Head and Neck Anatomy (1-3) Flashcards
State the superior and inferior border of the neck
SUPERIOR
Inferior border of mandible
Angle of mandible
Mastoid process
Superior nuchal line (for attachment of muscles at back of neck)
External occipital protuberance (EOP)
INFERIOR
Thoracic inlet / Superior thoracic aperture (STA)
Anterior: Manubrium + 1st costal cartilage
Posterior: T1 vertebra
Lateal: 1st rib
State the 3 cartilages located in neck from superior to inferior.
State any boney landmarks.
- HYOID BONE
- THYROID CARTILAGE - upper border is C3/4 (bifurcation of common carotid A into ICA and ECA)
- CRICOID CARTILAGE - lower border is C6 (superior end of oesophagus and trachea)
State the function of cricothyroid ligament and cricothyroid muscle
CRICOTHYROID LIGAMENT - helps to stabilise and anchor thyroid cartilage to cricoid cartilage
CRICOTHYROID MUSCLE - pulls thyroid cartilage downwards to tense vocal folds and form higher pitch sounds
Name the nerve suppllying cricothyroid. Name the nerve supplying all other structures of larynx
cricothyroid - external laryngeal n
all others - recurrent laryngeal n
both nerves are branches of vagus n (CN X)
State the borders of the anterior triangle of neck
Superior: Inferior margin of mandible
Medial: Midline of neck
Lateral: Anterior margin of SCM
State the borders of the posterior triangle of neck
Inferior: Clavicle
Medial: Posterior margin of SCM
Lateral: Anterior margin of trapezius
Label the structures in the neck
Name the 3 layers involved in the deep fascia of the neck.
State the clinial significance of each layer.
(1) INVESTING LAYER
- Provides protection to structures in neck
- Prevents spread of infection
- Lubrication → enables structures in the neck to move and pass over one another during swallowing
(2) PRETRACHEAL LAYER
- Encloses thyroid gland and laterally fuses with carotid sheath
(3) PREVERTEBRAL LAYER
- Encloses the prevertebral muscles and vertebra
State the 3 structures enclosed by the carotid sheath
- internal jugular V
- common carotid A
- CN X (vagus N)
State the contents of the prevertebral layer
- sympathetic trunk - superior, middle and inferiro cervical ganglion (SCG commonly used for sympathetic innervation of stuctures in head)
- phrenic nerve
- brachial plexus (brachial plexus block done above clavicle behind SCM)
Name and label the muscles in this diagram
State the 4 branches of the cervical plexus (C1-C4)
- lesser occipital
- great auricular
- transverse cervical
- supraclavicular
Name the 4 infrahyoid (strap) muscles
State the motor innervation of these muscles
- omohyoid
- sternohyoid
- sternothyroid
- thyrohyoid
Innervtion = ansa cervicalis (C1-C4) + sympathetic trunk (mainly superior cervical ganglion)
State the actions of platysma
- Pulls down the mandible → opens mouth
- Pulls corners of lips out to the side and down → frown
State the vessels located anterior and posterior and BETWEEN the scalenius anterior and medius.
anterior to SA/SM = subclavian V
posterior to SA = subclavian A
between SA and SM = brachial plexus + subclavian A