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European Spine Journal : Official... Jul 2015Use of pedicle screws has been popularized in the treatment of pediatric spinal deformity. Despite many studies regarding the effect of pedicle screws on the immature...
PURPOSE
Use of pedicle screws has been popularized in the treatment of pediatric spinal deformity. Despite many studies regarding the effect of pedicle screws on the immature spine, there is no study concerning the impact of addition of crosslink to pedicle-screw-based instrumentation on the development of the spinal canal in young children. This study aims to determine the influence of the screw-rod-crosslink complex on the development of the spinal canal.
METHODS
This study reviewed 34 patients with congenital scoliosis (14 boys and 20 girls) who were treated with posterior-only hemivertebrectomy and pedicle-screw-based short-segment instrumentation before the age of 5 years. The mean age at surgery in this cohort was 37 ± 11 months (range 21-57 months). They were followed up for at least 24 months. Of these patients, 10 underwent only pedicle screw instrumentation without crosslink, and 24 with additional crosslink placement. The vertebrae were divided into three regions as follows: (1) S-CL (screw-crosslink) region, in which the vertebrae were inserted with bilateral pedicle screws and two rods connected with the crosslink; (2) S (screw) region, in which the vertebrae were inserted with bilateral pedicle screws but without crosslink; (3) NS (no screws) region, which comprised vertebrae cephalad or caudal to the instrumented region. The area, anteroposterior and transverse diameters of the spinal canal were measured at all vertebrae on the postoperative and last follow-up computed tomography axial images. The instrumentation-related parameters were also measured, including the distance between the bilateral screws and the screw base angles. The changes in the above measurements were compared between each region to evaluate the instrumentation's effect on the spinal canal growth.
RESULTS
The mean follow-up was 37 ± 13 months (range 24-68 months) and the mean age at the last follow-up was 74 ± 20 months (range 46-119 months). In each region, the spinal canal dimensions significantly increased during the follow-up period. There was no significant difference in the spinal canal growth rate between the S and NS regions or between the S-CL and NS regions. Besides, a comparison of the S-CL and S regions regarding the changes in the measurements of the instrumentation construct revealed no significant differences.
CONCLUSION
Pedicle-screw-based instrumentation does not cause retardation of the development of the spinal canal in young children. Moreover, use of the crosslink added to the screw-rod instrumentation also demonstrates no negative effect on the growth of the spinal canal. Thus, the addition of the crosslink to short screw-based instrumentation is recommended as an alternative to increase fixation stability in growing patients, even in very young pediatric population.
Topics: Child, Preschool; Female; Follow-Up Studies; Humans; Infant; Male; Multidetector Computed Tomography; Pedicle Screws; Retrospective Studies; Scoliosis; Spinal Canal; Spinal Fusion
PubMed: 25527403
DOI: 10.1007/s00586-014-3727-7 -
European Journal of Radiology Aug 2012Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the...
OBJECTIVES
Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI).
PATIENTS AND METHODS
Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age.
RESULTS
ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r>0.8). A simple linear model MSCD (mm)=3×Weight (kg)+5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model.
CONCLUSION
There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm)=3×Weight (kg)+5 could result in fewer traumatic LPs in this population.
Topics: Cadaver; Female; Humans; Magnetic Resonance Imaging; Male; Organ Size; Reproducibility of Results; Sensitivity and Specificity; Spinal Canal
PubMed: 22609321
DOI: 10.1016/j.ejrad.2012.02.003 -
AJNR. American Journal of Neuroradiology 1986We investigated the MR appearance and incidence of low-signal areas within the CSF of the spinal canal. Nonuniform areas of decreased signal intensity in intracranial...
We investigated the MR appearance and incidence of low-signal areas within the CSF of the spinal canal. Nonuniform areas of decreased signal intensity in intracranial CSF have been named the CSF flow-void sign (CFVS) and appear to be due to spin dephasing secondary to pulsatile CSF motion. Similar areas are seen in the spinal canal. The MR scans of 50 randomly selected patients, constituting a total of 63 spinal studies, were reviewed. There were 27 cervical, 16 thoracic, and 20 lumbar spine examinations. All patients were studied using T2-weighted and T1-weighted spin-echo pulse sequences. T2-weighted images were done with sufficiently long TE and TR to cause the CSF to appear hyperintense compared with brain and spinal cord tissue. Two patients with enlarged spinal canals and two patients with syringohydromyelia were also included to illustrate the appearance of prominent CSF pulsations. The CFVS was identified on T2-weighted scans in the cervical spinal canal in nine patients (33%), in the thoracic spinal canal in one patient (6%), and possibly in the lumbar spinal canal in two patients (10%). The CFVS was prominent in two patients with enlarged CSF spaces and was also seen in the intramedullary cavity of the patients with syringohydromyelia. The CFVS could obscure small dural lesions and, in some instances, simulate enlarged vessels. Recognition of the spinal CFVS is important to avoid the incorrect diagnosis of intraspinal lesions.
Topics: Adolescent; Adult; Aged; Cerebrospinal Fluid; Child; Child, Preschool; Female; Humans; Magnetic Resonance Spectroscopy; Male; Middle Aged; Pulsatile Flow; Rheology; Spinal Canal
PubMed: 3096108
DOI: No ID Found -
Regional Anesthesia and Pain Medicine 1999Important issues regarding the spread of solutions in the epidural space and the anatomy of the site of action of spinal and epidural injections are unresolved. However,...
BACKGROUND AND OBJECTIVES
Important issues regarding the spread of solutions in the epidural space and the anatomy of the site of action of spinal and epidural injections are unresolved. However, the detailed anatomy of the spinal canal has been incompletely determined. We therefore examined the microscopic anatomy of the spinal canal soft tissues, including relationships to the canal walls.
METHODS
Whole mounts were prepared of decalcified vertebral columns with undisturbed contents from three adult humans. Similar material was prepared from a macaque and baboon immediately on death to control for artifact of tissue change after death. Other tissues examined included nerve root and proximal spinal nerve complex and dorsal epidural fat obtained during surgery. Slides were examined by light microscopy at magnifications of 10-40x.
RESULTS
There is no fibrous tissue in the epidural space. The epidural fat is composed of uniform cells enclosed in a fine membrane. The dorsal fat is only attached to the canal wall in the dorsal midline and is often tenuously attached to the dura. The dura is joined to the canal wall only ventrally at the discs. Veins are evident predominantly in the ventral epidural space. Nerve roots are composed of multiple fascicles which disperse as they approach the dorsal root ganglion. An envelope of arachnoid encloses the roots near the site of exit from the dura.
CONCLUSIONS
These features of the fat explain its semifluid consistency. Lack of substantial attachments to the dura facilitate movement of the dura relative to the canal wall and allow distribution of injected solution. Fibrous barriers are an unlikely explanation for asymmetric epidural anesthesia, but the midline fat could impede solution spread. Details of nerve-root structure and their envelope of pia-arachnoid membrane may be relevant to anesthetic action.
Topics: Adipose Tissue; Aged; Aged, 80 and over; Animals; Decalcification Technique; Epidural Space; Female; Humans; Macaca; Male; Middle Aged; Papio; Photomicrography; Spinal Canal; Spine
PubMed: 10445768
DOI: 10.1016/s1098-7339(99)90103-7 -
JPMA. the Journal of the Pakistan... Oct 1989To assess the normal dimensions of the lumbar spinal canal, 100 normal healthy subjects of either sex between 25 and 45 years age were x-rayed for lumber vertebral...
To assess the normal dimensions of the lumbar spinal canal, 100 normal healthy subjects of either sex between 25 and 45 years age were x-rayed for lumber vertebral column in both posteroanterior and lateral views and the canal was measured by Jones and Thomson method. The lumbar spinal canal showed constant dimensions in both sexes in all age groups when studied separately in the male and female subjects. However, no change in relative dimensions was observed between 25 and 45 years. The canal showed gradual decrease in measurement from L1 to L5 vertebral levels in both sexes but relative width of the canal was more in the females than in the males of the same age group. The normal values of the canal to vertebral body ratio (C/B) varies between 1:2.0 and 1:5.0. The ratio 1:2.0 indicates a wider canal whereas any ratio beyond 1:5.0 would be conclusive of stenosis of the lumbar vertebral canal.
Topics: Adult; Female; Humans; Lumbar Vertebrae; Male; Middle Aged; Radiography; Sex Factors; Spinal Canal
PubMed: 2513423
DOI: No ID Found -
RoFo : Fortschritte Auf Dem Gebiete Der... Jun 2021
Topics: Aged; Carcinoma; Fatal Outcome; Female; Humans; Interdisciplinary Communication; Magnetic Resonance Imaging; Mucin-1; Palliative Care; Sarcoma; Spinal Canal; Thoracic Wall
PubMed: 32882732
DOI: 10.1055/a-1237-4330 -
Asian Journal of Surgery Nov 2023
Topics: Humans; Neuroendocrine Tumors; Spinal Canal
PubMed: 37328381
DOI: 10.1016/j.asjsur.2023.06.015 -
Spine Dec 2006Measurements of cross sections of exit foramen and spinal canal were performed before and after placement of X Stop in physiologic postures using positional MR scanner... (Comparative Study)
Comparative Study
STUDY DESIGN
Measurements of cross sections of exit foramen and spinal canal were performed before and after placement of X Stop in physiologic postures using positional MR scanner at the stenosed level in patients with lumbar spinal stenosis.
OBJECTIVE
To quantify the effect of the implant in vivo on the lumbar spine at the instrumented levels in various postures.
SUMMARY OF BACKGROUND DATA
Dimensions of the spinal canal and neural foramen decrease from flexion to extension. Symptoms of spinal stenosis occur typically in standing or extension. The X Stop device is designed to distract the posterior elements of the stenotic segment and place it in flexion to treat neurogenic claudication. We think that the device will improve the dimension of the canal in standing and extension.
METHODS
Twenty-six patients with lumbar spine stenosis underwent a one- or two-level X Stop procedure. All had preoperative and postoperative positional MRI in standing, supine, and sitting flexion and extension. Measurements were carried out on the images acquired.
RESULTS
Significant increase in the dimensions of the neural foramen and canal area were demonstrated after surgery.
CONCLUSIONS
The X Stop device improves the degree of central and foraminal stenosis in vivo.
Topics: Aged; Aged, 80 and over; Female; Humans; Internal Fixators; Lumbar Vertebrae; Male; Middle Aged; Prospective Studies; Radiography; Spinal Canal; Spinal Stenosis
PubMed: 17139227
DOI: 10.1097/01.brs.0000247797.92847.7d -
Seminars in Ultrasound, CT, and MR Dec 1993This article reviews the normal anatomy of the bony and soft tissue structures of the lateral lumbar spinal canal. Thorough knowledge of these imaging anatomy helps in...
This article reviews the normal anatomy of the bony and soft tissue structures of the lateral lumbar spinal canal. Thorough knowledge of these imaging anatomy helps in making the correct diagnosis of the lumbar spinal lesions. CT and MRI are excellent tools to diagnose lateral lumbar spinal canal stenosis. Both CT and MRI provide the accurate measurements of the midsagittal and lateral spinal canals and show the abnormalities of the nerve root course. This review provides anatomic and radiographic descriptions of the lateral lumbar spinal canal and the anatomically related joints.
Topics: Humans; Lumbar Vertebrae; Magnetic Resonance Imaging; Spinal Canal; Spinal Stenosis; Tomography, X-Ray Computed
PubMed: 8297633
DOI: 10.1016/s0887-2171(05)80034-4 -
Spine Nov 1996A cadaveric study was done to analyze the dimensional changes in the spinal canal and intervertebral foramen of the lumber spine with flexion and extension movements.
STUDY DESIGN
A cadaveric study was done to analyze the dimensional changes in the spinal canal and intervertebral foramen of the lumber spine with flexion and extension movements.
OBJECTIVES
To investigate the relationship between flexion and extension movements and morphologic changes in the spinal canal and the intervertebral foramen.
SUMMARY OF BACKGROUND DATA
Previous studies have reported that the dimensions of the spinal canal and the intervertebral foramen may change significantly with motion. The purpose of this study was to assess the quantitative changes in the spinal canal and the intervertebral foramen with segmental flexion-extension movements.
METHODS
Nineteen fresh cadaveric spines yielding 25 motion segments were used. The lumbar motion segments were frozen and then imaged in axial and sagittal projections by a computed tomography scanner. They were thawed then, and the motion segments were loaded to 5.7 Nm in flexion (13 motion segments) and in extension (12 motion segments) specimens. While in flexion or extension, the specimens again were frozen and imaged by computed tomography scan. The frozen specimens than were sliced using a cryomicrotome in the sagittal plane to study the dimensions of the intervertebral foramen. Eighteen other fresh cadaveric spines were sliced sagittally for study in the neutral position.
RESULTS
The axial computed tomography scans showed that extension significantly decreased the canal area, midsagittal diameter, and subarticular sagittal diameter, whereas flexion had the opposite effects. The sagittal computed tomography scans showed that extension decreased all the foraminal dimensions significantly, whereas flexion increased all the foraminal dimensions significantly. The translational changes were associated with the bulging of the disc and the presence of traction spurs. The cryomicrotome sections showed the cross-sectional area of the foramen to be 12% greater for the flexion group and 15% smaller for the extension group than the cross-sectional area of the neutral group. Nerve root compression in the foramen was found to be 21.0% in neutral, 15.4% in flexion, and 33.3% in extension groups.
CONCLUSIONS
The study supports the concept of dynamic spinal stenosis. In addition to static anatomic changes, careful dynamic studies may be required to evaluate better the central canal and the foramen.
Topics: Adult; Aged; Aged, 80 and over; Cadaver; Female; Humans; Lumbar Vertebrae; Male; Middle Aged; Movement; Nerve Compression Syndromes; Range of Motion, Articular; Spinal Canal; Tomography, X-Ray Computed
PubMed: 8923625
DOI: 10.1097/00007632-199611010-00002