A Quick Look At: Leggs-Perthes
Also Known As:
Leggs-Calve-Perthes Disease, aseptic
or
avascular necrosis of the femoral head
Symptoms:
This disease is usually seen in young (under one
year old) toy and miniature breed dogs such as Miniature Pinschers and
Manchester Terriers, particularly Toy Manchesters. The clinical signs of
Leggs-Perthes usually occur between 4 months and one year, with the typical
range being between 6 and 9 months of age.
Normally, Leggs-Perthes consists of lameness in
one rear leg although it can occur in both rear legs and often appears shortly
after an injury. It can show as acute pain (dog cannot bear weight on one or
both hind legs) or as intermittent subtle lameness in one or both rear legs. The
pain may be mild to very severe. Some dogs have mild forms of this condition and
require minimal medical treatment. In other dogs, the condition causes
considerable pain and deformity of the hip joint and requires surgery. An x-ray
will confirm the presence of Leggs-Perthes. Muscle atrophy of the affected leg
is not uncommon. If the atrophy is severe, it can slow the recovery period
considerably and may make medical treatment less likely to work.
Cause:
Leggs-Perthes occurs when the bone that makes up
the ball portion of the hip is damaged from a lack of blood supply. The femur
head is no longer able to receive nutrients from the blood and the bone cells
begin to degenerate and die off. Eventually, the overlying cartilage may
collapse. It is not clear why this occurs. Since a higher incidence of
Leggs-Perthes is noted in several dog breeds, including terrier breeds,
Miniature Pinschers, Poodles and possibly Schipperkes, it is assumed that there
may be a genetic component to the disease. In Manchester Terriers, the genetic
component appears to be a strong influence and heritability is suspected to be
high. Several studies have indicated that Leggs-Perthes may have a multigenic
(more than one gene) means of inheritance, or that LP may not be completely
expressed. In other words, a Manchester may have the affected gene(s), but does
not show signs of Leggs-Perthes. More research needs to be done in this area.
