Use the navigation bar above to access articles and more discussions on this topic.
| Author |
Message |
    
Robert N. Oglesby DVM
Moderator
Username: dro
Post Number: 20818
Registered: 1-1997
| | Posted on Tuesday, Jun 10, 2008 - 9:36 am: |   |
Some of the most interesting research being done today is how the horses musculoskeletal system develops from birth. We can expect the findings of such research to help elucidate the mechanisms of developmental orthopedic diseases that are so common in growing horses. Recent research has been looking at the possibility that early forced exercise, in moderation, may strengthen joints, tendons, and ligaments making older horses more resistant to break down. Here is a small study that did not find an effect on improved articular cartilage when comparing exercised foals to pastured foals. Of course it is not the end of this aspect as other exercise regimens may improve or degrade articular cartilage quality.
DrO
Osteoarthritis Cartilage. 2007 Nov;15(11):1283-92.
Variations in articular calcified cartilage by site and exercise in the 18-month-old equine distal metacarpal condyle.
Doube M, Firth EC, Boyde A.
Biophysics, Oral Growth and Development, Queen Mary University of London, London, United Kingdom. m.doube@qmul.ac.uk
OBJECTIVES: To interrelate articular calcified cartilage thickness, mineralisation density, tidemark count and tidemark linear accretion rate by site in the equine third metacarpal distal condyle. To determine the effects of exercise during early life on articular calcified cartilage. METHOD: Six of 12 pasture-raised Thoroughbred horses were exercised from 10 days old. Calcein labels were given 19 and 8 days prior to euthanasia at 18 months old. Osteochondral specimens were cut from the distal third metacarpal condyle and imaged using confocal scanning light microscopy (CSLM) and quantitative backscattered electron scanning electron microscopy (qBSE). Articular calcified cartilage thickness and total thickness mineralisation density were measured on montages base image sets, and inter-label mineralisation density, tidemark count and linear accretion rate measured on registered CSLM-base image pairs. RESULTS: Calcified cartilage thickness, mineralisation density, tidemark count and linear accretion rate varied significantly between sites. Regions with thinner calcified cartilage had greater linear accretion rates, hence rapid chondroclastic resorption. Mineralisation density was positively correlated with linear accretion rate. Fewer multiple tidemarks were counted in regions with greater linear accretion rates. Lag time between the tidemark and cement line was estimated (180 days; in the range of 0-648 days). Exercise had little effect on measured parameters. CONCLUSION: The major determinant of articular calcified cartilage thickness is the rate of chondroclastic resorption, not tidemark linear accretion rate. Our evidence supports coupled, mechanosensitive regulation of chondroclastic resorption and linear accretion rate in articular calcified cartilage. Exercising pasture-reared foals causes little additional adaptation in distal third metacarpal articular calcified cartilage. |
