The Limping Mastiff
(Or When to Take Your Dog to the Veterinarian)
By Robin M. Smith, DVM
One of the main areas I get call regarding mastiffs is in the
orthopedic department. The pups are growing just fine and then they
start to limp. People want to know when they need to be concerned
enough to take the dog to the veterinarian. I cannot say I have a
magical time to take your dog to the veterinarian but I can try and
describe some common problems with mastiff puppies that I think all
should be aware of as conditions that can affect your mastiffs.
Developmental orthopedic conditions are a common cause of
lameness in our mastiff puppies, unfortunately. Many of the cases
have actually been present for several weeks, but the signs have
just been so subtle. There are familial, nutritional and inherited
components to many of these conditions. In the following paragraphs,
I will try to explain some of these conditions to you and when you
need to see the doctor.
Osteochondrosis is a developmental orthopedic condition in which
a disturbance in the normal process of bone development results in
thickening or retention of the articular cartilage on the end of the
bone. The long bones are the most frequently affected. This
thickened cartilage is prone to breaking off and if a cartilage flap
develops, inflammation and degenerative joint disease may result and
this condition is what is referred to as Osteochondritis dissecans.
Osteochondritis dissecans (OCD) occurs most frequently in rapidly
growing, male, large and giant breed dogs. Genetic, nutritional,
hormonal, and traumatic factors have all been implicated in the
process. The most common sites of occurrence are the hock, stifle,
elbow and shoulder joint.
In the hock, affected animals often develop clinical lameness by
four or five months old. Most dogs display consistent weight-bearing
lameness or intermittent non-weight bearing lameness. The affected
hock can be swollen and painful. The diagnosis can be made by
radiographing the joint.
In the stifle, OCD occurs infrequently. The affected dogs may
become lame as early as three months of age.
In the elbow, there are three conditions that can occur: ununited
anconeal process, osteochondrosis, and fragmented coronoid process.
In the shoulder joint, the story is a little different. Dogs
usually do not show clinical lameness until six months of age or
older. They may initially have mild, intermittent weight-bearing
lameness but can progress to intermittent non-weight bearing
lameness. In severely affected dogs, the shoulder muscles will
atrophy. Movement of the shoulder joint can be very painful.
The diagnosis of OCD is confirmed by radiographs. There are
certain locations of the various bones where these lesions are seen;
therefore the veterinarian has to be familiar with the correct
positioning of the dog to be sure to see the lesions. Once
diagnosed, surgery can correct the problem or at least alleviate the
The most common question I get about OCD is if it is inherited.
As stated before, this disease is multifactorial, being due to
nutrition, trauma, and hereditary causes. There is only one European
paper in the literature that supports OCD being totally hereditary.
Most other sources may suggest it is hereditary but cannot document
Panosteitis is an acquired inflammatory condition of unknown
cause that affects the long bones of large and giant breed dogs. It
affects males more than females, is often cyclic or recurrent, and
typically it is a shifting leg lameness. Lameness may be accompanied
by lethargy, fever, and loss of appetite. Pain is elicited when
pressure is applied to the affected region. This condition can also
be diagnosed by radiology. It shows up as a hazy appearance on the
inside of the bones.
Most of the time, all that is needed to get the dog through this
condition is strict confinement and aspirin therapy twice a day. The
dog WILL outgrow this.
This is a developmental disease of unknown cause that primarily
affects young, rapidly growing large and giant breed dogs. A genetic
basis for the disease has not been established.
Clinical signs may develop between two months of age and the time
of growth plate closure but typically manifest between two and four
months of age.
This condition is easily diagnosed by radiology.
Ununited Anconeal Process
UAP occurs in large and giant breed dogs. The clinical
abnormalities result from progressive degenerative joint disease.
Affected animals may exhibit lameness as early as four months. The
lameness is intermittent and may be exacerbated by exercise or
prolonged rest. Affected dogs may sit or stand with the carpus
(wrist) in a valgus position (bowing outward).
The diagnosis is confirmed by radiology. The fusion of the
anconeal process may not be done until 16 - 24 weeks of age, so a
diagnosis of UAP should not be made before 24 weeks of age.
Fragmented Coronoid Process
This condition affects the large and giant breed dogs also. The
cause of the condition is still controversial. A hereditary basis
for this condition has been suggested.
Clinical signs are rarely noted before five months of age. They
will develop. There will be lameness that is made worse by exercise
or prolonged rest.
A fragmented coronoid process is rarely
identified radiographically because of the superimposition of the
opposite coronoid process.
Hip dysplasia is the most common developmental
orthopedic condition that affects dogs. It is influenced by
genetics, environmental and hormonal factors.
Some dogs may have an acute onset of hind limb and hip pain, but
most dogs have more subtle clinical signs.
I am a proponent of nutrition being one of the causative factors
of these disorders. I am a strong advocate of getting your puppy off
the puppy food onto an adult dog food IF they are having problems,
but not before. Another factor that is important is the flooring
these puppies are on when young. It should be a good floor, which
allows the dogs to have good footing.
So, now what? What do I do if my puppy starts to limp? You need
to ask yourself various questions, i.e. Has your pup been
excessively exercising? If the answer is no... read on. If the
limping just started, make sure to examine the foot of the dog to
make sure there are no needles or burrs in it. I recommend confining
the dogs for 2 weeks and leash walk only. I also suggest aspirin 325
mg. (5 grain) for the inflammation.
If after two weeks, the limp is still there, or if after a few
days of confinement, the limping is worse, I recommend seeing a
veterinarian. Don't wait more than two weeks. All of our puppies can
overdo and hurt themselves very easily, so allow them time to get
over an injury that could have occurred, but DO NOT WAIT TOO LONG
I also will tell you to get the puppies off the puppy food or any
high protein food or any vitamins. These puppies are growing very
rapidly and we can slow this process down slightly. I recommend
putting them on 21-23% adult food. And again, make sure the pups
have good flooring for stability.
As you can see, unfortunately, because we love giant breed dogs,
we must be very aware of these orthopedic conditions because we can
try to alleviate some of the complications associated with these
If you have any specific questions on these conditions in your
mastiff, or, if you want to understand the different treatments for
these conditions please feel free to contact me.
Robin M. Smith, DVM
Westminster Veterinary Emergency/Trauma Center
269 W. Main St., Westminster, MD 21557