Anterior Plate-Screws and Lower Postoperative T1 Slope Affect Cervical Allospacer Failures in Multi-Level ACDF Surgery: Anterior Versus Posterior Fixation

Study Design: Prospective observational study. Objective: In ACDF, graft failure and subsidence are common complications of surgery. Depending on the cervical fixation, different biomechanical characteristics are applied on the grafts. This aims to describe the incidence of cervical spacer failure in patients with cervical degenerative condition according to the cervical fixation method and sagittal balance. Method: From November 2011 to December 2015, 262 patients who underwent cervical spine surgery were enrolled prospectively. Patients were divided into 3 groups based on fixation method: anterior plate/screw (APS), posterior lateral mass screw (LMS), pedicle screw (PPS) groups. Serial X-rays and CT scans were utilized to evaluate radiologic outcomes. Results: Mean patient ages were 56.1 years in the APS group, 61.5 years in the LMS group, and 57.6 years in the PPS group ( P = 0.002). Allospacer failure was most common in the APS group, compared to the LMS and PPS groups (chi-square, P = 0.038). Longer fusion level was associated with greater allospacer failure (Baseline 2 level surgery; Odds ratio (OR) 3.4 in 3 level, 15.2 in 4 level, P = 0.036,0.013). Higher T1 slope was correlated with less allospacer failure (OR 0.875, P = 0.001). ORs of allospacer failure in the LMS and PPS groups were 0.04 and 0.02, respectively, ( P = 0.01, 0.01), compared with the APS group. Conclusion: This study was able to show that allospacer failure in multi-level ACDF surgery is more common with a longer fusion length, less postoperative T1 slope, and an anterior plate-screws technique. Pedicle screws provided the best biomechanical stability among the 3 constructs.

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Construct Stability of C2 Replacement Strategies

Advances in Bioengineering ◽

10.1115/imece2003-42893 ◽

2003 ◽

Author(s):

Christian M. Puttlitz ◽

Robert P. Melcher ◽

Vedat Deviren ◽

Dezsoe Jeszenszky ◽

Ju¨rgen Harms

Keyword(s):

Repeated Measures ◽

Posterior Instrumentation ◽

Statistical Significance ◽

Axial Rotation ◽

Posterior Fixation ◽

Camera Motion ◽

Anterior Plate ◽

Intact Specimen ◽

Strut Graft ◽

Significant Difference

Reconstruction of C2 after tumor destruction and resection remains a significant challenge. Most constructs utilize a strutgraft with plate or screw fixation. A novel C2 prosthesis combining a titanium mesh cage with bilateral C1 shelves and a T-plate has been used successfully in 18 patients. Supplemental posterior instrumentation includes C0-C3 or C1-C3. Biomechanical comparisons of this C2 prosthesis with traditional fixation options have not been reported. Five fresh-frozen human cadaveric cervical spines (C0-C5) were tested intact. Next, the C2 prosthesis, and strut graft and anterior plate constructs were tested with occiput-C3 and C1-C3 posterior fixation. Pure moment loads (up to 1.5 N-m) were applied in flexion and extension, lateral bending, and axial rotation. C1-C3 motion was evaluated using 3 camera motion analysis. Statistical significance was evaluated using one-way repeated measures ANOVA with Student-Newman-Keuls post hoc pairwise comparisons. All constructs provided a statistically significant decrease in motion in this C2 corpectomy model as compared to the intact condition. There was no significant difference in C1-C3 motion between the 4 constructs, regardless of whether the occiput was included in the fixation. Under these loading conditions, both the C2 prostheisis and strut-graft-plate constructs provided initial C1-C3 stability beyond that of the intact specimen. The occiput does not need to be included in the posterior instrumentation.

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Transfacet screw placement for posterior fixation of C-7

Journal of Neurosurgery Spine ◽

10.3171/spi/2008/9/8/200 ◽

2008 ◽

Vol 9 (2) ◽

pp. 200-206 ◽

Cited By ~ 17

Author(s):

Eric M. Horn ◽

Nicholas Theodore ◽

Neil R. Crawford ◽

Nicholas C. Bambakidis ◽

Volker K. H. Sonntag

Keyword(s):

Intraoperative Complications ◽

Pedicle Screws ◽

Retrospective Chart Review ◽

Screw Placement ◽

Posterior Fixation ◽

Lateral Mass ◽

Screw Insertion ◽

Novel Technique ◽

Hardware Failures

Object Lateral mass screws are traditionally used to fixate the subaxial cervical spine, while pedicle screws are used in the thoracic spine. Lateral mass fixation at C-7 is challenging due to thin facets, and placing pedicle screws is difficult due to the narrow pedicles. The authors describe their clinical experience with a novel technique for transfacet screw placement for fixation at C-7. Methods A retrospective chart review was undertaken in all patients who underwent transfacet screw placement at C-7. The technique of screw insertion was the same for each patient. Polyaxial screws between 8- and 10-mm-long were used in each case and placed through the facet from a perpendicular orientation. Postoperative radiography and clinical follow-up were analyzed for aberrant screw placement or construct failure. Results Ten patients underwent C-7 transfacet screw placement between June 2006 and March 2007. In all but 1 patient screws were placed bilaterally, and the construct lengths ranged from C-3 to T-5. One patient with a unilateral screw had a prior facet fracture that precluded bilateral screw placement. There were no intraoperative complications or screw failures in these patients. After an average of 6 months of follow-up there were no hardware failures, and all patients showed excellent alignment. Conclusions The authors present the first clinical demonstration of a novel technique of posterior transfacet screw placement at C-7. These results provide evidence that this technique is safe to perform and adds stability to cervicothoracic fixation.

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Surgical Management and Outcome of Tuberculous Atlantoaxial Dislocation: A 15-year Experience

Neurosurgery ◽

10.1227/01.neu.0000043930.28934.fe ◽

2003 ◽

Vol 52 (2) ◽

pp. 331-339 ◽

Cited By ~ 48

Author(s):

Sanjiv Sinha ◽

Anil Kumar Singh ◽

Vikas Gupta ◽

Daljit Singh ◽

Masakazu Takayasu ◽

...

Keyword(s):

Early Mobilization ◽

Craniovertebral Junction ◽

Magnetic Resonance Images ◽

Atlantoaxial Dislocation ◽

Direct Access ◽

Posterior Fixation ◽

Radical Excision ◽

Histopathological Analysis ◽

X Rays ◽

Delay In Diagnosis

Abstract OBJECTIVE Tuberculous atlantoaxial dislocation is a rare disease entity. However, tuberculosis continues to be endemic in developing countries. Its earliest clinical presentation may be nonspecific, and delay in diagnosis may lead to irreversible neurological deficit. The management of tuberculous atlantoaxial dislocation includes ventral cervicomedullary decompression, occipitocervical arthrodesis, and administration of antituberculous medications. METHODS Eighteen patients with tuberculous atlantoaxial dislocation who presented with neck pain and/or occipital headache, restriction of neck movement, difficulty swallowing, and signs of myelopathy were studied. Four patients had evidence of associated pulmonary tuberculosis. Plain x-rays of the cervical spine, computed tomographic scans, and magnetic resonance images were obtained in all patients for diagnosis and to assess the degree of dislocation and cervicomedullary compression. Simultaneous anterior neural decompression, via a transcervical retropharyngeal approach, and posterior arthrodesis were performed on all patients while they remained under anesthesia. Antituberculous chemotherapy was continued for 18 months. RESULTS Histopathological analysis of excised tissue was consistent with tuberculosis in all patients. However, Ziehl-Neelsen staining for acid-fast bacilli was positive in two cases, and culture for Mycobacterium tuberculosis was negative in all patients. Patients with severe myelopathy experienced marked improvement. One patient died of fulminant resistant tuberculous meningitis. CONCLUSION The transcervical retropharyngeal approach to the craniovertebral junction provides direct access to the lesion and avoids the potential bacterial contamination of the oral and pharyngeal cavity. It also prevents the development of persistent fistulae. Posterior stabilization should be performed directly after anterior neural decompression, while the patient remains under anesthesia, to prevent neurological deterioration before subsequent posterior fixation. This technique also is helpful for early mobilization of patients. The aim of surgical treatment should be to obtain biopsy tissue and to perform radical excision of epidural granulation tissue/abscess and infected bone using microsurgical technique. Antituberculous medication must be continued for 18 months with four drug regimens, and continuous monitoring of drug toxicity should be performed throughout the course of treatment.

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Uniplanar cannulated pedicle screws in the correction of Lenke type 1 adolescent idiopathic scoliosis (AIS)

10.21203/rs.3.rs-34233/v1 ◽

2020 ◽

Author(s):

Yiwei Zhao ◽

Wubo Liu ◽

Suomao Yuan ◽

Yonghao Tian ◽

Xinyu Liu

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Pedicle Screws ◽

Vertebral Rotation ◽

Concave Side ◽

Convex Side ◽

X Rays ◽

Group A ◽

Group B

Abstract Background In the present study, we reported the clinical use of uniplanar cannulated pedicle screws for the correction of Lenke type 1 adolescent Idiopathic scoliosis (AIS), and its safety and clinical outcomes were also evaluated. Methods 68 patients with Lenke type 1 AIS were included, among which 38 patients were treated with uniplanar cannulated screws at the concave side of periapical levels and multiaxial screws at the other levels (group A). Moreover, the remaining 30 patients were treated with all multiaxial screws (group B). The preoperative and postoperative radiographic parameters of the Lenke type 1 AIS, axial vertebral rotation, and the safety of the pedicle screws were evaluated by X-rays and computed tomography (CT). Results Preoperative data was comparable between two groups. The postoperative proximal thoracic (PT) curve, main thoracic (MT) curve, thoracolumbar/lumbar (TL/L) curve, and apical vertebral rotation were significantly improved compared with the preoperative data. The coronal correction rates in group A and B were 83% and 81.9%, respectively (P > 0.05). The derotation rates in group A and B were 60.8% and 43.2%, respectively (P < 0.05). The rotation classification in the group A was also better compared with the group B. The misplacement rate in group A and B was 7.9% and 11.8%, respectively (P < 0.05), and the total misplacement rate on the concave side (11.4%) was higher than that of convex side (8.4%). The lateral perforation was found at the concave side, while the medial perforation was found at the convex side. On the concave side, the misplacement rate in group A and B was 9.7% and 12.3%, respectively (P < 0.05). The grades 2 and 3 perforations were three (3.5%) in the group A and eight (8.2%) in the group B (P < 0.05). On the convex side, the misplacement rate in group A and B was 5.9% and 11.1%, respectively (P < 0.05). The grades 2 and 3 perforations were one (0.9%) in the group A and four (4.4%) in the group B (P < 0.05). Conclusion Collectively, uniplanar cannulated pedicle screws could effectively increase the accuracy of pedicle screws and facilitate the derotation of the apical vertebra compared with the multiaxial pedicle screws. Trial registration retrospectively registered

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Anatomical and radiologic characteristics of isthmus parameters in guiding pedicle screw placement

Journal of International Medical Research ◽

10.1177/0300060518762986 ◽

2018 ◽

Vol 46 (6) ◽

pp. 2386-2397 ◽

Cited By ~ 1

Author(s):

Paerhati Rexiti ◽

Yakufu Abulizi ◽

Aikeremujiang Muheremu ◽

Shuiquan Wang ◽

Maierdan Maimaiti ◽

...

Keyword(s):

Pedicle Screw ◽

Pedicle Screws ◽

Screw Placement ◽

Lumbar Spine Surgery ◽

X Rays ◽

Pedicle Screw Placement ◽

Chinese Han ◽

Before And After ◽

Placement Accuracy ◽

D Value

Objective To study the clinical application of lumbar isthmus parameters in guiding pedicle screw placement. Methods Lumbar isthmus parameters were measured in normal lumbar x-rays and cadaveric specimens from a Chinese Han population. Distance between the medial pedicle border and lateral isthmus border was recorded as a ‘D’ value and was compared between X-rays and cadavers. Orthopaedic surgeons estimated different distances (2–6 mm) and angles (5–20°), and bias ratios between estimated and real values were compared. Orthopaedic residents placed pedicle screws on cadaveric specimens before and after application of the ‘D’ value, and screw placement accuracy was compared. Results Except for L4 vertebrae, significant differences in the ‘D’ value were found between 25 cadaveric specimens and x-ray films from 120 patients. Distances and angles estimated by 40 surgeons were significantly different from all real values, except 2 mm distance. Accuracy of pedicle screw placement by six orthopaedic residents was significantly improved by applying the ‘D’ value. Conclusions Surgeon estimates of distance were more accurate than angle estimates. Addition of a ‘D’ value to conventional parameters may significantly improve pedicle screw placement accuracy in lumbar spine surgery.

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Physician Compliance With Bronchiolitis Guidelines in Pediatric Emergency Departments

Clinical Pediatrics ◽

10.1177/0009922819850462 ◽

2019 ◽

Vol 58 (9) ◽

pp. 1008-1018 ◽

Cited By ~ 2

Author(s):

Andrea V. Rivera-Sepulveda ◽

Terri Rebmann ◽

James Gerard ◽

Rachel L. Charney

Keyword(s):

Online Survey ◽

Pediatric Emergency ◽

Systemic Steroid ◽

X Rays ◽

Chi Square ◽

X Ray ◽

American Academy Of Pediatrics ◽

Physician Compliance ◽

Chest X Ray ◽

Viral Testing

An online survey was administered through the American Academy of Pediatrics (AAP) Section of Emergency Medicine Survey Listserv in Fall, 2017. Overall compliance was measured as never using chest X-rays, viral testing, bronchodilators, or systemic steroids. Practice compliance was measured as never using those modalities in a clinical vignette. Chi-square tests assessed differences in compliance between modalities. t tests assessed differences on agreement with each AAP statement. Multivariate logistic regression determined factors associated with overall compliance. Response rate was 47%. A third (35%) agreed with all 7 AAP statements. There was less compliance with ordering a bronchodilator compared with chest X-ray, viral testing, or systemic steroid. There was no association between compliance and either knowledge or agreement with the guideline. Physicians with institutional bronchiolitis guidelines were more likely to be practice compliant. Few physicians were compliant with the AAP bronchiolitis guideline, with bronchodilator misuse being most pronounced. Institutional bronchiolitis guidelines were associated with physician compliance.

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Prevalence of Coracoclavicular Joint in Patients Visiting Radio-Diagnosis Department at College of Medical Sciences, Chitwan

Journal of Chitwan Medical College ◽

10.3126/jcmc.v9i3.25789 ◽

2019 ◽

Vol 9 (3) ◽

pp. 84-89

Author(s):

Ruku Pandit ◽

Sunara Shrestha ◽

Nitasha Sharma

Keyword(s):

Shoulder Pain ◽

Goodness Of Fit ◽

Coracoid Process ◽

X Rays ◽

Synovial Joint ◽

Medical Sciences ◽

Goodness Of Fit Test ◽

Chi Square ◽

And Gender ◽

Coracoclavicular Joint

Introduction: Coracoclavicular joint (CCJ) is a true synovial joint between superior surface of coracoid process of scapula and conoid tubercle of clavicle. The radiological prevalence of CCJ in various population ranges 0.55% to 21%. The CCJ are mostly discovered incidentally and is rarely associated with any symptom. Sometimes it may present with shoulder pain, limitation of shoulder movement, upper limb paresthesia and osteoarthritis of itself or adjacent acromioclavicular joint. Hence, this study is aiming to determine the prevalence of anomalous CCJ in patient visiting department of Radio-diagnosis in College of Medical Sciences, Bharatpur, Chitwan, Nepal and to observe association of CCJ with laterality, sides and gender. Methods: A total of 1936 digital chest x-rays films were observed for the presence of CCJ, out of which 1097 images were of male and 839 of females. Age of study population ranged from 3 to 90 years. The data obtained were analyzed using Stastical Package for Social Science version (SPSS) 16.0. The prevalence of CCJ was calculated. The cases with CCJ were further analyzed to evaluate the association of CCJ with laterality, sidedness and gender using Chi-square for one-dimensional “goodness of fit” test. Chi-square of Independence was employed to compare the various parameters (laterality and side) with genders. Results: The prevalence of CCJ was 4.6%. CCJ was more frequently observed in male (67.42%) than female (32.57%). Unilateral occurrence of CCJ (55.06%) was slightly more than bilateral (44.94%). Gender difference was not significantly associated with laterality and sidedness of joint (p<0.05). The incidence of CCJ was more in second decade of life in both male and female. Conclusion: CCJ is not rare, hence, knowledge of presence of CCJ as an etiology of shoulder pain is essential for rational therapy and will prevent misdiagnosis.

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Biomechanics of a lumbar interspinous anchor with anterior lumbar interbody fusion

Journal of Neurosurgery Spine ◽

10.3171/2009.10.spine09305 ◽

2010 ◽

Vol 12 (4) ◽

pp. 372-380 ◽

Cited By ~ 37

Author(s):

Dean G. Karahalios ◽

Taro Kaibara ◽

Randall W. Porter ◽

Udaya K. Kakarla ◽

Phillip M. Reyes ◽

...

Keyword(s):

Interbody Fusion ◽

Plate Fixation ◽

Pedicle Screws ◽

Axial Rotation ◽

Anterior Lumbar Interbody Fusion ◽

Lumbar Interbody Fusion ◽

Lateral Bending ◽

Anterior Plate ◽

Foraminal Height ◽

Flexion And Extension

Object An interspinous anchor (ISA) provides fixation to the lumbar spine to facilitate fusion. The biomechanical stability provided by the Aspen ISA was studied in applications utilizing an anterior lumbar interbody fusion (ALIF) construct. Methods Seven human cadaveric L3–S1 specimens were tested in the following states: 1) intact; 2) after placing an ISA at L4–5; 3) after ALIF with an ISA; 4) after ALIF with an ISA and anterior screw/plate fixation system; 5) after removing the ISA (ALIF with plate only); 6) after removing the plate (ALIF only); and 7) after applying bilateral pedicle screws and rods. Pure moments (7.5 Nm maximum) were applied in flexion and extension, lateral bending, and axial rotation while recording angular motion optoelectronically. Changes in angulation as well as foraminal height were also measured. Results All instrumentation variances except ALIF alone reduced angular range of motion (ROM) significantly from normal in all directions of loading. The ISA was most effective in limiting flexion and extension (25% of normal) and less effective in reducing lateral bending (71% of normal) and axial rotation (71% of normal). Overall, ALIF with an ISA provided stability that was statistically equivalent to ALIF with bilateral pedicle screws and rods. An ISA-augmented ALIF allowed less ROM than plate-augmented ALIF during flexion, extension, and lateral bending. Use of the ISA resulted in flexion at the index level, with a resultant increase in foraminal height. Compensatory extension at the adjacent levels prevented any significant change in overall sagittal balance. Conclusions When used with ALIF at L4–5, the ISA provides immediate rigid immobilization of the lumbar spine, allowing equivalent ROM to that of a pedicle screw/rod system, and smaller ROM than an anterior plate. When used with ALIF, the ISA may offer an alternative to anterior plate fixation or bilateral pedicle screw/rod constructs.

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Is postoperative bracing after pedicle screw fixation of spine fractures necessary? Study protocol of the ORNOT study: a randomised controlled multicentre trial

BMJ Open ◽

10.1136/bmjopen-2017-019596 ◽

2018 ◽

Vol 8 (1) ◽

pp. e019596 ◽

Cited By ~ 1

Author(s):

Arjen Johannes Smits ◽

Jaap Deunk ◽

Agnita Stadhouder ◽

Mark Cornelis Altena ◽

Diederik Hendrik Ruth Kempen ◽

...

Keyword(s):

Rating Scale ◽

Numerical Rating Scale ◽

Scientific Journal ◽

Pedicle Screws ◽

Length Of Hospital Stay ◽

Postoperative Treatment ◽

Posterior Fixation ◽

Spine Fractures ◽

Treatment Protocols ◽

Randomised Controlled

IntroductionThe most common surgical treatment of traumatic spine fractures is through a posterior approach using pedicle screws and rods. Postoperative treatment protocols including the use of postoperative orthoses however differ between hospitals and surgeons. A three-point hyperextension orthosis is designed to support proper posture and unload the anterior column. Some motion remains when wearing an orthosis, and its main value in postoperative treatment is therefore believed to be pain relief and patient confidence. This could consequently shorten recovery time. On the other hand, an orthosis could also lead to muscle weakness and slow down recovery. Any orthosis-related complications might also be avoided. Additionally, recent studies on conservative fracture treatment show no difference in radiological outcomes with or without an orthosis. To date, no randomised studies have been performed on the use of postoperative orthoses.Methods and analysisPatients undergoing posterior fixation with pedicle screws for a traumatic thoracolumbar fracture (T7–L4) will be included in this randomised controlled multicentre non-inferiority trial. Forty-six patients will be randomised 1:1 to one of the two parallel groups; one group will wear a postoperative orthosis for 6 weeks followed by 6 weeks of weaning and one group will not wear an orthosis. The primary outcome is pain at 6 weeks reported on the Numerical Rating Scale. Secondary outcomes consist of pain on other moments, analgesic use, complications and length of hospital stay, quality of life (EuroQuol 5 Dimensions), back pain-related function (Oswestry Disability Index) and radiological outcomes with a follow-up of 1 year. Orthosis compliance is monitored weekly in the orthosis group.Ethics and disseminationThe institutional review board (METc VUmc) approved this study on 11 October 2016 under case number 2016.389. After completion of the trial, the results will be offered to an international scientific journal for peer-reviewed publication.Trial registration numberNCT03097081and NTR6285; Pre-results.

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Outcomes Assessment of Multi-Level Sleep Surgery in Syndromic Versus Non-Syndromic Children

Annals of Otology Rhinology & Laryngology ◽

10.1177/0003489419900201 ◽

2020 ◽

Vol 129 (6) ◽

pp. 556-564

Author(s):

Suqrat Munawar ◽

Alexander P. Marston ◽

Terral Patel ◽

Shaun A. Nguyen ◽

David R. White

Keyword(s):

Length Of Stay ◽

Sleep Disordered Breathing ◽

Healthcare Research ◽

Chi Square ◽

Sleep Surgery ◽

Obstructive Sleep ◽

Significant Difference ◽

Potential Risks ◽

Multi Level ◽

Inpatient Database

Objectives: Analyze the differences in length of stay, cost, disposition, and demographics between syndromic and non-syndromic children undergoing multi-level sleep surgery. Methods: Children with sleep disordered breathing or obstructive sleep apnea that had undergone sleep surgeries were isolated from the 1997 to 2012 editions of the Kids’ Inpatient Database, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality. Children were then classified as syndromic or non-syndromic and stratified by level of sleep surgery (tonsillectomy & adenoidectomy, tonsillectomy & adenoidectomy plus other site surgery, other site surgery). Length of stay and cost were reported with Kruskal–Wallis one-way analysis of variance, disposition with binomial logistic regression, and demographics with chi-square. Results: Syndromic children compared to non-syndromic children were more likely to have surgery beyond just tonsillectomy & adenoidectomy and also had a longer length of stay, higher total cost and non-routine disposition (all P < .001). Syndromic children undergoing tonsillectomy and adenoidectomy plus other site surgery had a longer length of stay compared to syndromic children undergoing tonsillectomy & adenoidectomy (6.00 days vs 3.63 days, P < .001). However, no similar statistically significant difference in length of stay was found in non-syndromic children (2.01 days vs 2.87 days, P > .05). Conclusion: The potential risks/benefits need to be weighed carefully before undertaking sleep surgery in syndromic children. They experience a longer length of stay, higher cost, and non-routine disposition when compared to non-syndromic children. This is especially true when considering the transition from tonsillectomy & adenoidectomy to tonsillectomy & adenoidectomy plus other site surgery, as syndromic children experience a longer length of stay and non-syndromic children do not.

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