Isthmic spondylolisthesis
Understanding spondylolisthesis
Spondylolisthesis is a Latin term for "slipped
vertebral body". For approximately 5%
of the population, a stress fracture occurs (usually
between the ages of five and seven) in the lowest
lumbar vertebral segment (L5). As a result, the
L5 vertebral body slips forward on the S1 (sacral
1) vertebral body. This process is almost never
due to trauma (see Figure
1).
The occurrence of spondylolisthesis often
results in no noticeable symptoms, and probably
80% of people never even know they have the
problem. In the 20% who do develop low back
pain, their pain is usually due to disc
degeneration in young adulthood.
Without the stabilizing effect of the bony
arch, the disc is forced to work harder to
resist shearforces (forward subluxation).
The disc is designed to function very effectively
in compression, but tends to break down when
shear forces are applied to it.
Pain from isthmic spondylolisthesis
Pain can also come from the fracture itself,
and the reparative tissue within may become
irritated and generate pain.
Although low back pain is usually the predominant
symptom of isthmic spondylolisthesis, some
patients experience leg pain due to nerve
pinching. The leg pain will generally be
worse when the patient stands or walks, and
it is almost always the L5 nerve that is
pinched.
Treatments for isthmic spondylolisthesis
For the most part, both the conservative and
surgical treatments for isthmic spondylolisthesis
are identical to both treatments for degenerative
disc disease.
By: Peter
F. Ullrich, Jr., MD
September 8, 1999
Updated February 28, 2001 |
