Cartilage Matrix Degradation Disorders

name: Cartilage Matrix Degradation Disorders
display_name: Cartilage Matrix Degradation Disorders
creation_date: "2026-06-18T00:00:00Z"
description: >-
  Cartilage matrix degradation disorders are articular conditions whose
  pathophysiology includes chondrocyte stress, catabolic cytokine signaling,
  matrix-degrading enzyme activity, and progressive loss of cartilage matrix.
  The grouped entries differ in scale: one is a focal traumatic or overload
  lesion of knee cartilage, while the other is the diffuse whole-joint disease
  osteoarthritis.
grouping_basis:
- SHARED_MECHANISM
- SHARED_PHENOTYPE
grouping_rationale: >-
  Grouped on the shared osteoarthritis_cartilage_degradation module: members
  converge on articular chondrocyte stress and extracellular matrix loss. They
  are kept as separate Disease entries because a focal knee cartilage defect is
  a localized structural lesion with limited intrinsic repair capacity and risk
  of later OA, whereas osteoarthritis is a chronic, diffuse whole-joint
  degenerative disease involving cartilage, subchondral bone, synovium, and pain
  pathways.
membership_criteria:
- description: >-
    A disorder belongs to this grouping if and only if it conforms to the
    osteoarthritis cartilage degradation module, linking chondrocyte stress or
    catabolism to cartilage matrix loss and joint dysfunction.
  criteria_semantics: NECESSARY_AND_SUFFICIENT
  logic:
    criterion_predicate: CONFORMS_TO_MODULE
    module: osteoarthritis_cartilage_degradation
    description: >-
      Conforms to the osteoarthritis cartilage degradation module.
members:
- member: Focal Articular Cartilage Defect of the Knee
  member_type: DISEASE
  differentiating_mechanisms:
  - description: >-
      Localized full-thickness hyaline cartilage lesion, often from trauma or
      repetitive overload, whose mechanism starts at mechanical chondrocyte
      stress and impaired cartilage repair rather than established diffuse
      whole-joint degeneration.
    biological_processes:
    - preferred_term: response to mechanical stimulus
      term:
        id: GO:0009612
        label: response to mechanical stimulus
      modifier: INCREASED
- member: Osteoarthritis
  member_type: DISEASE
  differentiating_mechanisms:
  - description: >-
      Diffuse whole-joint degenerative disease with collagen and proteoglycan
      catabolism, low-grade inflammation, subchondral bone remodeling, pain,
      stiffness, and functional limitation.
    biological_processes:
    - preferred_term: collagen catabolic process
      term:
        id: GO:0030574
        label: collagen catabolic process
      modifier: INCREASED
notes: >-
  This grouping captures a final-common articular mechanism and deliberately
  spans one localized lesion and one diffuse disease because both entries
  declare conformance to the cartilage degradation module.