No announcement yet.

Cyclic loading, osteoporosis & tissue metabolism

This topic is closed.
  • Filter
  • Time
  • Show
Clear All
new posts

  • Cyclic loading, osteoporosis & tissue metabolism

    Hi All,

    I have found two (fairly old) references on the effect of cyclic
    loading on limb joint cartilage. I would guess that limb bones must show
    the same sort of adaptation to loading as the articular cartilage
    which is present at its ends - in fact naively I would expect the
    deposition of bone in response to loads of different frequencies to
    mirror the production of PGs in response to the frequency of
    articular joint contact loads. The papers are:

    Parkkinen JJ, Lammi MJ, Ikonen J, Helminen HJ and Tammi M (1992):
    The influence of cyclic hydrostatic pressure on cultured articular
    cartilage and chondrocytes. Paper given at the 19th Symposium of the
    European Society for Osteoarthrosis and Arthritis, Noordwijkerhout,
    the Netherlands, 24-27 May, 1992. WB van den Berg, of the University
    of Nijmegen was the chairperson of that session.

    Urban J and Hall A (1992) Physical modifiers of cartilage metabolism.
    Chapter 27 of "Articular Cartilage and Osteoarthritis", edited by K
    Kuettner et al., Raven Press Ltd, New York, pp 393-406

    Both these papers considered the effect of varying loading
    frequencies on PG production. I would surmise that if osteoporotic sufferers
    subjected their limbs to loading regimes that mimicked those known to keep
    articular cartilage cultures producing their maximal output of PGs, then their
    bones would also benefit greatly. Anyhow - its worth a trial!

    However its probably easier to keep chondrocytes and articular cartilage
    explants "happy" in vitro than bone, so I suppose that there have
    been very few studies of bone precipitation and removal, and the
    metabolism of osteocytes, -blasts and -clasts, in vitro (or for that
    matter, in vivo)? If someone knows of work similar to that
    referenced here, but for bone, I'd like to know, because I'm trying
    to develop a model to explain the adaptation of all the different
    Southern African antelope limb bones and joints to loading. (The
    advantage of antelope is that these are Eocene mammals having put in
    an appearance in the last 2,5 million years, and are still closely
    related. Some of the species in the same genus differ widely in
    mophology, but are still very closely genetically related - hence
    much of the difference betwen their limb bone structures and joints
    must be explainable on the basis of physical loading. I have a good
    model of how joints adapt to loading - but collecting and examining the
    physical evidence is daunting!)

    Mark W Swanepoel
    School of Mechanical Engineering
    University of the Witwatersrand

    To unsubscribe send UNSUBSCRIBE BIOMCH-L to
    For information and archives: