anatomy 20.04 Flashcards
An 18 year old lady with troublesome hyperhidrosis of the hands and arms is due to undergo a sympathectomy to treat the condition. Which of the following should the surgeons divide to most effectively treat her condition?
Sympathetic ganglia at T1, T2 and T3
Sympathetic ganglia at T2 and T3
Sympathetic ganglia at T1 and T2
Stellate ganglion
Superior cervical ganglion
Useful mnemonic: T2 & T3 Make the hands sweat-free
To treat hyperhidrosis the sympathetic ganglia at T2 and T3 should be divided. Dividing the other structures listed would either carry a risk of Horners syndrome or be ineffective.
Into which of these veins does the middle thyroid vein drain?
Vertebral
External jugular
Internal jugular
Subclavian
Anterior jugular
It drains to the internal jugular vein. Which is one of the reasons why it bleeds so copiously if a ligature slips.
Superior and middle thyroid veins - into the IJV
Inferior thyroid vein - into the brachiocephalic veins
Which of the following is a recognised tributary of the retromandibular vein?
Internal jugular vein
External jugular vein
Anterior temporal diploic vein
Maxillary vein
Inferior opthalmic vein
The retromandibular vein is formed from the union of the maxillary and superficial temporal veins.
Formed by a union of the maxillary vein and superficial temporal vein
It descends through the parotid gland and bifurcates within it
The anterior division passes forwards to join the facial vein, the posterior division is one of the tributaries of the external jugular vein
A builder falls off a ladder whilst laying roof tiles. He sustains a burst fracture of L2. The MRI scan shows complete nerve transection at this level, as a result of the injury. Which clinical sign will not be present initially?
Flaccid paralysis of the legs
Extensor plantar response
Sensory loss in the legs
Incontinence
Areflexia
In lower motor neuron lesions everything is reduced
The main purpose of this question is to differentiate the features of an UMN lesion and a LMN lesion. The features of a LMN lesion include:
Flaccid paralysis of muscles supplied
Atrophy of muscles supplied.
Loss of reflexes of muscles supplied.
Muscles fasciculation
For lesions below L1 LMN signs will occur. Hence in an L3 lesion, there will be loss of the patella reflex but there will be no extensor plantar reflex.
Structures posterior to medial malleolus?
Tom, Dick And Nervous Harry Tibialis posterior flexord Digitorum longus tibial Artery tibial Nerve flexor Hallucis longus
Which muscle is not innervated by the trigeminal nerve?
Medial pterygoid
Mylohyoid
Stylohyoid
Masseter
Temporalis
Stylohyoid is innervated by the facial nerve.
Motor - mastication, MYLOHOID, anterior belly of digastric, tensor tympani, tensor palati
Which of the following nerves is the primary source of innervation to the anterior scrotal skin?
Iliohypogastric nerve
Pudendal nerve
Ilioinguinal nerve
Femoral branch of the genitofemoral nerve
Obturator nerve
The pudendal nerve may innervate the posterior skin of the scrotum. The anterior innervation of the scrotum is primarily provided by the ilioinguinal nerve. The genital branch of the genitofemoral nerve provides a smaller contribution.
A 70 year old man is due to undergo an arterial bypass procedure for claudication and foot ulceration. The anterior tibial artery will form the site of the distal arterial anastomosis. Which of the following structures is not closely related to it distally?
Interosseous membrane
Deep peroneal nerve
Tibialis posterior
Extensor hallucis longus
Dorsalis pedis artery
As an artery of the anterior compartment, the anterior tibial artery is closely related to tibialis anterior. The tibialis posterior is related to it at its origin.
Which of the following pairings are incorrect?
Aortic bifurcation and L4
Transpyloric plane and L1
Termination of dural sac and L4
Oesophageal passage through diaphragm and T10
Transition between pharynx and oesophagus at C6
Vena cava T8 (eight letters)
Oesophagus T10 (ten letters)
Aortic hiatus T12 (twelve letters)
It terminates at S2, which is why it is safe to undertake an LP at L4/5 levels. The spinal cord itself terminates at L1.
A 28 year old man requires a urethral catheter to be inserted prior to undergoing a splenectomy. Where is the first site of resistance to be encountered on inserting the catheter?
Bulbar urethra
Membranous urethra
Internal sphincter
Prostatic urethra
Bladder neck
The membranous urethra is the least distensible portion of the urethra. This is due to the fact that it is surrounded by the external sphincter.
Which of the following statements relating to the Cavernous Sinus is false?
The pituitary gland lies medially
The internal carotid artery passes through it
The temporal lobe of the brain is a lateral relation
The mandibular branch of the trigeminal and optic nerve lie on the lateral wall
The ophthalmic veins drain into the anterior aspect of the sinus
The veins that drain into the sinus are important as sepsis can cause cavernous sinus thrombosis. The maxillary branch of the trigeminal and not the mandibular branches pass through the sinus
OTOM CAT Lateral wall: (from top to bottom:) Oculomotor nerve Trochlear nerve Ophthalmic nerve Maxillary nerve
Contents:
(from medial to lateral:)
Internal carotid artery (and sympathetic plexus)
Abducens nerve
The thebesian veins contribute to the venous drainage of the heart. Into which of the following structures do they primarily drain?
Great cardiac vein
Atrium
Superior vena cava
Oblique vein
Small cardiac vein
The thebesian veins are numerous small veins running over the surface of the heart they drain into the heart itself. Usually this is to the atrium directly.
A 73 year old man presents with a tumour at the tip of his tongue. To which of the following regions will the tumour initially metastasise?
Sub mental nodes
Ipsilateral deep cervical nodes
Tonsil
Ipsilateral superficial cervical nodes
Contralateral deep cervical nodes
At which of the following vertebral body levels does the common carotid artery typically bifurcate into the external and internal carotid arteries?
C4
C2
C1
C6
C7
It terminates at the upper border of the thyroid cartilage, Which is usually located at C4.
Through which of the following foramina does the genital branch of the genitofemoral nerve exit the abdominal cavity?
Superficial inguinal ring
Sciatic notch
Obturator foramen
Femoral canal
Deep inguinal ring
The genitofemoral nerve divides into two branches as it approaches the inguinal ligament. The genital branch passes anterior to the external iliac artery through the deep inguinal ring into the inguinal canal. It communicates with the ilioinguinal nerve in the inguinal canal (though this is seldom of clinical significance).
Leg dermatomes (prolapsed disc)?
L3 - knee
L3 - sensory loss over anterior knee (knee joint) Weak quadriceps Reduced knee reflex Positive femoral stretch test
L5 - sensory loss dorsum of foot
Weakness in foot and big toe dorsiflexion
Reflexes intact
Positive sciatic nerve stretch test
S1 - sensory loss posterolateral aspect of leg and lateral aspect of foot
Weakness in plantar flexion of foot
Reduced ankle reflex
Positive sciatic nerve stretch test
Leg dermatomes (prolapsed disc)?
L3 - knee
L3 - sensory loss over anterior knee (knee joint) Weak quadriceps Reduced knee reflex Positive femoral stretch test
L5 - sensory loss dorsum of foot
Weakness in foot and big toe dorsiflexion
Reflexes intact
Positive sciatic nerve stretch test
S1 - sensory loss posterolateral aspect of leg and lateral aspect of foot
Weakness in plantar flexion of foot
Reduced ankle reflex
Positive sciatic nerve stretch test
Leg dermatomes (prolapsed disc)?
L3 - knee
L3 - sensory loss over anterior knee (knee joint) Weak quadriceps Reduced knee reflex Positive femoral stretch test
L5 - sensory loss dorsum of foot
Weakness in foot and big toe dorsiflexion
Reflexes intact
Positive sciatic nerve stretch test
S1 - sensory loss posterolateral aspect of leg and lateral aspect of foot
Weakness in plantar flexion of foot
Reduced ankle reflex
Positive sciatic nerve stretch test
A 45 year old lady develops severe back pain and on examination is found to have clinical evidence of an L5/ S1 radiculopathy. Her symptoms deteriorate and eventually a laminectomy is performed. During a posterior surgical approach the surgeons encounter a tough ligamentous structure lying anterior to the spinous processes. This structure is most likely to be the
Transverse spinal ligament
Supraspinal ligament
Anterior longitudinal ligament
Ligamentum flavum
Posterior longitudinal ligament
The ligamentum lies in this position, as illustrated below:
A 35 year old man is admitted to hospital with vomiting, nausea and severe headaches. An MRI scan reveals a tumour of the cerebellopontine angle. Which one of the following pairs of cranial nerves is most likely to be compressed by this tumour?
Accessory and vagus
Facial and vagus
Facial and vestibulocochlear
Glossopharyngeal and vestibulocochlear
Vagus and vestibulocochlear
The cerebellopontine angle is located between the superior and inferior limbs of the angular cerebellopontine fissure formed by the petrosal cerebellar surface folding around the pons and middle cerebellar peduncle. The cerebellopontine fissure opens medially and has superior and inferior limbs that meet at a lateral apex. The fourth through the eleventh cranial nerves are located near or within the angular space between the two limbs commonly referred to as the cerebellopontine angle. The commonest lesion to affect this site is an acoustic neuroma. Therefore the vestibulocochlear nerve is commonly compromised. Larger lesions may also affect the facial nerve which lies closest to this site.
A 56 year old machinist has his arm entrapped in a steel grinder and is brought to the emergency department. On examination, he is unable to extend his metacarpophalangeal joints and abduct his shoulder. He has weakness of his elbow and wrist. What has been injured?
Ulnar nerve
Axillary nerve
Medial cord of brachial plexus
Lateral cord of brachial plexus
Posterior cord of brachial plexus
The posterior cord gives rise to:
Radial nerve ((innervates the triceps, brachioradialis, wrist extensors, and finger extensors)
Axillary nerve (innervates deltoid and teres minor)
Upper subscapular nerve (innervates subscapularis)
Lower subscapular nerve (innervates teres major and subscapularis)
Thoracodorsal nerve (innervates latissimus dorsi)
This is a description of a posterior cord lesion. Remember that the posterior cord gives rise to the axillary and radial nerve.
