The ultrastructure and biomechanical significance of the tidemark of articular cartilage. Academic Article uri icon


  • Thirty specimens of human articular cartilage obtained at surgery were examined by scanning electron microscopy to determine the ultrastructure of the tidemark, the junction of the non-calcified and calcified portions of mature articular cartilage. Three distinct variations of the collagen framework of the tidemark were observed: (1) A band of randomly oriented compacted fibrils that appeared to be continuous with those of the non-calcified and calcified zones. (2) A band of flattened fibrils paralleling the undulating surface of the calcified cartilage. (3) A band of perpendicularly oriented fibrils having a distinct continuous transition between the non-calcified and calcified zones, the amount of calcified material applied about the fibrils rapidly increasing as the fibrils entered the calcified zone. The tidemark may serve to provide a tethering mechanism for the relatively flexible and perpendicularly oriented collagen fibrils of the deepest portion of the non-calcified articular cartilage and may prevent them from being sheared at their point of anchorage to the calcified zone. The undulating pattern of the tidemark affords a strong geometric pattern in providing resistance to the shearing action of articulation. Small gaps present in the tidemark may provide pathways for the passage of nutrients into the deep non-calcified zone of articular cartilage from the subchondral bone.

published proceedings

  • Clin Orthop Relat Res

altmetric score

  • 6

author list (cited authors)

  • Redler, I., Mow, V. C., Zimny, M. L., & Mansell, J.

citation count

  • 152

complete list of authors

  • Redler, I||Mow, VC||Zimny, ML||Mansell, J

publication date

  • October 1975