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CHOCOLATE SHORKIES CAN
LOOK LIKE THIS
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Patella
laxation is also called loose knees. Most the time if your dog or puppy
has them the vet will grade it, The vet grades them from a
1-5, 1 being a little loose and 5 being the worst.
Toy
breeds are some of the most common breeds for this issue. That is why is
is so important that breeders have their adults tested and Registered
with the OFA showing their adults don't have this problem.
This is
a issue that can be congenital, or could also be how the puppy was
raised. If while the puppy is growing and maturing if they don't have a
solid ground to walk on this could cause Patella laxation. If this is
the case some times the knees can tighten when they get on solid ground.
But if
it is congenital they will most likely just get worse as they grow and
mature.
Below
you will see some great information about and explaining patellar
luxation.
USED with permission
Medial and lateral
patellar luxation
Dislocating kneecap, luxating patella, loose knee, trick knee
AffectedAnimals:
Dogs, cats, humans
Overview:
Patellar luxation can be a congenital condition or an
environmental condition in which the kneecap, or patella,
dislocates outside of its normal trochlear groove. Dislocation,
clinically referred to as luxation, can occur on either the
medial, or inside surface, or the lateral, or outside surface,
of the knee. There are varying degrees of patellar luxation that
are graded depending on whether the patella is intermittently or
constantly luxated. This abnormal displacement of the kneecap
results in pain, cartilage damage, and arthritis. There are
varying degrees of severity of this disease, and surgery may be
needed. |
Courtesy of: Gale Mueller
The knee on the left shows the normal position of the patella.
The center knee shows luxation of the patella to the medial
side. The knee on the right represents luxation of the patella
to the lateral side. |
It is much more common for the kneecap to ride
on the inside than on the outside surface of the knee. This condition
typically affects small and miniature breeds such as the poodle,
Pomeranian, Chihuahua, Schipperke, Bichon Frise, and pug. It is also
seen in the cocker spaniel, golden retriever, Labrador retriever, and
mixed breeds.
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- Patella
- Femur
- Patellar ligament
- Tibial Tuberosity
- Medial Luxation of Patella
- Lateral Luxation of Patella
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Outside dislocation of the kneecap, or lateral patellar luxation, occurs
more often in large breeds such as the Great Dane, Saint Bernard, and
Bernese mountain dog. Lateral luxation is often accompanied by
malformation of the femur, the large bone in the thigh. In these cases
the prognosis is more uncertain, as major limb reconstructive surgery
may be needed.Generally, the prognosis
is better when corrective surgery is performed early in the course of
the disease; many of the malformations in the bones and joint occur over
time and can be prevented with early correction.
Clinical Signs:
Lameness that is often intermittent, and may be unilateral or bilateral;
thick, swollen stifles; pain on range-of-motion; crepitus; palpable
luxation; inability to jump or walk normally; medial displacement of
quadriceps muscle group; lateral bowing of the distal third of the
femur.
Symptoms:
Intermittent or consistent lameness; bowlegged stance; reluctance to
walk or jump; occasionally holding a rear leg out to the side when
walking.
Description:
Medial patellar luxation, or MPL, is a very common disease of small and
miniature breeds in which the kneecap occasionally rides on the inside
of its normal groove. Primarily congenital, although occasionally
acquired through trauma, MPL causes lameness in one or both rear limbs.
The degree of lameness is determined by the severity and duration of the
disease, as well as the extent of existing arthritis.
Patellar luxation is graded on a scale
from I to IV, with IV being the most severe. The disease can progress
from the less severe to more severe grades over time. The more severe
forms are often accompanied by malformation of the femur and tibia, as
well as varying amounts of arthritis.
Dogs are frequently presented to a veterinarian
for intermittent lameness, often because it is becoming more frequent or
severe. When the patella, or kneecap, pops out of its normal trochlear
groove, the dog feels pain, and owners may report a hitch in the gait.
The dog will frequently extend the knee out from the body in order to
get the patella to pop back in to the trochlear groove. As MPL
progresses, the structures that hold the patella in place become looser,
and thus the problem becomes more frequent. This dislocation causes
pain, and as the frequency increases, so does the lameness.
Unfortunately, many of the severe Grade III or
IV cases go unnoticed for months or years because the affected animals
are usually miniature breeds that are often carried much of the time by
their owners. Their inability to jump or straighten out their hind legs
may go unnoticed because of their small size and sedentary lifestyle.
Lateral patellar luxation, or LPL, is less
common than MPL and occurs when the kneecap occasionally rides on the
outside of its normal groove. It, too, can be congenital or acquired,
with the congenital form again being more common. While it can occur in
any dog, it is more common in large and giant breeds. LPL is frequently
accompanied by malformation of the femur and/or tibia. The disease can
produce marked lameness and progress to crippling arthritis. Because of
the accompanying bony malformations, extensive surgery may be required
to correct this problem.
Diagnosis:
The examining veterinarian will often make a diagnosis from a physical
examination and history. However, x-rays are needed to determine the
degree of arthritis, and evaluate for any malformation of the femur and
tibia, the two major bones in the leg, which are joined together at the
knee.
Prognosis:
The prognosis for a Grade I patellar luxation is very good. These dogs
may not need surgery. However close observation for signs of worsening
is important. If surgery is indicated and performed early on, most
animals regain normal functionality.
The prognosis for Grades II and III
depends on how much arthritis and malformation have occurred. If caught
and treated early, both have a good to excellent prognosis. If there is
significant bony malformation or arthritis, the prognosis is guarded to
fair.The prognosis for Grade IV patellar
luxation is guarded. Most of these animals have moderate to severe bony
malformations and significant arthritis. If correction is performed, it
is important to initiate early physical therapy to help restore
function.
Transmission or Cause:
The congenital condition is probably genetic in
nature, and as such, affected animals should not be bred. Trauma or
injury can also cause patella luxation.
Treatment:
Treatment involves replacing the kneecap into the groove, and preventing
it from popping in and out. The following procedures can be used alone
or in combination as necessary to maintain the proper function of the
knee.
Imbrication
Tightening the joint capsule, known as imbrication, is done on the
opposite side of the luxation to prevent the kneecap from having enough
slack to pop out of the trochlear groove. Thus a medial patellar
luxation is treated with a lateral imbrication, and vice-versa.
Additionally, the joint capsule can be loosened on the side of the
luxation; this is called a release incision. This procedure relieves the
tension that the joint capsule is placing on the patella, thus allowing
it to ride in the trochlea.
In severe cases a synthetic suture is
sometimes necessary to keep the kneecap in place. This suture is placed
on the side opposite the luxation, and goes from behind the femur to the
patellar tendon. It also prevents the kneecap from popping over to the
other side.
Trochleoplasty
Deepening of the trochlear groove, or trochleoplasty, can be
accomplished with a variety of techniques. A chondroplasty technique
involves cutting out a taco-shaped wedge of cartilage, removing a small
portion of bone beneath it, and then replacing the cartilage. The
result is a deeper groove. This procedure can only be performed on
very young dogs, because their cartilage is thicker.
Trochlear recession involves cutting out
the cartilage and bone in such a way as to create a deeper trough. This
trough will then fill in with scar tissue over time. Because this scar
tissue is not as good as cartilage for joint function, this technique
has given way to others that attempt to preserve normal cartilage. It
can, however, be useful in carefully selected cases.
Wedge recession creates a taco-shaped piece of
cartilage and underlying bone. Then, the bone below the wedge is
removed and the wedge is replaced, forming a deeper groove. Block
recession is identical in principle to wedge recession, except that a
rectangular piece of cartilage and bone, rather than a wedge, is
removed.
Tibial Tuberosity
Transposition
The kneecap attaches to the lower leg via its patellar tendon at a bony
site called the tibial tuberosity. Many times this site forms
abnormally on the inside, as with MPL, or on the outside, as with LPL.
In this procedure, the surgeon moves the tibial tuberosity back into
proper alignment and secures it in place with a pin or wire. Realigning
the joint, kneecap, and tendon prevents dislocation from reoccurring.
Osteotomy
In severe cases, with malformation of the tibia or femur, corrective
bone cuts known as osteotomies may be required.
Prevention:
Early detection and correction is the best way to prevent severe
lameness and dysfunction. Breeding affected animals should be
discouraged; however, the disease is so prevalent in some breeds that
this may not be practical.
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1st generation 2nd
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PARTI
SHORKIES
CAN LOOK LIKE THIS
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