Osteopetrosis and Paget’s

 

Osteopetrosis vs. Paget’s Disease: NEET PG Comparison

Metabolic Bone Diseases: Skeletal Remodeling Disorders

1. Comparative Overview

Feature Osteopetrosis (Marble Bone) Paget’s Disease (Osteitis Deformans)
Pathology Defective osteoclasts; failure of bone resorption. Increased, disorganized bone remodeling (osteoclast/osteoblast).
Key Finding “Bone-in-bone” appearance; “Sandwich vertebrae.” “Cotton-wool” skull; “Picture-frame” vertebrae.
Biochem Usually normal (may have hypocalcemia). High ALP; Normal Ca/P.

2. High-Yield NEET Pearls

  • Osteopetrosis: Despite the increased bone density, these bones are brittle and fracture easily. Compression of cranial nerves leads to blindness and deafness.
  • Paget’s Disease Phases: Lytic → Mixed → Sclerotic.
  • Paget’s Risk: Increased risk of developing Osteosarcoma (the most dreaded complication).
  • Clinical Signs in Paget’s: Enlarging head size (needs a larger hat), bone pain, bowed limbs, and high-output heart failure (due to increased vascularity of bone).
  • Treatment: Bisphosphonates are the treatment of choice for symptomatic Paget’s disease.