DisorderOsteoclast ActivityOsteoblast ActivityMineralizationKey Associations
Osteoporosis (Resorption) (Formation)NormalTrabecular thinning, Normal Labs
OsteopetrosisDysfunctional (Defective resorption)↔ / ↑NormalThick bone, Carbonic Anhydrase II mut.
Osteomalacia / Rickets↑ (Due to 2° PTH)↑ (Reactive)DefectiveUnmineralized osteoid, soft bone, ↓ Vit D
Paget Disease↑↑ (Lytic Phase)↑↑ (Sclerotic Phase)NormalMosaic pattern, woven bone, Isolated ↑ ALP
Osteitis Fibrosa Cystica↑↑ (PTH driven)NormalBrown tumors, Subperiosteal thinning