Anatomy Pratical 1 Flashcards
what are the 3 main salivary glands
parotid
submandibular
sublingual
what is the largest salivary gland
parotid
where does the parotid gland enter the mouth
2nd molar
where does submandibular enter the mouth
small prominences on either side of the lingual frenulum
where does sublingual enter the mouth
they have minor sublingual ducts and major sublingual ducts
a major sublingual duct (of Bartholin) can be present in some people.
what is the nerve supply of the parotid duct
glossopharyngeal nerve (cranial nerve IX).
- Sensory innervation is supplied by the auriculotemporal nerve (gland) and the great auricular nerve (fascia).
- Sympathetic innervation originates from the superior cervical ganglion, part of the paravertebral chain.
what nerve passes through he parotid gland
facial nerve
which foramen does the facial nerve exit the cranium form
stylomastoid foramen.
o Which muscle(s) innervated by the facial nerve is involved during chewing (but is not a muscle of mastication)?
buccinator
what is the nerve supple to the submandibular and sublingual glands
facial nerve
name the 4 main muscles involved with mastication and what is there nerve supply
Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
- innervated by a branch of the trigeminal nerve (CN V), the mandibular nerve.
which nerve is the motor supply to the tongue
hypoglossal
what are the phases of swallowing
pharyngeal phase
oesophageal phase
what causes the pharyngeal phase
Stimuli in the oropharynx (and laryngopharynx) provoke the pharyngeal phase.
which nerve is sensory in the oropharynx and forms the afferent limb of the pharyngeal phase
glossopharyngeal
- afferent limb is glossopharyngeal phase
which nerve forms the efferent limb of the pharyngeal phase
vagus nerve
what are inhibited in the pharyngeal phases
chewing, breathing, coughing and vomiting are inhibited.
what contracts when you swallow food
- The pharynx widens and shortens to receive the bolus of food as the suprahyoid and longitudinal pharyngeal muscles contract elevating the larynx.
- There is then an INVOLUNTARY sequential contraction of the pharyngeal constrictor muscles creating a peristaltic ridge (involuntary because it is part of a reflex action
what type of muscle is pharyngeal muscle
skeletal
- therefore it has a somatic supply
what prevents aspiration during swallowing
It is true vocal fold closure that is the primary laryngopharyngeal protective mechanism to prevent aspiration during swallowing.
- False vocal fold adduction and retroversion of the epiglottis also take place.
describe the oesophageal phase of swallowing
- involuntary neuromuscular control
- slower than the pharyngeal phase
- bolus enters the oesophagus and is propelled downwards by striated muscle and then by smooth muscle
- The upper oesophageal sphincter relaxes to let food pass, after which various striated constrictor muscles of the pharynx as well as peristalsis and relaxation of the lower oesophageal sphincter sequentially push the bolus of food through the oesophagus into the stomach.
what is the somatic nerve supply to the upper oesophagus
sympathetic and parasympathetic from the nucleus ambiguus
what is the autonomic supply to smooth muscle in the lower oesophagus
sympathetic and parasympathetic from the dorsal motor nucleus
what is dysphagia
difficulty swallowing
what are the risk factors of aspirating foreign materials into the lung
- Poor gag reflex in people who are not alert (unconscious or semi-conscious) after a stroke or brain injury
- Drinking large amounts of alcohol
- General anaesthesia
- Old age
- Problems with swallowing
- Coma
- Being less alert due to medicines, illness, or other reasons
where does the oesophagus exited from
C6-T1
- cricoid to the stomach
what is the diameter of oesophagus
approximately 2cm in diameter
what are the upper half and lower half relations of the oesophagus
The relations of the upper half of the Oesophagus (C6 – T4):
- Posteriorly: the vertebral column.
- Anteriorly: the Trachea
- On both sides: the dome of the Pleura and superior lobe of each lung. In the groove made by the trachea and Oesophagus you will find the Recurrent Laryngeal Nerve.
The relations to the lower half of the Oesophagus (T4 – T10):
- Posteriorly: the vertebral column.
- Anteriorly: the heart (left Atrium) (transoesophageal echocardiograms produce some of the most detailed images of the heart, especially those structures difficult to see using transthoracic echocardiography)
- On the left: descending thoracic aorta.
- On the right: the azygos vein and inferior lobe of right lung.
what are the two sphincters in the oesophagus
upper oesophageal sphincter
lower oesophageal sphincter
describe the two sphincters in the oesophagus
upper oesophageal sphincter
- voluntary
- skeletal muscle mainly comprised of the inferior pharyngeal constrictor/cricopharyngeus
Lower Oesophageal Sphincter (LOS)
- specialized segment of the circular muscle layer of the distal oesophagus.
- It functions as the first antireflux barrier protecting the oesophagus from the acidic gastric content.
o Where are foreign objects most likely to lodge in the pharynx and oesophagus? Why?
upper oesophageal spincther - voluntary and anatomical sphincter - first one it comes into contact with
what are the three constrictions of the oesopgahus
- upper oesophageal sphincter
- abdominal aorta causes it to pinch
- lower oesophageal sphincter
what is a hiatus hernia
A hiatus hernia or hiatal hernia is the protrusion (or herniation) of the upper part of the stomach into the thorax through a tear or weakness in the diaphragm.
what can a hiatus hernia result in
Hiatus hernias often result in heartburn but may also cause chest pain or pain with eating.
what is the most common cause of a hiatus hernia
obesity
what is the most common form of a hiatus hernia
. Sliding hiatal hernias are the most common form.
what is the inguinal ligament
• The inguinal ligament is a thickening of the external oblique aponeurosis and spans from the anterior superior ileac spine (ASIS) to the pubic tubercle (PT) of the pelvis.
what is the inguinal canal
• The inguinal canal is a space that passes obliquely through abdominal wall in the inguinal region. The inguinal canal is found over the medial half of the inguinal ligament (i.e. the inguinal ligament forms the floor of the canal).
what forms the wall of the inguinal canal
• The anterolateral muscles of the abdominal wall (external oblique, internal oblique and transversus abdominis) and their aponeuroses form the walls of the inguinal canal
what is the deep ring and where does it open
o Deep (Internal) Ring: is an opening in the transveralis fascia and is located at the midpoint of the inguinal ligament. This is the point halfway between the ASIS and the PT.
what is the superficial ring and where does it open
o Superficial (External) ring: is an opening in external oblique aponeurosis. It is located above the PT.
what does the inguinal canal contain
o spermatic cord and ilioinguinal nerve in the MALE
o round ligament of the uterus and ilioinguinal nerve in the FEMALE