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Proceeding of the SEVC
Southern European Veterinary Conference
Oct. 17-19, 2008 – Barcelona, Spain
http://www.sevc.info
Reprinted in the IVIS website with the permission of the SEVC
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ORTHOPEDICS
Correction of Limb Deformities
Juan Pablo Zaera Polo
ULPGC
An angular deformity may be defined as the loss of the anatomical axisof a bone. Basically, there are
two possible causes of bone angulation: growth plate injuries (Salter-Harris V) or malunions.
Cierre prematuro de las líneas de crecimiento
The longitudinal growth of bones occurs at the growth cartilage by a process which is similar to
endochondral ossification.
At a certain age, depending on the breed and the particular plate, bones stop growing by “closing”their
growth plates. It is important to remember that although a growth plate may appear radiolucent in a
radiograph, this does not mean that the bone is active. Depending on the breed, growth may have
already ceased one or two months prior to being closed radiologically.
Aetiopathogenesis of premature closures
Premature closures normally occur as a result of a trauma affecting epi- ormetaphyseal vascularisation
leading to the death of cells responsible for the growth process.
The interruption of growth may have different consequences as a result of various factors.
-Patient age
The younger the animal, the greater the growth potential, so the growth retardation is more
pronounced.
-The growth plate affected
Depending on the growth plate affected, the functioning of the limb mayor may not be affected.
There are some growth plates that upon closing do not lead to any loss of functionality, for example
those of the tibial crest or the olecranon.
Others, however, affect the general bone length. In these cases, the functional impediment will depend
on the magnitude of the retardation. It is important to remember that when there is premature closure
of a growth plate,the bone compensates for this by increasing the growth activity of the plate in the
other metaphysis. Furthermore, the retardation of a limb may be perfectly compensated by increasing
the angle of the joint, thereby increasing the total length of the affected limb. A dog can compensate
for femur retardation of up to 25 % its length and retain a good quality of life.
Closure symmetry
Theproblem is aggravated when the closure only affects one part of the growth plate. In these cases,
the bone curves as it continues to grow on one side. This curvature normally interferes with the correct
anatomical functioning of the limb. Likewise, what often happens is that the curved bone alters the
amount of pressure on the articular surface. This may affect the growth plate of the other bone withwhich it is joined. A classic example is what occurs in the knee joint in patients with patellar luxation.
Treatment of premature closures
Given that the symptomatology that occurs due to premature closure appears gradually, it is important
that this is diagnosed as early as possible.
In paediatric animal cases with tarsus and carpus trauma with no apparent sequelae, we should alert
ownersto the possibility of injury to growth cartilage.
When dealing with a case of premature closure, we should firstly evaluate a series of different factors
Reprinted in IVIS with the permission of the SEVC Close this window to return to IVIS
Proceedings of the Southern European Veterinary Conference & Congreso Nacional AVEPA, 2008 - Barcelona, Spain
which would then guide us as to whichtreatment we should use.
Possible effects
As already mentioned, it is not always necessary to consider surgical treatment because the functional
consequences may often be compensated.
Growth potential
The younger the patient, the higher its bone growth potential. It is extremely important to remember
this, as the problems resulting from premature closure are more acute the further away the bones...