Hi Dr Deb, could you please explain a "periosteal strip". I've been told it is quite common but until yesterday had never heard of it. The person who told me about it could not explain it, she'd just been told that a prospective purchase had had it done as a youngster. Just the sound of it puts my teeth on edge.
You must be about to embark on your trip down our way. Happy travelling.
Jean, periosteal stripping is one of the best techniques that has ever come along for the surgical orthopedic correction of vargus/varus (bowlegged/knockneed) in foals.
Sometimes it is done as "stripping", i.e. actually surgically removing a thin strip of periosteum from one side of the upper end of the cannon bone, or else from the side of the distal radius-ulna, or both. In some cases, the surgeon prefers a technique whereby she merely abrades or "irritates" the periosteum in the appropriate area.
The object of this is to stimulate the bone cells that live under the periosteum to go to work making more bone. As you know, we say in class that the "dirty little secret" of all connective tissue cells is that they really want to be producing bone; and that all it takes to get bone cells to produce bone is to vibrate them, jerk on them, change the conditions of the gravity-field that they sense, send an electric current through them, pound on them, or scrape on them. Any of these "irritating" signals is interpreted by the bone cells as good cause to be producing more bone.
The object of surgically irritating the periosteum is to stimulate one side of the bones above and below the carpus to grow faster than the other side. In the case of knock-knees, the surgeon does this on the lateral side. When growth on the lateral side increases, it then will catch up and subsequently keep pace with the bone growth on the medial side. This has the effect of straightening out the knees.
The beauty of this surgery is that it is very little invasive, and is effective without negative sequelae when performed by a surgeon experienced in the procedure. It eliminates the need for bracing, casting, and pinning, all of which are very messy and dangerous in foals. The only downside is in permitting a surgeon with insufficient experience to perform it -- they have to know just where, and just how much, to irritate the periosteum in order to get good results. We do not, for example, want to stimulate the lateral side of knock knees so much that we wind up ultimately with a bowlegged horse.
So, although you might not like the sound of the name, this would be one book you wouldn't want to judge by its cover. Search online for more info and case histories, and you ought to join IVIS (http://www.ivis.org) -- non-veterinarians can be welcome there although you do have to present some credentials. It's a great library resource with full text of many papers, including a section on modern veterinary orthopedics.
Thank you very much Dr Deb. I just had an awful vision when I first heard of it and all my perioste(a) sort of shuddered! When I thought a bit about it I actually remembered our class discussions and it started to make sense. Your explanation (as ever) is very clear and it sounds fascinating and extremely worthwhile. I am a member of IVIS and will go digging there for more.
Thank you again. We are looking forward very much to seeing you next month