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Library: Article
Title: Sliding
Humeral Osteotomy (SHO)
Date: 7/1/10
Detail: New
Hope and New Treatment for Canine Elbow Dysplasia
Elbow dysplasia is a genetic disorder that occurs when
the bones of the elbow joint fail to develop properly, resulting
in misalignment, uneven joint surfaces and abnormal wear
within the joint along stress points. Within this condition,
a fragmented coronoid process (FCP) is the most common manifestation
of elbow dysplasia in dogs. With an FCP there is generally
a free osteochondral (bone chip) segment that has fragmented
or fractured off within the joint. As importantly, there
may be other elements of elbow dysplasia that affect the
elbow simultaneously, in various degrees of severity: full-thickness
cartilage erosion or cartilage loss (so called 'Medial Compartment
Disease'), Un-united Anconeal Process, Osteochondrosis dissecans
(OCD).
Diagnosis and Significance of Medial Compartment
Disease
With regular x-rays, diagnosis of FCP and Medial Compartment
Disease can be challenging, and frequently underestimates
the true severity of the condition in an individual patient.
Generally, we recommend a combination of physical examination
findings, x-rays, CT scans, and arthroscopy as a means of
most completely and accurately assessing (staging) the condition
of an elbow with elbow dysplasia.
Depending on the severity of the condition, dogs with Medial
Compartment Disease generally require more or less continuous
use of anti-inflammatories, stem cell therapy, pain-relievers
and acupuncture to preserve quality of life. Considering
the risks and costs of long term medications and the diminishing
response to therapy as the arthritis builds, a good option
for pet owners to consider is advanced surgical intervention.
Advanced surgical procedures include arthroscopy, elbow
replacement and Sliding Humeral Osteotomy with or without
the addition of Stem-Cell Therapy.
Total Elbow Replacement
Total elbow replacement may be indicated when cartilage
damage has spread completely throughout the joint and is
no longer limited to the medial compartment. There are a
variety of commercially available elbow replacements that
have been tried over the past two decades none of which has
been shown to be safe, reliable and effective enough for
recommended use at this time. Research in this field is very
active and there is promise on the horizon for a more reliable
unit.
Sliding Humeral Osteotomy (SHO)
The Sliding Humeral Osteotomy (SHO) was experimentally
derived in the Orthopedic Research Laboratory of the University
of California, Davis in the late 1990's. This research generated
a number of clinical procedures which have since been refined
into what we know today as the SHO. The rationale of the
SHO is based on an essentially similar procedure performed
in the human knee. The SHO realigns the limb such that there
is a shift of forces from the diseased medial compartment
over to the healthier lateral compartment. This realignment
relieves the pain of bone-on-bone contact and allows the
damaged joint an opportunity to heal.
SHO - The Procedure
First, we will perform elbow arthroscopy to better assess
and characterize the cartilage quality. At this time we traditionally 'instrument' the
joint to capture and remove the floating FCP segment.
After the joint is treated a medial approach is made to
the humerus. An osteotomy is made in the middle of the humerus
and a bone plate with a 'step' and screws is applied such
that as the screws tighten the two individual pieces of the
humerus slide past one another resulting in an eccentrically
loaded bone.
Clinical Experiences
Over the past 3-4 years the SHO procedure has been performed
in well over 100 dogs. Careful clinical studies have been
performed)to evaluate the efficacy of this procedure. The
majority of dogs undergoing SHO have decreased lameness by
3 months post-operatively with many of the dogs exhibiting
complete clinical soundness at 6 month post-operative. In
nearly all patient cases, there was profound owner satisfaction
with the outcome. This contrasts steeply with results obtained
from medical management only with or without FCP removal.
SHO Surgeons
There are fewer than 50 trained veterinary surgeons currently
certified for performing the SHO. Each surgeon has been hand-selected
and invited to this new and innovative technological training
seminar, and each is highly experienced in orthopedic veterinary
surgery. VSCD surgeons, Dr. John Haburjak and Dr. Kim Carlson,
are SHO-certified and we are pleased to offer this procedure
as well as other diagnostic and treatment options for canine
elbow dysplasia.
Fitzpatrick N, Yeadon R, et. al. Techniques of Application
and Initial Clinical Experience with Sliding Humeral Osteotomy
for Treatment of Medial Compartment Disease of the Canine
Elbow. Vet Surg 38:261-278, 2009
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