Cartilage, Bone And Joints Of The Neck Flashcards
What is in the anterior of the neck?
Hyoid bone
Thyroid cartilage
Cricoid cartilage
Tracheal rings
What is in the posterior of the neck?
Cervical spine
What is unique about the hyoid bone?
Has no bony articulations and is stabilised by ligaments and muscles
Role of hyoid
Suspends larynx, so tracheal rings and cartilage depend on it. Supports the floor of the mouth.
Divisions of the hyoid bone
Upper and lower halves of the lesser and greater horns (cornua)
Also has a body which divides it into the upper and lower halves
How many ossification centres does the hyoid bone have?
4
Embryology of the hyoid bone
Upper half of body and lesser horn are derived from the 2nd branchial arch
Lower half of body and greater horn are derived from the 3rd branchial arch
General ossification rule
Whenever there is a bone with a body, that is usually the primary ossification centre will be
What attached to the hyoid?
Stylohyoid ligaments
Anterior muscles of the head and neck: tongue, pharynx and larynx, suprahyoid and infrahyoids
Role of cervical spine
Connects head or rest of body
Supports weight of head
What is clinical relevance of centre of gravity of head being more forward than the neck?
People faint forwards or fall asleep forwards
What are typical and atypical vertebra?
Typical vertebra share anatomical features (4)
Atypical vertebra do not share anatomical features with other bones
Distinguishing features of typical cervical vertebrae
Body - weight bearing part of spine
Transverse process and transverse foramen containing vertebral artery and sinovertebral nerve
Neural arch with lamina and pedicle
Vertebral arch
Articular facets - superior (facing backwards) and inferior (forwards) lined by hyaline cartilage
Bifid spinous processes due to strong attachment to nuchal ligament
Uncinate process
How many ossification centres do vertebra have?
3 - one in body and one on each side of the neural arch
Describe the atlas C1
Articulates with skull above forming atlanto-occipital joint (nodding yes movement)
Articles with axis below forming atlanto-axial joint (side to side no movement)
No body or spinous process
Widest cervical vertebra
Only 2 ossification centres - since there is no body
Body is fused with the dens of axis
Each neural arch is thick and strong to form a powerful lateral mass
Describe the axis C2
Strongest cervical vertebra
Has odontoid process/dens
Largest spinous process
Rugged lateral mass
4 ossification centres - extra at dens
Dens prevents horizontal displacement of atlas
Describe C7
Prominent spinous process and is not Bifid
Large transverse process - vertebral vein passes through instead of artery
Cervical spine fractures
Burst (Jefferson fracture) - head fall first on - fracture of atlas
Hangman’s - hyperextension of the head on neck - fracture on axis
Describe the structure of intervertebral discs
Nucleus pulposus in centre and annulus fibrosis on outside
Fibrocartilagenous joints
Thicker anteriorly and thinner posteriorly - wedge-shaped
Where is there no intervertebral joint?
Between C1 and C2, since there is no body between them.
What happens in a herniated disc?
Deterioration of the annulus fibrosis. When this happens the nucleus pulposus leaks out into the intervertebral foramen and compresses the nerve,
What is the role of facet joints?
To limit movement of the vertebral column and give it stability
What are the upper neck and lower neck facet /apophyseal joints?
Upper neck: atlanto-occipital joint (synovial) and atlanto-axial joint
Lower neck: joints between superior and inferior articular processes of the rest of the cervical spine (C3-C7)
What type of joint is the Atlanto-occipital joint?
Condyloid joint because the condylar of the occipital articulates with the superior articular facet of atlas
Synovial joint - has joint capsule, synovial fluid, synovial membrane, articular surfaces covered by hyaline cartilage
