Day 40 (Ligamentum Flavum, Capsular ligament, interspinous ligament, ligamentum nuchae, supraspinous ligament, atlanto-occipital joint, atlanto-axial joint) Flashcards
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 which 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, external occipital crest, and spinous tubercle of C7
What is the histological make-up of the human ligamentum nuchae?
it is 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 twenty-five degrees
What amount of axial rotation is accommodated by the atlanto-occipital joint?
about three to eight degrees one side axial rotation
What amount of lateral bending is accommodated by the atlanto-occipital joint?
about five degrees
Which 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 degres one side axial rotation, and 5 degrees of lateral bending
The occiput-C1-C2 joint complex accounts for what percent of all cervical axial rotation?
about 60%
