Exam Corner

Pathology

Prepared by Mohamed Sukeik
SICOT Associate Member & SICOT Newsletter Editorial Board Member - London, United Kindgom

 

Questions

 


 

  1. RANK Ligand is a molecule which is implicated in a variety of degenerative bone diseases and bone metastasis and exerts its effects by binding to:

    1. Osteoclasts

    2. Osteoblasts

    3. Osteocytes

    4. Osteoprogenitor cells

    5. Lining cells
       

  2. During fracture healing bone blood flow increases as part of the regional acceleratory phenomenon and peaks at:

    1. 1 day

    2. 3 days

    3. 7 days

    4. 14 days

    5. 30 days
       

  3. World Health Organization defines osteoporosis as a:  

    1. Lumbar density level 3.5 standard deviations below the peak bone mass of a 25-year-old individual

    2. Lumbar density level 2.5 standard deviations below the peak bone mass of a 35-year-old individual

    3. Lumbar density level 2.5 standard deviations below the peak bone mass of a 25-year-old individual

    4. Lumbar density level 2.5 standard deviations below the peak bone mass of a 50-year-old individual

    5. Lumbar density level 3.5 standard deviations below the peak bone mass of a 50-year-old individual
       

  4. Joint fluid analysis of which of the following conditions shows: 2,000-75,000 white blood cells (WBCs) with up to 50% polymorphonuclear neutrophil leukocytes (PMNs); moderately decreased glucose (25mg/dl lower than serum glucose); low viscosity, yellow-green friable mucin clot?

    1. Non-inflammatory arthritides

    2. Inflammatory arthritides

    3. Infectious arthritides

    4. Hemorrhagic arthritides

    5. Neuropathic arthropathy
       

  5. The most common cause of upper-extremity neuropathic arthropathy is:

    1. Diabetes

    2. Tabes dorsalis

    3. Syringomyelia

    4. Hansen's disease

    5. Myelomeningocele
       

  6. The most common joint affected in juvenile rheumatoid arthritis is the:

    1. Shoulder

    2. Elbow

    3. Wrist

    4. Hip

    5. Knee
       

  7. Osteoid osteomas are characterised by all of the following, except:

    1. Occurs most commonly in 30-50 years age group

    2. Pain that responds to salicylates

    3. May produce scoliosis

    4. Radiographs show intensely reactive bone and a radiolucent nidus

    5. Responds in 90% of cases to radiofrequency ablation
       

  8. The most common type of osteosarcoma is:

    1. Parosteal

    2. Periosteal

    3. High-grade intramedullary

    4. Telangiectatic

    5. Sarcoma associated with Paget’s disease
       

  9. Osteosarcoma in children and young adults most commonly occurs about the:

    1. Humerus

    2. Knee

    3. Hip

    4. Pelvis

    5. Spine
       

  10. Prognostic factors that adversely affect survival in osteosarcomas include all of the following, except:

    1. Expression of P-glycoprotein

    2. High serum alkaline phosphatase

    3. High lactic dehydrogenase

    4. No alteration of DNA ploidy following chemotherapy

    5. The presence of antishock protein 90 antibodies after chemotherapy

Answers

 

  1. a
    Discussion: Osteoblasts and tumour cells express the RANK Ligand, which is a molecule that binds to receptors on osteoclasts, thus increasing bone resorption. 
    Reference: Review of Orthopaedics, Miller

  2. d
    Discussion: During fracture healing bone blood flow increases as part of the regional acceleratory phenomenon and peaks at approximately 2 weeks.
    Reference: Review of Orthopaedics, Miller

  3. c
    Discussion: World Health Organization defines osteoporosis as a lumbar density level 2.5 standard deviations below the peak bone mass of a 25-year-old individual.
    Reference: Review of Orthopaedics, Miller

  4. b
    Discussion: Non-inflammatory arthritides: 200 WBCs with 25% PMNs; glucose and protein equal serum values; normal viscosity (high), straw color, firm mucin clot.
    Inflammatory arthritides: 2,000-75,000 WBCs with up to 50% PMNs; moderately decreased glucose (25mg/dl lower than serum glucose); low viscosity, yellow-green, friable mucin clot.
    Infectious arthritides: >80,000 WBCs with > 75% PMNs; a positive Gram stain and later on positive culture, moderately decreased glucose (25mg/dl lower than serum glucose); opaque fluid, increased synovial lactate.
    Neuropathic arthropathy (Charcot joint disease) is a non-inflammatory arthritides caused by disturbed sensory innervation.
    Reference: Review of Orthopaedics, Miller

  5. c
    Discussion: Diabetes → Foot
    Tabes dorsalis → Lower extremity
    Syringomyelia → Most common upper-extremity cause
    Hansen’s disease → 2nd most common upper-extremity cause
    Myelomeningocele → Ankle and foot
    Reference: Review of Orthopaedics, Miller

  6. e
    Discussion: The most common joint affected in juvenile rheumatoid arthritis is the knee joint.
    Reference: Review of Orthopaedics, Miller

  7. a
    Discussion: It is most commonly seen in young patients aged 5-30 years.
    Reference: Review of Orthopaedics, Miller

  8. c
    Discussion: High-Grade intramedullary osteosarcoma is also called ordinary or classic osteosarcoma. It is the most common type of osteosarcoma and most commonly occurs about the knee in children and young adults. Other common sites include the proximal humerus, proximal femur and pelvis. Patients present primarily with pain.
    Reference: Review of Orthopaedics, Miller

  9. b
    Discussion: High-Grade intramedullary osteosarcoma is also called ordinary or classic osteosarcoma. It is the most common type of osteosarcoma and most commonly occurs about the knee in children and young adults. Other common sites include the proximal humerus, proximal femur and pelvis. Patients present primarily with pain.
    Reference: Review of Orthopaedics, Miller

  10. e
    Discussion: The absence of antishock protein 90 antibodies after chemotherapy adversely affects survival in osteosarcomas.
    Reference: Review of Orthopaedics, Miller