Articulation of Bones & Bony Features Flashcards
What bones does the occiput articulate with?
PARIETALS
TEMPORALS
SPHENOID
Parietals at lambdoid suture
Temporals at mastoid potions and petrous portions
Sphenoid - basilar portion of occiput articulates with sphenoid at SBS
SBS is PIVOTAL FULCRUM ROUND WHICH THE WHOLE BONY STRUCTURES OPERATE IN THE CS SYSTEM.
Name some features of the occipital bone?
Squamous portions
Occipital condyles x 2
Basi-occiput
External occipital protuberance (inion) - the trapezius muscle attaches here.
Internal occipital protuberance - the falx c and falx c and tentorium AND venous sinus pathways ALL COME TOGETHER at the Internal Occipital Protuberance to form the CONFLUENCE SINUSES.
Forms the Foramen Magnum with the Sphenoid body at the SBS
Sutures - Occipito- Mastoid - Jugular Foramen
Sinuses - occipital, running down the occipital border of the falx cerebri and transverse sinuses passes along occipital border of tentorium.
Membranes - tentorium has it’s attachment at the internal occipital protuberance and projects forward - runs along the petrous portion of the temporal bone
POSTERIOR CRANIAL FOSSA
New-born - in 4 parts -(Basi-occiput/2 condylar portions and squamous portion) prone to compression through forces exerted through buttocks of baby. Foramen magnum may become distorted = impingement of spinal cord.
What is the purpose of the sub-occipital release?
To address restrictions at the sub-occiput, where occiput meets atlas (C1) and is held by 4 small muscles.
These 4 muscles tilt the head back into extension, assist with rotating the head and stabilise the skull on C1 and C2.
What is the occipital CS rhythm?
LONGITUDINAL MOTION - Flexion -
occiput tucks under towards neck;
basilar portion moves anteriorly and superiorly as SBS moves into flexion.
LATERAL MOTION - Flexion
occipital region widens round midline, so moves at squamous portions
Where does the sacrum have membranous attachments?
S2 anteriorly and Coccygeal 1 posteriorly.
What are the articulations of the sacrum?
L5
Laterally with wings of iliac bones of pelvis forming 2 SI joints
coccyx
What is the CS motion of the Sacrum?
Flexion - apex of sacrum moves anteriorly - rocks forward
Extension - apex of sacrum moves posteriorly - rocks back
Midline structure
Name 5 ASYMMETRIES of Sacrum and explain
1) Side-bending - base of sacrum pulling to SI joint on one side.
2) Torsion - sacrum twisting posteriorly on one side
3) Side-shift - whole sacrum shunted to one side
4) Flexion - apex moving more strongly anteriorly
5) Extension - apex moving more strongly posteriorly
What is the role of the temporals?
House organs for hearing and balance
What do you associate with the temporals?
Emotional nature of the person with specific conditions eg LD; epilepsy; autism; recurrent ear infections; balance or hearing issues.
What does each temporal bone consist of? (8 examples)
1) Squamous portion - level with tops of ears
2) Mastoid portion
3) Mastoid processes - bony lump for attachment to SCM muscles
4) Styloid process - attaches to SCM muscle and ligament - Behind Styloid process is Styloid Mastoid Foramen = exit for Facial Nerve
5) External Auditory Maetus (ear hole) - opening into external auditory canal - sound waves pass through to tympanic membrane.
6) Mandibular Fossa - receives condyle from mandible to form TMJ (in front of external auditory meatus)
7) Zygomatic process - projecting bone from mandibular fossa to form zygomatic arch.
8) Temporal Fossa to attach to the Temporalis muscle
9) INTERNAL PETROUS PORTION - organs of hearing and balance are contained in petrous portion.
10) Sutures -
a) Squamosal suture - bevelled - temporals overlap the parietals - can get wedged.
b) Occipto-mastoid sutures - with connection to JF and structures - can become restricted - affects venous drainage and
11) Eustachian tube - originates at petrous portion of temporal and passes through petrous portion and greater wing of sphenoid, runs along spheno-temporal suture. Opens in external rotation
12) Membranes - Tentorium along petrous portion
13) Sinuses - Sigmoid - S shaped twists along grooves in petrous portions towards jugular foramina
MIDDLE CRANIAL FOSSA = petrous portions; SBS; spheno-temporal suture; OM suture
POSTERIOR CRANIAL FOSSA = petrous ridge; OM suture(
14 ) Internal acoustic meatus - canal - vestibulocochlear and facial nerve.
Which other bones do the temporal bones articulate with?
Parietal - along squamosal suture
Occiput - along occipito mastoid suture
Sphenoid - at spheno-temporal suture
Temporal FOSSA = 4 bones (above plus frontal)
Pterion = meeting point of temporal; sphenoid; parietal and frontal or Antero-Lateral Fontenelle
What membranes do the temporal bone attach with>
Tentorium cerebelli along PETROUS RIDGE
What is the CS motion of the temporal bone?
Flexion -
Temporals open out into external rotation with mastoid portions moving medially. Creates a wobbly wheel movement. External rotation opens Eustachian tube. Medially compressed mastoid portions affect venous drainage.
What is the axis for the external rotation of the temporal bone (wobbly wheel motion?)
Petrous ridge
What happens to the tentorium during the flexion phase of CS motion?
It flattens as it stretches laterally which affects the whole reciprocal tension membrane system. Also opens the straight sinus.
Where do the 2 parietal bones meet?
At the sagittal suture
What other bones do the parietals articulate with?
Frontal bone - at coronal suture
Occipital bone - at lambdoid suture
2 temporal bones at squamosal sutures
Greater wings of sphenoid - at pterions
What membranous attachments do the parietals receive?
Falx cerebri - either side of sagittal suture along midline
Tentorium - small attachment
Describe the CS motion of the parietals?
Flexion - 2 parietals flare - hinged around sagittal suture.
FALX CEREBRI acts as a fulcrum for rhythmic motion of parietals.
Which suture is bevelled?
squamosal suture - with temporals overlapping parietals.
Are sutures more often interdigitated or bevelled?
Interdigitated.
What is significant about the sphenoid bone>
Central, pivotal bone in the cranium and CS system
Fulcrum of the craniosacral system
Articulates with all bones of cranium
What is significant about the sphenoid bone and where is it located?
Central, pivotal bone in the cranium and CS system
Articulates with every other cranial bone and some facial bones - zygomatic, ethmoid, vomer and palatines.
The sella turcica in sphenoid body houses pituitary gland (endocrine gland) which releases hormones regulates functions throughout body
It is located at the centre of the base of the cranium in the middle fossa.
What does the sphenoid bone articulate with and name features?
Every other bone in the cranium and some facial bones - zygomata; ethmoid; vomer and palatines.
Lesser wing with frontal bone
Sphenoid body with ethmoid
Tips of greater wings with parietal bones
Edges of greater wings with temporal bones
Sphenoid body with occiput.
With occiput if forms the SBS.
MIDDLE CRANIAL FOSSA.
Location of sella turcica in sphenoid body.
Sella turcica houses pituitary gland and stalk which is washed by CSF and covered by diaphragma sellae which attaches to clinoid processes of sphenoid body. Tentorium attaches to anterior and posterior clinoid processes.
Optic chiasma is in front of pituitary gland.
Superior Orbital Notch - between sphenoid G and L wings - Nerves 3,4,5 (ophthalmic division), 6 and ophthalmic vein enter orbit here.
Inferior Orbital Notch - between sphenoid G wing and Maxilla = maxillary division Trigeminal nerve enters orbit here.
Optic canal - optic nerve and ophthalmic artery in sphenoid - between body and lesser wing).
The pterygoid process of the sphenoid - Each process divides into a medial pterygoid plate and a lateral pterygoid plate which terminate behind the nasal cavity and palate.
The lateral pterygoid plate is the origin of the medial and lateral pterygoid muscles and assists the jaw to move side to side whilst chewing.
The medial pterygoid plate (along with the masseter muscle) allows the jaw to move up and down during chewing.
What is the SBS and why is it so important?
SBS is PIVOTAL FULCRUM ROUND WHICH THE WHOLE BONY STRUCTURES OPERATE IN THE CS SYSTEM.
Cartilaginous joint between sphenoid body and basiocciput.
Because its mobile and central, SBS is affected in patterns in early life which will follow through to later life.
It is pivotal, meaning it reflects imbalances and tensions from all systems, therefore to restore balance and CS rhythm here means restoring at a deep level.
What is the sphenoid made up of?
2 greater wings - form part of the floor of middle cranial fossa.
2 lesser wings - emerge top of sphenoid body to run along back edge of front cranial fossa.
2 pterygoid processes - project down from sphenoid body and each dividing into a medial and lateral pterygoid plate which terminate behind the nasal cavity and palate.
Superior surface of sphenoid body is shaped to form SELLAE TURCICA - houses pituitary gland (ENDOCRINE).
Sellae Turcica -
2 anterior clinoid processes (project from front)
2 posterior clinoid processes (project from back)
What are membranous attachments to the sphenoid?
Lined with membrane
Tentorium cerebelli projects forward and attaches to anterior and posterior clinoid processes to form a double membranous sheet.
Sella Turcica of sphenoid is covered by a membrane which stretches across the 4 clinoid processes and down sides of sphenoid body. It covers pituitary glands and stalk to ensure it stays in subarachnoid space and washed by CSF. Blends into surrounding membranes.
What is the CS motion of the sphenoid?
Flexion - sphenoid arcs forward and down (with frontal bone) and occiput tucking in towards neck. Basilar portion moves anteriorly and superiorly.
Extension - sphenoid comes back and up hinging around SBS. Occiput draws back and up. Basilar portion of occiput moves posteriorly and inferiorly.
What is the SBS release?
Sphenoid may follow into flexion or extension - follow - notice build up of tension to release.
Sphenoid may draw into compression at SBS -
What does a compression at the SBS reflect?
Reflecting fall, birth trauma, trauma to head, compression to occiput or lumbosacral area, could reflect personality - depression, contracted, withdrawn.
Who devised the framework of 6 SBS patterns?
Sutherland
What is the purpose of the 6 SBS patterns?
To evaluate the CS system more fully BUT see what is reflected in the WHOLE system
What is perfect fluency of SBS Flexion and Extension?
Motion is fluent; fluidic; easeful and balanced.
What is a Torsion SBS pattern reflect?
A twist in the body - pelvis; vertebrae; knee; neck; membrane; birth pattern. Might be same side or other.
Describe the SBS Torsion pattern?
The sphenoid twists superiorly on one side in relation to the occiput, while the other side twists inferiorly in relation to the occiput.
Describe a Left Sided SBS Torsion?
The sphenoid greater wing twists superiorly on the left and inferiorly on the right, relative to the occiput.
What would the therapist feel in an SBS torsion?
1 thumb twists superiorly towards the top of the therapists head whilst the other thumb twists superiorly towards the patients feet.
What does a Side Bending SBS pattern mean?
There is a sidebend restriction somewhere in the body.
What happens at the SBS in a side bending pattern?
At the SBS, there is a gapping between the sphenoid body and basi-occiput on 1 side with a narrowing on the other side - therapist will experience this as a bulge on one side of the head, with the other side of the head seeming to cave in.
What are the causes of a side bend restriction at the SBS?
Scoliosis; pelvic imbalance; muscular tension on one side; contraction around pericardium; head injury.
What does a Lateral Shift mean at the SBS?
There is a lateral shift pattern held in the body.
Describe a lateral shift SBS pattern?
At the SBS, the sphenoid will shift directly to one side in relation to the occiput.
