FMGE 2018 - Anatomy Practice Questions

Q: Which branch of facial nerve supplies muscles of lower lip

Marginal mandibular. ***Marginal mandibular*** - The **marginal mandibular branch** of the facial nerve innervates muscles of the lower lip and chin, including the **depressor labii inferioris**, **depressor anguli oris**, and **mentalis**. - Damage to this nerve causes an inability to depress the lower lip, leading to an **asymmetric smile**. *Buccal* - The **buccal branch** primarily innervates the **buccinator muscle** and the muscles of the upper lip. - It is crucial for **cheek compression** (e.g., blowing or sucking) and expression around the mouth. *Cervical* - The **cervical branch** supplies the **platysma muscle**, a broad sheet of muscle in the neck that helps depress the mandible and draw down the corners of the mouth. - It does not directly innervate the muscles of the lower lip. *Temporal* - The **temporal branch** provides motor innervation to the muscles of the forehead and around the eye, including the **frontalis** and **orbicularis oculi**. - It is responsible for actions like raising the eyebrows and closing the eyelids.

Q: Pointing index finger is seen in which nerve injury

Median. ***Median*** - The **pointing index finger** sign occurs in **proximal median nerve injury** when attempting to make a fist, as the median nerve supplies **flexor digitorum superficialis (FDS)** and lateral half of **flexor digitorum profundus (FDP)**. - This creates the classic **"hand of benediction"** or **"pope's blessing"** sign where index and middle fingers remain extended due to loss of flexion capability. *Axillary* - Primarily innervates the **deltoid** and **teres minor muscles**, affecting **shoulder abduction** and external rotation. - Injury does not cause any **finger positioning abnormalities** or hand deformities. *Radial* - Injury causes **"wrist drop"** with inability to extend the wrist, thumb, and fingers at **MCP joints**. - Results in all fingers remaining **flexed due to unopposed flexor action**, not a pointing finger deformity. *Ulnar* - Injury causes **"claw hand"** deformity primarily affecting the **ring and little fingers** (4th and 5th digits). - Creates **hyperextension at MCP joints** and **flexion at PIP/DIP joints**, with the index finger typically less affected.

Q: Hypoglossal nerve supplies all of these muscles except:-

Palatoglossus. ***Palatoglossus*** - The **palatoglossus** muscle is innervated by the **pharyngeal plexus** (composed of contributions from the vagus and glossopharyngeal nerves), not the hypoglossal nerve. - It is the only extrinsic muscle of the tongue not supplied by the hypoglossal nerve, and its primary function is to elevate the posterior part of the tongue and narrow the oropharyngeal isthmus. *Styloglossus* - The **styloglossus** muscle is an **extrinsic tongue muscle** that originates from the styloid process and inserts into the side and undersurface of the tongue. - It is supplied by the **hypoglossal nerve** and acts to retract and elevate the tongue. *Genioglossus* - The **genioglossus** muscle is an **extrinsic tongue muscle** that originates from the mental spine of the mandible. - It is innervated by the **hypoglossal nerve** and is responsible for protruding and depressing the tongue, and its bilateral contraction is crucial in preventing airway obstruction during sleep (tongue falling back). *Hyoglossus* - The **hyoglossus** muscle is an **extrinsic tongue muscle** that originates from the hyoid bone and inserts into the side of the tongue. - It is supplied by the **hypoglossal nerve** and acts to depress and retract the tongue.

Q: Secondary ossification centre appears before birth at

Lower end of femur. Lower end of femur - The distal femur is one of the very few secondary ossification centers that appears before birth, specifically during the 9th month of gestation. - Its presence is an important indicator of fetal maturity and can be seen on prenatal imaging. Upper end of femur - The proximal femoral epiphysis typically develops its secondary ossification center after birth, usually between 3-6 months of age. - This timing is considerably later than the distal femur. Lower end of tibia - The secondary ossification center for the distal tibia appears after birth, generally around 1-2 years of age. - This is a common timeline for many secondary ossification centers. Lower end of fibula - The secondary ossification center for the distal fibula also appears after birth, typically between 6 months and 1 year of age. - This timing is later than the distal femur but earlier than the distal tibia.

Q: Tibial and common peroneal nerves supply which of the following muscles?

Biceps femoris. **Biceps femoris** - The **long head** of the biceps femoris is supplied by the **tibial nerve**. - The **short head** of the biceps femoris is supplied by the **common peroneal nerve**. *Gracilis* - The gracilis muscle is solely innervated by the **obturator nerve**. - It participates in **hip adduction** and **knee flexion**, but its innervation is distinct. *Adductor longus* - The adductor longus muscle is innervated exclusively by the **obturator nerve**. - Its primary function is **adduction of the thigh**. *Adductor magnus* - The adductor magnus has a dual innervation, but not by the tibial and common peroneal nerves. - Its **adductor part** is innervated by the **obturator nerve**, while its **hamstring part** is supplied by the **tibial nerve**.

Q: Which part of thalamus is related to motor control?

Ventrolateral thalamus. ***Ventrolateral thalamus*** - The **ventrolateral (VL) nucleus** of the thalamus is a key relay station for **motor control**, receiving input from the **basal ganglia** and **cerebellum** and projecting to the motor cortex [1]. - It plays a crucial role in the planning, initiation, and coordination of **voluntary movements**. *Ventral posteromedial* - The **ventral posteromedial (VPM) nucleus** is involved in processing **somatosensory information** from the face and taste sensations. - It does not primarily contribute to motor control pathways. *Ventral posterolateral* - The **ventral posterolateral (VPL) nucleus** relays **somatosensory information** from the body (limbs and trunk) to the primary somatosensory cortex. - Its main function is sensory perception, not motor control. *Lateral geniculate nucleus* - The **lateral geniculate nucleus (LGN)** is exclusively involved in the **visual pathway**, receiving input from the retina and projecting to the primary visual cortex. - It has no direct role in motor control.

Q: Which bone connects the sternum to the scapula?

Clavicle. ***Clavicle*** - The **clavicle**, or collarbone, is the only bone that directly connects the **axial skeleton** (via the sternum) to the **appendicular skeleton** (via the scapula). - It articulates medially with the **manubrium** of the sternum at the sternoclavicular joint and laterally with the **acromion** of the scapula at the acromioclavicular joint. *First rib* - The **first rib** articulates with the **manubrium** of the sternum but does not connect directly to the scapula. - Its primary role is to form part of the **thoracic cage**, protecting internal organs. *Manubrium* - The **manubrium** is the superior part of the **sternum** and articulates with the clavicles and the first two ribs. - It does not directly connect to the **scapula**; rather, the clavicle mediates this connection. *Second rib* - The **second rib** articulates with both the **manubrium** and the body of the sternum at the **sternal angle**. - Like the first rib, it is part of the **thoracic cage** and does not directly connect to the scapula.

Q: Masseter is supplied by which nerve?

Mandibular. ***Mandibular*** - The **masseter muscle** is a muscle of mastication, and all muscles of mastication are exclusively innervated by the **mandibular division** (V3) of the trigeminal nerve. - The mandibular nerve carries both **motor and sensory fibers**; its motor branches supply the masseter, temporalis, medial and lateral pterygoids, mylohyoid, anterior belly of digastric, tensor veli palatini, and tensor tympani. *Glossopharyngeal* - The **glossopharyngeal nerve (CN IX)** primarily supplies sensation to the posterior third of the tongue, the pharynx, and the tympanic membrane. - It also has motor functions, innervating the **stylopharyngeus muscle** and providing parasympathetic innervation to the parotid gland. *Facial* - The **facial nerve (CN VII)** is primarily responsible for innervating the **muscles of facial expression**. - It also carries taste sensation from the anterior two-thirds of the tongue and provides parasympathetic innervation to the lacrimal, submandibular, and sublingual glands. *Hypoglossal* - The **hypoglossal nerve (CN XII)** is exclusively a motor nerve. - It innervates all of the **intrinsic and extrinsic muscles of the tongue**, except for the palatoglossus muscle (which is innervated by the vagus nerve).

Q: Which structure connects Broca's area and Wernicke's area?

Arcuate fasciculus. ***Arcuate fasciculus*** - The **arcuate fasciculus** is a bundle of **association fibers** that connects the **Broca's area** (speech production) and **Wernicke's area** (speech comprehension) in the brain [1]. - Damage to this pathway can lead to **conduction aphasia**, where speech comprehension and production are relatively preserved, but repetition is severely impaired. *Fornix* - The **fornix** is a C-shaped bundle of nerve fibers in the brain that acts as the primary efferent (output) pathway of the **hippocampus**, a crucial structure for memory. - It carries signals from the hippocampus to the mammillary bodies and other subcortical structures, playing a key role in **episodic memory** and **spatial navigation**. *Anterior commissure* - The **anterior commissure** is a bundle of nerve fibers, located in front of the columns of the fornix, that connects the two **temporal lobes** and plays a role in pain sensation and memory. - It specifically connects parts of the **pyriform cortex** and **amygdalar nuclei** of the two hemispheres. *Corpus callosum* - The **corpus callosum** is a large, C-shaped nerve fiber bundle found beneath the cerebral cortex in the brain, connecting the **two cerebral hemispheres**. - It facilitates **interhemispheric communication**, allowing for the transfer of motor, sensory, and cognitive information between both sides of the brain [1].

Q: Dorsum of first webspace is supplied by which nerve?

Deep peroneal. ***Deep peroneal*** - The **deep peroneal nerve** innervates the **first dorsal webspace** of the foot, which is a classic sensory test area for this nerve. - Damage to this nerve can result in **foot drop** and loss of sensation in this specific area. *Superficial peroneal* - The **superficial peroneal nerve** supplies the majority of the **dorsum of the foot**, excluding the first webspace and the ankle. - It handles sensation for the **anterolateral aspect** of the distal leg and most of the dorsal foot. *Sural* - The **sural nerve** provides sensation to the **posterolateral aspect of the leg** and the **lateral border of the foot**. - It is often used for **nerve grafting** due to its superficial course. *Posterior tibial* - The **posterior tibial nerve** provides sensation to the **sole of the foot** via its medial and lateral plantar branches. - It also innervates most of the **intrinsic muscles of the foot**, affecting motor function.

Question 1

Which branch of facial nerve supplies muscles of lower lip

Accepted Answer

Marginal mandibular

Answer

Buccal

Answer

Cervical

Answer

Temporal

Question 2

Pointing index finger is seen in which nerve injury

Accepted Answer

Median

Answer

Axillary

Answer

Radial

Answer

Ulnar

Question 3

Hypoglossal nerve supplies all of these muscles except:-

Accepted Answer

Palatoglossus

Answer

Styloglossus

Answer

Genioglossus

Answer

Hyoglossus

Question 4

Secondary ossification centre appears before birth at

Accepted Answer

Lower end of femur

Answer

Upper end of femur

Answer

Lower end of tibia

Answer

Lower end of fibula

Question 5

Tibial and common peroneal nerves supply which of the following muscles?

Accepted Answer

Biceps femoris

Answer

Gracilis

Answer

Adductor longus

Answer

Adductor magnus

Question 6

Which part of thalamus is related to motor control?

Accepted Answer

Ventrolateral thalamus

Answer

Ventral posteromedial

Answer

Ventral posterolateral

Answer

Lateral geniculate nucleus

Question 7

Which bone connects the sternum to the scapula?

Accepted Answer

Clavicle

Answer

First rib

Answer

Manubrium

Answer

Second rib

Question 8

Masseter is supplied by which nerve?

Accepted Answer

Mandibular

Answer

Glossopharyngeal

Answer

Facial

Answer

Hypoglossal

Question 9

Which structure connects Broca's area and Wernicke's area?

Accepted Answer

Arcuate fasciculus

Answer

Fornix

Answer

Anterior commissure

Answer

Corpus callosum

Question 10

Dorsum of first webspace is supplied by which nerve?

Accepted Answer

Deep peroneal

Answer

Superficial peroneal

Answer

Sural

Answer

Posterior tibial

FMGE 2018 — Anatomy