MSK SAS/Review Flashcards
A herniation of the L5-S1 space primarily affects the S1 nerve root, a primary component of the sciatic nerve, but would not affect the femoral or obturator nerve (L2-4). What muscle group of the lower limb would be least affected by this herniation?
A. Lateral compartment of the leg
B. Anterior compartment of the leg
C. Medial compartment of the thigh
D. Posterior compartment of the thigh
E. Deep posterior compartment of the leg
C. Medial compartment of the thigh (obturator nerve)
All other listed compartments are innervated by the sciatic nerve or the tibial or fibular branches of it
- Lateral leg = superficial fibular nerve
- Anterior leg = deep fibular nerve
- Posterior thigh = sciatic nerve
- Deep posterior compartment of the leg = tibial nerve
Citrullinated peptide (ACPA or CCP) is associated wtih which autoimmune disorder?
Rheumatoid arthritis
You are following a patient with psoriatic arthritis. Which of the following is NOT a feature consistent with this diagnosis?
A. Dactylitis
B. Nail pitting
C. MCP erosions
D. Pencil in cup deformity
E. Sacroiliitis
F. Enthesitis
C. MCP erosions
- MCP involvement more often seen in rheumatoid arthritis
- MCP usually spared in psoriatic
- Psoriatic usually involves DIP and/or PIP
Rickets is the inability to calcify which zone in the developing growth plate?
Identify the zone

B - Zone of hypertrophy
- A = zone of ossification
- B = zone of hypertrophy
- C = zone of proliferation
- D = resere cartilage
Which of the following histological sections shows elastic cartilage?

D

Where is atopic dermatitis most likely to present in toddlers?
Extensor surfaces
Which of the following opioid medications is most likely to cause side effects of itching and palpitations?
Why?
A. Fentanyl
B. Tramadol
C. Morphine
D. Hydrocodone
C. Morphine
- Morphine is the most likely opioid to cause histamine release
- This could lead to hypotension, tachycardia, urticaria, and pruitis
Between which layers in the hand is the midpalmar space located?
Between the flexor tendons and metacarpal bones

Which drugs are associated with drug-induced eczema?
Calcium chanel blockers
Consider in adults with new-onset eczema
Which of the following is a major driver of scleroderma pathogenesis?
- Microangiopathy with associated ischemic tissue injury
- Increased production of IL-1 from the inflammasome
- Oxidative stress of the endoplasmic reticulum
- Genetic defects in collagen cross-linking
- “Garbage disposal”. Hypothesis of accumulation of autoantibodies and subsequent complement activation through Interferon Gamma
a. Microangiopathy with associated ischemic tissue injury
Damage of the endothelium causes microangiopathy. As a part of healing, fibroblasts never fully shut off and continue to produce collagen and scar.
A cervical herniation at C5-6 will affect the musculocutaneous nerve. During physical examination, what difficulty would you expect to see in a such a patient?
Flexing the arm at the shoulder, flexing the elbow
What is the most appropriate treatment for acute gout?
Colchicine
- Depolymerized microtubules to prevent leukocyte migration
Note: Long-term management with probenecid to prevent an acute attack, but it will not treat an acute attack
Which of the following is a side effect of methotrexate?
A. Hypertension
B. Osteoporosis
C. Transaminitis
D. Progressive Multifocal leukoencephalopathy
E. Avascular Necrosis
C. Transaminitis (elevation of liver enzymes)
- Make sure you monitor in patients on methotrexate
A 35 year comes to your office with right foot weakness since her hospital stay 1 month ago. She says her right foot slaps when she walks quickly. On exam, she has weakness at the right ankle and loss of sensation at the first web space of the foot.
Which nerve is most likely affected?
Deep fibualr nerve
What substance lines the articular surfaces of bones in a synovial joint?
Hyaline cartilage
Note - there is no perichondrium on articular cartilage
(Perichondrium is the connective tissue that envelops cartilage when it is not at a joint)
Which blood test should you check before starting treatment with infiximab or adalimumab?
Why?
A. Hepatitis C
B. Quantiferon gold
C. JC virus
D. TPMT enzyme levels
B. Quantiferon gold
Check for latent TB infection
Both infliximab and adalimumab are anti-TNF-alpha agents. TNF-alpha plays an important role insequestering bacteria inside of granulomas to prevent systemic infection.
Loss of TNF-alpha can lead to reactivation of TB. Need to test before starting treatment to clear latent TB first
Anti SCL-70 (Anti Topoisomerase I) antibody is associated with which autoimmune disease?
Describe its presentation
Scleroderma
- Taut/thickened skin
- Stiffness and tightness in fingers; limited motion
- Raynaud phenomenon
- Difficulty swallowing
- Cough
Where is atopic dermatitis most likely to present in older children and adults?
Flexural distribution
(insides of joints)
Which cytokines are involved in the pathogenesis of systemic juvenile idiopathic arthritis?
IL-1, IL-6, and IL-18
Are these crystals characteristic of gout or pseudogout?

Gout
- Negatively birefringent
- Yellow when parallel to the polarizer
- Needle shaped
HLA B27 is associated with which condition?
Seronegative arthropathis (aka spondyloarthropatheis)
What kind of tissue is this?

Loose connective tissue
Which of the following is a major driver of the pathogenesis of systemic lupus erythematosis?
- Microangiopathy with associated ischemic tissue injury
- Increased production of IL-1 from the inflammasome
- Oxidative stress of the endoplasmic reticulum
- Genetic defects in collagen cross-linking
- “Garbage disposal”. Hypothesis of accumulation of autoantibodies and subsequent complement activation through Interferon Gamma
e. “Garbage disposal”. Hypothesis of accumulation of autoantibodies and subsequent complement activation through Interferon Gamma
This continues to drive the immune response
74 y/o comes in with unilateral calf pain with walking more than 3 blocks. Symptoms have been present for six months. Denies knee pain, numbness or tingling, or pain at rest. You decide to check an ankle-brachial index, which is abnormal.
Which of the following conditions is the most likely diagnosis?
A. Ruptured Baker’s (popliteal) cyst
B. Popliteal artery entrapment
C. Peripheral artery disease
D. Deep venous thrombosis
C. Peripheral artery disease
No symptoms at rest, symptoms with exertion = characteristic of PAD




















