Spondylolisthesis
Spondylolysis is the one of the most common causes
of low back pain in teenagers. It is basically a fracture in
one of the vertebra of the lower back, most often in
the 5th vertebra.
Clinically spondylolysis is defined as a defect in
the pars interarticularis of a vertebra, the area between two
joints, caused by repeated microtrauma, resulting in
a stress fracture. When the fracture is present it allows the
vertebra above to slip forward on the vertebra
below. This results in a condition called spondylolisthesis.
Approximately 3-7% of the general population have
spondylolysis. In certain athletes, the incidence increases to
22% in weight lifting, 29% in wrestling and 43% in
diving. Over 25% of the Olympic Romanian gymnastics
team during the years 1970-1990, among them Nadia
Comaneci had problems involved with spondylolysis.
Patients with suspected spondylolysis should be
evaluated initially with plain radiography. On lateral
radiographs, the most sensitive projection,
spondylolysis appears as a linear lucency in the pars interarticularis.,
This lucensy also can be seen in oblique radiographs
and has been termed the “collar on the neck of the Scottie
dog”.
Further imaging may be warranted, MRI, CT and SPECT
bone scintigraphy are used to further evaluate these
patients. MRI of the lumbar spine is very sensitive
for detecting early acute stress reactions in the pars
interarticularis where there is only marrow edema
and microtrabecular fracture. These findings are not visible on
CT.
People with spondylolysis/spondylolisthesis may feel
pain and stiffness in the centre of the low back. Bending
fully backward increases pain. Doctors refer to this
type of back pain as “mechanical back pain” because it most
likely comes from excess movements between the
vertebra. The younger child has a higher chance of further slip
with growth. Girls are more prone to progressive
slip than boys. Grade I indicates 25% slip, Grade II up to 50%,
Grade III up to 75% slip and so forth. The higher
grade of slip, the more serious the problem, and the higher the
chances of further slip. For grades I and II,
conservative treatment is usually instituted.
This will be similar to treatment for spondylolysis,
with the use of a rigid brace and physical therapy. X-rays are
done every 3 to 6 months to check the severity of
the slip. Keeping the spine from moving can help ease the pain
and inflammation. It can also improve the chances
the bone will grow back together. There might be a need to
take some time away from sports activities,
especially if it requires repeated back bending. If the pain does not
improve, or there are neurologic symptoms down into
the legs and /or follow up X-rays demonstrate further slip,
surgery may be needed.
Surgery consists of decompression of the nerves and
fusion of the vertebra to prevent further slipping and to
relieve pain. In young persons the fusion rate is
over 90% and the success-rate generally high. A similar illness
in adults is called degenerative spondylolisthesis.
It is difficult to detect in its initial phase which might cause
confusion and delayed treatment. We will discuss
that in next months issue.