Effectiveness of cemented rescue screws for anterior cervical plate fixation

Object Among the various ways to optimize the fixation of bone implants is to use bone cement, for example, in a total hip prosthesis. No data exist, however, concerning the effectiveness of cemented rescue screws for anterior cervical plate fixation. The aim of this study was to investigate whether cemented rescue screws increase fixation strength in comparison with uncemented standard screws. Methods Six cervical spine segments (C4–7) were explanted during routine autopsy studies from fresh human cadavers. Bone mineral density (BMD) was measured for each vertebral body (VB) using quantitative computerized tomography scanning, and 24 VBs were dissected from the segments. Two initial pilot holes were drilled into each VB parallel to the sagittal plane. Based on their BMD, the specimens were assigned to one of two groups in which torque and pullout force were tested. The test was begun with standard screws and was repeated with cannulated slotted rescue screws into which bone cement was injected. The mean values of peak torque and pullout forces resulting from the left and right measurements were used for statistical analysis. A t-test was performed to determine the effect of screw type on peak torque and pullout force. Moment correlation coefficients were calculated to determine the effect of BMD on peak torque and pullout force for each type of screw. The mean insertional peak torque was 67.1 N/cm for the standard screw and 102.6 N/cm for the cemented screw (p < 0.05). The mean pullout force was 526.9 N for standard osteoporosis screws and 531.5 N for cemented screws (p > 0.05). The effect of increased holding strength as measured by peak torque and pullout force was more pronounced in the presence of low bone density. Conclusions Cemented rescue screws that have been inserted into a fatigued pilot hole in the cervical VB strengthen the screw–bone interface compared with the strength initially conferred by a standard screw.

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Anterior Cervical Plate Fixation: A Biomechanical Study to Evaluate the Effects of Plate Design, Endplate Preparation, and Bone Mineral Density

Spine ◽

10.1097/01.brs.0000152154.57171.92 ◽

2005 ◽

Vol 30 (3) ◽

pp. 294-301 ◽

Cited By ~ 56

Author(s):

Marcel F. Dvorak ◽

Tobias Pitzen ◽

Qingan Zhu ◽

Jeff D. Gordon ◽

Charles G. Fisher ◽

...

Keyword(s):

Bone Mineral Density ◽

Bone Mineral ◽

Plate Fixation ◽

Biomechanical Study ◽

Mineral Density ◽

Plate Design ◽

Cervical Plate ◽

Anterior Cervical Plate

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Insertion torque and pullout force of rescue screws for anterior cervical plate fixation in a fatigued initial pilot hole

Journal of Neurosurgery Spine ◽

10.3171/spi.2004.1.2.0198 ◽

2004 ◽

Vol 1 (2) ◽

pp. 198-201 ◽

Cited By ~ 18

Author(s):

Tobias Pitzen ◽

Frederick Franta ◽

Dragos Barbier ◽

Wolf-Ingo Steudel

Keyword(s):

Strong Correlation ◽

Peak Torque ◽

Insertion Torque ◽

Mineral Density ◽

Content Type ◽

Pullout Force ◽

Pilot Hole ◽

The Mean ◽

Rescue Screw ◽

Fine Print

Object. The purpose of this study was to investigate whether thicker-core-diameter screws increase fixation strength in the cervical spine. Methods. Bone mineral density (BMD) was determined for each vertebral body (VB) obtained in six human C4–7 segments. Based on their BMD, the specimens were assigned to one of two groups in which torque and pullout force were tested. Two initial pilot holes were drilled into the VBs and tests were first performed using a standard screw. The test was repeated using a thicker rescue screw inserted into the same initial pilot hole. The mean value of peak torque and pullout force resulting from the single left/right measurements was used for statistical analysis. A t-test was performed to determine the effect of screw design on peak torque and pullout force. Moment correlation coefficients were calculated to determine the effect of BMD on peak torque and pullout force. Mean insertional peak torque for the standard screw was 82.1 N/cm and that for the rescue screw was 47.6 Ncm (p < 0.001). There was a strong correlation between insertional peak torque and BMD for both standard screws (r = 0.71, p = 0.02) and rescue screws (r = 0.59, p = 0.07). The mean pullout force for standard screws was 464.7 N, whereas it was 164.5 N for rescue screws (p < 0.001). There was a strong correlation between pullout force and BMD for both standard (r = 0.75, p = 0.0081) and rescue screws (r = 0.7, p = 0.025). Conclusions. Uncemented rescue screws that have been inserted into a fatigued hole in the cervical VB do not strengthen the screw—bone interface compared with the strength initially conferred by a standard screw.

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Does smoking have an impact on fusion rate in single-level anterior cervical discectomy and fusion with allograft and rigid plate fixation?

Journal of Neurosurgery Spine ◽

10.3171/2013.7.spine13208 ◽

2013 ◽

Vol 19 (5) ◽

pp. 527-531 ◽

Cited By ~ 23

Author(s):

Myles Luszczyk ◽

Justin S. Smith ◽

Jeffrey S. Fischgrund ◽

Steven C. Ludwig ◽

Rick C. Sasso ◽

...

Keyword(s):

Plate Fixation ◽

Fusion Rate ◽

Anterior Cervical Discectomy ◽

Cervical Disc ◽

Cervical Discectomy ◽

Single Level ◽

Significant Difference ◽

Solid Fusion ◽

Cervical Plate ◽

Anterior Cervical Plate

Object Although smoking has been shown to negatively affect fusion rates in patients undergoing multilevel fusions of the cervical and lumbar spine, the effect of smoking on fusion rates in patients undergoing single-level anterior cervical discectomy and fusion (ACDF) with allograft and plate fixation has yet to be thoroughly investigated. The objective of the present study was to address the effect of smoking on fusion rates in patients undergoing a 1-level ACDF with allograft and a locked anterior cervical plate. Methods This study is composed of patients from the control groups of 5 separate studies evaluating the use of an anterior cervical disc replacement to treat cervical radiculopathy. For each of the 5 studies the control group consisted of patients who underwent a 1-level ACDF with allograft and a locked cervical plate. The authors of the present study reviewed data obtained in a total of 573 patients; 156 patients were smokers and 417 were nonsmokers. A minimum follow-up period of 24 months was required for inclusion in this study. Fusion status was assessed by independent observers using lateral, neutral, and flexion/extension radiographs. Results An overall fusion rate of 91.4% was achieved in all 573 patients. A solid fusion was shown in 382 patients (91.6%) who were nonsmokers. Among patients who were smokers, 142 (91.0%) had radiographic evidence of a solid fusion. A 2-tailed Fisher exact test revealed a p value of 0.867, indicating no difference in the union rates between smokers and nonsmokers. Conclusions The authors found no statistically significant difference in fusion status between smokers and nonsmokers who underwent a single-level ACDF with allograft and a locked anterior cervical plate. Although the authors do not promote tobacco use, it appears that the use of allograft with a locked cervical plate in single-level ACDF among smokers produces similar fusion rates as it does in their nonsmoking counterparts.

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Early Failure of Long Segment Anterior Cervical Plate Fixation

Journal of Spinal Disorders ◽

10.1097/00002517-199810000-00008 ◽

1998 ◽

Vol 11 (5) ◽

pp. 410???415 ◽

Cited By ~ 128

Author(s):

Alexander R. Vaccaro ◽

Stephen P. Falatyn ◽

Gaetano J. Scuderi ◽

Frank J. Eismont ◽

Robert A. McGuire ◽

...

Keyword(s):

Plate Fixation ◽

Early Failure ◽

Cervical Plate ◽

Anterior Cervical Plate

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A Case of Hypopharyngeal Perforation after Anterior Cervical Plate Fixation

Practica Oto-Rhino-Laryngologica ◽

10.5631/jibirin.111.415 ◽

2018 ◽

Vol 111 (6) ◽

pp. 415-419

Author(s):

Kouhei Mihashi ◽

Eiji Takeuchi ◽

Kazunori Fujiwara ◽

Hiromi Takeuchi

Keyword(s):

Plate Fixation ◽

Hypopharyngeal Perforation ◽

Cervical Plate ◽

Anterior Cervical Plate

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Plate fixation in the cervical spine: traditional paramedian screw configuration compared with unique unilateral configuration

Journal of Neurosurgery Spine ◽

10.3171/2013.3.spine12949 ◽

2013 ◽

Vol 18 (6) ◽

pp. 575-581 ◽

Cited By ~ 3

Author(s):

Prasath Mageswaran ◽

Robert F. McLain ◽

Robb Colbrunn ◽

Tara Bonner ◽

Elijah Hothem ◽

...

Keyword(s):

Repeated Measures ◽

Plate Fixation ◽

Axial Rotation ◽

Torsional Stiffness ◽

Fixation Strength ◽

Rigid Fixation ◽

Lateral Bending ◽

Flexion Extension ◽

Standard Plate ◽

Cervical Plate

Object This study compared the fixing strength and stability achieved by a unilateral plate and screw configuration against a standard cervical fixation plate using a single-level corpectomy and allograft strut graft model. Methods Multidirectional in vitro flexibility tests were performed using a robotic spine testing system. Human cadaveric spines were assessed for spinal stability after vertebral corpectomy and anterior instrumentation. Specimens were mounted cranially and caudally on custom jigs that were then attached to load cells on the robotic system's end effector and base pedestal. C2–T1 spine specimens (n = 6) were tested intact; then after C-5 corpectomy (the vertebral body was excised), allograft placement and anterior plate fixation were performed. The surgeons performed a uniform corpectomy and reconstruction of each specimen in a protocol fashion. Two plates were compared: a unilateral 4-hole cervical plate designed to obtain rigid fixation using 4 convergent fixation screws all placed unilateral to the vertebral midline, and a standard cervical plate with bilateral plate screw configuration. The plate testing sequence was selected at random to limit bias. Fixation screws were matched for length and diameter. Pure moments were applied under load control (maximum 1.8 Nm) in flexion, extension, left/right lateral bending, and left/right axial rotation. Vertebral motion was measured using an optoelectronic system. The mean relative range of motion between C-4 and C-6 was compared among groups using repeated-measures ANOVA (significance level of 0.05). Results In comparing the intact construct and 2 different plates in all planes of motion, only motion in extension (intact vs unilateral plate, p = 0.003; intact vs standard plate, p = 0.001) and left axial rotation (intact vs unilateral plate, p = 0.019) were significantly affected. In terms of immediate cervical stability after 1-level corpectomy and placement of an allograft reconstruction, the unilateral plate showed comparable stiffness to the standard plate in all 3 motion planes (flexion [p = 0.993], extension [p = 0.732], left lateral bending [p = 0.683], right lateral bending [p = 0.546], left axial rotation [p = 0.082], and right axial rotation [p = 0.489]). The unilateral plate showed a trend toward improved stiffness in axial rotation. In no direction did the unilateral configuration prove significantly less stiff than the traditional configuration. Conclusions The unilateral plate design proposed here requires minimal dissection and retraction beyond the midline of tissues susceptible to scar, postoperative pain, and swelling. The authors' study suggests that a unilateral plate can be configured to provide comparable fixation strength and torsional stiffness compared with traditional, widely accepted plate designs.

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The Choice of the Best Surgery After Single Level Anterior Cervical Spine Discectomy: A Systematic Review

The Open Orthopaedics Journal ◽

10.2174/1874325001206010121 ◽

2012 ◽

Vol 6 (1) ◽

pp. 121-128 ◽

Cited By ~ 7

Author(s):

Ricardo Vieira Botelho ◽

Yuri dos Santos Buscariolli ◽

Marcus Vinicius Flores de Barros Vasconcelos Fernandes Serra ◽

Marcia Nogueira Pires Bellini ◽

Wanderley Marques Bernardo

Keyword(s):

Randomized Trials ◽

Plate Fixation ◽

Clinical Results ◽

Limited Evidence ◽

Moderate Evidence ◽

Intervertebral Disc Height ◽

Central Registry ◽

Cervical Plate ◽

Intervertebral Cage ◽

Anterior Cervical Plate

Background: The anterior cervical discectomy (ACD) is often used to treat spinal cord and nerve root compressions and the frequent use of interbody fusion (ACDF) has popularized it as a common practice associated or not with cages or plates for maintaining the intervertebral disc height. Objective: The aim of this study is to clarify the effectiveness of ACD compared with ACDF, with or without the use of anterior cervical spacer (Cage) or instrumentation with plate fixation (ACDFI). Methods: randomized controlled trials or quasi-randomized trials were selected for analysis in one segmental level. The comparison criteria were the rates of success and failure with surgery (Odom’s’ criteria), fusion rates and kyphosis rates. Electronic search was made in the MEDLINE database (Pubmed), in the Central Registry of randomized trials of Cochrane database and EMBASE. Results: Seven studies were selected for analysis. Conclusion: Implications for practice: There is moderate evidence that clinical results of ACD and ACDF are not significant different. There is moderate evidence that addition of intervertebral cage enhance clinical results.There is moderate evidence that anterior cervical plate does not change the clinical results of ACD. There is moderate evidence that ACD produce more segmental kyphosis than ACDF and ACDFI, with use of cage or plate.There is moderate evidence that ACD produce lower rate of fusion than ACDF and than the cages. There is limited evidence of the lower capacity of PMMA to produce fusion. There is limited evidence that fused patients have better outcome than non fused patients.

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