| Newsletter, 1999 |
Vol. 5, Issue 4 |
Practice Review
As we enter the end of the year, preparing to embark upon a new Millennium,
we will endeavor to highlight the major procedures we do in our practice.
Space limitations presented confine our subject material to the knee joint,
by far our most commonly operated-upon joint, and the reader is encouraged
to delve further into issues of interest utilizing available references.
Some reference material may be accessed through our website for those with
internet access. The topics of discussion are not presented necessarily
in order of importance or frequency. On average, we operate 5 to
7 knees per week!
1. Cruciate Ligament Injury
A general consensus among surgeons at the recent ACVS meeting is that
the occurrence of cranial cruciate ligament injury is becoming increasingly
prevalent. An ambitious multi-center study is currently underway
to do a prospective study of the incidence of cruciate ligament repairs
performed by surgeons in the private sector as well as university surgeons.
It seems that we are seeing certain breeds, such as the Labrador retriever
and the Rottweiler, incurring a greater frequency of this type of ligamentous
injury; a genetic propensity is suspected.
New surgical modalities for the treatment of the cranial cruciate-deficient
stifle joint show promise, but long-term studies are currently unavailable.
Arthroscopic repair, and the tibial plateau leveling osteotomy are currently
being critically evaluated. These techniques will probably ultimately
find a particular niche in our surgical armamentarium.
2. Medial Patellar Luxation Repair
Repair techniques for medial patellar luxation are relatively unchanged,
with the trochlear wedge recession sulcoplasty plus translocation of the
tibial tuberosity remaining the Gold Standard of repair techniques.
Preservation of articular cartilage has been shown to be far superior to
early surgical techniques which crudely gouged out a new groove in the
bone. Left to develop a fibrocartilage surface, this created a poor
substitute for the patella to glide upon compared to preservation of
the normal hyaline articular cartilage.
“Pulling” the patella laterally with sutures is no longer acceptable
technique. The tibial tuberosity translocation laterally has proven
biomechanically and physiologically to result in a more permanent realignment
of stress.
A question not addressed adequately in the literature is when
is the optimum time to repair a medial patellar luxation? Repair
of patellar luxation before closure of the distal femoral physis creates
the risk of iatrogenic damage to the growth plate and induced skeletal
deformity. Delay of correction after physeal closure may result in
further articular degeneration and subsequent progressive degenerative
joint disease (DJD). In this author’s opinion, the carefully performed
early surgical correction is preferred over delay until physeal closure.
3. Concurrent Patellar Luxation & Cruciate Ligament Rupture
Many times, medial patellar luxation is not noted until an acute lameness
is observed. It has been my experience in numerous cases that many
of these dogs have sustained an acute rupture of the cranial cruciate ligament.
This should always be evaluated when an acute non weight-bearing lameness
and concurrent medial patellar luxation are noted. The displaced
patella allows a disproportionate amount of the stress placed upon the
stifle joint to be borne by the cruciate ligament, and acute lameness seen
is usually the result of the cruciate ligament rupture, rather than the
chronic medial patellar luxation. Progression of DJD in these joints
can be expected to occur more rapidly than in those joints having only
medial patellar luxation.
4. Thank You!
To all of the veterinarians whom we have had the pleasure of getting
to know, we wish you a very Merry Christmas and a Happy New Year.
| Newsletter, 1999 |
Vol. 5, Issue 3 |
Pelvic fractures are a common injury in
both the dog and cat, often secondary to motor vehicle trauma. Management
of pelvic fractures can be complicated, depending on the bone or bones
involved, location of the fracture(s), and associated soft tissue injuries.
The vast majority of pelvic fractures are closed fractures, and are
not contaminated by exposure to the external environment. The initial management
in pelvic fracture cases is therefore geared towards patient stabilization
and evaluation of internal injuries. With the exception of acetabular fractures,
there is no hurry to fix the fracture before the patient is fully stabilized.
Of particular importance is evaluation of the urogenital tract, and of
the respiratory tract. Often, there is damage to the bladder or urethra
which needs to be evaluated, and the thoracic cavity should always be assessed
for diaphragmatic integrity as well as pulmonary contusions, pneumothorax,
etc.
Treatment of these injuries may range from open surgical management
to conservative cage rest.
During initial patient evaluation, rectal examination may indicate
pelvic fracture and the need for radiographic examination of the pelvis.
Rectal tears may be indicated by bright red blood on the exam glove, and
all digital exams should be done cautiously to avoid iatrogenic damage
to the rectum. Very few pelvic fractures result in full-thickness rectal
tears which require surgical intervention. Most tears involve the mucosal
layer and can be managed with antibiotic therapy.
Radiographs should include a lateral and VD view of the pelvis and caudal
lumbar spine.
The sciatic nerve should be evaluated, especially with caudal acetabular
fractures and markedly displaced SI luxations. The pudendal nerve to the
bladder should be assessed with sacrococcygeal fracture/luxation.
Many pelvic fractures can be managed conservatively, and economics may
dictate conservative management of fractures which would otherwise be better
handled surgically. Some general guidelines for conservative vs. surgical
management can be set forth:
Conservative Management
-
Fracture of the ischium (fractures caudal to the acetabulum).
-
Fractures of the pubis.
-
Relatively non-displaced sacroiliac (SI) luxations.
-
Most sacrococcygeal fracture/luxations.
Surgical Management
-
Any fracture cranial to the caudal acetabulum.
-
Fractures of the ilium.
-
Fractures of the acetabulum.
-
Unstable or displaced fracture/luxations of the sacroiliac joint.
Please note that the above listed injuries involve the weight-bearing portion
of the pelvis. Many animals over the years have been treated conservatively
who have had fractures that would be considered amenable to fixation. Reluctance
to offer a surgical alternative to conservative management has probably
been the result of lack of readily available instrumentation for fixation.
Most pelvic fractures require plate and screw fixation; instrumentation
and implants which are not cost-effective for many practices to maintain.
As an extension of the general practitioner, a surgical specialist can
offer fixation of many pelvic injuries in the dog and cat.
| Newsletter, 1999 |
Vol. 5, Issue 2 |
When Should I Refer a Case?
The following article is reprinted with permission from the author,
A..D. Elkins, DVM, MS, Dipl. ACVS
Over the past 28 years, I have been on both sides of this fence. I was
a general practitioner for 15 years and have been in a surgical referral
practice for the past 13 years. It is now easier and more widely accepted
to refer difficult cases. Legally, you are held to the highest standards
in your area. If you have a case that you know is outside your realm of
expertise, it is your duty to recommend referral. The owner may not choose
to follow through, but you have discharged your obligation.
Years ago, there were no specialists in private practice. All referrals
had to go to veterinary schools. Many times, it was difficult to get cases
seen and you might never hear about the outcome. University teaching hospitals
have been forced to do a better job due to the competition from private
referral practices. Yes, I said competition. No matter how you slice
it, we may be colleagues but each practice is in competition for your referral
business. Most veterinarians will refer cases to a practice, either private
or university, if several criteria are met. They want a user friendly practice.
This means they can speak to the clinician in charge of the case. They
want to be able to get a case seen on short notice. The clients must have
a positive experience and relay this to the referring practitioner. They
want to be kept informed! Many times, a case goes to a university and you
never hear back on it for several weeks. This is not acceptable since clients
depend on their family veterinarian for advice in these situations. Most
private practices do a much better job in communication because their business
depends on goodwill established with the general veterinarian.
Most large metropolitan areas now have referral groups that cover all
the medical disciplines. General practitioners should foster a working
relationship with an individual in each discipline. This will allow you
to consult and refer cases on an individual basis. In the future, secondary
level care will be delivered primarily at the local level by private groups.
Only cases requiring in-depth care such as radiation therapy will be referred
to the university or tertiary centers. The marketplace is driving this
phenomenon and will demand more in-depth care at the local level in the
future.
Many times, money is not the determining factor in whether a
client accepts a referral. It is convenience and the confidence the generalist
has in the referral specialist. Case referral is a symbiotic relationship.
Everyone should win in the situation. The animal should get the best care
possible, the generalist should have a convenient place to send difficult
cases or difficult clients and the specialist should enhance their referral
base. This only works if the communication lines are kept open.
When should you refer a case? When you feel the animal and client can
receive more advanced care than you are able to offer. It should be a practice
builder when cases are referred to the right individual. The specialist
should make you look good for sending the case. If this does not happen,
you may want to find another outlet for your referral cases.
__________________________
I would like to thank Dr. Elkins for allowing me to reprint this article.
It articulates the philosophy we have tried to adhere to, in making your
referrals a positive reflection on everyone involved. It is a pleasure
and a privilege to serve you and your clients.
__________________________
Please note on your calendar that our office will be closed Memorial
Day, May 31st. We are also going to be closed Tuesday and Wednesday, June
1st and 2nd. We will be back in the office on Thursday morning, June 3rd.
We will make arrangements to have the phone answered during the day, or
you may leave a message on the recorder. We will also try and schedule
non-critical cases in advance.
| Newsletter, 1999 |
Vol. 5, Issue 1 |
Patellar luxation, seen frequently in
the dog (especially miniature and toy breeds) is much less commonly encountered
in the cat. When luxation of the patella is seen in the cat, it is most
often a medial patellar luxation (MPL), and certain breeds seem to be more
prone than others to this condition.
In our practice, the most commonly affected breeds seem to be the Siamese,
Himalayan and Burmese. Also reported as being more frequently affected
with MPL is the Devon Rex.
The same criteria for grading luxation of the patella in the cat is
used as in the dog, i.e. the luxation is rated on scale of I to IV, with
grades II to IV luxations most commonly associated with lameness.
Diagnosis is most often made during physical examination. At the time
the patella is evaluated, the knee should also be examined for concurrent
injury to the cranial cruciate ligament, especially if an acute lameness
has been noted. The decision as to whether or not radiographs of the stifle
joints are needed should be made on a case-by-case basis. The hip joints
should be included in the radiographic projection on the ventrodorsal view.
Treatment varies depending on the severity of the luxation and the presence
or absence of concurrent cruciate ligament damage. Commonly performed as
mainstays of therapy are deepening of the trochlear groove, translocation
of the tibial tuberosity, imbrication of retinacular tissue and releasing
incisions to alleviate contracted tissues. Combinations of the above techniques
are utilized based upon the degree of correction required. An absolute
adage that must be adhered to is the tenet that "you cannot alleviate an
orthopedic abnormality with a soft tissue procedure". It must also be remembered
that, although patellar luxation is, by definition, a problem within the
stifle joint, the abnormality is in actuality a problem involving the entire
limb. Early work on medial patellar luxation in the dog suggests that the
abnormality may begin in the hip joint, resulting in abnormal forces acting
upon the patellar tendon-bone-ligament complex and producing the changes
recognized as medial patellar luxation in the stifle. This work may be
transposed to suggest the same etiology for MPL in the cat.
While not occurring as commonly in the cat as in the dog, medial patellar
luxation does occur and should be evaluated for when a hindlimb lameness
is found in a cat. Surgical correction is uniformly rewarding and should
be considered early in the course of the condition. I do not like to operate
animals younger than 6 months of age for fear of causing iatrogenic damage
to the physes. Delaying surgical correction can lead to corresponding changing
in the joint angles and bone structure which may be deleterious to long-term
limb function due to abnormal forces on the joints.
|