Health Testing Information
In the year of 2000, the Health Committee of the Boston Terrier Club of America, sent out a Health Survey to all of its
members. They wanted to use the results of this survey, to come up with the top issues facing our Boston's today
and implement a program that would help to get these issues under control. Upon receiving the completed survey
back and compiling the information, it was determined that the 3 following Health Issues were at the top of the list of
concerns for Boston Terriers. So the Health Committee came up with a Program for all Boston Terrier Breeders to
follow that would help to alleviate these issues, for the betterment of the breed.
I have posted this information as a means to make the general public aware of the need to do selective breeding,
only using Dams and Sires that have passed these Health Testing requirements, in our breeding programs. I am
sure no one wants to purposely breed puppies that will be afflicted with these health issues, except for back yard
breeders who are only seeking to make a quick buck. Not only will these issues hinder the Boston in their daily lives,
making life quite unpleasant. And corrective surgery is quite costly to treat either the Cataract or Patella. I've heard
it is in the $3,000 range per eye/leg. I'd rather spare my puppies the pain and aggravation of these issues and
therefore not needing the corrective surgeries. Making for a healthier, happier, and hopefully longer life for both
owner and puppy to enjoy each others companionship.
Further References: Permanent Identification must be implemented prior to any testing.
Miscellaneous Web Sites:
BAER http://www.offa.org/deafbaer.html
CERF http://www.vmdb.org/cerf.html
OFFA http://www.offa.org/geninfo.html
CHIC http://www.caninehealthinfo.org
The following contains information on each of the individual tests:
BAER Hearing Exam:
BAER Test Sites may be located at http://www.lsu.edu/deafness/baersite.htm
The BAER (Brainstem Auditory Evoked Response) test needs to be performed only once in a dog’s life, after it is 35
days of age. OFA recommends this test should be performed by a Board Certified Veterinary Neurologist, but will
accept results from experienced veterinarians and audiologists.
Bilateral hearing PASSES. Unilateral or bilateral deafness FAILS.
The application fee is $15.00 per dog unless you qualify for the Litter Rate of $30.00 for 3 or more littermates.
Kennel Rate is $7.50 for 5 or more dogs owned by the same person.
Equivocal and affected dogs are registered at No Charge.
Examination protocol from the OFFA Web Site:
• BAER testing is done on canines at least 35 days old.
• A signal sound pressure level between 70 and 105 db is used to obtain a response with peaks I through V
judged present at their appropriate latencies.
• Insert earphones will be used.
• Chemical restraint is optional.
• The test is done in such a manner that movement will not cause an artifact that could be mistaken for a
response to a stimulus.
• At least 200 clicks will be used to obtain the response.
• A masking tone is not considered necessary if recordings are made with electrodes positioned along the
midline and in the ipsilateral mastoid region; a masking tone is necessary if the electrodes are placed along the
midline at the vertex and the T-1.
• Under appropriate circumstances when an ear tests as deaf using air-conducted stimuli, and the possibility of
conduction deafness exists (chronic otitis, excess ear wax accumulation), repeat testing with a bone stimulation
transducer is recommended.
• A printed copy of the BAER Test tracing will be provided to the owner and the OFA.
• The Printed copy of the BAER tracing must contain the dog’s name or identification linking it to this application.
CERF Exam Info
By Karen Graham, CERF Office Manager
A puppy can be CERF examined as early as five to eight weeks of age, depending on the breed and the
ophthalmologist. Drops are inserted into each eye to dilate the pupil for examination. Once the dog is CERF
examined, the owner sends a copy of the exam form to CERF for certification and we issue a CERF certificate if the
dog passes. Once we certify the dog, I submit the CERF results to OFA the first full week of the following month.
CERF Test Sites may be located at http://www.vmdb.org/clinic.html
Puppies can be examined as early as 8 weeks of age and CERF will also register them at that time. Send owners
copy of the physician completed CERF Exam form in with your $10.50 fee. Re-certification charge is $8.00.
Permanent Identification at time of exam of your dog (must be by microchip, tattoo or DNA profile) is required as of
1/1/01 to register your dog. Certification is good for 1 year from date of exam. Dogs should be CERF'd annually.
Patella Information
The Patella Examination form can be located at http://www.offa.org/plappbw.pdf
The Patella Examination is performed on dogs 12 months or older by your veterinarian and should be registered in
the Patellar Luxation Database with OFA. Puppies examined younger than 12 months will be treated as
Consultations and no OFA breed numbers will be assigned.
Fee for dogs over 12 months of age is $15.00. The Litter Rate of $30.00 applies to 3 or more submitted together.
The Kennel Rate of $7.50 applies to 5 or more submitted together, owned/co-owned by the same person. Patella's
should be re-examined bi-annually.
Patellar Luxation in Small Breed Dogs
by Teri Dickinson, DVM
Luxated patellas or "slipped stifles" are a common orthopedic problem in small dogs. A study of 542 affected
individuals revealed that dogs classified as small (adult weight 9 kg (20 lbs) or less) were twelve times as likely to be
affected as medium, large or giant breed dogs.(1) In addition, females were 1.5 times as likely to be affected.1 Some
researchers have suggested a recessive method of inheritance,(2),(3) and the higher incidence in females could
possibly be related to X-linked(4) factors or hormonal influences.
Luxated patellas are a congenital (present at birth) condition. The actual luxation may not be present at birth, but the
structural changes which lead to luxation are present. Most researchers believe luxated patellas to be heritable
(inherited) as well, though the exact mode of inheritance is not known. The condition is commonly seen in Italian
Greyhounds, although no published data regarding the incidence in IG's exists at this time. Researchers1 have
suggested that due to the high risk factor in toy breeds, breeding trials or retrospective pedigree analyses should be
undertaken by national breed clubs to answer some of these questions.
The stifle is a complicated joint(5) which is the anatomical equivalent of the human knee. The three major
components involved in luxating patellas are the femur (thigh bone), patella (knee cap), and tibia (calf or second
thigh). In a normal stifle, the femur and tibia are lined up so that the patella rests in a groove (trochlea) on the femur,
and its attachment (the patellar tendon) is on the tibia directly below the trochlea.
The function of the patella is to protect the large tendon of the quadriceps (thigh) muscle as it rides over the front of
the femur while the quadriceps is used to extend (straighten) the stifle joint. Placing your hand on your patella (knee
cap) while flexing and extending your stifle (knee) will allow you to feel the normal movement of the patella as it glides
up and down in the trochlea.
Luxation (dislocation) of the patella occurs when these structures are not in proper alignment.(6) Luxation in toy
breeds most frequently occurs medially (to the inside of the leg). The tibia is rotated medially (inward) which allows
the patella to luxate (slip out of its groove) and ride on the inner surface of the femur.
While the patella is luxated, the quadriceps is unable to properly extend the stifle, resulting in an abnormal gait or
lameness. In addition, the smooth surface of the patella is damaged by contact with the femur, rather than the
smooth articular (joint) cartilage present in the trochlea. With time this rubbing will result in degenerative joint disease
(arthritis). Furthermore, while the patella is luxated, the quadriceps puts a rotational force on the tibia, which over
time will increase the rotation of the tibia, thereby increasing the severity of the problem. The additional strain caused
by the malformation of the bones may also lead to later ligament ruptures. Many individuals are affected bilaterally
(both legs).
Signs of luxation may appear as early as weaning or may go undetected until later in life. Signs include intermittent
rear leg lameness, often shifting from one leg to the other, and an inability to fully extend the stifle. The leg may be
carried for variable periods of time. Early in the course of the disease, or in mildly affected animals, a hopping or
skipping action occurs. This is due to the patella luxating while the dog is moving and by giving an extra hop or skip
the dog extends its stifle and is often able to replace the patella until the next luxation, when the cycle repeats.
Several grades of luxation have been defined(7),5. In simple terms they are:
• Grade I. Patella can be luxated manually (by the examiner) but returns to the trochlea when released.
Occasional luxation occurs causing the animal to temporarily carry the limb. Tibial rotation is minimal
• Grade II. Patella can be easily luxated manually and remains luxated until replaced. Luxation occurs frequently
for longer periods of time, causing the leg to be carried or used without full extension. Tibial rotation is present.
• Grade III. The patella is permanently luxated, but can be replaced manually. The dog often uses the leg, but
without full extension. Tibial rotation is marked.
• Grade IV. The patella cannot be replaced manually, and the leg is carried or used in a crouching position.
Extension of the stifle is virtually impossible. Tibial rotation is quite severe, resulting in a "bow legged" appearance.
While no data has been published, personal observation reveals most affected IG's appear to have Grade I or II
luxations. I have also encountered puppies born with no trochlea and severe tibial rotation causing permanent
luxation from birth (Grade IV), and adult dogs so severely affected they were non-weight bearing in both hind legs
and merely dragged their rear legs along in a frog-like position (Grade IV).
Diagnosis is relatively simple for a veterinarian familiar with orthopedics. It involves palpation of the joint and manual
luxation of the patella. X-rays may also be used to determine the degree of rotation. Motivated owners may be
trained by veterinarians to palpate the stifles, but care must be exercised in order to avoid injuring the joint, or
making an incorrect diagnosis.
Diagnosis in severe cases may be possible at weaning, but in most cases the joints should be tight enough at 4 to 6
months(8) to allow reliable palpation. Screening of puppies at this age will help prevent large expenditures training
and showing dogs which later prove unsound. Screening of breeding stock and culling of affected individuals should,
over time, reduce the incidence of the condition.
Treatment involves surgical correction of the deformities. Many techniques are available depending on the severity
of the condition.(9) Satisfactory results are usually obtained if the joint degeneration has not progressed too far.
Once the condition is repaired, most affected individuals make satisfactory pets.
Bibliography
1. Priester WA: Sex, Size and Breed as Risk Factors in Canine Patellar Luxation. J Am Vet Med Assoc. 160:740,
1972.
2. Hutt FB: Genetic Defects of Bones and Joints in Domestic Animals. Cornell Vet. 58:104, 1968.
3. Kodituwakku GE: Luxation of the Patella in the Dog. Vet. Rec. 74:1499, 1962.
4. present on the X chromosome, of which females have two, XX and males one, XY
5. Miller, ME: Anatomy of the Dog. WB Saunders Co., Philadelphia, PA 1964.
6. Putnam RW: Patellar Luxation in the Dog. M.Sc. Thesis. Presented to the faculty of graduate studies, University of
Guelph, Ontario, Canada, January 1968.
7. Singleton WB: The Surgical Correction of Stifle Deformities in the Dog. J Small An Pract 10:59, 1969.
8. Archibald J: Canine Surgery. American Veterinary Publications, Santa Barbara, CA, 1974.
9. Brinker WO: Handbook of Small Animal Orthopedics & Fracture Treatment. WB Saunders Co., Philadelphia, PA,
1990.
This page last updated on 3-9-06.