Test #34 (BMR Week 3N Block 4: Ms)

Question 1

(1) Dx: 32 yo woman complains of weakness in her hands and “heaviness” in her eyelids at the end of each day. Chest imaging shows anterior mediastinal mass. (2) Identity & Origin of mediastinal mass (3) Other strx with same origin

Answer 1

(1) Mayasthenia gravis (2) Thymoma-Thymic hyperplasia from 3rd pharyngeal pouch (3) like inferior parathyroid glands (both of which obliterate)

Question 2

(1) Dx: 53 yo man presents with dull ache in right shouldder, pain worse with movement & often interferes with sleep, PE reveals localized tenderness just below acromion, patient asks to abduct his arms to 90 degrees and flex them to 30 degrees with thumbs pointing to floor & downward force to his arms elicits pain in patient’s right shoulder & reveals right-sided weakness as compared to left, Tendon of which muscle affected? (2) Explain

Answer 2

(1) Supraspinatus (2) Assits in abduction of arm and stabilization of glenohumoral joint; Most commonly injured structure in rotator cuff syndrome is tendon of supraspinatus muscle = vulnerable to injury due to impingement between acromion and head of humerus

Question 3

(1) Dx: 32 yo male presents to ER with sudden-onset heart palpitations, bp 100/70 mmHg, HR 160/min with regular rhythm (2) Maneuver recommended to patient & its purpose (3) Most important muscle for this maneuver & why

Answer 3

(1) Paroxysmal supraventricular tachycardia (2) Valsava maneuver Increases vagal & can be used to abolish paroxysmal SVT (3) Rectus abdominis most important muscle in achieving increased intraabdominal and intrathoracic pressure of Valvsava maneuver

Question 4

(1) Dx: 42 yo female complains of double vision while reading in evening, first noticed double vision several months ago, but her sx have worsened, also diff chewing & therefore avoids eating tough foods like steak, no extremity weakness or sensory complains (2) Pathophysiology/Molecular Outcome

Answer 4

(1) Myasthenia gravis (2) Autoimmune disease that results in decrease in ACh receptors on postysynaptic terminal of muscle end plate. This results in decreased ability of ACh to bind and open postsynaptic cation channels, thereby decreasing end plate potential

Question 5

(1) Dx: 70 yo man presents to physician because of bone pain. Serum ALP levels high, histologic exam reveals haphazardly-oriented, prominent cement lines that create a mosaic pattern of lamellar bone (2) Primarily abnormality in this condition

Answer 5

(1) Paget’s disease of bone (2) Increase in osteoclastic bone resorption

Question 6

(1) Dx/Explain: mother brings 1 mo. old son to ER because he appears “floppy” and has not been feeding well. Mother’s 43 yo multipara, family recently emigrated from E. Europe. PE shows mild jaundice, enlarged tongue, general hypotonia and umbilical hernia. (2) Importance of early dx

Answer 6

(1) Congenital hypothyroidism presents soon after birth with hypotonia, poor feeding, jaundice, macroglossia, constipation, and umbilical hernia (2) Dx ASAP to prevent development of mental retardation

Question 7

(1) Dx/Explain: 6 yo boy with hx of 5 bone fractures, 3 after only minimal trauma, 50th percentile for both height and weight since birth, reached developmental milestones, PE normal stature with small teeth, blue sclera (2) Mechanism

Answer 7

(1) Osteogenesis imperfecta: clinical findings - history of fractures after only minimal trauma, abnormal (blue) sclera, & small malformed teeth. in most patients, transmitted by autosomal dominant inheritance (2) Results from defective synthesis of type 1 collagen, Impairment of bone matrix formation results

Question 8

(1) Muscle spindle system v. Golgi tendon system functions (2) Which of these more likely to prevent body builder for holding lots of weight?

Answer 8

(1) Muscle spindle system: feedback system monitors and maintains muscle length; Golgi tendon system: feedback system monitors and maintains muscle force (2) GTOs exquisitely sensitive to increases in muscle tension but relatively insensitive to positive stretch

Question 9

(1) Deficient protein: Striated muscle fibers obtained from specific mouse embryo fail to contract in response to substance normally released from sarcoplasmic reticulum (2) Explain overall requirements for skeletal muscle contraction

Answer 9

(1) Troponin (2) Contractile mechanism in skeletal muscle depends on proteins (myosin II, actin, tropomyosin, and troponin) as well as calcium ions

Question 10

Dx/Explain: 46 yo gardener presents with knee pain, spends hours on knees several times per week while gardening.

Answer 10

Prepatellar bursitis: from repeated and prolonged kneeling; “Housemaid’s knee”, most common today in roofers, carpenters, and plumbers; S/Sx: knee pain, erythema, & irritability to knee on affected side

Question 11

7 Risk factors for Osteoporosis

Answer 11

(1) Smoking (2) Menopause (3) Corticosteroid therapy (4) Physical inactivity (5) Caucasian race (immutable, black females greater body mass than white females) (6) Low total body weight (7) Alcohol use

Question 12

Region of sarcomere with only myosin thick filaments

Answer 12

H band

Question 13

Artery associated with radial nerve

Answer 13

Deep brachial artery

Question 14

Dx/Explain: 45 yo Caucasian female presents to office with back pain, easy fatigability, & poor sleep, also complains of pain and stiffness in her muscle that’s worse after exercise. Physical examination reveals normal muscle strength and joint range of motion. Point tenderness elicted above scapular spine, lateral epicondyle, and medial fat pad of knee, bilaterally

Answer 14

Fibromyalgia: chronic disorder with unclear etiology that presents in women 20 to 50 years of age with diffuse musculoskeletal pain, insomnia, and emotional disturbances

Question 15

Identifying lunate on x-ray

Answer 15

More medial of 2 carpal bones that articulate with radius; Lunate medial to Scaphoid bone

Question 16

(1) Artery most likely damaged by femoral neck fracture & why (2) Complication of injury to this vessel

Answer 16

(1) Medial femoral cirmcumflex: provides majority of blood supply to femoral head and neck (2) Can cause avascular necrosis of femoral head

Question 17

Dx/Explain injury: 33 yo male slips while working in yard and falls on outstretch hands, right shoulder pain, flattening of right deltoid muscle and insensitivity of overlying skin to pinprick

Answer 17

Flattening of deltoid muscle after a shoulder injury suggests anterior shoulder dislocation. Injury most commonly results from forecful external rotation and abduction at shoulder joint. Axillary nerve injury, resulting in deltoid paralysis and loss of sensation over lateral arm, often associated.

Question 18

Digital clubbing: (1) common association/cause (2) conditions in which this is seen

Answer 18

(1) Often assoc. with prolonged hypoxia (2) Found in patients with large-cell lung cancer, tb, cystic fibrosis, and suppurative lung diseases such as empyema, bronchiectasis, and chronic lung diseases.