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A SPECTRUM OF VERTEBRAL SYNOSTOSIS

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Vertebrae and their intervertebral discs are one of the chief manifestations of body segmentation or metamerism. The differentiation and resegmentation of vertebrae occur at the time of organogenesis. Thus resegmentation is the hallmark of vertebral development .Inappropriate vertebral fusion results in block vertebra or spinal fusion or vertebral synostosis. It can occur at various levels viz., cervical, lumbar and thoracicvertebral levels in the order of frequency. A study was conducted at Dr. B. R. Ambedkar medical college, with vertebral and skull specimens collected from 1 st year MBBS students for duration of three years. Three different specimens of fused vertebrae were found; Assimilation of atlas, fused 6 th and 7 th cervical vertebrae and fused 1 st and 2 nd thoracic vertebrae. The clinical implications and embryological significance of these three specimens is discussed. INTRODUCTION Vertebrae and intervertebral discs are one of the main manifestations of body segmentation or metamerism (Standring, 2008). The bodies of vertebrae, thus formed by metamerism can be fused partially or completely. Such fusion of vertebral bodies is called as vertebralsynostosis or Spinal fusion or Block vertebrae. Theaetiology of this abnormality can be congenital / acquired or surgical. Congenital block vertebrae can result in syndrome manifestations such as KlippelFeil syndrome or may cause spine deformations such as Scoliosis. Acquired fusion of vertebrae is due to diseases such as Tuberculosis, Juvenile rheumatoid arthritis and trauma (Erdil et al., 2003). Presence of fused vertebrae results in biomechanical stress in the adjoining segments leading to premature degenerative changes at adjoining motion segments (Shankar, 2011). METHODS A study of two hundred and seventy vertebrae and one hundred and thirty six skulls was done for a period of three years (2009, 2010 and 2011). The vertebral and skull specimens were collected from students of 1 st year MBBS of batch 2009, 2010 and 2011.Ethical committee clearance was obtained. Inclusion criteria: All intact adult specimens were selected. Exclusion criteria: Broken, neonatal skulls were excluded.
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International Journal of Basic and Applied Medical Sciences ISSN: 2277-2103 (Online)
An Online International Journal Available at http://www.cibtech.org/jms.htm
2012 Vol. 2 (2) May-August, pp.71-77/Kulkarni and Ramesh
Research Article
71
A SPECTRUM OF VERTEBRAL SYNOSTOSIS
*Vasudha Kulkarni1 and B.R.Ramesh2
1Department of Anatomy, DRBRAMC, Bangalore
*Author for Correspondence
ABSTRACT
Vertebrae and their intervertebral discs are one of the chief manifestations of body segmentation or
metamerism. The differentiation and resegmentation of vertebrae occur at the time of organogenesis.
Thus resegmentation is the hallmark of vertebral development .Inappropriate vertebral fusion results in
block vertebra or spinal fusion or vertebral synostosis. It can occur at various levels viz., cervical, lumbar
and thoracicvertebral levels in the order of frequency. A study was conducted at Dr. B. R. Ambedkar
medical college, with vertebral and skull specimens collected from 1st year MBBS students for duration of
three years. Three different specimens of fused vertebrae were found; Assimilation of atlas, fused 6th and
7th cervical vertebrae and fused 1st and 2nd thoracic vertebrae. The clinical implications and embryological
significance of these three specimens is discussed.
Key Words: Spinal Fusion, Vertebralsynostosis, Block Vertebra
INTRODUCTION
Vertebrae and intervertebral discs are one of the main manifestations of body segmentation or
metamerism (Standring, 2008). The bodies of vertebrae, thus formed by metamerism can be fused
partially or completely. Such fusion of vertebral bodies is called as vertebralsynostosis or Spinal fusion or
Block vertebrae. Theaetiology of this abnormality can be congenital / acquired or surgical.
Congenital block vertebrae can result in syndrome manifestations such as KlippelFeil syndrome or may
cause spine deformations such as Scoliosis. Acquired fusion of vertebrae is due to diseases such as
Tuberculosis, Juvenile rheumatoid arthritis and trauma (Erdil et al., 2003).
Presence of fused vertebrae results in biomechanical stress in the adjoining segments leading to premature
degenerative changes at adjoining motion segments (Shankar, 2011).
METHODS
A study of two hundred and seventy vertebrae and one hundred and thirty six skulls was done for a period
of three years (2009, 2010 and 2011). The vertebral and skull specimens were collected from students of
1st year MBBS of batch 2009, 2010 and 2011.Ethical committee clearance was obtained.
Inclusion criteria: All intact adult specimens were selected.
Exclusion criteria: Broken, neonatal skulls were excluded.
RESULTS AND DISCUSSIONs
In the present study, three different specimens of fused vertebrae were identified.
Assimilation of Atlas: Fusion of atlas with basiocciput.
Cervical Vertebral Synostosis: Fusion of cervical vertebrae at 6th and 7th level.
Thoracic Vertebral Synostosis: Fusion of thoracic vertebrae at 1st and 2nd level.
Assimilation of Atlas
The occipital condyles of basiocciput were replaced by inferior articular facet of atlas. A small triangular
gap was present at the line of fusion of basiocciput and anterior arch of atlas.
Anterior arch and transverse process of atlas was well developed but posterior arch was totally
absent.Theantero-posterior length of foramen magnum was 32 mm and transverse diameter was 22 mm.
Area of foramen magnum was calculated by formula:
Area of foramen magnum =  ∗
∗ (22) ∗ ℎ(32)=553.14mm2
International Journal of Basic and Applied Medical Sciences ISSN: 2277-2103 (Online)
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2012 Vol. 2 (2) May-August, pp.71-77/Kulkarni and Ramesh
Research Article
72
Where w= transverse diameter of foramen magnum and h = anteroposterior length of foramen magnum.
The dimensions of foramen magnum were within normal limits thus osseous malformations causing
neurological compression were ruled outSaini (2009).
Figure 1: Base of Skull with Assimilation of atlas, Figure 2: Close up view of assimilation of atlas,
Figure 3: Anterobasal view showing gap between basiocciput and atlas. (Aa – Anterior arch of atlas,
Ab Pa Absence of posterior arch of atlas, Bo Basiocciput, Fm Foramen magnum, Ft Foramen
tranversarium, Iaf – Inferior articular facet, o triangular gap between basiocciput and atlas, To Torus
occipitale)
Cervical Vertebral Synostosis
Their bodies and articular facets were fused but laminae and spinous processes were unfused. A definitive
Figure 1: Anterior view, Figure 2: Left lateral view, Figure 3: Right lateral view, Figure 4: Superior
view of 6th and 7th cervical vertebral synostosis, Figure 5: Lateral Radiograph, Figure 6:
Anteroposterior Radiograph of 6th and 7th cervical vertebral synostosis. (Bd – Bodies of fused
vertebrae, Fj – Facet joint, Ft – Foramen tranversarium, La – lamina, Sp –Spine, Uafj – Unfused articular
facet joint, W/ R- Waist / ridge at the site of fused bodies, *- Partial slit at the site of fused vertebral
bodies)
International Journal of Basic and Applied Medical Sciences ISSN: 2277-2103 (Online)
An Online International Journal Available at http://www.cibtech.org/jms.htm
2012 Vol. 2 (2) May-August, pp.71-77/Kulkarni and Ramesh
Research Article
73
intervertebral foramen was present between these two fused vertebrae. The height of fused bodies of 6th
and 7th vertebrae was 1.1 cm. Articular processes were partially fused on left side and unfused on right
side. Anteriorly, bodies were completely fused represented by a waist or ridge. Internally, bodies were
partially fused with a partial slit. Spine and laminae remainedunfused.Radiograph of the cervical and
thoracic fused vertebral specimens were taken in anteroposterior and lateral views. Radiograph of fused
cervical vertebrae showed hypoplastic intervertebral disc.
Thoracic Vertebral Synostosis
There was asymmetric fusion of 1st and 2nd thoracic vertebrae with the bodies and laminae fused more on
left side .Their spinous processes remained unfused. Intervertebral foramen was larger on right side and
smaller on left side. The costal facet was well defined at the junction of fused bodies on left side. Height
of fused vertebral bodies measured 2.1cm on right lateral side, 0.8cm left lateral side. Intervertebral
foramen was oval in shape on right side and triangular on left side. Articular facets were completely
fused. A slit persisted on right lateral side of bodies indicating incomplete fusion. Lateral radiograph of
fused thoracic spine revealed posterior remnant of intervertebral disc.
Figure 1: Superior view, Figure 2: Right lateral view, Figure 3: Left lateral view of 1st and 2nd
thoracic vertebral synostosis, Figure 4: Lateral Radiograph, Figure 5: Anteroposterior Radiograph
of 1st and 2nd thoracic vertebral synostosis. (Bd – Bodies of fused vertebrae, Fbd – Asymmetrically
fused vertebral bodies, Fl- Fused laminae, If Intervertebral foramen, La lamina, Pd pedicle, Sp
Spine, Ubd – Unfused vertebral bodies,T1- 1st thoracic vertebra, T2 – 2nd thoracic vertebra)
Assimilation of Atlas
It refers to abnormal cranial shifting of the occipitocervical border. Assimilation of atlas is the cranial
most fused vertebrae. It has to be differentiated from Occipitilisation of atlas which is the caudal shifting
of the atlas and Manifestation of the occipital vertebrae which are structures/parts of atlas seen around
foramen magnum. Occipitilisation can be partial or complete fusion of atlas with the occiput. If atlas is
assimilated, the occipital condyles are replaced by the inferior facets of the atlas Bergman (1993).
There is a male preponderance of Assimilation of atlas upto 5:1 ratio with a high incidence of upto 0.75-
3%. Partial assimilation of atlas is more common than total assimilation (Altunkas et al., 2009).
Based on the etiology, Swjetschnikow classified three types of atlanto-occipital fusion;
Acquired type due to Tuberculosis, Syphilis, Arthritis deformans etc.
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Table 1: Incidence of assimilation of atlas as reported by various authors
S. No. Author Incidence
1 James R.Grilliot(1988) 0.08%- 3%
2 Adel Afifi Bergman(1993) 0.5%- 1%
3 VineetaSaini(2009), Kassim(,2010) 0.14%- 0.75%, 0.5- 1.5% in Caucasians
4 J.Skrzat(2010) 0.1%-0.8%, 1.09% in Asians
Acquired by fetus in utero by pelvic pressure as known as Basikyphosis of Virchow. Schniffner put
forward theory called as DRUCK theory stating that “during delivery, pushing inwards of parts of
occipital bone around foramen magnum results in Basikyphosis”.
Purely congenital type occurring at the time of Sclerotome differentiation Smith (1907).
In the present case, there is also absence of posterior arch of atlas along with its tubercle which fits into
type E. Other types of posterior arch defect of atlas (Kwon et al., 2009) are:
Failure of posterior midline fusion of the two hemiarches. Sometimes a small separate ossicle is seen
within the gap.
Unilateral cleft, ranging from a small gap to a complete absence of the hemiarch and posterior tubercle.
Bilateral clefts of the lateral aspects of the arches with preservation of the most dorsal part of the arch.
Complete absence of the posterior arch with a persistent isolated tubercle. This anomaly is relatively a
more extensive form of bilateral clefts. The lateral parts of the posterior arch are absent except for the
posterior tubercle.
Assimilation of atlas is commonly associated with type A posterior arch defect. It can be associated with
clinical symptoms such as weakness and paresthesia of all four limbs, chronic neck pain and headache
(Kwon et al., 2009).
Clinical Significance
Assimilation of atlas may be coexistent with basilar invagination, protrusion of odontoid process into
foramen magnum. Thus the size and configuration of foramen magnum must be evaluated to rule out
accompanying osseous malformations. Decreased height of atlas at the time of fusion with occiput is the
cause of basilar compression resulting in muscular weakness, ataxia, muscular spasticity and hypereflexia
(Grilliot et al., 1988). Neurological symptoms of assimilation of atlas resemble that of tumours in the
region of foramen magnum, known as Foramen magnum syndrome. It may cause medullo-spinal
compression ventrally or vertebrobasilarin sufficiency due to dorsal compression (Iwata et al., 1998).
70% of patients with assimilation of the atlas will have congenital fusion of cervical vertebrae at the level
of C2 C4. It may also be associated with atlanto-occipital subluxation, hypertrophic odontoid process
with brain stem compression (Grilliot et al., 1988).
Recent technique to detect assimilation of atlas is Open mouth Tomography (Cone et al., 1981).
Developmentally, occipital condyles and articular facets of atlas, tip of odontoid process are derived from
proatlas, the cranial portion of 4th occipital sclerotomes. Thus failure of segmentation of the vertebral
column results in the occurrence of assimilation of atlas (Cone et al., 1981).Posterior arch defect of atlas
is attributed to failure of development of cartilaginous preformation of atlas. The defect is also associated
with syndromes such as KlippelFeil, Arnold Chiarimal formation, Turner and Down’s syndromes (Kwon
et al., 2009).
Case of congenital vertebral fusion and assimilation of atlas to occipital bone is a further stage of
evolutionary process. During transition from fish to amniote, many vertebrae become fused and
assimilated to occipital bone. An addition of another vertebra to already absorbed cranium is a feature of
amniote cranium. Thus Assimilation of atlas is a progressive modification of vertebrae whereas
Occipitilisation of atlas is a regressive type of modification (Smith, 1907).
International Journal of Basic and Applied Medical Sciences ISSN: 2277-2103 (Online)
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2012 Vol. 2 (2) May-August, pp.71-77/Kulkarni and Ramesh
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75
Cervical and Thoracic Vertebral Synostosis
Spinal fusion is the hallmark of KlippelFeil syndrome, a triad of short neck, low posterior hair line and
restricted neck mobility.
Maurice Kippel and Andre Feil, 1912 described three types of vertebral synostosis;
Massive fusion of cervical and upper thoracic vertebrae.
Fusion of interspace, hemivertebrae, occipitoatlanto fusions.
Cervical, thoracic and lumbar fusions (Samartis et al., 2006).
Wasp Waist sign (Anterior concave indentation at the site of absent or reduced inter space between fused
vertebrae in a radiograph) is associated with complete vertebral fusion in KlippelFeil syndrome (Yuksel et
al., 2005).
Fusion of vertebrae can occur in sequence of common occurrence in cervical, lumbar and thoracic region.
Surgical fusion of vertebrae is known as Spondylodesis or Spondylosyndesis. It can also be a congenital
or acquired abnormality.
Cervical spine is invariably an anomalous constitution of clinical cases of Willet – Sprengel shoulder,
brevicollis, kyphosis, congenital deafness, renal agenesis, cardiovascular abnormalities etc., (Cave, 1933-
1934).
Radiologically, Johan et al., (2007 ) described three types of vertebral fusion : Single fused cervical
segment seen in 25% of patients, multiple ,contiguous fused segments seen in 25% patients and multiple ,
non-contigious fused seen in 50% patients.
Sequence of presentation of vertebral synostosis is: C5-C6, C1-C2, C4-C5 followed by C6-C7fusion
(Clarke et al., 1995).Prevalence of vertebral synostosisin Lithuanian population is 2.6% of
cervicalvertebralfusion, 1.6% of thoracicvertebralfusion and 0.5% of Lumbar vertebral fusion (Masnicova
et al., 2003).
Clinical Complications
Vertebral synostosis can be associated with radiculopathy and myelopathy. Various syndrome
associations.
Table2: Complications associated with vertebral synostosis with their percentage of incidence
(Batra et al., 2008)
S. No Associated Complications Percentage
of Incidence
1 Neural axis – Diastematomyelia, Tethered cord, Arnold Chiari malformation. 35%
2 Renal – Unilateral horseshoe kidney, Duplicated kidney/ ureters,
Hypospadias. 25%-33%
3 Congenital heart disease – Atrial septal defect, Ventricular septal defect,
Tetralogy of Fallot, Transposition of great vessels. 10%
4
Musculoskeletal
-
Clubfeet, Sprengel’s deformity,
KlippelFeil syndrome
Dysplasia of hip, scoliosis
71%
60%
5 Jaw, external ear abnormalities, cleft palate, cervical ribs 20%
of vertebral fusion are Segmentation syndrome1 with laryngeal malformation, VACTERL(S)(Vertebral,
Anal, Cardiovascular, Tracheo- Esophageal, Renal and Limb abnormalities+_single umbilical artery),
MURC (Mullerian duct aplasia, Renal aplasia, Cervicothoracic somite dysplasia), Hemifacialmacrosomia,
Diabetic embryopathy, Alagille, Trisomy 18, Escobar(Autosomal recessive cervical vertebral fusion,
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2012 Vol. 2 (2) May-August, pp.71-77/Kulkarni and Ramesh
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76
ptosis, hypertelorism of neck, axillae, genital anomalies and small stature), Joubert, Jarcho - Levin
syndrome (Victor, 2010).
Pathological causes of fusion of vertebrae are Fibrodysplasia, Progressive Juvenile Rheumatoid arthritis,
Postinfectious, Postsurgical, Ossification of posterior longitudinal ligament of cervical spine,
Posttraumatic etc. (Clarke et al., 1995)
The differentiation and resegmentation of vertebrae occurs at the time of organogenesis. This explains the
association of vertebral synostosis with cardiac, renal, musculoskeletal and neural abnormalities (Lettset
al., 2009).
Embryological Significance
Fused vertebrae or block vertebrae are caused by non-segmentation of the primitive Sclerotome. The
anatomy of fused vertebrae indicates the embryological time of occurrence of synostosis: Independent
pedicle and transverse process suggests normal initial development followed by fusion.
Ridge on dorsal surface of fused arches indicates that fusion has occurred after initial development and
differentiation.
Absence of the joint between articular facets in the fused vertebrae suggests failure of normal
development and differentiation of vertebraei.e.Fusion at the precartilaginous stage of vertebral
development (Chandraraj et al., 1987).
The sum of height of congenitally fused vertebral bodies is equal to normal height of intervertebral disc if
one were present whereas vertebral fusion due to disease has sum of height of fused bodies is less than
normal height of intervertebral disc if one were present (Kumar et al., 1988).
Molecular basis
Familial KlippelFeil syndrome is on locus of Chromosome 8q.An inversion of inv(8)(q22.2 q23.3)has
been found on 8q chromosome segregating with congenital vertebral fusion(Clarke et al., 1995). Mutation
occurs in Pax gene and notch signaling pathway . C2-C3 fusion is an autosomal dominant disorder and
C5- C6 fusion is an autosomal recessive disorder.
MorphologyAddition of vertebra to existing cranium is a feature of progressive variation.
CONCLUSIONS
Block vertebra result due to failure of resegmentation of vertebrae. It is associated with genitourinary,
neurological and musculoskeletal abnormalities. Fusion of vertebrae is named as KlippelFeil syndrome in
cervical region, Synspondylism in thoracic region, or Block vertebra in lumbar region. Though unrelated,
each of these cases is unique due to varied clinical presentations.
ACKNOWLEDGEMENTS
We extend our sincere thanks to our non - teaching staff who helped us and supported during the writing
of this manuscript. We also express our thanks to our institution, Dr.B.R. Ambedkar medical college and
all the faculty members for helping in presentation of this manuscript. I “had full access to all the data in
the study and I take responsibility for the integrity of the data and the accuracy of the data analysis.”
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... Congenital vertebral synostosis (CVS) is a rare developmental condition due to failure in the process of segmentation or metamerism, which usually occurs (in order of frequency) in the cervical, lumbar, and thoracic vertebral levels. Vertebrae and their intervertebral discs differentiate and resegment at the time of organogenesis during fetal life [1,2]. Resegmentation is the hallmark of vertebral development and involves metamerism, whereby vertebrae can be fused completely, both anterior and posterior elements being involved, or partially [1,3,4]. ...
... Vertebrae and their intervertebral discs differentiate and resegment at the time of organogenesis during fetal life [1,2]. Resegmentation is the hallmark of vertebral development and involves metamerism, whereby vertebrae can be fused completely, both anterior and posterior elements being involved, or partially [1,3,4]. Inappropriate vertebral fusion results in block vertebra or vertebral synostosis. ...
... CVS can be isolated or can result from syndromic manifestations such as KFS, MURC (Mullerian duct aplasia, renal aplasia, cervicothoracic somite dysplasia), Escobar (autosomal recessive cervical vertebral fusion, ptosis, hypertelorism of neck, axillae, genital anomalies, and small stature), VACTERL (vertebral, anal, cardiovascular, tracheoesophageal, renal and limb abnormalities or single umbilical artery), hemifacial macrosomia, diabetic embryopathy, segmentation syndrome 1 with laryngeal malformation, Trisomy 18, Alagille, Joubert, and Jarcho-Levin syndromes [1,8]. KFS is on the locus Chromosome 8q and is associated with inversion inv [15] (q22.2 q23.3), which is associated and segregated with congenital vertebral fusion [5]. ...
Article
Congenital vertebral synostosis (CVS) is a rare developmental condition due to failure of vertebral segmentation. Vertebrae and their intervertebral discs differentiate and resegment at the time of organogenesis during fetal life. Failure of this embryological process can result in the limitation of mobility of the involved segment. This inappropriate segmentation thus results in vertebral fusion or a block vertebra with subsequent vertebral synostosis. Long-term, such segmental fusion can increase osteoarthritis at levels below and above the fused segment due to excessive wear on these joints. Presentations can include congenital kyphosis and scoliosis. Patients may present with back and radicular pain, and possible myelopathy CVS usually occurs, in order of frequency, in the cervical, lumbar, and thoracic vertebral levels. This paper reviews congenital lumbar synostosis with associated findings and its clinical implications and embryological significance. A case illustration is also included.
... (1). The synostosis of vertebrae can be congenital or acquired (2). Acquired synostosis of the vertebrae can be secondary to tuberculosis, vertebral fusion surgery, juvenile rheumatoid arthritis, trauma, or other infections (3). ...
... Acquired synostosis of the vertebrae can be secondary to tuberculosis, vertebral fusion surgery, juvenile rheumatoid arthritis, trauma, or other infections (3). Fusion of the two vertebrae is called spondylosynthesis after surgery (2). Congenital -C3 ve C3-C4, T10-T11 ve T11-T12 ile L4-L5 intervertebral gövdede görüldü. ...
... Some studies have been done to investigate the frequency of spinal anomalies. Early detection of vertebral synostosis in the cervical, thoracic and lumbar regions may indicate the presence of congenital defects (2). Acquired vertebral fusion and congenital vertebral fusion can be distinguished by xray imaging or MR imaging (8). ...
Article
Full-text available
INTRODUCTION: This study was determined the incidence of synostosis of vertebrae at various regions and to compare the increase in synostosis level with increased pain and decreased range of motion METHODS: Seventy-eight adult vertebral columns were used to establish the incidence of congenital vertebral fusion in different spinal regions.The fusion was completed involving the bodies of the vertebrae without the vertebral arch. RESULTS: The incidence of congenital vertebral fusion was seen at the maximum in the cervical region(61.53%), then in the lumbar (21.79%) and thoracic regions(16.66%) in decreasing order.Visual analog scale scores in the cervical region were seen as 4.9+-1.3, then in the lumbar and thoracic regions as 4.5+-1.3 and 2.3+-1.4, respectively. Congenital vertebral fusion in the cervical, thoracal, and lumbar region, respectively, was most common between C2-C3 and C3-C4,T10-T11 and T11-T12, and the L4-L5 intervertebral bodies. In the cervical region, statistically significant changes were observed between single-level fusion and 2 or more fusions in terms of movement and visual analog scale scores;however, in the thoracic and lumbar regions, no statistically significant difference was observed.There was a statistically significant change in the range of motion in the thoracic and lumbar regions, except in lumbar extension. No patient underwent surgery. DISCUSSION AND CONCLUSION: We found that the frequency of congenital vertebral fusion was most common in the cervical region.We observed that as the number of intervertebral congenital vertebral fusions increased in all cervical,thoracic and lumbar regions, the pain increased and the range of motion decreased.Congenital vertebral fusion causes resistant back pain and decreases the range of motion.
... Caudal shifts in this area are a more common occurrence and can be expressed uni-or bilaterally (Kulkarni and Ramesh, 2012). They can cause the axis to become distorted as it assimilates into the skull base (Moore and Petty, 2005) and can also develop transverse foramina and/or demonstrate a complete anterior arch whilst the posterior arch is often incomplete (Barnes, 2012). ...
Thesis
This research aims to demonstrate how “form related to function” can be used to explain differences in the degree of zygapophyseal (facet) joint sexual dimorphism seen in populations with differing lifestyles. Whilst sex can be estimated with a reasonable degree of accuracy from the facet joints of the spine in populations with a high degree of sexual dimorphism, it can be problematic in samples that do not. Bone adapts to reflect the physiological strain placed upon it during life. Analysis of the relationship between bony adaptation to occupational stress and facet morphology identifies extrinsic factors that correlate to changes in facet size and to a lesser degree sagittal angle. Extrinsic factors are external biocultural influences on bone morphology (e.g. nutrition and physical activity). The number of discriminant functions that can be derived from a population with a low degree of sexual dimorphism is increased when these factors are included, increasing the potential to estimate sex. The strength of correlation and prevalence of extrinsic factors can also be used to measure the degree of physical activity undertaken by individuals and is indicative of gendered division of labour in the population under study. Analysis of facet size and sagittal angle and the relationship and prevalence of extrinsic factors related to physical activity from skeletal material were examined from three contrasting samples. Two were from 18th century London with differing socio-economic status and the third a composite sample from three 5th -7th century Anglo-Saxon cemeteries located in southeast England. A comparative study of facet size and angle identified inter-sample differences in the degree of sexual dimorphism. Further comparison of differences in lifestyle as evidenced by activity patterns was carried out to assess the impact of extrinsic factors on facet remodelling. In particular, this thesis focuses on evidence of the gendered division of labour as manifest by femoral robusticity, humeral directional asymmetry, vertebral osteophytosis, and osteoarthritis with analysis of the individual diagnostic criteria of eburnation, pitting and osteophytes. A distinct difference in prevalence of these factors was observed in the Anglo-Saxon sample and most obviously in females when compared with the 18th century samples, indicating that there was a difference in intensity of activity undertaken by this group in comparison with the other samples in this study. This suggests that the lack of facet joint sexual dimorphism observed in Anglo-Saxons is attributable to the degree of physical activity undertaken by these females and the subsequent remodelling of the facets as a functional adaptation to the mechanical loading they were subjected to. This research demonstrates that for some populations, sex can be estimated with reasonable accuracy from vertebral facet dimensions but for less dimorphic samples, inclusion of extrinsic factors related to physical activity when deriving discriminant functions increases the opportunity to estimate sex. Furthermore, analysis of inter-sample prevalence rates for extrinsic factors provides supporting evidence of different levels of physical activity between the samples.
... In the present study, we observed the presence of FCV between C5 and C6. FCV are most commonly found in C5-C6, C2-C3, C1-C2, and C6-C7, in decreasing order of incidence 10,11 . ...
... The differentiation and resegmentation of vertebrae occurs at the time of organogenesis. It explains the association of vertebral synostosis with cardiac, renal, musculoskeletal and neural abnormalities [16]. ...
... Various vertebral anomalies of Anatomic interest have been reported viz.; occipitalisation, sacralisation, lumbarisation, absence of posterior elements of vertebral arch and vertebral synostosis. Fusion of vertebra at single or multiple levels is referred to as block vertebrae or spinal fusion or vertebral synostosis [3]. Spinal meningiomas are common extraaxial solid lesions with distinguishing features, and most of them have a thoracic localization [4]. ...
Thesis
A holistic approach to palaeopathological studies using historical documentation and clinical, archaeological and epidemiological literature can provide important information as to the health, lifestyles, socioeconomic and occupational status of individuals from the past. Applying this approach, the study provides an overview and comparative analysis of the spinal health of two contemporaneous British skeletal samples from the medieval period; St Owen’s Cemetery, an urban based population from Gloucester (n=68) and Poulton a rural, agrarian community from Cheshire (n=70). Sex and age at death were estimated using a variety of osteological techniques and descriptive statistics and Chi-square statistical tests were computed to identify and assess inter- and intra-population differences. Although some significant differences were observed, both skeletal samples had similar types and anatomical locations of the pathological conditions observed. St Owen’s Cemetery exhibits higher frequencies of degenerative conditions and vertebral fractures, whereas Poulton displays higher frequencies of congenital conditions such as lumbosacral anomalies and cervical vertebral synostosis (possible Klippel-Feil Syndrome). Age of onset of degenerative conditions is markedly earlier in Poulton indicating occupational status from a younger age than their contemporaries in St Owen’s. Females are more affected by degenerative conditions and vertebral fractures than the males in both samples. The frequency of the aforementioned conditions increases dramatically with age suggesting the fractures could be related to osteoporosis. Significant differences were observed between population samples in the frequency of osteoarthritis in the thoracic segment of middle adult males and females in which St Owen’s exhibit double the amount. This indicates that biomechanical stresses were more likely to have been placed on the thoracic segment such as carrying heavier loads and repetitive bending and twisting in a singular occupational role in an urban setting such as a craft (cordwainer) or working for a merchant guild. Frequency of infectious lesions is comparable in both samples, indicating similar exposure to pathogens albeit there may be differences in the type of infections present. Males are more affected than the females in the rural sample suggesting that pathogens in the soil and livestock may be the cause of the lesions observed. The findings of this study are generally consistent with other published data, although frequency of vertebral trauma in the urban sample far exceeds other contemporary sites. The study presented here provides a glimpse into medieval life in both the large town and the rural farming community in the British Isles. Further studies include comparing data from more contemporary urban and rural populations to produce a more holistic study on medieval health and lifestyle in the British Isles including further analysis of larger skeletal samples from Poulton and St Owen’s. Additional observation of complete skeletons including body mass and stature and radiographic analyses will give further supportive evidence for some diagnoses.
Article
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Occipitalization of the atlas is a rare congenital malformation of the craniovertebral region. During anthropometric study of 126 human skulls in the Department of Forensic Medicine and Anatomy, two skulls were discovered, which exhibited assimilation of the atlas to the occipital bone. One female skull exhibited total assimilation with bifid posterior arch, while the other male skull exhibited partial occipitalization and partial vertebralization. The partial or complete assimilation of the atlas may have resulted due to disruption in the separation of the caudal part of the first sclerotome from the cranial part of the first sclerotome.
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An otherwise-healthy, active 83-year-old Nigerian man developed reversible central cord myelopathy from a mild fall on a level surface. Cervical spine magnetic resonance imaging (MRI) revealed C5, 6, and 7 block vertebrae and marked disc extrusions only at the immediately adjoining upper and lower non-fused segments of the cervical spine. There was no spinal canal stenosis otherwise. We think that the unique presentation of this case of Klippel-Feil syndrome further supports the impression that following fusion (congenital or acquired) of one segment of the spinal column, hypermobility of the non-fused adjoining segments may strongly predispose to more disc extrusions.
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Occipitalization of the atlas is an osseous anomaly of the craniovertebral junction. The aim of this paper is to present an anatomical variant of the fused atlas with the occipital bone and discuss similar cases described in literature. The skull of an adult male analysed in this study belonged to the cranial collection of the Department of Anatomy of the Jagiellonian University, Medical Collage. A tight bony fusion between the anterior arch of the atlas, the left portion of the posterior arch, the lateral masses of the atlas, and the occipital bone was observed. Hence, the left and right superior articular facets of the atlas were fused with the corresponding occipital condyles. The anteroposterior dimension of both inferior articular facets was the same (20 mm), while the transverse diameter of the right one was considerably smaller (12 mm). The transverse diameter of the left inferior articular facets was 17 mm. The right and the left transverse process of the atlas were normally developed, each of them contained transverse foramen, and they were not fused with the occipital bone. The circumference of the foramen magnum was minimally diminished by the osseous structures of the atlas fused to the occipital bone. The sagittal and transverse diameters of the foramen magnum (38 mm x 34 mm) were within the normal range of variation. However, the asymmetrical anatomy of the inferior articular facets of the atlas give rise to speculation that movement in the atlantoaxial joint was disturbed by assimilation with the occipital bone.
Article
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Atlantal arch defects are rare. Few cadaveric and imaging studies have been reported on the variations of such anomalies. Our goal in this study was to examine the incidence and review the clinical implications of this anomaly. A retrospective review of 1,153 neck or cervical spine computed tomography (CT) scans was performed to identify patients with atlantal arch defects. Neck CT scans were performed in 650 patients and cervical spine CT scans were performed in 503 patients. Posterior arch defects of the atlas were grouped in accordance with the classification of Currarino et al. In patients exhibiting this anomaly, special attention was given to defining associated anomalies and neurological findings. Atlantal arch defects were found in 11 (11/1153, 0.95%) of the 1,153 patients. The type A posterior arch defect was found in nine patients and the type B posterior arch defect was found in two patients. No type C, D, or E defects were observed. One patient with a type A posterior arch defect had an anterior atlantal-arch midline cleft (1/1153, 0.087%). Associated cervical spine anomalies observed included one C(6-7) fusion and two atlantal assimilations. None of the reviewed patients had neurological deficits because of atlantal arch anomalies. Most congenital anomalies of the atlantal arch are found incidentally during investigation of neck mass, neck pain, radiculopathy, and after trauma.
Article
Klippel-Feil Syndrome (KFS) is a complex congenital syndrome of osseous and visceral anomalies. It is mainly associated with multi-level cervical spine fusion with hypermobile normal segments. Therefore, a patient with KFS can be at risk of severe neurological symptoms even after a minor trauma. We report a patient with type III KFS who developed a hemiparesis after a minor trauma and was successfully managed with operation.
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The year 2008 marked the 150th anniversary of the publication of Gray's Anatomy. It was also the year when the 40th edition of this classic was released. When Henry Gray and Henry Vandyke Carter published their book, which they titled Anatomy, Descriptive and Surgical, it represented a change in the way anatomy texts were written and illustrated. As described in the Historical Introduction of this edition, they married written description to large, clear, well-labeled illustrations in a way that had not been done before. The model was a success, copied by many others such as Cunningham, Morris, and Buchanan in the United Kingdom and Gerrish and Piersol in the United States, as well as a number of authors writing in other languages. However, almost all of those other texts have disappeared; of the English-language books, only Gray's Anatomy remains in print.
Article
Developmental anomalies were scored and prevalences were computed for two skeletal collections from Devín (southwestern Slovakia). The first sample Devín-Hrad (DH) is dated to the Middle Ages (11th–12th century) and includes 217 skeletons. The second collection Devín-Za kostolom (FR) includes 112 burials and is dated to the Great Moravian period (9th century). In both samples, the evidence of spina bifida occulta occurred most frequently of all the defects examined (24% in DH, 23% in FR). Sacralization (8% in DH, 7% in FR) was more common than lumbarization (2% in DH, 0% in FR), and spondylolysis (7% in DH, 4% in FR) was relatively frequent in both samples. The other developmental defects occurred in only one or a few individuals and represented sporadic occurrences. Copyright © 2003 John Wiley & Sons, Ltd.
Article
Atlanto-occipital fusion may be symptomatic or asymptomatic in nature. The anomaly may be incidentally detected at autopsies or during routine cadaveric dissections. The fusion of the atlas with occipital bone may result in the compression of vertebral artery and first cervical nerve. A total of 55 dried occipital bones in the Department of Anatomy, Universiti Kebangsaan Malaysia (UKM) and Department of Anatomy, Universiti Malaya (UM) were included in the study. The presence of atlantooccipital fusion was closely observed and morphometric measurements were taken. Out of 55 dried occipital bones studied, we observed atlanto-occiptalization in two bones (3.63 %). A total of 53 occipital bones (96.37 %) did not exhibit any anomalous fusions. Out of the two anomalous atlanto-occiptal fusions, one was complete while the other had unilateral right-sided fusion of the atlas with the occipital bone. Atlanto-occipitalization may result in the compression of vertebral artery thereby influencing the blood flow to the brain. Atlanto-occipitalization may also result in compression of the first cervical nerve. The action of the postural muscles on the extensor surface may be affected as a result of this anomaly. The present article discusses the clinical implications of atlanto-occipitalization, which may be beneficial for neurosurgeons, neurologists and radiologists in day-to-day clinical practice (Fig. 3, Ref. 17).