Luxating Patellae
After one year of age, a Maltese should have their knees palpated and the results registered with the Orthopedic Foundation for Animals. This does not require anesthesia or x-rays. I recommend this be done by a veterinarian experienced in surgical repair of luxating patellae in toy breeds. A “tolerable” level of luxation for breeding is still up in the air. Since structure is genetic, breeding the most correct patellae possible is highly recommended. Using the OFA database to keep records can be extremely helpful when trying to produce a better Maltese.
Patellar luxation sometimes know as a slipped kneecap can be
result of injury or congenital defect.
Grades of Luxating Patella
Grade 1: Occasional carrying of the leg is seen, often
described as skipping or hopping, which may be transient, often returning to
normal by itself. Your veterinarian may easily luxate the patella manually and
return it to its normal position. Pain may be evident only when the knee cap
is luxated.
Grade 2: The frequency of luxation increases, becoming more
or less permanent. The dog will usually carry its leg, but will occasionally
bear weight on it. When palpated by the veterinarian, a dry, crackling
sensation (crepitation) may occur in the joint. A grade 2 luxation can
increase in severity, and if not surgically treated, can develop into
degenerative joint changes.
Grade 3: Permanent dislocation that occurs though weight
bearing may still be possible, however the stance will appear somewhat
crouching or bowlegged. Surgical intervention should not be delayed,
especially if this is found in a young, growing dog. Rapid growth of
abnormalities results in progressive deformities.
Grade 4: Permanent luxation, with the affected limb always
being carried, creates a bowlegged / crouching stance. Early surgery is
strongly recommended at this stage for bone deformities of the femur and tibia
may occur.
The cause is strongly suspected to be inherited but can also result from injury. All cases other than those resulting from trauma or injury are either known to be heritable.
Sources:
http://www.offa.org/patluxinfo.html
(OFA patella info) (OFA applications)Copyright © 2004 Everything Maltese