A NOVEL therapy that helped the
world’s richest sportsman, Tiger
Woods, to resume his golf career
following a knee injury is now
available in the UK to dogs
suffering from osteoarthritis.
Jeffrey Schaffer,
director of the animal
health division of the US
medical equipment
company Pall Life
Sciences, told British veterinary
surgeons about its development of a
filter system for extracting platelets
from canine and equine blood. The
platelet enriched plasma can then be
injected directly into the joint, where it
has been shown to be useful in
treating both cartilage and ligament
injuries, he said.
Dr Schaffer and his fellow US
veterinarian Professor Alicia Bertone,
an equine orthopaedic surgeon from
Ohio State University, were invited to
address audiences of small animal
clinicians by VBS Direct, which has the contract to import and distribute
Pall’s veterinary products in the UK.
Based in Long Island, New York State, Pall is one of the world’s leading
suppliers of filtration technologies for a range of industries from human
health care to the food and drink
sector. Its latest product, C-Pet, is
believed to be the first commercial
venture into the small animal market
by a company in the emerging field of
regenerative cell therapy.
Activated platelets are known to
release around 30 different cellular
growth factors, as well as a range of
anti-inflammatory cytokines which
have been shown to accelerate healing
of damaged joint tissues. The
technique has been used by US equine
practitioners to treat around 4,000
horses, mainly for suspensory
ligament injuries, and the results have
been very encouraging, he said.
The filter system was developed
for use by clinicians working in
ambulatory clinics to treat horses in
the field. It is a single use, disposable
unit which will produce a therapeutic
quantity of plasma with around three
times the base level concentration of
platelets ready for use without further
processing.
Sample from jugular vein
A sample of around 55ml of blood can be taken from the jugular vein and
injected into the entry tube for the
filter which can be held manually or
suspended from an intravenous
infusion stand. The platelets bind
selectively to a special filter while the
majority of the other blood cells pass
through and are discarded.
The platelets are then collected in
a proprietary harvest solution and a
quantity of 1.5 to 5ml, depending on
the size of the dog, is injected directly
into the affected joint.
Professor Bertone described the
results of trials using this technology
in 20 client-owned dogs with
osteoarthritis affecting a single joint
(see also the Marie Fahie study
mentioned on the previous page of
orthopaedic abstracts).
On examination 12 weeks after a
single treatment, there were significant
improvements in lameness and pain
scores, as assessed by the owners and
referring veterinarian, and a
substantial improvement in the peak
maximum force generated by the affected limb on a pressure plate.
Any fluid left over after the first treatment can be frozen and used later
for a second treatment. This may be
particularly valuable in those dogs
where it is not immediately clear
which joint is the source of the
lameness in a particular limb, Dr
Schaffer noted.
However, once defrosted, the
plasma would have to be used
immediately. Like the centrifugation
process used previously to concentrate
platelet cells, thawing causes activation
of the cells and the release of the
cytokines contained in the cytoplasm.
Less invasive
Prof. Bertone believes that platelet
treatment will be appealing to both
veterinarians and dogs’ owners as a
much less invasive technique than
some of the surgical alternatives such
as joint replacement.
“Subjectively, the filter-based
device used to obtain the platelet
concentrate … was easy to use, and
the entire procedure from initial
sedation to completion of the intra-
articular injection took about 30
minutes.
“Although the study found
significant effects at 12 weeks after
treatment, further studies are needed
to determine the optimal dose and the
duration of effect,” she notes in her
paper published in the Journal of the
American Veterinary Medical Association (November, p1,291).
The US’s most successful golfer is not the only leading sportsman to
have used platelet rich plasma
treatment and publicly acknowledged
its role in speeding a return from
injury.
Tennis player Rafael Nadal,
basketball player Kobe Bryant and
American footballer Troy Polamalu
are also on record as having
undergone this treatment.
However, some orthopaedic
specialists in North America are unpersuaded by the currently available
evidence on the efficacy of this form
of treatment.
Writing in the January 2014
edition of the Clinical Journal of Sports
Medicine [24 (1): 31-43], Andrew Dold
and colleagues from the University of
Toronto division of orthopaedic
surgery offer a critical review of the
technique in cartilage injuries.
“Currently, there is a paucity of
data supporting the use of PRP for
the management of focal traumatic
osteochondral defects. There is limited evidence suggesting short-
term clinical benefits with the use
of PRP for symptomatic
osteoarthritis of the knee, but the
studies published to date are of
poor quality and at high risk of bias.
“Further high quality
comparative studies with longer
follow-up are needed to ascertain
whether PRP is beneficial, either
alone or as an adjunct to surgical
procedures, in the management of
articular cartilage pathology,” he
said.
