9- Mixed Anatomy (2)MSQs Only Flashcards
100 of 610
A 38 year old lady is due to undergo a parathyroidectomy for hyperparathyroidism. At operation the inferior parathyroid gland is identified as being enlarged. A vessel is located adjacent to the gland laterally. This vessel is most likely to be the:
Common carotid artery
The common carotid artery is a lateral relation of the inferior parathyroid.
103 of 610
A 60 year old female attends the preoperative hernia clinic. She reports some visual difficulty. On examination she is noted to have a homonymous hemianopia. Where is the lesion most likely to be?
Optic tract
………………………………….
Lesions before optic chiasm:
Monocular vision loss = Optic nerve lesion
Bitemporal hemianopia = Optic chiasm lesion
Lesions after the optic chiasm:
Homonymous hemianopia = Optic tract lesion
Upper quadranopia = Temporal lobe lesion
Lower quadranopia = Parietal lobe lesion
Unfortunately we thought as surgeons we could forget about visual field defects!
However the college seem to like them. Remember a homonymous hemianopia is indicative of an optic tract lesion. Parietal lobe lesions tend to cause inferior quadranopias and there is a bitemporal hemianopia with optic chiasm lesion or pituitary tumours.
102 of 610
During an Ivor Lewis Oesophagectomy for carcinoma of the lower third of the oesophagus which structure is divided to allow mobilisation of the oesophagus?
Azygos vein
The azygos vein is routinely divided during an oesophagectomy to allow mobilisation. It arches anteriorly to insert into the SVC on the right hand side.
101 of 610
What is the largest branch of the brachial artery?
Profunda brachii artery
The profunda brachii artery is the largest branch and then continues in the radial groove of the humerus.
104 of 610
Which of the following structures separates the subclavian artery from the subclavian vein?
Scalenus anterior
The artery and vein are separated by scalenus anterior. This muscle runs from the transverse processes of C3,4,5 and 6 to insert onto the scalene tubercle of the first rib.
105 of 610
A 67 year old man is undergoing an angiogram for gastro intestinal bleeding. The radiologist advances the catheter into the coeliac axis. At what spinal level does this vessel typically arise from the aorta?
T12
The coeliac axis lies at T12, it takes an almost horizontal angle off the aorta. It has three major branches.
106 of 610
Which of the nerves below innervates the tensor tympani muscle?
Trigeminal
The tensor tympani muscle (in conjunction with stapedius) helps to mitigate the effects of loud sounds. The tensor tympani is innervated by the trigeminal nerve (the stapedius by the facial). In some people with hyperacousia, the tensor tympani muscle does not function normally.
107 of 610
A 34 year old male is being examined in the pre-operative assessment clinic. A murmur is identified in the 4th intercostal space just next to the left side of the sternum. From where is it most likely to have originated?
Tricuspid valve
The tricuspid valve is generally referred to being best auscultated adjacent to the sternum. The plane of projected sound from the mitral area is best heard in the region of the cadiac apex.
109 of 610
Which of the following structures lies posterior to the femoral nerve in the femoral triangle?
Iliacus
The iliacus lies posterior to the femoral nerve in the femoral triangle. The femoral sheath lies anterior to the iliacus and pectineus muscles.
108 of 610
The vertebral artery traverses all of the following except?
Transverse process of C6
Transverse process of the axis
Vertebral canal
Foramen magnum
Intervertebral foramen (Right)
………………………………………….
The vertebral artery passes through the foramina which are located in the transverse processes of the cervical vertebra, it does not traverse the intervertebral foramen.
110 of 610
A 24 year old lady is stabbed in the buttock. Following the injury the wound is sutured in the emergency department. Eight weeks later she attends the clinic, as she walks into the clinic room she has a waddling gait and difficulty with thigh abduction. On examination she has buttock muscle wasting. Which nerve has been injured?
Superior gluteal nerve
Damage to the superior gluteal nerve will result in a Trendelenburg gait.
111 of 610
A 44 year old man is undergoing a parotidectomy and the surgeon is carefully preserving the facial nerve. Unfortunately his trainee then proceeds to divide it. Which of the following will not be affected as a result?
Taste sensation from anterior two thirds of the tongue
The chorda tympani branches inside the facial canal and will therefore be unaffected by this most unfortunate event! The corneal reflex is mediated by the opthalmic branch of the trigeminal nerve sensing the stimulus on the cornea, lid or conjunctiva; the facial nerve initiates the motor response of the reflex.
113 of 610
A 32 year old rugby player is hit hard on the shoulder during a rough tackle. Clinically, his arm is hanging loose on the side. It is pronated and medially rotated. What structure is most likely to have been compromised?
Brachial trunks C5-6
The patient has an Erb’s palsy involving brachial trunks C5-6.
INJURY OF THE BRACHIAL PLEXUS
(t) Complete avulsion of all roots of the plexus :leads to :
paralysis of all muscles of upper limb except trapezius
Supplied by supraclavicular and intercostobrachial respectively
(b) anaesthesia of all skin of u-L except skin of tip of shoulder &floor of axilla.
(2) Injury of the upper trunk (C5,6) :Erb’s paralysis : leads ta:
(a) paralysis of abductors &lat-rotators of arm+Flexors &supinators of forearm
(b) anaesthesia of skin of lat-aspect of forearm & lower/2 of arm.
(c) Deformity: porter’s or policeman tip position-
(3) Injury of the lower trunk (C8,TI) : Klumpke’s paralysis : leads to:
(a) paralysis of flexors of wrist & fingers +all intrinsic muscles of the hand.
b andesthesia of the skin along the ulnar border of forearm &hand.
(e) Deformity : claw hand deformity
112 of 610
A 73 year old man undergoes an excision biopsy of a lymph node that is closely applied to sternocleidomastoid. This muscle is mobilized and a nerve that is present is damaged. Which muscle below is most likely to be affected?
Trapezius
The accessory nerve has a number of lymph nodes applied to it near the sternocleidomastoid muscle. It is particularly at risk if SCM is mobilized. If injured, the trapezius muscle and SCM will be paralysed.
114 of 610
You are assisting in an open right adrenalectomy for a large adrenal adenoma. The consultant is distracted and you helpfully pull the adrenal into the wound to improve the view. Unfortunately this is followed by brisk bleeding. The vessel responsible for this is most likely to be:
Inferior vena cava
It drains directly via a very short vessel. If the sutures are not carefully tied then it may be avulsed off the IVC. An injury best managed using a Satinsky clamp and a 6/0 prolene suture.
117 of 610
Which of the following does not pass through the superior orbital fissure?
Opthalmic artery
…………………………
Mnemonic for the nerves passing through the supraorbital fissure:
Live Frankly To See Absolutely No Insult
Lacrimal
Frontal
Trochlear
Superior Division of Oculomotor
Abducens
Nasociliary
Inferior Division of Oculomotor nerve
The opthalmic artery arises from the internal carotid immediately after it has pierced the dura and arachnoid. It runs through the optic canal below the optic nerve and within its dural and arachnoid sheaths. It terminates as the supratrochlear and dorsal nasal arteries.
115 of 610
A 72 year old man has a fall. He is found to have a fractured neck of femur and goes on to have a left hip hemiarthroplasty. Two months post operatively he is found to have an odd gait. When standing on his left leg his pelvis dips on the right side. There is no foot drop. What is the cause?
Superior gluteal nerve damage
This patient has a trendelenburg gait caused by damage to the superior gluteal nerve causing weakness of the abductor muscles. Classically a patient is asked to stand on one leg and the pelvis dips on the opposite side. The absence of a foot drop excludes the possibility of polio or L5 radiculopathy.
116 of 610
At which level is the hilum of the left kidney located?
L1
Remember L1 (‘left one’) is the level of the hilum of the left kidney
118 of 610
Which of the muscles listed below is attached to the anterior aspect of the fibrous capsule that encases the elbow joint?
Brachialis
The brachialis inserts some of its fibres into the fibrous joint of the elbow capsule and when it contracts, it helps to flex the joint.
119 of 610
Parasympathetic fibres innervating the parotid gland originate from which of the following?
Otic ganglion
Secretion of saliva by the parotid gland is controlled by nerve fibres originating in the inferior salivatory nucleus; these leave the brain via the tympanic nerve (branch of glossopharyngeal nerve (CN IX), travel through the tympanic plexus (located in the middle ear), and then form the lesser petrosal nerve until reaching the otic ganglion. After synapsing in the Otic ganglion, the postganglionic (postsynaptic) fibres travel as part of the auriculotemporal nerve (a branch of the mandibular nerve (V3) to reach the parotid gland.
Inferior salivary nucleus - tympanic n of IX - tympanic
plexus in middle ear - lesser petrosal n ->- otic
ganglion ->- auriculotemporal ot V - parotid gland
121 of 610
At which of the following levels does the inferior thyroid artery enter the thyroid gland?
C6
It enters the gland at C6.
120 of 610
An occlusion of the anterior cerebral artery may compromise the blood supply to the following structures except:
Medial inferior surface of the frontal lobe
Corpus callosum
Medial surface of the frontal lobe
Olfactory bulb
Brocas area ( Right)
…………………………………
Brocas area is usually supplied by branches from the middle cerebral artery.
122 of 610
Which of the cranial nerves listed below is least likely to carry parasympathetic fibres?
II
Cranial nerves carrying parasympathetic fibres
X IX VII III (1973)
The optic nerve carries no parasympathetic fibres.
The cranial preganglionic parasympathetic nerves arise from specific nuclei in the CNS. These synapse at one of four parasympathetic ganglia; otic, pterygopalatine, ciliary and submandibular. From these ganglia the parasympathetic nerves complete their journey to their target tissues via CN V (trigeminal) branches (ophthalmic nerve CNV branch 1, Maxillary nerve CN V branch2, mandibular nerve CN V branch 3)
123 of 610
An elderly man develops a squamous cell carcinoma affecting the lobule of his ear. To which lymph node is the lesion most likely to metastasize?
Superficial cervical nodes
The lobule drains to the superficial cervical nodes.