Spinal Anatomy Final Flashcards
What is the radiological test for skeletal maturity?
The Risser sign, an indication of bone maturity in the iliac apophysis
What does the magnitude of scoliosis refer to?
The length and angle of the curve deviation on x-ray
What is often used to measure the magnitude of scoliosis?
The Cobb Method
What does location of scoliosis infer?
The location on the vertebral segment forming the apex of the curve deviation
What does direction of scoliosis refer to?
The side the convexity of the curve will bend toward
What does etiology of scoliosis mean?
The cause of the scoliosis
What is structural scoliosis?
A more radical form of scoliosis,
It may worsen,
Associated with structural deformities of the vertebra or intervertebral disc,
Frequently has a fixed angle of trunk rotation
What is nonstructural scoliosis?
A mild form of scoliosis,
Unlikely to worsen,
Not associated with structural deformities of the vertebra or intervertebral disc
Lacks a fixed angle of trunk rotation
What are some of the classifications of scoliosis based on etiology?
Congenital, neuromuscular, neurofibromatosis, nerve root irritation, idiopathic
What is the classification of scoliosis that is unique to the individual patient?
Idiopathic scoliosis
What does idiopathic scoliosis infer?
The scoliosis is unique to the individual, it has no known cause, unknown etiology
What is the incidence of idiopathic scoliosis in the population?
1% to 4% of the population
What is the age range for infantile idiopathic scoliosis?
From birth to 3 years old
What is the age range for juvenile idiopathic scoliosis?
From 3 years old to 10 years old
What is the age range for adolescent idiopathic scoliosis?
Over 10 years old
Identify the curve direction, location, gender bias and incidence of infantile idiopathic scoliosis
Left thoracic, male, less than 1% incidence
Identify the curve direction, location, gender bias and incidence of juvenile idiopathic scoliosis
Right thoracic, females over 6 years old, and 12% - 21% incidence
Identify the curve direction, location, gender bias and incidence of adolescent idiopathic scoliosis
Right thoracic or right thoracic and left lumbar, females, and 80% incidence
What is the genetic factor associated with adolescent idiopathic scoliosis?
An autosomal dominant factor that runs in families
What is the relationship between curve deviation, incidence, and curve worsening?
The greater the deviation, the lower the incidence, and the more likely to worsen
What is/are the characteristic(s) of occipitalization of C1
The atlas may be partially or completely fused to the occiput
What is another way of implying occipitalization of C1?
Atlas assimilation
What is the incidence of occipitalization of C1?
0.1% to 0.8%
When do the centers of ossification for the odontoid process first appear?
During the last trimester in utero
When do the bilateral ossification centers for the odontoid process fuse?
At or shortly after birth
What joint is formed between the odontoid process ossification centers and the centrum of C2?
The subdental synchondrosis
Ossification between the odontoid process and centrum joint of C2 first appears at what age?
4 years old
A joint between the odontoid process and centrum of C2 is last identified at what age?
7 years old
What is the name given to the condition in which the joint formed between the odontoid process and centrum of C2 persists beyond age 7?
Os odontoideum
What is the name given to the joint between the odontoid process and centrum of C2 which is still evident beyond age 7?
Persistent subdental synchondrosis
What is the name given to the joint formed between the tip of the dens and the odontoid process centers of ossification?
Tip of the dens synchondrosis
At what age will the tip of the dens center of ossification appear?
Sometime in early adolescence
At what age will the tip of the dens fuse with the odontoid process?
Before age 12
If the joint formed between the tip of the dens and odontoid process centers of ossification persists beyond age 12, what is the condition called?
Terminal ossicle
What is a basilar impression?
Persistence of the nonunion of the basilar and condylar parts of the chondrocranium such that the cartilage deforms due to the weight of the brain
What is a basilar invagination?
The upper cervical spine appears to be invaginated into the skull on x-ray analysis
What is the incidence of rib-related changes following dorsalization of C7?
From .5 to 2.5 percent of the population
Do patients typically present with symptoms specific for dorsalization of C7?
No, they are typically asymptomatic
What is the gender bias suggested in dorsalization of C7?
Female
What alteration in C7 facet orientation may accompany dorsalization?
The superior articular facet of C7 may change from back, upward, and medial (BUM) to that of a typical thoracic facet…back, upward, and lateral (BUL); the inferior articular facet is unchanged
What percent of the population may demonstrate thoracic-like features at C7?
Up to 46%
What T1 facet orientation changes may accompany cervicalization?
The superior articular facet may change from back, upward, and lateral (BUL) to back, upward, and medal (BUM); the inferior articular facet is unchanged
What is the incidence of cervicalization of T1 in the population?
Up to 28% of the population
What is the incidence of lumbar ribs in the population?
Over 7% of the population demonstrates lumbar ribs
What L1 facet orientation changes may accompany dorsalization?
The superior articular facet may change from concave, back, upward, and medial to flat, back, upward, and lateral; the inferior articular facet is unchanged
What is the gender bias associated with dorsalization of L1?
Males are two to three times more affected
What T12 facet orientation changes may accompany dorsalization?
The superior articular facet may change from flat, back, upward, and lateral to concave, back, upward, and medial; the inferior articular facet is unchanged
What T11 facet orientation changes may accompany lumbarization?
The inferior articular facet may change from flat, forward, medial, and downward to convex, forward, lateral, and downward; the superior articular facet is unchanged
What is the usual way of identifying the number of cervicals, thoracics and lumbar vertebrae during imaging studies?
Identify the vertebrae with ribs - they will be thoracics; those higher are cervicals, those lower are lumbars
What is characteristic of lumarization of S1?
The failure of synostosis between S1 and S2, squaring of the vertebral body of S1 and flaring of the sacral ala
What is failure of synostosis between S1 and S2?
The segments do not completely fuse together
What is squaring of the vertebral body of S1?
The S1 vertebral body has similar anterior and posterior heights, hence a lack of wedging
What is flaring of the sacral ala?
The transverse process of the ala appears to elevate as though separating from the rest of the sacral ala
What articular facet changes accompany lumarization of S1?
none
What is characteristic of sacralization of L5?
L5 may be partially or completely fused to the sacrum
What is the incidence of sacralization of L5 in the population?
41% to 85%
Which segment demonstrates the greatest morphological variation along the spine?
L5
What articular facet changes accompany sacralization of L5?
none
What is the incidence of variation within the sacrococcygeal region in the population?
Up to 14%
What is characteristic of sacralization of Co1?
The premature fusion of Co1 to the sacrum
What is characteristic of coccygealization of S5?
The separation of S5 from sacrum and its’ premature fusion to Co1
The trapezius is innervated by what nerve?
The spinal accessory nerve
What forms the spinal accessory nerve innervating the trapezius?
C1-C5 cord levels contribute to the spinal root of the spinal accessory nerve
The latissimus dorsi is innervated by what nerve?
The thoracodorsal nerve
What forms the thoracodorsal nerve innervating the latissimus dorsi?
Ventral rami from C6-C8
What forms the dorsal scapular nerve?
The ventral ramus of C5
What is the innervation of the splenius capitis?
Dorsal rami of middle cervical spinal nerves (C3-C5 cord levels)
Splenius cervicis will attach to what locations on the spine?
Lateral mass of C1 and posterior tubercle of transverse process on C1-C4
Which muscles are identified as erector spinae or sacrospinalis muscles?
Iliocostalis, Longissimus, Spinalis
What is the innervation of the iliocostalis lumborum?
Dorsal rami of lower thoracic and all lumber spinal nerves
What osseous parts of the vertebral column serve as an origin to the iliocostalis thoracis?
none
What is the insertion for the iliocostalis thoracis?
Costal angles of the upper 6-7 ribs, transverse process of C7
What osseous parts of the vertebral column serve as an origin to the longissimus thoracis?
Accessory process and transverse processes of L1-L5, spinous processes of L3-L5 and median sacral crest S1-S3
What is the innervation of the longissimus cervicis?
Dorsal rami of C4-C8 and T1-T2 spinal nerves (C4-C8 and T1-T2 cord levels)
What osseous parts of the vertebral column serve as an origin to the spinalis thoracis?
Spinous processes of T11 & T12 - L1 & L2
Which muscles are identified as transversospinalis muscles?
Semispinalis, multifidis and rotators
How many vertebrae can be attached to a single segment by transversospinalis muscles?
As many as 9 vertebrae
What segment will represent the lowest attachment site for the semispinalis thoracis?
T12
What osseous parts of the vertebral column serve as an origin to the semispinalis cervicis?
Transverse tubercles of T1-T5 or T6 & articular processes of C4-C7
What osseous parts of the vertebral column serve as an origin to the semispinalis capitis?
Transverse tubercles of C7, T1-T6 or T7 & articular processes of C4-C6
The semispinalis capitis and spinalis capitis may fuse to form what muscle?
Biventer cervicis
What osseous parts of the vertebral column serve as an origin to the classic multifidis?
Articular process of C4-C7, transverse processes of T1-T12, mammillary processes of L1-L5 and the dorsal surface of S1-S4 or S5
Contraction of the classic multifidis will result in what movements of the vertebral column?
Lateral flexion & rotation of the spine,
Maintains the lumbar lordotic curve,
Prevents entrapment of zygapophyseal capsular ligament during movement
Contraction of multifidis cervicis will result in what movements?
Alters the zygapophyseal capsular ligament response to load distribution,
Determines the cervical spine response to injury as evidenced by neck pain,
Is a significant contributor to postural control of the head and neck
Contraction of multifidis lumborum will result in what movements?
Lateral flexion & rotation of the lumbar spine,
Maintains the lumbar lordotic curve,
Prevents entrapment of lumbar zygapophyseal capsular ligament during movement
Which muscles of the spine exhibit a reversal of the expected origin - insertion combination?
Iliocostalis lumborum pars lumborum, longissimus thoracic pars lumborum and multifidis lumborum
Rotator muscles are typically identified in what region of the spine?
The thoracic region
Which suboccipital muscle lacks an attachment to the skull?
Obliquus capitis inferior
Which nerve will innervate all suboccipital muscles?
The dorsal ramus of C1, the suboccipital nerve
What is the origin of the obliquus capitis inferior?
C2 spinous process and lamina
An increase in the density of muscle spindles is most apparent in which suboccipital muscle?
Obliquus Capitis Inferior
What is the proposed function of the suboccipital muscle group?
Postural stabilizers of the atlanto-occipital and atlanto-axial joints
Which suboccipital muscles are known to attach to dura mater?
Rectus capitis posterior major, rectus capitis posterior minor & obliquus capitis inferior
Interspinalis is paired in which regions of the spine?
Cervical and lumbar regions
Based on the density of muscle spindles what is the proposed function of the interspinalis?
Acts as a proprioceptive transducer in conjunction with intertransversarii to coordinate the smooth movement of the spine and to maintain appropriate posture
What is the origin of the longus colli?
Vertebral bodies of C5-C7, T1-T3 & anterior tubercles of transverse processes C3-C5
What is the origin of the rectus capitis anterior?
Lateral mass & costal element of the transverse process of C1
What will innervate the rectus capitis anterior?
Ventral rami of C1-C2 spinal nerves
What will innervate the rectus capitis lateralis?
Ventral rami of C1-C2 spinal nerves
What is the insertion of the anterior scalene?
Ridge and anterior scalene tubercle of the first rib
What is the insertion of the middle scalene?
Between the tubercle and groove for the subclavian artery on the first rib
What is the insertion of the posterior scalene?
Outer surface of second rib
What will innervate the posterior scalene?
Ventral rami of C6-C8 spinal nerves
The quadratus lumborum is implicated in the formation of which ligaments?
The iliolumbar ligament
What is the origin of the psoas major?
Vertebral bodies T12, L1-L5, S1 and transverse processes of L1-L5
What is the origin of the psoas minor?
Vertebral bodies T12, L1
What will innervate the psoas minor?
Ventral ramus of L1 spinal nerve
What is the maximum number of common ligaments identified with a vertebral couple?
8
What is the reason that 9 common ligaments are identified but only 8 will be attached at any specific vertebral couple?
The ligamentum nuchae and supraspinous ligaments attach to the spinous tubercles, but only 1 of these will be identified at a single vertebral couple
What is the number of true intervertebral discs identified in the adult?
23
In the adult, which vertebral levels will demonstrate a true intervertebral disc?
Those between C2 and S1 inclusive
What is the percent of intervertebral disc height contribution to the length of each region of the vertebral column?
Cervical: 22-25% Thoracic: 20% Lumbar: 33%
What are the names of the central, peripheral, and horizontal zones of the intervertebral disc?
Nucleus pulposus - central zone
Annulus fibrosus - peripheral zone
Cartilaginous end plate - horizontal zone
What is the water concentration in the lumbar nucleus pulposus at birth and after thirty?
Birth - 88% Thirty - 70%
What is the consequence of non-aggregated glycosaminoglycans in the lumbar nucleus pulposus?
The nucleus pulposus will loose water under deformation conditions
What cell is associated with the nucleus pulposus until about age 11?
Notochord cells
Which type of collagen is dominant in the nucleus pulposus?
Collagen type II
What is the organizational pattern for collagen fibers in the nucleus pulposus?
They are irregularly oriented and randomly scattered
What is the appearance of the cervical annulus fibrosus?
A horse-shoe with the anterior margin thick and the lateral margins tapering to the uncinate process; the posterior margin is thin
What compensates for the thinness of the posterior part of the cervical annulus fibrosus?
Posterior longitudinal ligament
What is the organization of the lumbar annulus fibrosus?
It has 12-14 concentric cylindrical lamellae
What is the water concentration in the lumbar annulus fibrosus at birth and after 30?
Birth - 78% Thirty - 70%
What is the organizational pattern for glycosaminoglycans in the lumbar annulus fibrosus?
They typically have a binding site for hyaluronic acid ad are thus aggregated
Which type of collagen is dominant the annulus fibrosus?
Collagen type 1
What is the organizational pattern for collagen fibers in the annulus fibrosus?
They are parallel with one another in a single lamellus and angled
What is the organization of collagen fibers between lamellae?
Collagen fibers will be angled in the opposite direction such that a spiral - counter spiral organization is observed
What is the attachment site for collagen fibers within the annulus fibrosus?
Collagen fibers of the outer lamellae will become Sharpey’s fibers and penetrate the epiphyseal rims Collagen fibers of the inner lamellae will attach to the cartilaginous end plate
What is the origin for the cells of the annulus fibrosus?
Sclerotomites
What is the principal type of collagen fiber within the cartilage end plate?
The type II collagen fiber
What is the direction of collagen fibers within the cartilage end plate?
Collagen fibers are aligned anterior to posterior
What is the attachment site for collagen fibers of the inner lamellae of the annulus fibrosus?
The cartilaginous end plate
What are the types of receptor endings in the intervertebral disc?
Nociceptors and proprioceptors
What is the relationship between size of the intervertebral disc and receptor endings?
The larger the disc, the greater the variety of receptor endings
What part of the intervertebral disc is innervated by the recurrent meningeal/sinu-vertebral/sinus vertebral nerve?
The outer lamellae of the annulus fibrosus at the posterior part of the intervertebral disc
What forms the anterior neural plexus of the vertebral column?
Fibers from the ventral primary ramus
What forms the lateral neural plexus of the vertebral column?
Fibers from the ventral primary ramus,
Fibers from the white ramus communicans,
Fibers from the gray ramus communicans
Fibers from the paradiscal ramus communicans,
What is the name given to the white ramus communicans which becomes embedded within the annulus fibrosus of the intervertebral disc?
The paradiscal ramus communicans
What part of the intervertebral disc is innervated by fibers from the paradiscal ramus communicans?
The outer lamellae of the annulus fibrosus at the lateral part of the intervertebral disc
How does the intervertebral disc attach to the vertebral body?
Sharpey’s fibers from the outer lamellae of the annulus fibrosus are firmly embedded into the epiphyseal rims of the adjacent vertebral bodies
Based on histology, what is the classification of the intervertebral disc?
A cartilaginous (amphiarthrosis) symphysis
What are the divisions of the embryonic somite?
The sclerotome, myotome, and dermatome
What structure is formed following migration of sclerotomes to surround the notochord?
The perichordal blastema
What is formed within the perichordal blastema between the sclerotomites?
The intrasclerotomal fissure or fissure of von Ebner
What does the intrasclerotomal fissure or fissure of von Ebner become?
The perichordal disc
What will the dense sclerotomite become?
The upper part of the vertebral segment forming below
What structure forms following migration and subsequent mixing of the sclerotomites?
The vertebral blastema
What part of the intervertebral disc will the notochord form?
The nucleus pulposus
What part of the intervertebral disc will the perichordal disc form?
The annulus fibrosus
What is the earliest indicator of the position of the adult intervertebral disc?
The intrasclerotomal fissure or fissure of von Ebner
What vertebral levels will the anterior longitudinal ligament attach to?
Those between occiput and S3 inclusive are traditionally indicated
What is the lowest extent of the anterior longitudinal ligament based on recent studies?
L3
What is believed to form the anterior longitudinal ligament in the lumbar spine?
The tendon of the crura of the diaphragm
What innervates the anterior longitudinal ligament?
The anterior neural plexus formed by fibers from the ventral primary ramus and sympathetic postganglionic fibers from the paravertebral ganglia
What is the function of the anterior longitudinal ligament?
It brakes or limits dorsiflexion or hyperextension of the vertebral column
What was ossification of the anterior longitudinal ligament in the lumbar region identified as?
Forestier’s Disease
What is ossification of the anterior longitudinal ligament in the lumbar region now identified as?
Diffuse Idiopathic Skeletal Hyperostosis or DISH
Newer research suggests what regional variation in the posterior longitudinal ligaments?
Prominent in the cervicals, occasional in the thoracics, rare in the lumbars
What is the relationship of the posterior longitudinal ligament to the vertebral foramen?
It forms the anterior boundary of the spinal canal
What is the innermost layer of the posterior longitudinal ligament called?
The perivertebral ligament
What is the function of the posterior longitudinal ligament?
It brakes or limits flexion of the vertebral column
Where is ossification of the posterior longitudinal ligament most commonly identified?
The cervical spine with an 80% incidence
What is the clinical sign of posterior longitudinal ligament ossification in the cervical spine?
A loss of hand and finger dexterity
What is the clinical sign of posterior longitudinal ligament ossification in the lumbar spine?
Faltering gait
What is the gender, age, and ethnic bias associated with ossification of the posterior longitudinal ligament?
It is greater in males over 50 and has a higher incidence in the Japanese
What is the name given to the ligamentum flavum based on appearance and histology?
It is a yellow elastic ligament
What fibers are most ligaments made up of?
Collagen type I fibers with are whitish in appearance
Where is ossification of the ligamentum flavum most commonly identified?
The thoracic spine or thoracolumbar transition zone
What is the relationship between the capsular ligament and mobility?
The more lax/loose the capsular ligament is, the greater the motion of the joint
What regions of the vertebral column demonstrate the greatest laxity of capsular ligaments?
The cervical and lumbar regions
What layers are present in the capsular ligament?
A superficial layer of collagen fibers and a deep layer of elastic fibers
If the zygapophyseal capsular ligament is not significantly involved in restricting motion what is its’ function?
It is probably involved in proprioceptive feedback to the muscles stabilizing the vertebral couple during movement
What is now thought to be a major function of the interspinous ligament?
It is more likely a proprioceptive transducer for the spinal reflex
What is the name given to the superficial layer of the ligamentum nuchae?
The funicular layer or part
What is the name given to the deep layer of the ligamentum nuchae?
The lamellar layer or part
What are the attachment sites for the superficial layer of the ligamentum nuchae?
The external occipital protuberance, the external occipital crest, and spinous tubercle of C7
What is the histological make-up of the human ligamentum nuchae?
It is a yellow elastic ligament, but has more collagen fibers than in quadrupeds
What is the classic function of the human ligamentum nuchae?
It brakes or limits flexion of the cervical spine
What is the termination level inferiorly for the supraspinous ligament according to current literature?
Primarily at L4 (73%); between L4 and L5 (5%)
What is now thought to be a major function of the supraspinous ligament?
It is a proprioceptive transducer for the spinal reflex
What amount of flexion-extension is accommodated by the atlanto-occipital joint?
About 25 degrees
What amount of axial rotation is accommodated by the atlanto-occipital joint?
About 3-8 degrees one side axial rotation
What amount of lateral bending is accommodated by the atlanto-occipital joint?
About 5 degrees
What motion is best accommodated by the atlanto-occipital joint?
Flexion-extension
What is the function of the transverse atlantal ligament?
It is the primary stabilizer of the atlanto-axial joint restricting the distance of C2 from the anterior arch of C1
What movements are facilitated at the median atlanto-axial joint?
Flexion-extension, rotation, and telescoping (superior-inferior gliding)
***What is the ADI?
The Atlanto-Dental Interspace, a radiographic distance between the surfaces of the anterior bursa of the median atlanto-axial joint
***What is the ADI of children compared with that of adults?
About 4.5 mm in children; a range of 2-3 mm or about 2.5 mm in adults
What are the degrees of movement facilitated at the atlanto-axial joint?
About 20 degrees flexion-extension,
40 degrees one side axial rotation,
5 degrees of lateral bending
The occiput-C1-C2 joint complex accounts for what percent of all cervical axial rotation?
About 60%
What is the embryonic derivative of the apical ligament of the dens or the apicodental ligament?
The notochord
What is the function of the alar ligament?
Together they function to resist axial rotation
What forms the cranial continuation of the posterior longitudinal ligament?
The membrana tectoria or tectorial membrane
List, in order, the ligaments in a midsagittal plane from the dura mater at the level of the medulla oblongata to the anterior bursa of the median atlanto-axial joint.
The membrana tectoria or tectorial membrane
The cruciate ligament
The capsular ligament of the posterior bursa of the median atlanto-axial joint
The apical ligament of the dens or the apicodental ligament
For the cervical spine below C2, what is the range of flexion-extension?
About 90 degrees or about 18 degrees per couple
For the cervical spine below C2, what is the range of one side lateral bending?
About 50 degrees or about 10 degrees per couple
For the cervical spine below C2, what is the range of one side axial rotation?
About 33 degrees or about 6 degrees per couple
What are the locations for the costovertebral joints on the vertebra?
The costocentral joint at the vertebral body and the costotransverse joint at the transverse process
At what rib will the superior costotransverse ligament be absent?
The 1st rib
What ligaments will attach to the neck of the 12th rib?
The superior costotransverse ligament from T11 and the lumbocostal ligament from L1
What are the attachment sites for the inferior costotransverse ligament?
The neck of the rib and the transverse process of the vertebra at the level
At what rib will the inferior costotransverse ligament be absent?
The 12th rib
What is the name of the space between the transverse process and the neck of the rib?
The costotransverse foramen
Which ligament ‘fills’ the costotransverse foramen?
The inferior costotransverse ligament
What are the attachment sites for the lateral costotransverse ligament?
The non-articular surface of the tubercle of the rib and the transverse tubercle of the transverse process of the vertebra at that level
Which vertebra will lack an attachment for the lateral costotransverse ligament?
T12
Which vertebral couples of the thoracic spine have the greatest motion?
T11/T12 and T12/L1
Which range of motion is the greatest for lower thoracic vertebral couples?
Flexion-extension
Which range of motion is least for lower thoracic vertebral couples?
One side axial rotation
Which ligaments replace the intertransverse ligament at the lumbosacral joint?
The iliolumbar ligament and lumbosacral ligament
What muscle is intimately attached to the superior iliolumbar ligament?
Quadratus lumborum
Which of the current ligaments from the iliolumbar ligament complex represents the iliolumbar ligament of classical descriptions?
The superior iliolumbar ligament
Which ligament from the iliolumbar ligament complex will attach to the sacral ala?
The inferior iliolumbar ligament
Which ligament from the iliolumbar ligament complex represents the lumbosacral ligament of classical descriptions?
The inferior iliolumbar ligament
What are the attachment sites for the accessory iliolumbar ligament?
The transverse process of L4 and the iliac crest
Which vertebral couple of the lumbar spine has the greatest range of motion?
L5/S1
Which range of motion is greatest for all lumbar vertebral couples?
Flexion-extension
Which range of motion is least for L1-L5 vertebral couples?
One side axial rotation
Which range of motion is least for the L5/S1 vertebral couple?
One side lateral bending
List, in order, from cranial to caudal the ligaments forming the anterior boundary of the spinal canal.
The membrana tectoria, posterior longitudinal ligament and the deep posterior sacrococcygeal ligament
List, in order, from cranial to caudal the ligaments forming the posterior boundary of the spinal canal.
The posterior atlanto-occipital ligament, posterior atlanto-axial ligament, ligamentum flavum and the superficial posterior sacrococcygeal ligament
What is the auricular surface of the ilium composed of?
Articular cartilage, interspersed with fibrocartilage
What does ankylosis mean?
A condition of fibrous adhesion occurs within the joint
What is the age and surface bias associated with degenerative arthrosis of the sacro-iliac joint?
Age 40, the iliac auricular surface
What is the age and gender bias associated with ankylosis of the sacro-iliac joint?
Age 50 and male bias particularly in African American males
What passes between the layers of the interosseous sacroiliac ligament?
Dorsal rami from the sacral spinal nerves
What separates the manubrium sterni and corpus sterni?
The manubriosternal symphysis
What vertebral levels corresponds to the position of the corpus sterni?
T5-T9
How many sternabrae for the corpus sterni?
4 sternabrae
What surface feature on the corpus sterni identifies the location of the synchondroses?
Transverse lines
What articular sites for the costal cartilage of ribs will be identified on the corpus sterni?
Costal notches II-VII
What feature of the corpus sterni is present in 4-7% of the population?
A sternal foramen
What causes the appearance of the sternal foramen?
Failure of the ossification centers of the sternum to fuse together normally
What attaches to the scalene tubercle of the first rib?
The anterior scalene muscle
Which groove on the body (corpus or shaft) of the first rib is close to the vertebral end?
The groove for the subclavian artery and the first thoracic nerve
Which groove on the body (corpus or shaft) of the first rib is close to the sternal end?
The groove for the subclavian vein
What specifically will attach to the crest of the neck of the second rib?
The superior costotransverse ligament from the transverse process of T1
What specifically attaches to the back of the neck of the second rib?
The inferior costotransverse ligament from the transverse process of T2
What unique feature is present on the body (corpus or shaft) of the second rib?
The tuberosity for the serratus anterior
Which ribs are classified as typical ribs, true ribs, costa verae, and vertebrosternal ribs in the adult skeleton ?
Ribs 3-7
Which ribs are classified as atypical ribs, true ribs, costa verae, and vertebrosternal ribs in the adult skeleton ?
Ribs 1 and 2
Which ribs are classified as typical ribs, false ribs, costa spuriae, and vertebrochondral ribs in the adult skeleton ?
Ribs 8 and 9
Which ribs are classified as atypical ribs, false ribs, costa spuriae, and vertebrochondral ribs in the adult skeleton ?
Rib 10
Which ribs are classified as atypical ribs, false ribs, costa spuriae, and vertebral ribs in the adult skeleton ?
Ribs 11 and 12
What is the classification of the 1st sternocostal or sternochondral joint?
Cartilaginous (amphiarthrosis) synchondrosis
What is the classification of the 2nd-7th sternocostal or sternochondral joint?
Synovial plane (diarthrosis arthrodia)
Which of the sternocostal or sternochondral ligaments is unique to the 2nd sternocostal or sternochondral joint?
The intra-articular ligament
What is the classification of the 6th-9th interchondral joints?
Synovial plane (diarthrosis arthrodia)
What is the classification of the 5th-6th or 9th-10th interchondral joints?
Fibrous (amphiarthrosis) syndesmosis
Which costal cartilages fail to form a joint at their sternal end?
The eleventh and twelfth costal cartilages
How many primary centers of ossification appear in the manubrium?
1-3 centers have been identified
How many primary centers of ossification appear in the corpus sterni?
Typically 6
In what part of the sternum will a secondary center of ossification appear?
The xiphoid process
In what part of the rib will primary centers of ossification appear?
The body (corpus,shaft)
In what parts of the rib will secondary centers of ossification appear?
The head, articular surface of the tubercle and the non-articular surface of the tubercle
Which ribs will demonstrate secondary centers of ossification?
Ribs 1-10
Which ribs lack secondary centers of ossification?
Ribs 11 and 12
Which ribs demonstrate three secondary centers of ossification?
Ribs 2-9
Which ribs have only two secondary centers of ossification?
Ribs 1 and 10
What are the four subclassifications of synarthrosis joints based on Latin groupings?
Suture, gomphosis, schindylesis and syndesmosis
What were the five types of suture based on Latin groupings?
Serrate, denticulate, limbous, squamous and harmonia
What are the characteristics of sutura vera (true sutures)?
Sutures demonstrating interlocking of the adjacent bone surfaces; typically formed by intramembranous ossification
What are the characteristics of sutura notha (false sutures)?
Sutures lacking interlocking of adjacent bone surfaces; typically formed by endochondral ossification
Which sutures demonstrate non-interlock, but will overlap at their edges?
Squamous sutures
What were the classification of sutura notha (false sutures) based on Latin groupings?
Squamous and harmonia
What are the typical examples of the plane suture or harmonia suture?
Cruciate suture made up of the intermaxillary, interpalatine and palato-maxillary sutures
What are the examples of the schindylesis type of suture?
Sphenoid-ethmoid-vomer articulation, the palatine-maxilla-vomer articulation
What are the examples of the gomphosis joint?
Maxilla-root of tooth; Mandible-root of tooth
What are the five views of the skull called?
Norma verticalis, norma frontalis, norma occipitalis, normal lateralis, norma basalis
What is the diamond shaped remnant of developing membrane bone at the intersection of the frontal bone with both parietal bones?
The anterior fontanelle
What is the diamond shaped remnant of developing membrane bone at the intersection of the occipital bone with both parietal bones?
The posterior fontanelle
What is the glabella?
The elevation of bone over the frontal sinus between the orbits
What is the name given to the outline of the nasal cavity at the front of the skull?
Piriform aperture
What is the name given to the alveolar jugum of the canine tooth in the maxilla?
Canine eminence
What forms a bullet-like chin?
A large mental protuberance
What forms an indented chin?
Well developed bilateral mental tubercles and a slight mental protuberance
What bones form the pterion?
Parietal, temporal, sphenoid and frontal bones
What points on the skull are used to measure the skull size?
The nasion, vertex, inion and gnathion
What points on the skull are used to measure cranial vault capacity?
The nasion, vertex and inion
The olfactory nerve exits the cranial vault via what opening?
Cribriform plate of the ethmoid bone
What are the contents of the optic canal?
The optic nerve and ophthalmic artery
What are the contents of the superior orbital fissure?
Ophthalmic veins,
Ophthalmic division of the trigeminal nerve,
Oculomotor nerve,
Trochlear nerve,
Abducent nerve
What are the contents of the foramen rotundum?
The maxillary division of the trigeminal nerve (cranial nerve Vb)
What are the contents of the foramen ovale?
The mandibular division of the trigeminal nerve (Vc) and the lesser petrosal branch of the glossopharyngeal nerve
What are the contents of the foramen spinosum?
The nervus spinosus from the mandibular division of the trigeminal nerve and the middle meningeal artery
What are the contents of the internal acoustic meatus?
Cranial nerves VII (facial nerve) and VIII (vestibulocochlear/auditory nerve),
The nervus intermedius/nerve of Wrisberg/sensory root of VII and the motor root of VII,
The vestibular and cochlear roots of VIII,
The internal auditory/internal labyrinthine artery and vein
What are the contents of the jugular foramen?
The jugular bulb,
The inferior petrosal sinus,
The tympanic body/tympanic glomus or jugular body/jugular glomus,
Cranial nerves IX (glossopharyngeal), X (vagus) and XI (spinal accessory)
What can the five layers of the scalp spell?
Skin, connective tissue, aponeurosis, loose connective tissue, periosteum…SCALP
What are the principal sources of blood to the scalp?
Internal carotid and external carotid artery branches
Which divisions of the trigeminal nerve receive sensory information from the scalp?
All 3 divisions: ophthalmic nerve, maxillary nerve, & mandibular nerve
Which ventral rami branches supply the scalp?
Greater auricular and lesser occipital nerves
Which dorsal ramus nerve branch (name and cord level of origin) supplies the scalp?
Greater occipital nerve - C2, C3 communicating ramus
What forms the roof of the posterior cranial fossa?
The tentorium cerebelli
What part of the cerebrum occupies the posterior cranial fossa?
None; the tentorium cerebelli separates the cerebrum into a space above the posterior cranial fossa
What part of the central nerve system occupies the posterior cranial fossa?
The cerebellum, pons, and medulla oblongata
Which muscles lack any attachment to bone?
Orbicularis oris, procerus & risorius
What type of motor fibers to skeletal muscle are given off by the facial nerve?
Branchial efferent (BE)
Most of the seventh cranial nerve will exit the skull via what opening?
The stylomastoid foramen
The optic canal is located along which wall of the orbit?
Superior wall of the orbit
What are the contents of the optic canal?
Optic nerve & ophthalmic artery
What are the openings located along the medial wall of the orbit?
Anterior ethmoid & posterior ethmoid foramina
What is the name given to the medial wall of the orbit?
Lamina papyracea
The superior orbital fissure is located along which wall of the orbit?
Lateral wall of the orbit
What are the contents of the superior orbital fissure?
Oculomotor nerve
Trochlear nerve
Abducent/abducens nerve
Ophthalmic division of the trigeminal cranial nerve
Ophthalmic veins
What opening(s) are located along the inferior wall of the orbit?
Inferior orbital fissure
What is contained in the inferior orbital fissure?
Maxillary division of trigeminal nerve
What are the names given to the modified sebaceous gland in the tarsus of the eyelid?
Tarsal or Meibomian gland
What specific pathways are identified with Visceral Efferent (VE) innervation?
Sympathetic and parasympathetic motor pathways
How many neurons are involved in the Visceral Efferent pathways from CNS to target cell?
2 motor neurons
What is the location for the second neuron in the Visceral Efferent (VE) pathway?
Typically a ganglion
Which cranial nerves are involved in the Visceral Efferent (VE) parasympathetic pathway to the lacrimal gland?
Facial and trigeminal (maxillary and ophthalmic divisions/branches)
What is the origin for the sympathetic pathway to the lacrimal gland?
Lateral horn/intermediolateral cell column T1,T2
What is the target of the preganglionic sympathetic visceral efferent (VE) fiber in the pathway to the lacrimal gland?
The VE fiber ascends to the superior cervical ganglion to synapse
****Sympathetic stimulation of the lacrimal gland will result in what events?
Vasoconstriction of blood vessels,
Limited availability of water to secretory units,
More viscous or thicker product formed in glandular lumen
****Parasympathetic stimulation of targets in the lacrimal gland will result in what events?
Vasodilation of blood vessels,
Increased availability of water to secretory units,
Thinner or more watery product in lumen;
Constriction of myoepithelial cells leading to release of product from secretory lumen into duct system
What are the names of layers of the eyeball?
Fibrous tunic, uveal tract and retina
What are the parts of fibrous tunic of the eyeball?
Cornea and sclera
What are the parts of the uveal tract of the eyeball?
Iris, ciliary body, choroid & pupil
What muscles are present in the iris?
Sphincter pupillae and dilator pupillae
What is the innervation of the sphincter pupillae?
Oculomotor nerve, parasympathetic pathway
What is the innervation of the ciliaris muscle?
Oculomotor nerve, parasympathetic pathway
What is the function of the rod cell?
Provide vision in dim light conditions
What is the function of the cone cell?
Provide vision in bright light conditions and mediate color vision
What is the most numerous photoreceptor cell?
Rod cell
What forms the optic nerve?
Axons of ganglion cells
What occurs at the optic chiasma?
Part of the optic nerve decussates
What is the location of the anterior chamber of the eyeball?
Between the cornea and iris
What is the location of the posterior chamber of the eyeball?
Between the iris and lens
What is contained in the anterior chamber of the eyeball?
Aqueous humor
What is contained in the posterior chamber of the eyeball?
Aqueous humor
What is the name given to the chamber behind the lens?
Vitreous chamber
What fills the vitreous chamber?
Vitreous body
What are the common characteristics in origin and insertion of all rectus extraocular muscles?
They all originate from a common annular tendon in the orbit
They all insert in the sclera in front of the coronal equator of the eyeball
What is the common characteristic regarding the insertion of both oblique extraocular muscles?
Both insert onto sclera on the lateral margin of the eyeball behind the coronal equator
What is the common characteristic concerning the insertion of the superior and inferior rectus muscles?
They insert onto the sclera of the eyeball in front of the coronal equator and are displaced slightly medially
What is the embryonic origin of the extraocular muscles or extrinsic muscles of the eyeball?
The skeletal muscle is derived from the somites hence somatic efferent (SE)
Which nerves will innervate specific extrinsic/extraocular muscles?
Oculomotor - superior rectus, medial rectus, inferior rectus, inferior oblique
Trochlear - superior oblique
Abducens/Abducent - lateral rectus
Which of the cranial nuclei of termination contain primary afferent neurons?
Mesencephalic nucleus of the trigeminal nerve
What is the location of synapse for preganglionic parasympathetic efferent fibers of the third cranial nerve?
Ciliary ganglion
What is unique about the vascular supply of the retina?
A single vessel supplies it
What vessel supplies the inner tunic of the eyeball?
Central artery of the retina
What is the name given to the “goat’s beard” of the auricle?
Tragus
What is the name of the palpable posterior projection of the eminentia concha of the auricle?
Ponticulus
Which cranial nerve will innervate the muscles of the auricle?
The facial nerve
Sensory innervation of the auricle is derived from which nerves?
Greater auricular (ventral rami C2,C3)
Lesser occipital nerve (ventral rami C2, possibly C3)
Auriculotemporal nerve (mandibular division, trigeminal)
Posterior auricular cutaneous nerve (facial)
Auricular nerve (vagus)
The lateral third of the external acoustic meatus is protected by ____?
Cartilage
The medial third of the external acoustic meatus is protected by ____?
The temporal bone
Skin lining the external acoustic meatus contains what modified sebaceous glands?
Ceruminous glands
What is cerumen?
The product of ceruminous glands forming the bulk of ear wax
What are the characteristics of the parotid gland?
It is lobulated, yellowish, encapsulated and an exocrine gland
What vein is formed within the parotid gland?
The retromandibular vein
Within the parotid gland what does the facial nerve form?
The facial nerve plexus
What are the branches of the facial nerve plexus?
Temporal, zygomatic, buccal, marginal mandibular, and cervical branches
What branch of the facial nerve penetrates the parotid gland, but is not given off within it?
The chorda tympani nerve
Which of the cervical intertransversarii is innervated by dorsal rami of cervical spinal nerve?
Posterior medial belly, cervical intertransversarii
What is the origin of the medial belly of the lumbar intertransversarii?
Accessory process of transverse proccess L1-L4
Mammillary process of superior articular process L1-L4
Which muscle group is innervated by both dorsal rami and ventral rami of spinal nerves?
Intertransversarii
Based on the density of muscle spindles what is the proposed function of the intertransversarii?
Acts as a proprioceptive transducer in conjuction with interspinalis to coordinate the smooth movement of the spine and to maintain appropriate posture
