rotator Cuff ◽  
Mechanical Behavior ◽  
Functional Disability ◽  
Statistical Significance ◽  
Testing Machine ◽  
Rotator Cuff Tears ◽  
Suture Anchors ◽  
Pullout Strength ◽  
Rigid Foam ◽  
Pullout Tests

Abstract Rotator cuff (RC) tears cause pain and functional disability of the shoulder. Despite advances in suture anchors, there are still reports about the incidence of surgical-related injuries to RC mainly associated with sutures. The purpose of this study was to design and evaluate the mechanical behavior of sutureless implants to repair RC tears. We hypothesized that the implants present mechanical characteristics suitable for the surgical treatment of RC tears as suture anchors. Three different implants (T1,T2,T3) were designed and fabricated with titanium: T1 has two rods and rectangular head; T2 has two rods with a small opening and enlarged rectangular head and T3 has three rods and a circular head. The implants were fixed in rigid polyurethane foam blocks by a series of blows, and the applied mechanical loads along with the number of blows were quantified. Pullout tests using tapes fixed between the implant head and testing machine grip were conducted until implant failure. The maximum pullout strength and displacement of the implant relative to the rigid foam block were computed. Statistical significance was set at p &lt; 0.05. Owing to its geometric configuration, implant T2 presented the best characteristics related to stability, strength, and ease of insertion. Implant T2 confirms our hypothesis that its mechanical behavior is compatible with that of suture anchors which could lead to the reduction of RC repair failures and simplify the arthroscopic procedure.

scholarly journals Evaluation of metallic brackets adhesion after the use of bleaching gels with and without amorphous calcium phosphate (ACP): in vitro study

2013 ◽  
Vol 18 (3) ◽  
pp. 101-106 ◽  
Author(s):  
Sissy Maria Mendes Machado ◽  
Diego Bruno Pinho do Nascimento ◽  
Robson Costa Silva ◽  
Sandro Cordeiro Loretto ◽  
David Normando
Keyword(s):  
Calcium Phosphate ◽  
Bond Strength ◽  
Amorphous Calcium Phosphate ◽  
Shear Bond Strength ◽  
Mechanical Test ◽  
In Vitro Study ◽  
Control Group ◽  
Test Machine ◽  
Tooth Whitening

OBJECTIVE: To evaluate in vitro the effects of tooth whitening using gel with Amorphous Calcium Phosphate (ACP) on the bond strength of metal brackets. METHODS: Thirty-six bovine incisors were sectioned at the crown-root interface, and the crowns were then placed in PVC cylinders. The specimens were divided into 3 groups (n = 12) according to whitening treatment and type of gel used, as follows: G1 (control) = no whitening; G2 = whitening with gel not containing ACP (Whiteness Perfect - FGM), G3 = whitening with gel containing ACP (Nite White ACP - Discus Dental). Groups G2 and G3 were subjected to 14 cycles of whitening followed by an interval of 15 days before the bonding of metal brackets. Shear bond strength testing was performed on a Kratos universal test machine at a speed of 0.5 mm/min. After the mechanical test, the specimens were assessed to determine the adhesive remnant index (ARI). The results were subjected to ANOVA, Tukey's test and Kruskal-Wallis test (5%). RESULTS: Significant differences were noted between the groups. Control group (G1 = 11.10 MPa) showed a statistically higher shear bond strength than the groups that underwent whitening (G2 = 5.40 Mpa, G3 = 3.73 MPa), which did not differ from each other. There were no significant differences between the groups in terms of ARI. CONCLUSION: Tooth whitening reduces the bond strength of metal brackets, whereas the presence of ACP in the whitening gel has no bearing on the results.

Sign in / Sign up

Export Citation Format

Share Document