Head, neck and trunk Flashcards
How many bones are in the skull?
22
How many cranium bone are there?
8
How many facial bones are there?
14
What are the functions of the skull?
Protects the brain.
A site of muscle attachment.
Provides facial expressions.
Provide some key functions in relation to the entry of the respiratory and digestive systems.
What is the function of the cranium bones?
Form the vault that encloses and protect the brain.
Name the cranium bones
Parietal (x2)
Temporal (x2)
Frontal
Occipital
Ethmoid
Sphenoid
What is the function of the facial bones?
Form sinuses
Offer sound chambers
Offer unique inner surfaces which attach membranes, blood vessels and nerves.
Name the facial bones
Inferior nasal concha (x2)
Lacrimal (x2)
Mandible
Maxilla (x2)
Nasal bones (x2)
Palatine bones (x2)
Vomer
Zygomatic bones (x2)
What are sutures?
Where bones of the skull ossify and become united over time.
Name three sutures
Sagittal suture
Lambdoid suture
Coronal suture
What bones are united at the sagittal suture?
The two parietal bones.
What bones are united at the lambdoid suture?
The parietal bones and the sutural bone.
Name three muscles
Orbicularis oris
Orbicularis oculi
Masseter
Describe the orbicularis oris
Circular muscles that surround the mouth.
It functions to close the mouth.
It also functions by supporting swallowing, whistling, chewing and pronunciation of works.
Origin = maxilla and mandible
Insertion = skin around the lips
Describe the orbicularis occuli
Circular muscle
It is key in closing the eye and depressing the forehead.
Origin = zygomatic process
Insertion = around the eye socket
Describe the masseter
Jaw muscle
Elevates the mandible (jawbone)
If it gets smaller it will elevate the jaw.
Based on its size and weight it is the strongest muscle in the body.
Origin = zygomatic process
Insertion = mandible
Describe the atlanto-occipital joint
The joint between the atlas and occiput.
It is an oval shape process which fits into an elongated cavity.
It allows flexion, extension and lateral flexion.
It is an ellipsoid joint.
It allows the movement of shaking the head up and down.
Describe the atlanto-axial joint
Joint between atlas and axis.
They are bilateral which allow a gliding motion and allow some pivoting motion around the dens.
The dens provide the pivot for rotation.
It allows the movement of shaking the head from left to right.
What does the atlas do?
Supports the head
Name 5 muscles of the neck
Platysma
Sternocleidomastoid
Scalene
Trapezius
Levator scapulae
Describe the platysma
Origin = skin/fascia of the infra and supra clavicular regions.
Insertion = lower border of the mandible, skin of the buccal/check region, lower lip, modiolus, orbicularis oris muscle.
Action = depresses mandible. Tenses skin of the neck.
Describe the sternocleidomastoid
Runs lateral to the neck.
Origin = sternum, medial clavicle
Insertion = mastoid process and the temporal and occipital bones
Action: lateral flexion of the head and rotation of the neck
Describe the scalene
Anterior, posterior, and middle.
Located in the lateral aspect of the neck and collectively form part of the posterior triangle of the neck.
Origin = transverse process of the cervical vertebrae.
Insertion = 1st and 2nd rib.
Action: accessory muscles in respiration. Involves elevation of the ribs during inspiration which help increase the size of the lungs.
Describe the trapezius
Origin = deep within suborbital area and spinal processes of the cervical and thoracic vertebrae.
Insertion = spine, clavicle and scapula
Action = elevation and depression of the scapula.
It is a large muscle that crosses several areas, and its different portions allow different movements.
Describe the levator scapulae
Origin = posterior tubercle of the transverse processes
Insertion = superior-medial scapula
Lies deeper to the sternocleidomastoid and deeper to the trapezius.
Action: elevates the scapulae and tilts the glenoid cavity. When it is activity, we see some downward rotation of the scapula.
Name the primary muscles during inspiration
External intercostals: elevate the ribs upwards
Diaphragm: flattens and descends
Name the accessory muscles during inspiration
Sternocleidomastoid: elevates the sternum
Scalene: elevates the upper ribs
Pectoralis minor: help to increase thoracic cavity
What happens during quiet breathing (Expiration)?
Passive elastic recoil of the lungs, rub cage and diaphragm.
What muscles are involved in active breathing (expiration)?
Internal intercostals: pull the ribs downwards.
Abdominals: helps pull the ribs downwards and compress the thoracic cavity.
Quadratus lumborum
Describe the diaphragm
Origin: lower 6 costal cartilage, xiphoid processes, L1-L5 vertebrae
Insertion: central tendon of the diaphragm
Describe the external intercostals
Inspiration
Origin: inferior rib
Insertion: superior rib
Action: expansion of the chest
Describe the internal intercostals
Expiration
Origin: superior rib
Insertion: inferior rib
Action: draw the chest inwards
What sports are more prone to neck injuries?
Wrestling
Judo
Ice hockey
Rugby
Football
How can neck injuries be sustained?
Repetitive contact
High forces
Hyperextension/hyperflexion of the cervical spine during collisions/impacts can lead to injury.
What are the muscles in the neck important for?
Providing stability
Ensure safe position of the head
Control head and neck (limit end range of motion)
Stabilise the head and reduce the risk of sport related concussions.
Name neck injuries
Joint facet
Muscle strains
Nerve root neuropathy
Paralysis
