A 27-year-old man presents to the emergency department with back pain. The patient states that he has back pain that has been steadily worsening over the past month. He states that his pain is worse in the morning but feels better after he finishes at work for the day. He rates his current pain as a 7/10 and says that he feels short of breath. His temperature is 99.5°F (37.5°C), blood pressure is 130/85 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 99% on room air. On physical exam, you note a young man who does not appear to be in any distress. Cardiac exam is within normal limits. Pulmonary exam is notable only for a minor decrease in air movement bilaterally at the lung bases. Musculoskeletal exam reveals a decrease in mobility of the back in all four directions. Which of the following is the best initial step in management of this patient?
Q2
A 71-year-old man with type 2 diabetes mellitus comes to the physician because of a 9-month history of pain and stiffness in the right knee. He reports that the stiffness lasts approximately 10 minutes after waking up and that the pain is worse in the evening. There is no history of trauma. He is 175 cm (5 ft 9 in) tall and weighs 102 kg (225 lb); BMI is 33 kg/m2. Examination of the right knee shows tenderness in the anteromedial joint line and crepitus during knee movement. Laboratory studies show an erythrocyte sedimentation rate of 15 mm/h and a serum uric acid concentration of 6.9 mg/dL. Which of the following is the most likely finding on imaging of the right knee?
Q3
A 45-year-old male alcoholic presents with fever, productive cough, and foul-smelling sputum for the past two weeks. Vital signs are T 38.3 C, HR 106, BP 118/64 and RR 16. Oxygen saturation on room air is 90%. Given a diagnosis of aspiration pneumonia, initial chest radiograph findings would most likely include:
Q4
A 65-year-old man is referred by his primary care provider to a neurologist for leg pain. He reports a 6-month history of progressive bilateral lower extremity pain that is worse in his left leg. The pain is 5/10 in severity at its worst and is described as a "burning" pain. He has noticed that the pain is acutely worse when he walks downhill. He has started riding his stationary bike more often as it relieves his pain. His past medical history is notable for hypertension, diabetes mellitus, and a prior myocardial infarction. He also sustained a distal radius fracture the previous year after falling on his outstretched hand. He takes aspirin, atorvastatin, metformin, glyburide, enalapril, and metoprolol. He has a 30-pack-year smoking history and drinks 2-3 glasses of wine with dinner every night. His temperature is 99°F (37.2°C), blood pressure is 145/85 mmHg, pulse is 91/min, and respirations are 18/min. On exam, he is well-appearing and in no acute distress. A straight leg raise is negative. A valsalva maneuver does not worsen his pain. Which of the following is the most appropriate test to confirm this patient's diagnosis?
Q5
A 41-year-old woman presents with back pain for the past 2 days. She says that the pain radiates down along the posterior right thigh and leg. She says the pain started suddenly after lifting a heavy box 2 days ago. Past medical history is irrelevant. Physical examination reveals a straight leg raise (SLR) test restricted to 30°, inability to walk on her toes, decreased sensation along the lateral border of her right foot, and diminished ankle jerk on the same side. Which of the following nerve roots is most likely compressed?
Q6
A 33-year-old man comes to the otolaryngologist for the evaluation of a 6-month history of difficulty breathing through his nose and clear nasal discharge. He has a history of seasonal atopic rhinosinusitis. Anterior rhinoscopy shows a nasal polyp obstructing the superior nasal meatus. A CT scan of the head is most likely to show opacification of which of the following structures?
Q7
A 52-year-old man is brought to the emergency department by a friend because of a 5-day history of fever and cough productive of purulent sputum. One week ago, he was woken up by an episode of heavy coughing while lying on his back. He drinks large amounts of alcohol daily and has spent most of his time in bed since his wife passed away 2 months ago. His temperature is 38°C (100.4°F), pulse is 96/min, respirations are 24/min, and blood pressure is 110/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 87%. Physical examination shows poor dentition and swollen gums. A CT scan of the chest is most likely to show a pulmonary infiltrate in which of the following locations?
Q8
A 45-year-old man is brought to the emergency department 30 minutes after falling off a staircase and hitting his head on the handrail. He was unconscious for 10 minutes and vomited twice. On arrival, he is drowsy. Examination shows a fixed, dilated left pupil and right-sided flaccid paralysis. A CT scan of the head shows a skull fracture in the region of the pterion and a biconvex hyperdensity overlying the left frontotemporal lobe. This patient's condition is most likely caused by damage to a vessel that enters the skull through which of the following foramina?
Q9
A 5-year-old girl presents to the physician with increased muscle cramping in her lower extremities after walking extended distances. The young girl is in the 10th percentile for height. Her past medical history is notable only for a cystic hygroma detected shortly after birth. Which of the following findings is most likely in this patient?
Q10
A 27-year-old man is witnessed falling off his bicycle. The patient rode his bicycle into a curb and hit his face against a rail. The patient did not lose consciousness and is ambulatory at the scene. There is blood in the patient's mouth and one of the patient's teeth is found on the sidewalk. The patient is transferred to the local emergency department. Which of the following is the best method to transport this patient's tooth?
Imaging/Clinical US Medical PG Practice Questions and MCQs
Question 1: A 27-year-old man presents to the emergency department with back pain. The patient states that he has back pain that has been steadily worsening over the past month. He states that his pain is worse in the morning but feels better after he finishes at work for the day. He rates his current pain as a 7/10 and says that he feels short of breath. His temperature is 99.5°F (37.5°C), blood pressure is 130/85 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 99% on room air. On physical exam, you note a young man who does not appear to be in any distress. Cardiac exam is within normal limits. Pulmonary exam is notable only for a minor decrease in air movement bilaterally at the lung bases. Musculoskeletal exam reveals a decrease in mobility of the back in all four directions. Which of the following is the best initial step in management of this patient?
A. MRI of the sacroiliac joint (Correct Answer)
B. CT scan of the chest
C. Pulmonary function tests
D. Ultrasound
E. Radiography of the lumbosacral spine
Explanation: ***MRI of the sacroiliac joint***
- The patient's symptoms of **worsening back pain**, morning stiffness that improves with activity, and decreased back mobility are highly suggestive of **ankylosing spondylitis**.
- **MRI** is the most sensitive imaging modality for detecting early inflammatory changes in the **sacroiliac joints** and spine, which are characteristic of ankylosing spondylitis, even before radiographic changes are visible.
*CT scan of the chest*
- While the patient reports feeling **short of breath**, his vital signs and oxygen saturation are normal, and he does not appear in acute distress.
- A CT scan of the chest would be a more appropriate step if there were clearer signs of acute pulmonary pathology, such as significant hypoxemia, fever, or adventitious lung sounds, which are not present here.
*Pulmonary function tests*
- **Shortness of breath** could eventually be a complication of severe ankylosing spondylitis due to restricted chest wall expansion.
- However, PFTs are generally not the *initial* diagnostic step given the primary presentation of back pain and the need to confirm the underlying rheumatologic condition first.
*Ultrasound*
- **Ultrasound** is not a primary imaging modality for evaluating the sacroiliac joints or the spine in the context of suspected ankylosing spondylitis.
- It could be useful for assessing peripheral joint inflammation in other arthropathies, but not for axial involvement.
*Radiography of the lumbosacral spine*
- **X-rays of the lumbosacral spine** might show changes in advanced ankylosing spondylitis (e.g., squaring of vertebrae, syndesmophytes), but they are often normal in the early stages of the disease.
- **MRI** is superior for detecting early inflammatory changes and is often used to diagnose the condition before radiographic damage is evident.
Question 2: A 71-year-old man with type 2 diabetes mellitus comes to the physician because of a 9-month history of pain and stiffness in the right knee. He reports that the stiffness lasts approximately 10 minutes after waking up and that the pain is worse in the evening. There is no history of trauma. He is 175 cm (5 ft 9 in) tall and weighs 102 kg (225 lb); BMI is 33 kg/m2. Examination of the right knee shows tenderness in the anteromedial joint line and crepitus during knee movement. Laboratory studies show an erythrocyte sedimentation rate of 15 mm/h and a serum uric acid concentration of 6.9 mg/dL. Which of the following is the most likely finding on imaging of the right knee?
A. Osteophytes and narrowing of the joint-space (Correct Answer)
B. Loculated epiphyseal cyst with thinning of the overlying cortex
C. Bony ankylosis and bone proliferation at the entheses
D. Marginal bony erosions and opacification of periarticular soft tissue
E. Periarticular osteopenia and pannus formation
Explanation: ***Osteophytes and narrowing of the joint-space***
- The patient's symptoms (age, knee pain worse in evening, short morning stiffness, obesity, crepitus, anteromedial tenderness) are classic for **osteoarthritis (OA)**.
- **Osteoarthritis** is characterized by the breakdown of articular cartilage, leading to bone-on-bone friction, resulting in **joint space narrowing** and the formation of **osteophytes** (bone spurs) at the joint margins, which are readily visible on imaging.
*Loculated epiphyseal cyst with thinning of the overlying cortex*
- This finding is more characteristic of a **chondroblastoma** or an **aneurysmal bone cyst**, which are typically seen in younger individuals and present with localized pain, swelling, and sometimes pathologic fractures, rather than the chronic, activity-related pain of OA.
- While subchondral cysts can occur in severe OA, a large, loculated epiphyseal cyst with cortical thinning is not the primary or most characteristic radiographic finding and would suggest a different etiology.
*Bony ankylosis and bone proliferation at the entheses*
- **Bony ankylosis** (fusion of joints) and **enthesitis** (inflammation and ossification at tendon/ligament insertions) are hallmark features of **spondyloarthropathies** like ankylosing spondylitis, not osteoarthritis.
- The patient's symptoms do not suggest an inflammatory arthritis (e.g., morning stiffness is 10 minutes, not hours, and ESR is normal).
*Marginal bony erosions and opacification of periarticular soft tissue*
- **Marginal bony erosions** (rat-bite erosions) and **periarticular soft tissue opacification** (due to monosodium urate crystal deposition) are characteristic findings of **gout**.
- While the patient has an elevated serum uric acid (6.9 mg/dL), this level is within the normal range for some labs and not definitively diagnostic of gout, especially without acute inflammatory flares or tophi. The chronic, activity-related nature of the pain is inconsistent with acute gout.
*Periarticular osteopenia and pannus formation*
- **Periarticular osteopenia** (bone thinning around the joint) and **pannus formation** (granulation tissue that erodes cartilage and bone) are characteristic features of **rheumatoid arthritis**.
- The patient's presentation (older age, pain worse with activity, short morning stiffness, no systemic inflammatory signs) is inconsistent with rheumatoid arthritis.
Question 3: A 45-year-old male alcoholic presents with fever, productive cough, and foul-smelling sputum for the past two weeks. Vital signs are T 38.3 C, HR 106, BP 118/64 and RR 16. Oxygen saturation on room air is 90%. Given a diagnosis of aspiration pneumonia, initial chest radiograph findings would most likely include:
A. Mediastinal abscess located between vertebral levels T1-T3
B. Left lung abscess due to increased ventilation-perfusion ratio of the left lung
C. Right lung abscess due to the right main bronchus being wider and more vertically oriented (Correct Answer)
D. Right lung abscess due to increased anterior-posterior diameter of the right lung
E. Left lung abscess due to the left main bronchus being located superior to the right main bronchus
Explanation: ***Right lung abscess due to the right main bronchus being wider and more vertically oriented***
- Aspiration pneumonia most commonly affects the **right lower lobe** because the **right main bronchus** is wider, shorter, and more vertically oriented than the left, making it a straighter path for aspirated material.
- Alcoholism is a significant risk factor for aspiration, and the clinical presentation of fever, productive cough, and foul-smelling sputum is classic for **post-aspiration bacterial infection** leading to an abscess.
*Mediastinal abscess located between vertebral levels T1-T3*
- A mediastinal abscess is a collection of pus in the **mediastinum**, usually resulting from esophageal perforation, infection spread from neck/pharynx, or surgery.
- While serious, it is not the typical initial radiographic finding in aspiration pneumonia, which primarily affects lung parenchyma.
*Left lung abscess due to increased ventilation-perfusion ratio of the left lung*
- While a lung abscess can occur in any lobe, aspiration preferentially affects the **right lung** due to anatomical differences in the bronchi, not primarily due to ventilation-perfusion ratios.
- An increased ventilation-perfusion ratio (V/Q) typically indicates areas of the lung are well-ventilated but poorly perfused (e.g., pulmonary embolism), which is not the primary mechanism leading to an aspiration abscess.
*Right lung abscess due to increased anterior-posterior diameter of the right lung*
- The anterior-posterior (AP) diameter of the lung is not a significant anatomical factor determining the preferential aspiration into the right lung.
- The key anatomical features are the **width and vertical orientation** of the bronchi.
*Left lung abscess due to the left main bronchus being located superior to the right main bronchus*
- This statement is anatomically incorrect; both main bronchi originate at the carina at approximately the same level, but the **right main bronchus** is wider, shorter, and more vertical in its orientation.
- The left main bronchus is actually longer and more horizontally oriented, making aspiration into it less common.
Question 4: A 65-year-old man is referred by his primary care provider to a neurologist for leg pain. He reports a 6-month history of progressive bilateral lower extremity pain that is worse in his left leg. The pain is 5/10 in severity at its worst and is described as a "burning" pain. He has noticed that the pain is acutely worse when he walks downhill. He has started riding his stationary bike more often as it relieves his pain. His past medical history is notable for hypertension, diabetes mellitus, and a prior myocardial infarction. He also sustained a distal radius fracture the previous year after falling on his outstretched hand. He takes aspirin, atorvastatin, metformin, glyburide, enalapril, and metoprolol. He has a 30-pack-year smoking history and drinks 2-3 glasses of wine with dinner every night. His temperature is 99°F (37.2°C), blood pressure is 145/85 mmHg, pulse is 91/min, and respirations are 18/min. On exam, he is well-appearing and in no acute distress. A straight leg raise is negative. A valsalva maneuver does not worsen his pain. Which of the following is the most appropriate test to confirm this patient's diagnosis?
A. Electromyography
B. Ankle-brachial index
C. Computerized tomography myelography
D. Magnetic resonance imaging (Correct Answer)
E. Radiography
Explanation: **Magnetic resonance imaging**
- **Magnetic resonance imaging (MRI)** is the most appropriate test for diagnosing **lumbar spinal stenosis** because it provides detailed imaging of soft tissues, including the **spinal cord, nerve roots, and intervertebral discs**.
- The patient's symptoms of bilateral lower extremity pain, worse with downhill walking and relieved by stationary biking (which typically involves a flexed spine), are classic for **neurogenic claudication** caused by spinal stenosis.
*Electromyography*
- **Electromyography (EMG)** measures electrical activity of muscles and can identify **radiculopathy** or **neuropathy** but does not directly visualize the spinal canal or its contents to diagnose the cause of nerve compression.
- While it could show nerve root involvement, it wouldn't be the primary diagnostic test to confirm **spinal stenosis** itself.
*Ankle-brachial index*
- The **ankle-brachial index (ABI)** is used to diagnose **peripheral artery disease (PAD)**, which can also cause leg pain with activity (**vascular claudication**).
- However, the patient's pain being worse with downhill walking and relieved by spine flexion (like on a stationary bike) is more consistent with **neurogenic claudication** than vascular claudication.
*Computerized tomography myelography*
- **CT myelography** involves injecting contrast into the spinal canal and then performing a CT scan. While it can visualize the spinal canal, it is more invasive than MRI and exposes the patient to **ionizing radiation**.
- It is typically reserved for cases where MRI is contraindicated (e.g., pacemakers) or when MRI findings are inconclusive.
*Radiography*
- **Radiography (X-rays)** can show bony changes such as **spondylosis** and **degenerative disc disease**, which are often associated with spinal stenosis.
- However, X-rays do not directly visualize the **spinal cord, nerve roots, or soft tissue compression**, making them inadequate for confirming spinal stenosis as the cause of neurogenic claudication.
Question 5: A 41-year-old woman presents with back pain for the past 2 days. She says that the pain radiates down along the posterior right thigh and leg. She says the pain started suddenly after lifting a heavy box 2 days ago. Past medical history is irrelevant. Physical examination reveals a straight leg raise (SLR) test restricted to 30°, inability to walk on her toes, decreased sensation along the lateral border of her right foot, and diminished ankle jerk on the same side. Which of the following nerve roots is most likely compressed?
A. Fourth lumbar nerve root (L4)
B. Second sacral nerve root (S2)
C. Third sacral nerve root (S3)
D. Fifth lumbar nerve root (L5)
E. First sacral nerve root (S1) (Correct Answer)
Explanation: ***First sacral nerve root (S1)***
- **Inability to walk on toes** (weakness of gastrocnemius and soleus), **decreased sensation along the lateral border of the foot**, and a **diminished ankle jerk** are classic signs of S1 radiculopathy.
- The radiating pain down the posterior leg, restricted straight leg raise due to a sudden onset after lifting, points towards a **disc herniation** compressing the S1 nerve root.
*Fourth lumbar nerve root (L4)*
- Compression of L4 typically causes **weakness in knee extension** (quadriceps), diminished patellar reflex, and sensory loss over the medial aspect of the shin.
- The patient's symptoms (inability to walk on toes, diminished ankle jerk) are not consistent with L4 nerve root involvement.
*Second sacral nerve root (S2)*
- S2 radiculopathy primarily affects sensation in the posterior thigh and calf and can cause **weakness in knee flexion** and **plantarflexion**, but the complete constellation of symptoms (especially ankle jerk reflex) is more indicative of S1.
- Isolated S2 compression without S1 involvement is less common with these specific signs.
*Third sacral nerve root (S3)*
- S3 nerve root compression typically presents with **perineal numbness** and issues with bowel or bladder function due to its involvement in these functions.
- The described motor and sensory deficits are not characteristic of S3 radiculopathy.
*Fifth lumbar nerve root (L5)*
- L5 radiculopathy is characterized by **weakness in foot dorsiflexion** (foot drop) and toe extension, leading to inability to walk on heels, and sensory loss on the dorsum of the foot.
- While L5 compression can cause radiating pain and a restricted straight leg raise, the specific deficit of **inability to walk on toes** and a **diminished ankle jerk** are not typical of L5 involvement.
Question 6: A 33-year-old man comes to the otolaryngologist for the evaluation of a 6-month history of difficulty breathing through his nose and clear nasal discharge. He has a history of seasonal atopic rhinosinusitis. Anterior rhinoscopy shows a nasal polyp obstructing the superior nasal meatus. A CT scan of the head is most likely to show opacification of which of the following structures?
A. Nasolacrimal duct and eustachian tube
B. Sphenoidal sinus and posterior ethmoidal sinuses (Correct Answer)
C. Frontal sinus and anterior ethmoidal sinus
D. Maxillary sinus and anterior ethmoidal sinus
E. Pterygopalatine fossa and middle ethmoidal sinus
Explanation: ***Sphenoidal sinus and posterior ethmoidal sinuses***
- The **posterior ethmoidal sinuses** drain directly into the **superior nasal meatus**, making them the primary structures affected by obstruction at this location.
- The **sphenoid sinus** drains into the **sphenoethmoidal recess**, which is located immediately posterior and superior to the superior nasal meatus. Due to their anatomical proximity and shared drainage region, obstruction in the superior meatus can affect drainage and lead to **opacification** of both structures due to **mucus retention** and inflammation.
- This is the most appropriate answer among the given options for superior meatus obstruction.
*Nasolacrimal duct and eustachian tube*
- The **nasolacrimal duct** drains into the **inferior nasal meatus**, not the superior meatus.
- The **eustachian tube** opens into the **nasopharynx**, which has no direct anatomical connection to the superior nasal meatus.
- These structures would not be affected by superior meatus obstruction.
*Frontal sinus and anterior ethmoidal sinus*
- The **frontal sinus** drains through the **frontonasal duct** into the **middle nasal meatus**.
- The **anterior ethmoid cells** also drain into the **middle nasal meatus** via the **infundibulum**.
- Obstruction in the **superior meatus** would not directly impact drainage of these sinuses.
*Maxillary sinus and anterior ethmoidal sinus*
- The **maxillary sinus** drains through its **ostium** into the **middle nasal meatus**.
- The **anterior ethmoid cells** drain into the **middle nasal meatus** through the **infundibulum**.
- These structures are not affected by superior meatus obstruction.
*Pterygopalatine fossa and middle ethmoidal sinus*
- The **pterygopalatine fossa** is a deep anatomical space containing neurovascular structures, not a sinus that drains into the nasal cavity.
- The **middle ethmoidal sinuses** drain into the **middle nasal meatus**, not the superior meatus.
- This option is anatomically incorrect for superior meatus obstruction.
Question 7: A 52-year-old man is brought to the emergency department by a friend because of a 5-day history of fever and cough productive of purulent sputum. One week ago, he was woken up by an episode of heavy coughing while lying on his back. He drinks large amounts of alcohol daily and has spent most of his time in bed since his wife passed away 2 months ago. His temperature is 38°C (100.4°F), pulse is 96/min, respirations are 24/min, and blood pressure is 110/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 87%. Physical examination shows poor dentition and swollen gums. A CT scan of the chest is most likely to show a pulmonary infiltrate in which of the following locations?
A. Posterior basal segment of the right lower lobe
B. Posterior basal segment of the left lower lobe
C. Posterior segment of the right upper lobe
D. Apicoposterior segment of the left upper lobe
E. Superior segment of the right lower lobe (Correct Answer)
Explanation: ***Superior segment of the right lower lobe***
- This patient presents with symptoms and risk factors (alcoholism, poor dentition, recent prolonged bed rest, coughing while lying down) consistent with **aspiration pneumonia**
- Aspiration pneumonia typically affects the superior segment of the lower lobes (especially the right) or the posterior segments of the upper lobes due to **gravitational flow of aspirated material when lying supine**
- The superior segment is the most posterior and dependent portion of the lower lobe in the supine position
*Posterior basal segment of the right lower lobe*
- While the right lower lobe is a common site for aspiration, the posterior basal segment is less common in a supine position where the superior segment is more dependent
- Aspiration into the basal segments (anterior, lateral, posterior) is more typical when a person is upright or in a semi-recumbent position
*Posterior basal segment of the left lower lobe*
- The right lung is generally more susceptible to aspiration than the left due to the **more vertical orientation of the right main bronchus**
- Similar to the right side, the posterior basal segment of the left lower lobe would be less commonly affected in a supine aspirator compared to the superior segment
*Posterior segment of the right upper lobe*
- The posterior segment of the right upper lobe is also a common site for aspiration when lying in a supine position
- However, the superior segment of the right lower lobe is the most frequently cited classic location for aspiration in the supine position
*Apicoposterior segment of the left upper lobe*
- Aspiration into the left upper lobe is less common than into the right lung due to the anatomy of the main bronchi
- The apicoposterior segment could be involved in aspiration, but the right lung and particularly the superior segment of the right lower lobe are statistically more probable
Question 8: A 45-year-old man is brought to the emergency department 30 minutes after falling off a staircase and hitting his head on the handrail. He was unconscious for 10 minutes and vomited twice. On arrival, he is drowsy. Examination shows a fixed, dilated left pupil and right-sided flaccid paralysis. A CT scan of the head shows a skull fracture in the region of the pterion and a biconvex hyperdensity overlying the left frontotemporal lobe. This patient's condition is most likely caused by damage to a vessel that enters the skull through which of the following foramina?
A. Foramen spinosum (Correct Answer)
B. Jugular foramen
C. Foramen lacerum
D. Foramen rotundum
E. Foramen magnum
Explanation: ***Foramen spinosum***
- The patient's presentation with a **skull fracture at the pterion**, a **biconvex hyperdensity** (classic for **epidural hematoma**), and rapid neurological deterioration (unconsciousness, fixed dilated pupil, contralateral paralysis) strongly indicates damage to the **middle meningeal artery**.
- The **middle meningeal artery** enters the skull through the **foramen spinosum** and is the most common vessel injured in epidural hematomas, especially with trauma at the pterion, as it lies directly beneath this thin part of the skull.
*Jugular foramen*
- The **jugular foramen** transmits the **internal jugular vein** and cranial nerves IX, X, and XI.
- Damage to vessels in this foramen would more likely result in issues such as **venous sinus thrombosis** or **cranial nerve palsies**, not an epidural hematoma with rapid mass effect.
*Foramen lacerum*
- The **foramen lacerum** is a jagged opening at the base of the skull, largely filled with cartilage, and traversed by the **internal carotid artery** on its superior aspect, as well as some small emissary veins and nerves.
- Injuries related to this foramen would typically involve structures like the internal carotid artery, leading to different clinical presentations such as stroke or hemorrhage into the pharynx, not an epidural hematoma.
*Foramen rotundum*
- The **foramen rotundum** transmits the **maxillary nerve** (V2), a branch of the trigeminal nerve.
- Damage involving this foramen would typically result in sensory deficits in the mid-face region, rather than the rapid neurological decline and signs of increased intracranial pressure seen in this patient.
*Foramen magnum*
- The **foramen magnum** is the largest opening in the skull, transmitting the **spinal cord**, vertebral arteries, and cranial nerve XI.
- Trauma affecting this region can lead to severe brainstem compression or spinal cord injury, but it is not typically associated with an epidural hematoma in the frontotemporal region or damage to the middle meningeal artery.
Question 9: A 5-year-old girl presents to the physician with increased muscle cramping in her lower extremities after walking extended distances. The young girl is in the 10th percentile for height. Her past medical history is notable only for a cystic hygroma detected shortly after birth. Which of the following findings is most likely in this patient?
A. Inferior erosion of the ribs
B. Barr bodies on buccal smear
C. Apparent hypertrophy of the calves
D. Endocardial cushion defect
E. Differential blood pressures between upper and lower extremities (Correct Answer)
Explanation: ***Differential blood pressures between upper and lower extremities***
- This patient's presentation of **muscle cramping** in the lower extremities after exertion (claudication), being in the **10th percentile for height**, and history of **cystic hygroma** is highly suggestive of **Turner syndrome** (45,XO).
- A common cardiovascular anomaly associated with Turner syndrome is **coarctation of the aorta**, which causes **higher blood pressure in the upper extremities** compared to the lower extremities due to narrowing of the aorta, typically distal to the left subclavian artery.
- This finding is the **classic clinical sign** on physical examination and would be present at any age when coarctation exists, making it the most likely finding in this **5-year-old patient**.
- The reduced blood flow to the lower extremities explains the muscle cramping with exertion (intermittent claudication).
*Inferior erosion of the ribs*
- **Rib notching** (inferior erosion) is indeed associated with **coarctation of the aorta** due to collateral circulation through dilated intercostal arteries.
- However, this is a **chronic radiological finding** that typically develops over many years and is more commonly seen in **older children and adults** with long-standing coarctation.
- In a **5-year-old child**, rib notching is **unlikely to have developed yet**, making differential blood pressures a more likely finding at this age.
*Apparent hypertrophy of the calves*
- **Calf pseudohypertrophy** is characteristic of **Duchenne muscular dystrophy**, a progressive X-linked recessive disorder typically affecting boys by age 3-5, caused by dystrophin deficiency leading to fatty and fibrous tissue replacement of muscle.
- While both conditions can present in childhood, this patient's **female sex**, history of **cystic hygroma**, and **short stature** point toward Turner syndrome rather than Duchenne muscular dystrophy.
*Endocardial cushion defect*
- **Endocardial cushion defects** (including atrioventricular septal defects) are classically associated with **Down syndrome** (Trisomy 21).
- While congenital heart defects are common in Turner syndrome (occurring in 30-50% of patients), **bicuspid aortic valve** and **coarctation of the aorta** are the most characteristic cardiac anomalies, not endocardial cushion defects.
*Barr bodies on buccal smear*
- **Barr bodies** represent an **inactivated X chromosome** and are visible in cells with at least two X chromosomes (e.g., normal XX females).
- **Turner syndrome** is characterized by **monosomy X** (45,XO), meaning there is only one X chromosome and thus **no Barr bodies** would be found on buccal smear.
Question 10: A 27-year-old man is witnessed falling off his bicycle. The patient rode his bicycle into a curb and hit his face against a rail. The patient did not lose consciousness and is ambulatory at the scene. There is blood in the patient's mouth and one of the patient's teeth is found on the sidewalk. The patient is transferred to the local emergency department. Which of the following is the best method to transport this patient's tooth?
A. Wrapped in gauze soaked in normal saline
B. Submerged in normal saline
C. Submerged in milk (Correct Answer)
D. Wrapped in sterile gauze
E. Submerged in water
Explanation: ***Submerged in milk***
- **Milk** is the ideal solution for transporting an avulsed tooth because it has a pH and osmolality that is compatible with the **vitality of the periodontal ligament (PDL) cells**.
- Its nutrient content also helps to sustain these cells, increasing the likelihood of successful **replantation**.
*Wrapped in gauze soaked in normal saline*
- While **normal saline** can keep the tooth moist, its osmolality is not optimal for maintaining the **viability of PDL cells** for an extended period.
- Wrapping in gauze may also cause the tooth to dry out if not kept adequately saturated, which can damage the **periodontal ligament**.
*Submerged in normal saline*
- Submerging in **normal saline** is better than dry storage but is still **suboptimal** compared to milk.
- The tonicity and pH of normal saline are not as beneficial for the **long-term survival of PDL cells** as milk.
*Wrapped in sterile gauze*
- **Sterile gauze** alone does not provide moisture or nutrients, leading to **rapid desiccation and death of PDL cells**.
- A dry environment dramatically reduces the chances of successful **replantation** and increases the risk of **ankylosis** or **resorption**.
*Submerged in water*
- **Water** is a **hypotonic solution** that can cause **lysis of PDL cells** due to osmotic pressure differences.
- This significantly compromises the tooth's viability and success of **replantation**.