When sciatica is not sciatica...
Low back pain is a very common condition. It sometimes
spreads to the leg, and is generally known as "sciatica". Originally
the term was meant to indicate that there was pressure on the sciatic nerve,
and symptoms; mainly pain, tingling and weakness, were present in the regions
supplied by the sciatic nerve.
The most common cause of sciatica was/is; compression from
a herniated disc, most commonly the L5/S1 disc.
The good news with the diagnosis of sciatica is that most patients
get better within three months, and no surgery is required. One year later it
makes no difference whether you had surgery for the disc hernia or not. The
initial swelling from inflamed disc tissue settles over the weeks, and therefore
the compression on the nerve eases, and with it the symptoms.
Many people believe they have sciatica when they experience symptoms of back pain and leg
pain (namely pain in the buttock and back of the thigh). In the majority of cases, the symptoms are not due to pressure on the sciatic nerve, but from other
conditions, like hamstring problems, and the sacro-iliac joint that does not function as
What is the sacro-iliac joint?
The sacrum (tail bone) and the two hip bones (iliac or
innominate bone) from the pelvis, and the two sacroiliac joints are located at the
bottom of either side of the spine, above the buttocks.
Their function is to protect the pelvic organs. In addition,
the transfer load (weight) from the trunk to the legs and vice versa. For this
they need to stiffen up. But they also need a minimum of movement to absorb
torsion, for instance when we walk. Otherwise we would walk like A2D2, the Star
Wars companion to Luke Skywalker.
strategies to adapt to the different situations. It is achieved in
several ways. The surfaces of the joints match each other, there are strong
ligaments between the two bones, and several muscles contract to provide
stiffness; these are the deep muscles of the "core". The integrity of
the ligaments and the timing of the muscles activity combine to provide the required
amount of pressure across the joint to fulfil its functions. If any of them
fails, over time other muscles take over, the joint locks in the wrong
direction and the result is lower back
pain, that spreads to the buttock and the thigh (back and side).
The usual cause of these symptoms can be a fall, or a series
of falls on the buttocks, as well as repeated jumps, landings, repetitive
lifting and car accidents. Rear end collisions with one's car stationary (at a
traffic light, for instance) are typical. It can take months, even years to
develop symptoms, because we have many mechanisms to compensate. When we
"run out of compensation" symptoms appear.
The diagnosis; we call it sacro-iliac joint incompetence-is
made by history, clinical examination, and more recently with a new imaging
technique, called SPECT-CT, a combination of low dose limited CT and a bone
scan. While it involves a small amount of radiation, it is the only imaging
technique that will identify problems in the biomechanics of the pelvis, and
the overuse of the alternative compensation t=strategies (hamstring, adductor
and gluteal tendon changes).
Treatment is usually with a very targeted exercise programme
to improve timing and endurance of the
"right" muscles. It begins with very simple, "nothing to
it", exercises to activate the deep core muscles and develop endurance,
before it builds up with other muscles and activities.
In a personal series of more than 1200 patients, 75% to 80%
improved with these exercises, under the direction of an experienced
physiotherapist. The rest may require proliferative injections into the deep
ligaments of the joint. Very rarely (less that 1%) surgery is required to fuse
In summary, not every "sciatica" is real sciatica.
Sacro-iliac joint problems are more common than originally thought (up to
20-25% of cases of low back pain), but most of them respond to specific