OITE Pure Memorization Cheat Sheet Flashcards

Comprehensive high-yield vocabulary flashcards generated from the OITE Pure Memorization Cheat Sheet covering basic science, genetics, bone biology, and anatomy.

Type I Collagen

Collagen found in bone, tendon, ligament, skin, scar tissue, and dentin; main collagen in bone, tendon, and meniscus.

Type II Collagen

Collagen found in articular cartilage, nucleus pulposus, and vitreous; main collagen in cartilage.

Type III Collagen

Collagen found in reticular fibers, skin, vessels, and granulation tissue; associated with early wound healing.

Type IV Collagen

Collagen found in the basement membrane (basal lamina).

Type V Collagen

Collagen found in cornea, placenta, and skin; associated with some Ehlers-Danlos syndromes.

Type X Collagen

Collagen localized to hypertrophic cartilage in the growth plate hypertrophic zone.

Aggrecan

The main proteoglycan in articular cartilage matrix, attached to a hyaluronic acid backbone.

Superficial Zone (Articular Cartilage)

Articular cartilage zone with parallel collagen orientation and flattened cells.

Deep Zone (Articular Cartilage)

Articular cartilage zone with perpendicular collagen orientation and columnar cells.

Osteoblast

Bone-forming cell originating from mesenchymal stem cells; marked by alkaline phosphatase, osteocalcin, Type I collagen, and P1NP.

Osteocyte

Mechanosensing bone cell derived from osteoblasts.

Osteoclast

Bone-resorbing cell originating from monocyte/macrophage lineage; marked by TRAP, cathepsin K, carbonic anhydrase, and CTX/NTX.

OPG (Osteoprotegerin)

Decoy receptor for RANKL that inhibits osteoclast activation and decreases bone resorption.

IL-8 / CXCL8

Pro-inflammatory cytokine responsible for neutrophil chemotaxis.

IL-10

Major anti-inflammatory cytokine.

BMP-2 / BMP-7

Growth factors that function in osteoinduction.

VEGF

Major growth factor responsible for angiogenesis.

Growth Plate Sequence (Epiphysis to Metaphysis)

Reserve zone -> Proliferative zone -> Hypertrophic zone -> Calcification zone -> Ossification zone.

PTHrP

Signaling factor that keeps chondrocytes proliferating and delays hypertrophy in the growth plate.

FGFR3

Receptor that inhibits chondrocyte proliferation; gain-of-function mutation causes achondroplasia.

PTH Bone Effects

Intermittent administration is anabolic (promotes bone formation); continuous administration promotes bone resorption.

Osteoporosis

Metabolic bone disease characterized by normal mineralization but decreased bone mass.

Osteomalacia

Metabolic bone disease characterized by defective bone mineralization; termed rickets in children.

Hypophosphatasia

Metabolic bone disease characterized by low alkaline phosphatase.

Osteogenesis Imperfecta

Genetic disorder caused by defects in COL1A1 or COL1A2 genes affecting Type I collagen.

Fibrous Dysplasia

Benign bone lesion/disease associated with GNAS gene mutation.

Ewing Sarcoma Genetics

Translocation t(11;22) involving EWSR1-FLI1 fusion.

Synovial Sarcoma Genetics

Translocation t(X;18) involving SS18-SSX fusion.

Myxoid Liposarcoma Genetics

Translocation t(12;16) involving FUS-DDIT3 fusion.

Giant Cell Tumor Genetics

Associated with mutation in H3F3A.

Li-Fraumeni Syndrome

Syndrome caused by TP53 mutation leading to osteosarcoma and multiple cancers.

Maffucci Syndrome

Condition characterized by multiple enchondromas and hemangiomas with risk of transformation to chondrosarcoma.

Primary Bone Healing

Bone healing occurring under absolute stability (e.g., compression plating) with minimal/no callus and direct osteonal remodeling.

Secondary Bone Healing

Bone healing occurring under relative stability (e.g., IM nail, bridge plating) characterized by callus formation via endochondral ossification.

Intramembranous Ossification

Direct bone formation where mesenchymal cells differentiate into osteoblasts without a cartilage template (e.g., flat bones).

C5 Nerve Root Motor Function

Shoulder abduction.

C6 Nerve Root Motor Function

Wrist extension.

C7 Nerve Root Motor Function

Elbow extension.

L4 Nerve Root Motor Function

Ankle dorsiflexion.

L5 Nerve Root Motor Function

Great toe extension.

S1 Nerve Root Motor Function

Plantarflexion.

Type I Muscle Fibers

Slow twitch, oxidative, fatigue-resistant endurance fibers with high mitochondria and myoglobin content.

Type II Muscle Fibers

Fast twitch, glycolytic power fibers that fatigue faster with fewer mitochondria and less myoglobin.

Enthesis

The graded transition zone of tendon insertion into bone consisting of tendon -> fibrocartilage -> mineralized fibrocartilage -> bone.

Nucleus Pulposus

Central intervertebral disc component rich in Type II collagen and proteoglycans, embryologically derived from the notochord.