WHAT
IS A VETERINARY SURGICAL SPECIALIST?
Many
pet owners are unaware of specialization in veterinary medicine
although they are quite familiar with it in human medicine.
A specialist in veterinary medicine is quite similar to
the human counterpart, both having gone through additional
years of study and training to dedicate themselves to their
chosen area. As the human physician will refer patients
to a surgeon for complicated procedures, veterinary practitioners
often refer surgical cases to a veterinary surgeon.
The
American College of Veterinary Surgeons (ACVS) was formed
to acknowledge and regulate the training and certification
of veterinary surgeons. To achieve Diplomate status in the
ACVS, a veterinarian must complete at least four years (one
year of internship and three of a surgical residency) in
a program accredited by the ACVS. Upon completion of the
residency the candidate must submit credentials to the ACVS
for review. The credentials document the individuals
training including all the surgeries they have performed,
the Diplomate who supervised them, all class work done,
lectures given, and scientific papers published. If these
credentials are accepted, they are invited to sit for the
certifying exam. This is a two day exam consisting of oral,
written, and practical portions. Only upon successful completion
of all three parts do they attain the status of Diplomate
in the American College of Veterinary Surgeons. This is
a rigorous and time consuming process that ensures that
those achieving Diplomate status are fully qualified to
perform any and all types of specialized surgery that your
pet may require. Small animal surgery is typically divided
into three areas: orthopedics, soft tissue, and neurosurgery.
ORTHOPEDIC
SURGERY
Orthopedic
surgery involves bones, joints, muscles, tendons, and ligaments.
Fractured bones and torn ligaments are some of the most
common injuries seen by the veterinary surgeon. In many
cases, there are multiple injuries to the pet often as the
result of trauma. Advanced techniques including the use
of steel plates and screws or elaborate bone pin and clamp
systems are required to adequately stabilize these injuries
so that the pet can heal normally.
The
surgeon also sees more subtle, chronic injuries that can
be difficult to diagnose and frustrating to the pet owner.
Sporting dogs, like human athletes, may acquire these injuries
that though not debilitating, decrease their performance
in the sport. Often, however, these sporting dogs are stoic
and do not show their pain easily. A thorough orthopedic
exam, radiographs (x-rays), and specialized procedures may
be required to make the diagnosis in these complex cases.
Hip
Dysplasia
Of
course not all orthopedic problems are the result of injury.
Many pets are born with conditions that eventually cause
debilitating lameness. Hip dysplasia is a condition where
the hip joint is malformed resulting in a looseness or laxity.
This laxity leads to the development of arthritis. Hip dysplasia
is a well recognized condition that is widespread in many
breeds today. It can be heritable or passed on from generation
to generation, but heredity is only part of the problem.
Two parents with normal hips can produce a dysplastic puppy
though the chance is less than if one or both parents has
hip dysplasia. Do not ignore the signs of hip dysplasia
just because you were assured that your puppy would not
have it. The signs of hip dysplasia can include "a
bunny hopping" gait (both rear legs move forward together),
an obvious lameness, trouble getting up, and/or hesitancy
to jump or go up and down stairs. The diagnosis of hip dysplasia
is made with an orthopedic exam and radiographs (x-rays)
of the hips. Young dogs should be examined by a veterinarian
early as there are treatment options to prevent debilitating
arthritis. (see advanced techniques)
Osteochondritis
Dissecans (OCD)
Osteochondritis
dissecans (OCD) is another congenital abnormality which
can occur in any joint although it is most commonly seen
in the shoulder, elbow, stifle (knee), and hock (ankle).
Technically it is a failure of subchondral ossification
which in general terms means the cartilage of the joint
is not well attached and results in a loose flap of cartilage
in the joint. It can cause significant lameness and arthritis.
The treatment of choice is usually surgical removal of the
loose piece via arthrotomy (opening the joint) and arthroscopy.
The outcome depends on the joint or joints involved and
the degree of arthritis already present. The diagnosis is
made with radiographs (x-rays) and again early diagnosis
is beneficial.
The
elbow joint has several conditions besides OCD which can
occur in the young dog. These include fragmented coronoid
process (FCP), ununited anconeal process (UAP), and malalignment
of the joint surface. The first two, FCP and UAP, are similar
to OCD in that there is a loose fragment (in these cases
bone as well as cartilage) that causes lameness. The third
condition, malalignment, is where the joint surfaces of
the three bones that meet at the elbow (the humerus, the
radius, and the ulna) do not fit together. This may be because
either the radius or the ulna is growing too fast for the
other bone to "catch up". All of these conditions
can result in debilitating arthritis. They are diagnosed
by radiographs and surgery can be performed to correct the
problem or alleviate the pain if diagnosed early in the
disease process.
Other
growth deformities are seen in pets as a result of birth
defects or trauma to the young animal. Corrective surgery
should be performed to give the pet normal or near normal
use of the limb.
SOFT
TISSUE SURGERY
Soft
tissue surgery is a very broad category involving head and
neck surgery, cardiovascular (heart), pulmonary (lung),
gastrointestinal (stomach, intestine, liver, pancreas),
and urogenital (kidneys and bladder). The conditions in
each category may be either congenital (from birth) or acquired.
Acquired disorders are those not related to hereditary or
birth defects, and include trauma, infection and cancer.
Patent
Ductus Arterious (PDA)
Some
diseases cats and dogs are born with that require surgery
include heart and blood vessel problems such as patent ductus
arteriosus (PDA) and persistent right aortic arch (PRAA).
A PDA is a blood vessel that is present in the fetus that
should close down at or shortly after birth. If it stays
open, blood is shunted from one side of the heart to the
other overloading the system. The puppy or kitten will have
a heart murmur that can be detected on physical exam. They
often act quieter that normal and tire easily. The diagnosis
is made by detecting the murmur, radiographs of the chest,
and/or ultrasound exam of the heart. Surgery can completely
correct this condition. A thoracotomy (incision into the
chest cavity) is performed and the abnormal vessel is closed
off with suture material.
Persistent
Right Aortic Arch
A
persistent right aortic arch (PRAA) is the abnormal development
of blood vessels which results in a tight band constricting
the esophagus. The esophagus is the tube which brings food
from the mouth to the stomach. When the puppy or kitten
starts eating solid food, they will be unable to hold it
down for much of the time. The diagnosis is made by introducing
special dye into the esophagus and taking radiographs (x-rays).
To correct this, a thoracotomy is performed and the tight
band of tissue is removed, alleviating the obstruction.
It is important to do this surgery as early as possible
to prevent permanent damage to the esophagus.
Ectopic
Ureters
Another
congenital defect involves the urinary system and is called
ectopic ureters. The ureter is a tube that brings urine
from the kidney to the bladder. In the ectopic ureter condition
this tube does not empty into the bladder but instead goes
further out to the urethra or vagina. Pets with this condition
are often incontinent (leak urine), have urine scald around
their genitalia, and develop urinary tract infections. This
condition is also diagnosed with a special dye that identifies
the abnormal ureter. Abdominal surgery is performed and
the abnormal ureter is attached to its normal position in
the bladder. Once again, early diagnosis is beneficial.
Surgery
on pediatric animals requires specialized equipment, supplies,
and expertise. Heated surgery tables help patients maintain
body temperature, certain intravenous fluids are given to
stabilize blood sugar, anesthetic drugs are carefully selected,
and careful and complete monitoring of anesthesia are performed
to ensure a complete and speedy anesthetic and surgical
recovery. Once the young patient is awake from surgery recovery
is remarkable. Even chest surgery patients are eating within
one hour and dozing comfortably. They are often running
and playing within a week of surgery and would be even sooner
if they were allowed!
ACQUIRED
SOFT TISSUE CONDITIONS (TRAUMA/CANCER)
Acquired
soft tissue diseases or conditions are many and varied.
Pets may ingest inanimate objects that require surgery to
remove or they may suffer trauma requiring surgery such
as a ruptured spleen or bladder from being hit by a car.
Pets can get diseases like humans such as gallstones, kidney
or bladder stones, and stomach ulcers. Like their human
owners with these conditions, surgery is sometimes necessary.
Tumors
A
large part of soft tissue surgery is now oncological (cancer)
surgery. Cancer can and does occur in any part of the body
and can be either benign or malignant. The best test to
determine the type and nature (benign or malignant) of a
tumor is a biopsy where a portion or all of the tumor is
removed and sent to a pathologist for microscopic classification.
Benign
tumors may need to be removed if they are interfering
with the other neighboring body structures, enlarging dramatically,
causing discomfort, or are unsightly. If completely removed,
the benign tumor should not recur or spread to other body
areas. One example of a benign tumor is a lipoma or fatty
tumor that occurs anywhere, but is often seen and felt under
the skin in older pets. A simple aspirate using a small
needle to obtain a sample is usually adequate for diagnosis.
Surgical removal results in a skin incision that heals rapidly
and causes minimal discomfort for the pet.
Malignant
tumors often require a more aggressive approach and
additional therapy beyond surgery, including chemotherapy
or radiation. Surgery, however, is the main stay of many
cancer therapies and is often the only hope for a complete
cure.
Malignant
tumors can be deceivingly small in appearance and what can
be seen may only be the "tip of the iceberg".
It is therefore very important to be aggressive with surgery
making a wide surgical excision in an attempt to get rid
of all of the cancer. This may involve removing a portion
of the chest wall and ribs in cases of tumors of the thorax
(chest); removing half of the lower or upper jaw in the
case of oral (mouth) tumors; or amputating the limb in cases
of bony tumors of the limb. These may sound drastic but
are often essential for cure. The biggest mistake in oncological
surgery is to perform inadequate resection allowing the
cancer to recur. It may be more difficult or impossible
to completely remove at a second surgery, the cancer may
have spread to other areas in that time interval, and it
means a second surgery for the pet. The first chance is
the best chance for cure. Even aggressive (radical) surgery
in most pets is very well tolerated and can be very cosmetic.
Early intervention is the key to success!
ADVANCED
TECHNIQUES
Pain
Management
Whenever
surgery is performed, there is some postoperative pain.
The amount and duration varies with the type of surgery
and the condition of the patient. Although we cannot ask
the pets how they feel, we can and should assume it is similar
to humans. A spay is probably less painful than amputation
but both surgeries require addressing pain management (analgesia).
Pain
control starts before surgery is performed. We now know
that medicating prior to the onset of pain results in better
pain control with less total drug required. This is called
pre-emptive analgesia. All of our surgical patients receive
a premedication drug, the type and amount depending on the
level of expected discomfort. After surgery additional pain
medication is often required. This may be injectable and
given intermittently or on a slow intravenous dose. Oral
medications for pain is often prescribed for the first few
days to weeks at home.
An
important part of patient comfort is TLC postoperatively.
Providing warmed blankets and heating pads, a clean and
dry bed, and a good scratch behind the ears, go a long way
toward lessening their discomfort and anxiety.
Triple
Pelvic Osteotomy (TPO)
Hip
dysplasia is a condition where the femoral head and acetabulum
(the ball and cup) of the hip joint do not fit well together.
The cup or acetabulum is too shallow and the femoral head
or ball slips partially in and out as the dog walks. This
laxity or looseness of the hips can lead to debilitating
pain and arthritis.
The
triple pelvic osteotomy (TPO) is an orthopedic surgery performed
to lesson or eliminate the pain and arthritis in dogs with
dysplasia. As the name implies three cuts are made in the
bone of the pelvis and the bone is rotated usually 20 to
40 degrees so that the cup of the hip joint can cover or
capture the ball of the femur such that it can not slip
in and out. The cut pelvis is held in place at this angle
with a steel plate and screws while the bone heals, usually
in three to six weeks.
Hip
dysplasia usually involves both hips although one leg may
seem worse than the other. A triple pelvic osteotomy ideally
is performed on both hips. The operations are staged three
weeks apart to let the first side heal. Occasionally, but
rarely, they are done at the same time. Not infrequently
as few as 7 to 10 days may pass until the second hip is
operated on if the surgeon is concerned that arthritis might
develop if the second operation is delayed. If arthritis
is already present at the time of diagnosis this surgery
is not indicated as it is meant as prophylactic surgery
to prevent the development of arthritis.
Complications
are very rare but have been reported to include implant
failure (the plate pulls off or screws), infection, nerve
injury, and trouble urinating. These complications are usually
temporary or correctable.
Recovery
from the TPO is rapid. The dogs are often bearing weight
on the leg by the day after surgery and continue to improve
over a few weeks. They are restricted to leash walks for
3 weeks at which time radiographs (x-rays) may be made to
document healing. When healing of the bone is documented,
normal activity is resumed and the dog usually requires
no further therapy for pain management and lives a happy
pain-free life.
Arthritis
FHO/THR
Surgery
is not always performed early enough to prevent arthritis
and sometimes arthritis is inevitable either from one of
the aforementioned conditions or simply the result of age.
However it develops arthritis can be debilitating if left
untreated. Newer medicines are available that have a higher
potency and lower incidence of side effects to make arthritic
pets comfortable. Weight control and an exercise program
are key elements to successful arthritis management.
If medical management fails there are surgical options that
vary depending on the joint involved.
For
hip arthritis there is the total hip replacement (THR) surgery
or a femoral head and neck ostectomy (FHO). The THR is similar
to that performed on people where the whole joint is replaced
with metal and plastic components. It has a high success
rate and low incidence of complications. Even though both
hips often have arthritis it may be unnecessary to perform
hip replacement on both hips. Complications could include
infection, implant failure, and implant loosening. If they
occur the implants may have to be replaced or completely
removed. Fortunately this happens only rarely. The femoral
head ostectomy (FHO) involves the removal of the ball of
the hip joint and eventual formation of a "false"
or fibrous joint. Pain is eliminated by removing the bone
on bone contact that occurs in the arthritic joint. Often
both hips must have surgery to make the pet comfortable.
Both THR and FHO are considered salvage operations in that
the normal joint is replaced or removed. While this most
often tremendously improves the quality of life of the pet
it would be best to prevent its development. A triple pelvic
osteotomy (TPO) done early in a pets life can often
prevent debilitating arthritis and pain from developing
(see advanced techniques)
Arthritis
in other joints may also require salvage surgery if medical
therapy fails. Arthrodesis of a joint is a surgery where
the cartilage is removed and the bones are held together
with metal plates or pins until they fuse. This eliminates
the motion in that joint but takes all arthritis pain away.
Arthrodesis has been successfully performed in the shoulder,
elbow, carpus (wrist), stifle (knee), hock (ankle), and
toes.
Cancer
Surgery
Many
people balk when first discussing aggressive options for
malignant cancer. They are concerned about their pets
quality of life postoperatively and any deformity that may
result. Osteosarcoma is cancer of bone that often requires
amputation for the best outcome. Amputation of the limb
is well tolerated by both dogs and cats. They rapidly adjust
to bearing weight on the other three limbs and in a few
short days are more comfortable than they were before surgery.
Bone cancer pain in people is excruciating and we must assume
it is the same for animals. They dont understand their
pain and often sleep and eat less because of it. Simply
removing this source of pain can dramatically increase their
outlook and quality of life.
Osteosarcoma
can occur in the ribs as well, requiring removal. Chest
wall surgery is less obviously deforming than amputation
because the surgeon can remove up to 5 ribs and replace
the area with a plastic mesh which is covered by skin as
the incision is closed. When the hair coat grows back, the
defect is often not apparent. Recovery from surgery is again
quite rapid and full activity for the pet is resumed in
two to four weeks.
Oral
tumors (in the mouth) are common cancers requiring surgery.
The tumor types include squamous cell carcinoma (SCC), fibrosarcoma
(FSA), and melanoma. SCC and FSA can be cured with surgery
alone if diagnosis is early enough and surgery is aggressive
enough. Melanomas are aggressive tumors that have often
spread by the time of diagnosis but palliative surgery can
be performed. Palliative surgery is when surgery does not
cure the animal or increase their life span, but does improve
their quality of life. The
surgery involves removal of the portion of affected bone
with a "safety zone" of normal tissue removed
as well to ensure complete removal of the cancer. Almost
the entire lower jaw or three quarters of the upper jaw
can be removed although most tumors require far less, usually
involving one quarter of either upper or lower jaw. There
often is some cosmetic defect but when the hair grows back
it is often minimal. This is especially true in dogs whose
pendulous lip is often able to cover large defects. The
surgical recovery is again quite amazing as pets are usually
eating the next day.
Other
examples of cancer surgery include chest surgery to remove
lung cancer and abdominal surgery for liver, spleen, and
intestinal cancer. These leave no deformity other than a
small scar and the patient generally recovers rapidly.