The presence of the synchondrosis between the dens and the body of C-2 makes this injury unique to children under 7 years of age; by the age of 7 the synchondrosis has fused. PMID: 8577504 [Indexed for MEDLINE] MeSH terms. Child, Preschool; Female; Humans; Male; Odontoid Process/diagnostic imaging; Odontoid Process/growth & development. The authors report an unusual case of an odontoid synchondrosis fracture causing chronic translational anterior atlanto-axial subluxation and present a discussion of the unique management of this case. Traumatic translational anterior atlanto-axial subluxation is a rare manifestation within pediatrics
There is effacement of CSF signal anterior to the cord at the base of the odontoid, immediately superior to the subdental synchondrosis (SDS; arrow). The space available for cord (SAC, indicated by the thick horizontal white line) measures less than 13 mm External orthosis is the accepted and historical management of odontoid synchondrosis fractures; however, this conservative therapy carries a significant complication and fracture nonunion rate among young children. The purpose of this study was to evaluate the authors' own experience in the context There was synchondrosis between the odontoid and the body of the axis and the cephalad part of the odontoid was detached. Bilateral ischiopubic ossification defects and ischiopubic and odontoid synchondroses were additional abnormalities. 3D-CT scan showed an orthotopic type of os odontoideum associated with an occult axial fracture synchondrosis fracture; and delayed, incomplete bony fusion of the odontoid process relative to his age. The cause of his death was a superior spinal cord injury. The tissue surrounding the upper cervical spine presented with myositis ossificans, suggesting a prior injury. He experienced a minor traffic accident
the apex of the odontoid process (os terminale) between 3 and 6 years of age and fuses by age 12 years. The body of C2 fuses with the odontoid process by 3-6 years of age. This fusion line (sub-dental synchondrosis), or the remnant of the car-tilaginous synchondrosis, can be seen until age 11 years and may be confused with a fracture. Th Fracture through the body of the odontoid peg. Fracture of right anterior arch of C1. Bilateral congenital non-union of the posterior arch at accessory lateral synchondroses (the bone margin here is very defined) The synchondrosis between the base of the odontoid process and the body of the axis does not fully ossify until a child is six to seven years of age and hence is particularly prone to traumatic injury [ 26 ] The odontoid synchondrosis fractures are one of the more common fractures in very young children [ 1 ]. External immobilization has been advocated and bears a good outcome [ 1 ] The odontoid synchondroses are cartilaginous articulations separating the odontoid process from the body of the axis .They normally become fully fused between the ages of five and seven years, usually forming a line on radiographs until 11 years; so most cases involving fracture of the synchondrosis are in children [1-3].In this report, we present a rare case of an accessory odontoid.
Odontoid synchondrosis fractures, although rare in the overall incidence of spinal trauma, are one of the more common fractures in young children Introduction. In embryologic developmental stages, vertebra C2 forms from 5 ossification centers (the 2 neural arches, the body, the odontoid process, and the chondrum terminale, or os odontoideum) 1 separated by 6 C2 synchondroses. Five of these are central: the right and left odontoneural synchondrosis, the right and left neurocentral synchondrosis (separating odontoid and body from neural. An odontoid process fracture and calcification and fibrosis of the muscles around the superior cervical vertebra were observed during the autopsy. Postmortem computed tomography revealed an anterior dislocation of the atlas; odontoid synchondrosis fracture; and delayed, incomplete bony fusion of the odontoid process relative to his age . INTERVENTION: The patient was placed in a halo vest shortly after admission. Four days after his injury, he underwent a posterior wiring and fusion of C6 to C7
Management of the odontoid synchondrosis fracture remains a controversial topic in children of younger age group. Introduction. The cervical spine is a region with maximal mobility, owing to which it has greater chances of injury. The common causes of injury are motor vehicle accidents and sports-related injuries The latter occur because of the presence of physiological odontoid synchondrosis, but fractures can result from trivial injuries as well as from high-energy trauma. The persistence of an infantile odontoid, with a large pre-adulthood head in children with skeletal dysplasias, is a major risk factor for sudden death or significant morbidity Odontoid synchondrosis fractures are rare in children, even though they are the more common cervical fracture in children less than 7 years old. Nonoperative treatment with external orthosis immobilization is the treatment of choice for stable undisplaced or minimally displaced injuries C2 synchondrosis fractures in children younger than 7 years have been described as slip fractures or odontoid synchondrotic slip fractures, with two forms previously described [9, 10]. Hosalkar et al. [ 4 ] classified the more common synchondrosal fracture type into three subtypes based upon degree of anterior displacement of the odontoid.
Epiphysiolysis Injury of the odontoid: This is a fracture of the odontoid that is peculiar to young children. It occurs at the dentocentral synchondrosis. Epiphysiolysis injury in a 22-month-old child after MVA:The injury has occurred through the C2 synchondrosis. The fracture was reduced under fluoroscopy and managed with a halo vest for 2 months The secondary ossification center at the apex of the odontoid appears between ages 6 and 8 years and fuses with the dens around the age of 12 years. (b) Correlative coronal CT from a 6-month-old child shows the synchondrosis between the odontoid and body of C2, the neurocentral synchondroses, and an early apical ossification center for the. Odontoid synchondrosis fractures were detected in the Despite the fact that there is a 43% complication rate and up to 10% of the failure of fusion was reported, Halo ortho-sis has been observed to be the most beneficial approach in the two limited clinical series.12,18 New modifications in the Hal
Body of C2 and Odontoid Synchondrosis The synchondrosis between the odontoid and body of C2 may simulate a fracture from birth until it closes, between ages 3 and 7 years When it is partially fused it may appear as an incomplete fracture of the odontoid 5. Body of C2 and Odontoid Synchondrosis The tip of the dens is a derivative of the proatlas. The odontoid process at birth is separated from the body of the axis by a cartilaginous band that represents a vestigial disk. This is referred to as the neurocentral synchondrosis. The band lies below the level of the superior articular facets of the axis
Os Odontoideum. - See: Development and Anomalies of the Axis: - Discussion: - dens may be completely absent, hypoplastic, or incompletely fused to body of C2 (lesion called os odontoideum) - the os odontoideum is smaller than the normal dens but size may vary; - the base of the dense is almost always hypoplastic; - it is located usually in. This synchondrosis normally fuses by 5-7 years of age but may remain open into adolescence . True fractures will result in an anteriorly displaced and angulated odontoid process with a preserved atlantodental interval [16, 29]. However, nondisplaced fractures of the synchondrosis (odontoid epiphysiolysis) may be difficult to detect Os Odontoideum. Os odontoideum is believed to be caused by a previous fracture of the odontoid synchondrosis before its closure at the age of 5 to 6 years, while smaller, persistent ossiculum terminale is due to failure of the secondary ossification center of the dens to fuse with the base of the odontoid. Os odontoideum typically appears as a. The average ratio of odontoid/body was two in pediatric and 1.8 in adult cases. This study demonstrated that the neck of the odontoid segment at the level of superior articulating facets is not the synchondrosis between the odontoid process and the body of C2. The synchondrosis is located well below the level of superior articulating facets
The cervical plain film showed a loss of continuity of odontoid synchondrosis suggesting a fracture and subluxation of the atlas on the axis and the instability of atlantoaxial joint (Fig. 1). Noncontrast computed tomography (CT) and magnetic resonance imaging (MRI) with gadolinium enhancement were performed for further investigation Due to the anatomic differences in children, four types of odontoid fracture in pediatric patients with open synchondrosis were defined by Hosalkar. 9 Type I with three subtypes describes fractures at the level of the subdental synchondrosis. Up to 10% of displacement equals subtype IA, 11% to 100% displacement to IB and IC is defined by more. Conclusion Synchondrosis fractures of the odontoid are rare and usually found in children under 7 years of age. Most of these patients can be treated by external immobilization alone. However, in small children with significant displacement and angulation, posterior C1-C2 fusion is a better option providing more stability
Odontoid fractures in young children are rare. Most authors advocate for closed reduction and external stabilization as first line treatment. Unlike adults, young children are much less amenable. A literature review was conducted to compare the authors' management strategy with those in published data. External orthosis for treatment of odontoid synchondrosis fractures has a strong history of success. However, in the literature, patients treated with a halo orthosis had a 43.3% rate of complications and an 11.4% risk of nonunion The odontoid synchondrosis fracture represents a rare but typical injury of the upper cervical spine in children less than 7 years. Conservative treatment with closed reduction and external fixation shows fusion rates across the synchondrosis in about 90% cases. When closed reduction cannot be achieved, open reduction and internal fixation is.
The computed tomography/magnetic resonance imaging shows regeneration of the odontoid process compressing the brain stem with an increase in syringohydromyelia. We suggest that there is a need for the removal of the complete odontoid process with periosteum and also beyond the dentocentral synchondrosis to prevent late recurrences of odontoid. <section class=abstract><p>External orthosis is the accepted and historical management of odontoid synchondrosis fractures; however, this conservative therapy. bony impingement of the anterior portion of the foramen magnum on the odontoid process. age when sub dental synchondrosis fuses. 6yo. classification of odontoid fractures. andersen and D'alonzo (location of fracture) Type 1 odontoid fx. oblique avulsion of the tip of the dens. type 2 odontoid fx. fracture through th waist. type 3 odontoid fx
Odontoid fractures in children less than 7 years of age occur at the subdental synchondrosis and are typically diagnosed with plain x-rays. However, a delay in diagnosis is common as these injuries may not be appreciated on initial roentgenographic evaluation Odontoid synchondrosis fractures in children. Neurosurg Focus 2006;20:E7. Hosalkar HS, Greenbaum JN, Flynn JM, et al. Fractures of the odontoid in children with an open basilar synchondrosis. J Bone Joint Surg Br 2009;91:789-96. Sherk HH, Nicholson JT, Chung SM. Fractures of the odontoid process in young children by the odontoid synchondrosis at the point of maximal head ﬂ exion during trauma. 5 Other factors that predispose to odontoid synchondrosis injury in the young child would be the under-developed neck and paravertebral muscles, physiological ligamentous laxity and horizontal orientation of the facet joints. Cord injury associated with such. Nontraumatic unfused odontoid synchondrosis; Os odontoideum: 1. Sequela of odontoid synchondral fracture prior to union at age 5-7. 2. The disruption occurs at the cartilaginous plate between dens and the body of axis. 3. Ossicle posterior to the transverse atlantal ligament (TAL). 4. Atlantoaxial instability is more common with os odontoideum
first and second cervical sclerotomes contribute to the odontoid and axis bodies, respectively [4-5]. After birth, the odontoid has an epiphyseal growth plate separating the first and second cervical sclerotomes known as the neurocentral synchondrosis, which lies below the level of th odontoid process, and 2 for the neural arches. The odontoid process fuses by the seventh gestational month. At birth, a vestigial cartilaginous disc space called the neurocentral synchondrosis separates the odontoid process from the body of C2. The synchondrosis is seen in virtually all children aged 3 years and is absent in those aged 6 years This is thought to occur secondary to a previous fracture of the synchondrosis and may cause instability. Conversely, a persistent ossiculum terminale is due to failure of fusion of the secondary ossification centre, closer to the tip of the odontoid process than the synchondrosis, and may mimic a type 1 fracture ( Fig. 18 ) 
The centrum and odontoid centers fuse between 3 and 6 years of age across the subdental synchondrosis. A secondary ossification center known as the os terminale forms at the cranial tip of the odontoid by 3 years old and fuses with the odontoid by 12 years old. The C3 through L5 vertebrae are similar in their patterns of development A particular site of proneness to synchondrosis fracture is the odontoid synchondrosis . Fig. 28.2 Synchondrosis fracture. Lateral radiograph of the upper cervical spine of a 1-year-old girl with a history of trauma shows the odontoid process anteriorly displaced and angulated ( white arrowhead ) relative to the C2 vertebral body ( red arrowhead ) Odontoid fracture is a potentially devastating injury that is often subtle and underreported on cervical spine radiographs by radiologists and emergency physicians. AI meeting this use case would help to reduce the false negative rate, patient risk, and medicolegal risk for physicians and facilities involved in the care of trauma patients Type II odontoid fractures represent the most common pattern of dens injury (54-60%) and occur through the base of dens at the junction of the C-2 vertebral body .[13 14 15] In children, the fracture may occur through the synchondrosis between the dens and body of C-2
A, Normal midline synchondrosis. B, Rare paramedial posterior synchondrosis. C, Rare midline OC within the PAA. Fig 6. Ossification timetable of the posterior atlas arch. Fig 7. Coronal (A) and sagittal (B) view of the neonatal axis with 5 OCs. A, While both club-shaped centers of the dens are already fused at birth, a midline vertical fusion. synchondrosis typically fuses between 3 and 5 years of age, and the anterior synchondro-ses fuse between 5 and 8 years of age. The axis develops from five primary ossifi-cation centers: two vertically oriented odontoid centers, two neural arches, and one centrum (Fig. 2). The two odontoid centers usually fuse before birth Normal synchondrosis • Odontoid angulation (4%) • Basilar subdental synchondrosis (>7ys) • Pseudosubluxation (<9yrs) • ADI < 5mm (why? ligamentous laxity & cartilage components in kids) • RSTS • Normal anterior body wedging <7yrs • Horizontal facets as pillar fxs • Single-level kyphosis (16%
In this model, os odontoideum develops gradually. Following a fracture of the odontoid synchondrosis, with growth, the alar ligaments carry the dens fragment away from the axis base. The cranial portion of the dens fragment continues to receive a blood supply from the vascular arcade Neurocentral synchondrosis: The epiphyseal growth plate that separates the first and second cervical sclerotomes. Terminal apical arcade of blood vessels - The odontoid process depends on this arcade mostly for its blood supply and this anastomoses caudally with the deep penetrating branches arising from the posterior ascending arteries the odontoid process of C2 is separated from the vertebral body by a cartilaginous band called subdental synchondrosis. Usually, this synchondrosis does not fully close and partly persist into adult age. Because of the minor resistance of this synchondrosis, shear stress like in hyperflexion movements leads to dislocation of the odontoid This coalescence is termed the subdental synchondrosis . A cause of the abnormally-shaped odontoid process in our patient may be the growth of the apex being distinct from the odontoid body. This apical secondary ossification center fuses with the remainder of the odontoid process by 12 years of age . The presented case most likely had an.
A digital caliper with an accuracy of 0.01 cm was used for the height of the odontoid process, which was measured from its tip to the remnant of the dentocentral synchondrosis, below the level of the plane passing through the superior articular facets as indicated by the study of Cokluk et al. and Akobo S et al. (figure 1) . An osteometric. Cervical Spine Anatomy. the limited blood supply in this watershed area is thought to affect healing of type II odontoid fractures. The superior articular facets of the subaxial cervical spine (C3-C7) are oriented in a posteromedial direction at C3 and posterolateral direction at C7, with a variable transition between these levels - subdental synchondrosis scar may remain as a remnant of this fusion; - Odontoid (dens) - two separate centers appear by the fifth fetal month and fuse w/ each other by the 7 th fetal month; - Synchondrosis between odontoid and neural arch: - fuses at 3 to 6 years At birth, there is an epiphyseal growth plate called the neurocentral synchondrosis that separates the body of the axis (C-2) from the dens (C-1). This synchondrosis is not located at the base of the dens, but is well below the level of the superior articulating facet of the axis and into its body. The blood supply to the odontoid is also unique Now its clear that failure of the secondary ossification center of the dens to fuse with the base of the odontoid represents a separate entity known as persistent ossiculum terminale and the Os odontoideum actually represents a previous fracture of the odontoid synchondrosis before its closure at age 5-6 years
Overriding C1 over Tip of Odontoid (C2) Seen in extension; 20% of those between 1 and 7 years of age. Result of non-ossified atlas and tip of odontoid; Also anterior angulation of odontoid process in as many as 4%; Persistence of Basilar Odontoid Synchondrosis: Can mimic odontoid fracture; Sometimes present until 11 years of ag Anteversion of odontoid is the angulation anomaly seen at the synchondrosis of C2 body and odontoid process. As the anteversion angle increases, there is an increased chance of cord compression by the body of axis (the offending element) rather than the tip of the odontoid. Management guidelines of this anomaly remains the same as that of any. Odontoid fractures in children younger than seven years of age represent a disruption through the cartilage plate (synchondrosis) that connects the odontoid to the body and neural arches of the axis1,2. Unrecognized and untreated fractures of the odontoid3-5 and acute ligamentous injuries6 in young children may compromise the vascularity of the process, causing the development of an os.
Key Words: C2 · Synchondrosis · Odontoid Fractures · Axis · Cervical Spine · Computed Tomography · Magnetic resonance imaging · child . 5 Introduction: The pediatric spine, like a mature adult spine, is broken into regions: cervical, thoracic, lumbar, sacrum and coccyx. The cervical spine, the upper most region, is comprised of 7 vertebra However, two additional centers form in the base of the dens and fuse into a single odontoid center, either by birth or a few months later (Fig. 3.5) [8, 9]. The ossification centers of the body and dens are separated by a well-demarcated synchondrosis, the homologue of the disc between C1 and C2 (Fig. 3.6) The odontoid has a different blood supply from the rest of the spine. The neurocentral synchondrosis precludes a rostral vascular supply by the anterior and posterior branches of the vertebral artery. As a result, the odontoid process depends significantly on a terminal descending supply superiorly, called the apical arcade A case is presented that illustrates the use of computerized tomography for the evaluation of an odontoid fracture in a child. Such a 'fracture' may actually represent a 'synchondrotic slip' of the odontoid and C-2 vertebral body between the neural arches of C-2. Treatment should almost always be conservative During skeletal development the two ossification centers of the odontoid process are separated from the corpus of the axis by a subdental synchondrosis. This synchondrosis is thought to close and disappear spontaneously in adolescence although this has never been studied in detail. The basis of the dens is of clinical relevance as type II dens fractures are located here. To characterize the.
The odontoid process is separated from the body of the axis vertebra by a vestigial disk that later becomes the subdental synchondrosis. The remainder of the axis is formed by the second cervical sclerotome [ 3 - 5 ] This is more indicative of an odontoid fracture. Widening of the subdental synchondrosis coupled with anterior tilting of the odontoid are highly indicative of an odontoid fracture. A Type III odontoid fracture extends into the vertebral body of C2. The odontoid image shows three open mouth odontoid radiographs on the right
DOAJ is a community-curated online directory that indexes and provides access to high quality, open access, peer-reviewed journals The synchondrosis prevents direct vascularization of the odontoid from C2, and vascularization from the blood supply of C1 is not possible because the synovial joint cavity surrounds the odontoid. The formation of an os odontoideum after cervical trauma may be related to this peculiar blood supply ( Fig. 23-11 ) The odontoid process forms from two independent ossification centers that appear during the 5th fetal month and. Fig. 3.44. Ossiculum terminale in a 10-year-old girl. Note the presence of an ossicle lying at the top of odontoid process and clearly separated from it. The ossiculum terminale is relatively large in this case. (From Currarino 2001 Type II odontoid fracture. This 4-year-old child suffered a hyperflexion injury when he was struck in the head by a truck tailgate. A. A lateral radiograph shows anterior displacement of the odontoid process and widening of the synchondrosis. The C2 spinous process projects posterior to the posterior cervical line due to anterior displacement.
Odontoid synchondrosis fractures in children. Spine E 14407 19597911 Subbiah V 2010. Of mice and men: divergent risks of teriparatide-induced osteosarcoma. Basic Science L 3 D. persistent subdental synchondrosis 14 What is the name given to the joint formed between the tip of the dens and the odontoid process centers of ossification Type II fracture of odontoid process of axis; Information for Patients Fractures. Also called: Broken bone. A fracture is a break, usually in a bone. If the broken bone punctures the skin, it is called an open or compound fracture. Fractures commonly happen because of car accidents, falls, or sports injuries. Other causes are low bone density.
Orthotopic os odontoideum (see the image above) may appear free and in a relatively anatomic position, where it may be difficult to differentiate from an unfused neurocentral synchondrosis, odontoid hypoplasia, or odontoid fracture nonunion. In children younger than 5 years, the neurocentral synchondrosis often has not fused The synchondrosis between the odontoid and axis body was noted as a lucency in all children imaged up to the age of 4 years. The synchondrosis remained visible in half the children up to 11 years of age. The authors also described an absence of the normal cervical lordosis in 14% of subjects, most commonly in the 8- to 16-year-old age groups.. Dr. Daniel R. Fassett is a Neurosurgeon in Peoria, IL. Find Dr. Fassett's phone number, address, insurance information, hospital affiliations and more dens not fused, take flexion/extension views, potential to be unstable, size variable, position of the odontoid tip at or near the basal occiput, gap usually extends above the level of the superior facets, is wide, and as smooth edge, previous fracture of the odontoid synchondrosis before its closure at age 5-6yr
Odontoid synchondrosis fractures in children. Neurosurg Focus 2006;20:E7 ; Jones TM, Anderson PA, Noonan KJ. Pediatric cervical spine trauma. J Am Acad Orthop Surg 2011;19:600-11. Platzer P, Thalhammer G, Ostermann R, et al. Anterior screw fixation of odontoid fractures comparing younger and elderly patients.. A, the neurocentral synchondrosis (small arrow) lies below the level of the superior articular facets of the axis and does not represent anatomic base of the dens.It is often visible beneath the gap (large arrow) between the ossicle and the remnant dens. B, the odontoid process relies on a terminal descending supply from the apical arcade (arrow).). The rostrally migrated and remodeled ossicle. 1. Odontoid (dens): Two separate centers appear by the fifth fetal month and fuse with each other by seventh fetal month. J. Synchondrosis between odontoid and neural arch: Fuses at three to six years. L. Synchondrosis between odontoid and body: Fuses at three to six years. M. Posterior surface of body and odontoid. Fig. 2 Dr. Cuong Bui is a Neurosurgeon in New Orleans, LA. Find Dr. Bui's phone number, address, insurance information, hospital affiliations and more When do the centers of ossification for the odontoid process first appear? during the last trimester in utero. What joint is formed between the odontoid process ossification centers and the centrum of C2? the subdental synchondrosis
Study Transition Zones of the Vertebral Column flashcards from Tom Andersen's class online, or in Brainscape's iPhone or Android app. Learn faster with spaced repetition Odontoid synchondrosis fractures in children. Spine E 11022 16113180 Harty JA, EMJ 2005. Odontoid lateral mass asymmetry: do we over-investigate? Spine D PDF: 11023 20595131 Hsu WK, JAAOS 2010. Odontoid fractures: update on management. General D 11024 17622873.