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Dysplasia of the elbow. |
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Definition.
Dysplasia of the elbow is an irregularity of that joint when the young puppies are growing. It is one of the most frequent causes of lameness in the front leg. It actually covers three different types of condition: fragmentation of the medial coronoid process (FMCP), osteochondrytis dissecans of the medial humoral condyle (OCD), and the non-joining of the anconeus process (NJAP).
In layman’s terms all these diseases refer to the elbow joint and involve the incorrect coming together of the bone surfaces at the joint and/or the development of osseous excrescences in the areas where friction usually occurs. A dog affected by dysplasia of the elbow presents one or more of these conditions.
Clinical aspect.
Symptons
Whatever the disease in question (fragmentation of the medial coronoid process, osteochondrytis dissecans of the medial humoral condyle and the non-joining of the anconeus process), the animals affected are always young, growing dogs, and it sometimes occurs during the first few month of their lives. The symptoms are limping, the severity and duration of which can vary, occurring in episodes at different intervals, and aggravated by sustained exercise. There may also be passing stiffness when rising, which is reduced with activity and increased by intense exercise.
The limb is turned slightly outwards and held slightly apart. This disease is frequently bilateral. Pressure applied to the point can sometimes reveal swelling or pain. Manipulation of the elbow is painful, particularly when extending the limb in the case of fragmentation of the medial coronoid process and osteochondrytis dissecans of the medial humoral condyle, and during flexion in the case of the non-joining of the anconeus process.
The German shepherd, as with all rapidly growing breeds, is predisposed to dysplasia of the elbow in general. The breed would seem to be affected initially by the non-joining of the anconeus process, followed by fragmentation of the medial coronoid process. It is rarely affected by osteochondrytis of the medial humoral condyle, but diagnosis is difficult if the first two conditions are already present. Diagnosis
X-ray examinations are not always sensitive enough for detecting small fragments or minor modifications in the joint. Arthroscopy or arthrotomy can be used as a back-up when there is doubt over X-rays.
Other examinations, such as scanning or Magnetic Resonance Imaging, are useful for assessing lesions to the cartilage, but these are rarely used.
Treatment
The disease is systematically diagnosed in young animals, but the diagnosis often comes late. Treatment is mainly surgical in nature and the technique varies depending on the exact nature of the disease in question.
When surgery cannot be performed, palliative treatment will be used. This takes the form of administering anti-inflammatory and analgesic drugs, which limits the functional deficit, but is not able to correct the defective joint.
In all cases hygienic-measures is recommended. It is also necessary, in all cases, to prevent the animal from becoming overweight, to limit exercise and to opt for long, gentle exercise of jogging type rather than short intense exercise of the sprinting type.
Genetic aspects
Having become a focus of interest only recently, dysplasia of the elbow is still relatively unknown. Its exact origin has not been determined. It would seem that factors occur in combination: the development of the degeneration in the cartilage (osteochondrytis) and a poor joint. The means of transmission appears to be a system which includes several genes and the environment seems to play a not insignificant part. We thus speak of average inheritability, that is to say the environment accounts of half the occurrence of the disease. Different environmental factors have been examined. The fast growing breeds, such as the German Shepherd, are predisposed to it. There is a link between hip dysplasia and dysplasia of the elbow; the phenomenon of degeneration in the joint seems to be of a genetic origin and would thus constitute a risk factor. A hormonal effect is thought to explain why the male dogs are affected more than the females; testosterone is thought to stimulate growth and ossification, thereby increasing the speed of growth. Finally diet is an important factor: overfeeding, excessive calcium intake and vitamin C deficiency are to be avoided.
Dysplasia has not yet been officially placed on the list of defects to be eradicated. No eradication plans have been clearly formulated. However, given the genetics transmission of the disease, it is important not to use the most affected individuals for reproduction purposes.
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( with permission copied from the Royal Canin Encyclopaedia/Aniwa publishing) |
Only
recently has dysplasia of the elbow been studied properly. Many questions
remain unanswered, and in comparison with hip dysplasia, dysplasia of the
elbow remains an unknown. Nevertheless in the German shepherd 15-20% of
animals would seem affected. The males seem to be more frequently
affected than the females, as this occurs at an earlier age and more
seriously. Finally there would seem to be a correlation between hip
dysplasia and dysplasia of the elbow.
Diagnosis
is always through X-ray examination. Several X-rays from a number
of different angles are often necessary to obtain a clear picture of all
structures involved in this complex joint of the elbow. As in the case of
hip dysplasia, the age of the dog plays an important role. So it is not
possible to declare a dog free from the condition at too early an age. For
dysplasia of the elbow it is often advisable to wait 6-8 months.
Conversely, with regard to the non-joining of the anconeus process, which
occurs frequently in the German shepherd, there is a risk of wrongly
diagnosing dysplasia if the animal is too young and if reshaping in the
joint is slight. A final diagnosis cannot then be made until the age of 5
months.