• See Also
  1. Epiphyseal Fracture (Salter-Harris Fracture)
  2. Femoral Growth Plates
  3. Lower Leg Growth Plates
  4. Foot Growth Plates
  5. Humerus Growth Plates
  6. Hand Growth Plates
  7. Scapula Growth Plates
  8. Spine Growth Plates
  9. Forearm Growth Plates
  • Physiology
  • Bone Development from Cartilage
  1. Hyaline Cartilage
    1. Hyaline cartilage is the initial structure or mold into which bone forms
  2. Bone Collar
    1. Forms along the outer margin of the bone (at future diaphysis)
  3. Primary Ossification Center
    1. Hyaline cartilage deteriorates and cavitates centrally forming a hyaline cavity
  4. Medullary (central) spongy bone formation
    1. Spongy bone forms centrally from primary Ossification Center
  5. Periosteal Bud
    1. Vascular connective tissue from the perichondrium (outer margin) invades central hyaline cavity
    2. Forms future blood supply to Medullary cavity
  6. Medullary cavity
    1. Bony cavity replaces prior hyaline cartilage cavity
  7. Secondary Ossification Center
    1. Spongy bone forms from secondary Ossification Center (at each long bone end)
    2. Develops into epiphyseal bone
  8. Epiphyseal Plate cartilage (epiphysis or Growth Plate)
    1. Cartilage remains between bone formed from primary (central) and secondary (epiphyseal) Ossification Centers
    2. Remaining cartilage functions as a Growth Plate for Long Bone Growth
  9. Articular cartilage
    1. Hyaline cartilage remains at the long bone ends at joint margins
    2. All other hyaline cartilage is replaced by bone, aside from at the epiphysis
  • Physiology
  • Growth Plate (Physis)
  1. Long bones (e.g. femur, Humerus) in children contain 2 Growth Plates, one at each end
  2. Growth Plates are composed cartilage, which is in turn produced by chondrocytes
  3. Chondrocytes progress through 5 development stages, as they migrate from epiphysis to metaphysis
    1. See Growth Plate Layers below
  4. Growth Plate closure (fusion)
    1. Chondrocytes die
    2. Cartilage is replaced with mature bone (Endochondral ossification)
    3. Long Bone Growth ceases
    4. Growth Plate scar remains visible on XRay
  5. Growth Plate (Physis) blood supply
    1. Most of the Growth Plate perfusion is from the epiphysis
      1. First 2 Growth Plate layers (Resting and Proliferative Zones) are supplied by the epiphysis
      2. Hypertrophic zone is avascular compared with other layers
      3. Interrupted epiphyseal vascular supply to the Physis (Fracture) risk delayed Fracture healing and complications
    2. Other Growth Plate vascular supply
      1. Metaphyseal vessels (supplies endochondral ossification, region of cartilage replaced with bone)
      2. Perichondral ring of LaCroix (supplies the peripheral aspects of the Physis)
  6. Growth Plate closure
    1. Growth Plate closure is earlier in females
      1. Triggered by increased circulating Estrogen levels with Puberty
    2. Distal tibia and fibula Growth Plate closure
      1. Male: 14 to 19 years
      2. Female: 12 to 16 years
    3. Distal radius Growth Plate closure
      1. Male: 19 years
      2. Female 18 years
  • Anatomy
  • Growth Plate Layers (in the context of other bone regions)
  1. Articular cartilage of joint
  2. Epiphysis (rounded bone end)
  3. Epiphyseal Plate or Growth Plate (Hyaline Cartilage)
    1. Resting Zone (or Reserve Zone)
      1. Colloid matrix of vessels and germinal cells (chrondrocyte progenitors)
      2. Vessels (from the epiphysis) are the primary blood supply to the Growth Plate
      3. Chondrocytes differentiate from germinal cells, and remain in a resting state
    2. Proliferating Zone (or proliferative zone)
      1. Chondrocytes (formed in the reserve zone) undergo Mitosis after migrating to proliferating zone
      2. Chondrocyte organize into columns of a proteoglycan matrix
    3. Hypertrophic Zone
      1. Maturation Zone
        1. Chondrocytes further differentiate and increase in size throughout the Hypertrophic Zone
        2. Chrondrocytes also produce Collagen, glycogen, lipids and Alkaline Phosphatase
      2. Degenerative Zone
      3. Provisional Calcification Zone (or calcified zone)
        1. Least resistant to stress and greatest risk for Fractures
        2. Transition between calcified and non-calcified extracellular matrix Proteins
        3. Final layer of the Physis, in which colloid matrix calcifies and chondrocytes die
          1. Chondrocyte death allows for ostocytes to enter and osteogenesis begins
  4. Metaphysis
    1. Primary Spongiosa
    2. Secondary Spongiosa
  5. Diaphysis
  • References
  1. Sanghani, Kern and Mehta (2025) Crit Dec Emerg Med 39(2): 27-35
  2. Agirdil (2020) EFORT Open Rev 5(8):498-507 +PMID: 32953135 [PubMed]