anatomy 21.04 Flashcards
The common peroneal nerve, or its branches, supply the following muscles except:
Peroneus longus
Tibialis anterior
Extensor hallucis longus
Flexor digitorum brevis
Extensor digitorum longus
Flexor digitorum is supplied by the tibial nerve.
Flexors are deep posterior!
A 34 year old lady suffers from hyperparathyroidism. The right inferior parathyroid is identified as having an adenoma and is scheduled for resection. From which of the following embryological structures is it derived?
Second pharyngeal pouch
Third pharyngeal pouch
Fourth pharyngeal pouch
First pharyngeal pouch
None of the above
The inferior parathyroid is a derivative of the third pharyngeal pouch. The superior parathyroid originates from the fourth pharyngeal pouch.
A 44 year old lady who works as an interior decorator has undergone a mastectomy and axillary node clearance to treat breast cancer. Post operatively, she comments that her arm easily becomes fatigued when she is painting walls. What is the most likely explanation?
Injury to the axillary nerve
Injury to the long thoracic nerve
Injury to the intercostobrachial nerve
Injury to the thoracodorsal nerve
Injury to the median pectoral nerve
The most likely explanation for this is that the thoracodorsal nerve has been injured. This will result in atrophy of latissimus dorsi and this will become evident with repetitive arm movements where the arm is elevated and moving up and down (such as in painting). Injury to the pectoral nerves may produce a similar picture but this pattern of injury is very rare and the pectoral nerves are seldom injured in breast surgery.
What is the function of intercostobrachial nerve?
It is the lateral branch of 2nd intercostal nerve. It is not divided into an anterior and a posterior branch, but is named as intercostobrachial nerve. It innervates the skin of the medial aspect of the arm
What does thoracodorsal nerve?
It is derived from posterior cord and innervates latissimus dorsi.
In which of the following cranial bones does the foramen spinosum lie?
Sphenoid bone
Frontal bone
Temporal bone
Occipital bone
Parietal bone
The foramen spinosum (which transmits the middle meningeal artery and vein) lies in the sphenoid bone.
A 42 year old lady is reviewed in the outpatient clinic following a routine surgical procedure. She complains of diminished sensation at the lateral aspect of her foot. Which of the following nerves is most likely to be affected?
Sural
Superficial peroneal
Deep peroneal
Medial plantar
Lateral plantar
The sural nerve supplies the lateral aspect of the foot. It runs alongside the short saphenous vein and may be injured in short saphenous vein surgery.
Which of the nerves below innervates the tensor tympani muscle?
Vestibulocochlear
Facial
Vagus
Trigeminal
Hypoglossal
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.
Which structure is least likely to be found at the level of the sternal angle?
Left brachiocephalic vein
Intervertebral discs T4-T5
Start of aortic arch
2nd pair of costal cartilages
Bifurcation of the trachea into left and right bronchi
The left brachiocephalic vein lies posterior to the manubrium, at the level of its upper border. The sternal angle refers to the transition between manubrium and sternum and therefore will not include the left brachiocephalic vein.
