keyword
MENU ▼
Read by QxMD icon Read
search

Pedicle screw torque

keyword
https://www.readbyqxmd.com/read/29734349/bioactive-pedicle-screws-prepared-by-chemical-and-heat-treatments-improved-biocompatibility-and-bone-bonding-ability-in-canine-lumbar-spines
#1
Koji Akeda, Seiji Yamaguchi, Tomiharu Matsushita, Tadashi Kokubo, Koichiro Murata, Norihiko Takegami, Akihiko Matsumine, Akihiro Sudo
BACKGROUND: Titanium (Ti)-6Al-4V alloy, which is widely used in spinal instrumentation with a pedicle screw (PS) system. However, significant clinical problems, including loosening and back-out of PSs, persist. During the last decade, a novel technology that produces bioactive Ti from chemical and heat treatments has been reported that induces the spontaneous formation of a hydroxyapatite (HA) layer on the surface of Ti materials. The purpose of this study was to study the effect of bioactivation of Ti-6Al-4V PSs on the ability of HA formation in vitro and its biocompatibility and bone-bonding ability in vivo...
2018: PloS One
https://www.readbyqxmd.com/read/29600908/pedicle-screws-with-a-thin-hydroxyapatite-coating-for-improving-fixation-at-the-bone-implant-interface-in-the-osteoporotic-spine-experimental-study-in-a-porcine-model
#2
Makoto Ohe, Hiroshi Moridaira, Satoshi Inami, Daisaku Takeuchi, Yutaka Nohara, Hiroshi Taneichi
OBJECTIVE Instrumentation failure caused by the loosening of pedicle screws (PSs) in patients with osteoporosis is a serious problem after spinal surgery. The addition of a thin hydroxyapatite (HA) surface coating applied by using a sputtering process was reported recently to be a promising method for providing bone conduction around an implant without a significant risk of coating-layer breakage. In this study, the authors evaluated the biomechanical and histological features of the bone-implant interface (BII) of PSs with a thin HA coating in an in vivo porcine osteoporotic spine model...
March 30, 2018: Journal of Neurosurgery. Spine
https://www.readbyqxmd.com/read/29260301/regional-hounsfield-unit-measurement-of-screw-trajectory-for-predicting-pedicle-screw-fixation-using-cortical-bone-trajectory-a-retrospective-cohort-study
#3
Keitaro Matsukawa, Yuichiro Abe, Yoshihide Yanai, Yoshiyuki Yato
BACKGROUND: The sufficiency of screw anchoring is a critical factor for achieving successful spinal fusion; however, no reliable method for predicting pedicle screw fixation has been established. Recently, Hounsfield units (HU) obtained from computed tomography (CT) was developed as a new reliable tool to determine the bone quality. The purpose of the present study was to demonstrate the utility of regional HU measurement of the screw trajectory to predict the primary and long-term fixation strength of pedicle screws...
February 2018: Acta Neurochirurgica
https://www.readbyqxmd.com/read/29149204/evaluation-of-osseous-integration-of-titanium-orthopedic-screws-with-novel-sla-treatment-in-porcine-model
#4
Tzu-Hsiang Lin, Hsin-Tai Hu, Hsueh-Chun Wang, Meng-Chian Wu, Shu-Wei Wu, Ming-Long Yeh
The success of many endosseous implants in orthopaedic and dental applications depends on the surface characteristics, as they affect osseous integration. Previous investigations indicated that a novel large-grit sand-blasted and acid-etched (SLA) titanium (denoted as SLAffinity-Ti) implant had better bone integration than that of a comparably shaped implant with a plasma-sprayed titanium surface. The purpose of the present investigation was to create a SLAffinity surface on pedicle screws and trauma screws and to compare it with the surfaces of a sand-blasted-only implant and commercial implants in terms of bone integration...
2017: PloS One
https://www.readbyqxmd.com/read/29059807/novel-synthetic-vertebrae-provide-realistic-haptics-for-pedicle-screw-placement
#5
Marianne Hollensteiner, Peter Augat, David Furst, Benjamin Esterer, Stefan Gabauer, Klaus Puschel, Falk Schrodl, Andreas Schrempf
During vertebral surgery, misplaced pedicle screws can harm vital neural and vascular structures. Haptic distinction between cortical and cancellous bone structures is therefore essential for correct screw placement. This tactile experience during pedicle screw placement can be obtained by training on human or animal specimens even if expensive or ethically questionable. In this study, novel synthetic vertebrae were evaluated within a hybrid simulator to provide realistic haptics for the training of spine surgeries...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28968476/effect-of-pedicle-fill-on-axial-pullout-strength-in-spinal-fixation-after-rod-reduction
#6
Kevin Albanese, Nathaniel R Ordway, Stephen A Albanese, William F Lavelle
Rod reduction to pedicle screws is used for a variety of spinal fixation procedures; however, it can alter the integrity of the screw-bone interface. The authors investigated the effect of pedicle fill (ratio of pedicle screw diameter to pedicle diameter) on the strength of the screw-bone interface after simulated rod reduction on 17 vertebrae (3 thoracolumbar spine specimens). Pedicle diameter was measured with standard clinical computed tomography scan protocols. The authors determined the minimum pedicle diameter for each level...
October 2, 2017: Orthopedics
https://www.readbyqxmd.com/read/28754114/the-effect-of-different-screw-rod-design-on-the-anti-rotational-torque-a-biomechanical-comparison-of-three-conventional-screw-rod-constructs
#7
Zifang Huang, Chongwen Wang, Hengwei Fan, Wenyuan Sui, Xueshi Li, Qifei Wang, Junlin Yang
BACKGROUND: Screw-rod constructs have been widely used to correct spinal deformities, but the effects of different screw-rod systems on anti-rotational torque have not been determined. This study aimed to analyze the biomechanical effect of different rod-screw constructs on anti-rotational torque. METHODS: Three conventional spinal screw-rod systems (Legacy, RF-F-10 and USSII) were used to test the anti-rotational torque in the material test machine. ANOVA was performed to evaluate the anti-rotational capacity of different pedicle screws-rod constructs...
July 28, 2017: BMC Musculoskeletal Disorders
https://www.readbyqxmd.com/read/28752245/which-salvage-fixation-technique-is-best-for-the-failed-initial-screw-fixation-at-the-cervicothoracic-junction-a-biomechanical-comparison-study
#8
Jae Taek Hong, Takigawa Tomoyuki, Ashish Jain, Alejandro A Espinoza Orías, Nozomu Inoue, Howard S An
PURPOSE: The pedicle screw construct is the most widely used technique for instrumentation at cervicothoracic junction (CTJ) because of its high biomechanical stability. However, we may need salvage fixation options for it as there might be a situation when pedicle screw is not available or it initially fails in order to obviate the need to instrument an additional motion segment. We aimed to evaluate the ability of using salvage screw fixations at CTJ (C7, T1, T2), when the initial fixation method fails...
July 27, 2017: European Spine Journal
https://www.readbyqxmd.com/read/28547867/pull-out-strength-of-dual-outer-diameter-pedicle-screws-compared-to-uncemented-and-cemented-standard-pedicle-screws-a-biomechanical-in-vitro-study
#9
Andrea Lorenz, Carmen I Leichtle, Sandra Frantz, Marte Bumann, Ilias Tsiflikas, Thomas Shiozawa, Ulf G Leichtle
OBJECTIVE: To analyze the potential of the dual outer diameter screw and systematically evaluate the pull-out force of the dual outer diameter screw compared to the uncemented and cemented standard pedicle screws with special regard to the pedicle diameter and the vertebra level. METHODS: Sixty vertebrae of five human spines (T 6 -L 5 ) were sorted into three study groups for pairwise comparison of the uncemented dual outer diameter screw, the uncemented standard screw, and the cemented standard screw, and randomized with respect to bone mineral density (BMD) and vertebra level...
May 2017: Orthopaedic Surgery
https://www.readbyqxmd.com/read/28525468/cortical-bone-trajectory-for-thoracic-pedicle-screws-a-technical-note
#10
Keitaro Matsukawa, Yoshiyuki Yato, Richard A Hynes, Hideaki Imabayashi, Naobumi Hosogane, Takashi Asazuma, Toshiyasu Matsui, Yasushi Kobayashi, Koichi Nemoto
STUDY DESIGN: A morphometric measurement of new thoracic pedicle screw trajectory using computed tomography and a biomechanical study on cadaveric thoracic vertebrae using insertional torque. OBJECTIVE: To introduce a new thoracic pedicle screw trajectory which maximizes engagement with denser bone. SUMMARY OF BACKGROUND DATA: Cortical bone trajectory (CBT) which maximizes the thread contact with cortical bone provides enhanced screw purchase...
June 2017: Clinical Spine Surgery
https://www.readbyqxmd.com/read/28437331/do-the-position-and-orientation-of-the-crosslink-influence-the-stiffness-of-spinal-instrumentation
#11
Zhuo Wang, Toshihiko Sakakibara, Takamasa Yoshikawa, Tadashi Inaba, Yuichi Kasai
STUDY DESIGN: Biomechanical study of double-level pedicle screw constructs with or without crosslinks (CL) in an unstable model. OBJECTIVES: The purpose of this study is to investigate the optimal position and orientation of the CL. SUMMARY OF BACKGROUND DATA: Several reports have described biomechanical research on such CL, but no definite consensus has been reached regarding the effects. Very few studies have examined the position and orientation of the CL...
May 2017: Clinical Spine Surgery
https://www.readbyqxmd.com/read/28414169/a-biomechanical-investigation-of-different-screw-head-designs-for-vertebral-derotation-in-scoliosis-surgery
#12
Po-Yi Liu, Po-Liang Lai, Chun-Li Lin
BACKGROUND CONTEXT: The posterior pedicle screw-rod system, which is widely used to correct spinal deformities, achieves a good correction rate in the frontal and coronal planes but not in the axial plane. Direct vertebral derotation (DVD) was developed to correct axial plane deformities. However, the design of screw head and body connection, in terms of monoaxial, polyaxial, and uniplanar screw, may influence the efficiency of DVD. PURPOSE: This study compared the efficiency of a newly designed uniplanar screw with that of monoaxial and polyaxial screws in the DVD maneuver...
April 13, 2017: Spine Journal: Official Journal of the North American Spine Society
https://www.readbyqxmd.com/read/28387967/intraoperative-biomechanics-of-lumbar-pedicle-screw-loosening-following-successful-arthrodesis
#13
Hope B Pearson, Christopher J Dobbs, Eric Grantham, Glen L Niebur, James L Chappuis, Joel D Boerckel
Pedicle screw loosening has been implicated in recurrent back pain after lumbar spinal fusion, but the degree of loosening has not been systematically quantified in patients. Instrumentation removal is an option for patients with successful arthrodesis, but remains controversial. Here, we quantified pedicle screw loosening by measuring screw insertion and/or removal torque at high statistical power (beta = 0.02) in N = 108 patients who experienced pain recurrence despite successful fusion after posterior instrumented lumbar fusion with anterior lumbar interbody fusion (L2-S1)...
December 2017: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/27939099/effect-of-various-factors-on-pull-out-strength-of-pedicle-screw-in-normal-and-osteoporotic-cancellous-bone-models
#14
Vicky Varghese, Gurunathan Saravana Kumar, Venkatesh Krishnan
Pedicle screws are widely used for the treatment of spinal instability by spine fusion. Screw loosening is a major problem of spine fusion, contributing to delayed patient recovery. The present study aimed to understand the factor and interaction effects of density, insertion depth and insertion angle on pedicle screw pull out strength and insertion torque. A pull out study was carried out on rigid polyurethane foam blocks representing osteoporotic to normal bone densities according to the ASTM-1839 standard...
February 2017: Medical Engineering & Physics
https://www.readbyqxmd.com/read/27927550/strength-of-thoracic-spine-under-simulated-direct-vertebral-rotation-a-biomechanical-study
#15
Sean L Borkowski, Sophia N Sangiorgio, Richard E Bowen, Anthony A Scaduto, Bo He, Kathryn L Bauer, Edward Ebramzadeh
BACKGROUND: Direct vertebral rotation (DVR) has gained increasing popularity for deformity correction surgery. Despite large moments applied intraoperatively during deformity correction and failure reports including screw plow, aortic abutment, and pedicle fracture, to our knowledge, the strength of thoracic spines has been unknown. Moreover, the rotational response of thoracic spines under such large torques has been unknown. PURPOSE: Simulate DVR surgical conditions to measure torsion to failure on thoracic spines and assess surgical forces...
March 2016: Spine Deformity
https://www.readbyqxmd.com/read/27852493/biomechanical-comparison-of-spinopelvic-fixation-constructs-iliac-screw-versus-s2-alar-iliac-screw
#16
Camden B Burns, Karan Dua, Nicholas A Trasolini, David E Komatsu, James M Barsi
STUDY DESIGN: Biomechanical cadaveric study. OBJECTIVE: To compare the biomechanical properties of the iliac and S2-Alar-Iliac (S2AI) screw in a similar spinopelvic fixation construct. SUMMARY OF BACKGROUND DATA: Spinopelvic fixation is used in the correction of pelvic obliquity, high-grade spondylolisthesis, and long spinal fusions. With the development of pedicle screw fixation, the iliac screw has been used as an anchor point to the pelvis...
January 2016: Spine Deformity
https://www.readbyqxmd.com/read/27678328/pull-out-strength-of-cemented-solid-versus-fenestrated-pedicle-screws-in-osteoporotic-vertebrae
#17
C I Leichtle, A Lorenz, S Rothstock, J Happel, F Walter, T Shiozawa, U G Leichtle
OBJECTIVES: Cement augmentation of pedicle screws could be used to improve screw stability, especially in osteoporotic vertebrae. However, little is known concerning the influence of different screw types and amount of cement applied. Therefore, the aim of this biomechanical in vitro study was to evaluate the effect of cement augmentation on the screw pull-out force in osteoporotic vertebrae, comparing different pedicle screws (solid and fenestrated) and cement volumes (0 mL, 1 mL or 3 mL)...
September 2016: Bone & Joint Research
https://www.readbyqxmd.com/read/27391398/biomechanical-evaluation-of-lateral-lumbar-interbody-fusion-with-secondary-augmentation
#18
Marco T Reis, Phillip M Reyes, Bse, Idris Altun, Anna G U S Newcomb, Vaneet Singh, Steve W Chang, Brian P Kelly, Neil R Crawford
OBJECTIVE Lateral lumbar interbody fusion (LLIF) has emerged as a popular method for lumbar fusion. In this study the authors aimed to quantify the biomechanical stability of an interbody implant inserted using the LLIF approach with and without various supplemental fixation methods, including an interspinous plate (IP). METHODS Seven human cadaveric L2-5 specimens were tested intact and in 6 instrumented conditions. The interbody implant was intended to be used with supplemental fixation. In this study, however, the interbody was also tested without supplemental fixation for a relative comparison of these conditions...
December 2016: Journal of Neurosurgery. Spine
https://www.readbyqxmd.com/read/27352365/influence-of-hydroxyapatite-stick-on-pedicle-screw-fixation-in-degenerative-lumbar-spine-biomechanical-and-radiologic-study
#19
Sung Joon Shin, Ji-Ho Lee, Jae Hyup Lee
STUDY DESIGN: A prospective, within-patient, left-right comparative study. OBJECTIVE: To evaluate the efficacy of hydroxyapatite (HA) stick augmentation method by comparing the insertional torque of the pedicle screw in osteoporotic and nonosteoporotic patients. SUMMARY OF BACKGROUND DATA: Unsatisfactory clinical outcomes after spine surgery in osteoporotic patients are related to pedicle screw loosening or pull-outs. HA, as a bone graft extender, has a possibility to enhance the fixation strength at the bone-screw interface...
July 2017: Clinical Spine Surgery
https://www.readbyqxmd.com/read/27326962/cortical-bone-trajectory-for-thoracic-pedicle-screws-a-technical-note
#20
Keitaro Matsukawa, Yoshiyuki Yato, Richard A Hynes, Hideaki Imabayashi, Naobumi Hosogane, Takashi Asazuma, Matsui Toshiyasu, Yasushi Kobayashi, Koichi Nemoto
STUDY DESIGN: A morphometric measurement of new thoracic pedicle screw trajectory using computed tomography (CT) and a biomechanical study on cadaveric thoracic vertebrae using insertional torque. OBJECTIVE: To introduce a new thoracic pedicle screw trajectory which maximizes engagement with denser bone. SUMMARY OF BACKGROUND DATA: Cortical bone trajectory (CBT) which maximizes the thread contact with cortical bone provides enhanced screw purchase...
June 20, 2016: Clinical Spine Surgery
keyword
keyword
97559
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"