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"70% of the population
will suffer from low back pain at some time in their life".
Back and neck pains can be caused suddenly by a specific
injury such as lifting a load awkwardly or it may come
on gradually. This is normally due to an accumulation of
several minor factors. This could include poor sitting
posture at a computer or driving, poor physical fitness
and having weak muscles that support the spine. If you
leave your problem untreated these muscles will become
even weaker and the spine becomes more stiff and
painful. The problem then will become chronic and
recurrent. Therefore it is important to get your spine
checked over as soon as possible, even if you have a
minor twinge, if you want to prevent long-term problems.
A lot of people avoid early treatment as their problems
are intermittent but research shows that early
intervention is the most successful way to resolve back
and neck pains.
Back anatomy
The back is made up
of 24 building blocks called vertebrae which
support the body. There are seven cervical
vertebrae, twelve thoracic vertebrae, and
five lumber vertebrae. The majority of the
problems stem from the lower lumber
vertebrae where we see most of our problems.
The vertebrae sit on top of each other
separated by the spinal disc. On the back of
each vertebrae there are two joints on each
side called facet joints. Half the weight of
the body goes through the body of the
vertebrae and the disc while the other half
of the bodies weight goes through the two
facet joints.
The spine has three
healthy natural curves. This allows the
spine to acts as a shock absorber. As a load
is placed upon the spine the curves bend to
dissipate the force. If for any reason these
curves are lost then there is a dramatic
increase of force through the individual
vertebrae and disc.
The facet joints are
true joints very similar to the joints in
your fingers. They allow the back to bend
forward and backward as well as rotate from
side to side. They are placed under the most
stress when the back is bent backward
especially with some rotation. Like any
joint it is easily sprained and because
there is so much stress through these small
joints they are more prone to degenerate.
The most talked about
structure in the back is the spinal discs.
These shock absorbing disc sit between each
vertebrae. They are made up of a softer
centre and a realatively hard outer shell.
They also provide a lot of stability to the
lumber spine. Problems usually start when
the outer annulus breaks down from injury
and aging.
The muscles and
ligaments around the spine are crucially
important. There is a long ligament that
runs down both the front and back of the
spine. They stabilize the spine and like any
ligament around any joint in the body they
can be sprained and cause problems short and
long term. The back muscles are important to
support the spine and the abdominal muscles
are also connected to the lumbar back tissue
and have a very important role in the health
of your back. It is these muscles and
ligaments which we can have the most effect
on to ensure a healthy back.
The messages from the
brain to the body are carried in the spinal
cord. The spinal cord runs down through and
is protected by the vertebrae. At each
vertebrae there exits a spinal nerve. Often
the spinal nerve is injured or irritated as
it leaves the vertebrae. The spine is a very
complex structure which can easily have
problems. Now we know the anatomy we will
discuss what can go wrong in the next
column.
The back is a
very complex structure, many structures within the
back can be causing pain.While
we can often be very specific about what exactly is causing your
back discomfort, more often than not we can not. After taking a
careful history of your problem and a thorough examination we
usually have a good idea about your back problem but NOT a
definitive diagnosis
Back pain can be causing symptoms locally in the back and buttock
region or it can cause referred symptoms into the leg and as far as
the foot. It can be a dull vague feeling or a very direct shooting
pain down the leg. Other complaints include pins and needles,
numbness, muscle weakness and general stiffness. Abnormalities of joints, muscles and neural structures may
contribute significantly to back pain.
Recent onset of back pain is
usually from the joints. In long standing cases of low back pain
there maybe associated muscle and neural involvement. Chronic low
back pain is caused by instability in which there is disc
degeneration. This can cause inflammation of the joints. An
imbalance of muscles is also usually present showing weakness of the
main stabilisers transverse abdominus and multifidius. Poor posture/postural control can result in this muscle imbalance. Muscle strains are rare in the back unless taking part in extreme
torsional sports like javelin or bowling in cricket where stress is
placed on the quadratus lumborum.
MECHANICAL BACK
PAIN Most back pain falls into this category. The pain is vague and
not specific to any structure. It is usually do to a dysfunction of
the supporting ligaments and muscles. The stress to the back
structures causes the pain. The predisposing factors for this pain
vary with the age group. As adolescents grow the bones grow faster
than the muscles and ligaments. This leads to tightness and weakness
of the structures supporting the back. With increased activity such
as athletic participation there is increased stress on the back
structures and pain ensues. As we get older a different process
takes over. The back naturally starts to degenerate after about age
20. If we do not keep the back in shape the muscles get tight and
put stress on the back structures. Combine this with the weakness of
the muscles supporting the spine and we have a situation where there
is either an increase in abnormal movement between the vertebrae or
a decrease in the normal functional movement between the vertebrae.
Often these two occur at the same time in different parts of the
spine.
Techniques have demonstrated that damage to the facet joints
and intervertabral disks are the most common causes of pain in the
back.
Intervertabral disc/facet joint injuries
Previously only two types of disk injuries were recognised. One
was a prolapsed disc or rupture (usually causes a sharp lacerating pain
into the foot). The second was degeneration, a narrowing of the disk
space (Spinal Stenosis). However the outer third of the disk (anulus
fibrosus) is quite sensitive and can be a source of pain without
rupture or degeneration.
Excessive rotational or compression forces can lead to these
injuries (bending forward and twisting as in lifting).
Differences of pain provoking techniques can help to
differentiate between the disc and joint (flexion with disc
injuries, extension with joint injuries). Disc injuries usually
present as central back pain and unilaterally with joint injuries.
However these are used as guides as they can coexist together.
Symptoms of Disc injuries
- Some disruption of the lumbar disc or tissue that supports the
area of the disc will cause pain that is confined to the lower back,
it is usually on one side more than the other.
- It may refer into the
buttock and lateral hip but no further. It is an aching type of pain
with the occasional sharp twinge.
- If the disc has protruded you may experience a more predominate
leg pain. This will follow the pattern of a particular nerve root.
- Flexion is usually the movement affected. Sitting may be
uncomfortable. If a large herniation is present a lateral shift will
be present (protective scoliosis). Side flexion may cause symptoms
but rotation should be pain free but can cause a pulling sensation.
Facet joint injuries -
view video about facet joint
What are the Facet (zygapophysial)
Joints?
The facet joints are synovial joints which help support the
weight and control movement between individual vertebrae of the
spine.
The facet joints work together alongside the intervertabral discs
to form a functional working unit. The facet joints direct the plane
of motion at each vertebral segment which is dependant on their
angle and orientation.
Throughout the spine the angles and orientations differ which alters
the possible movement allowed in that area. The facets have an
articular cartilage and articular capsule which allow movement but
provide stability. Facet joints have a nerve supply from two levels,
one branch arises from the nerve root at that level and the second
from the level above. When functioning correctly, facet joints move
freely controlling the movement of the spine.
Facet joint pain may arise directly from the facet joint either
from inflammation or nerve impingement
What are the symptoms?
-
Common symptoms associated with this
condition are adjacent muscle spasms which can pull the patient
out of alignment, leading to a guarded posture.
-
Often patients will report “I just bent over
to tie my shoe laces and my back went and I couldn't move”. The
usual acute attack of back pain involving facet joints occurs
suddenly with no warning. It can appear dramatic and patients
are in much discomfort and cannot move very well.
This spasm of adjacent muscles is the bodies way of protecting
the area and tries to prevent you from moving and incurring more
damage. Symptoms can vary greatly and be confused with disc related
disorders as its possible for patients to report referred pain into
the lower extremities. The traditional facet locking syndrome may
lead to such an acute attack but can be resolved successfully by
freeing the offending joint and restoring normal function. This
should only be attempted by suitably qualified practitioners
following the correct diagnosis.
- It can be felt locally to the central lumbar region with some pain
radiating across the back as it progresses. It can become more
noticeable on one side and can be felt in the buttock region.
- If more pressure has been applied to the posterior structures the
area of symptoms may travel as far as the posterior knee. Walking
can be painful and relieved with sitting. But if sitting is held it
can cause stiffness.
- It mainly effects extension movements, side flexions to one side
may be limited especially towards the side that has pain. Rotations
may cause stiffness at the end ranges but should be full range and
pain free.
- This condition is most present in those who have an increased
lordosis curve with increased muscle tension in that area.
If you have sustained a strain to the joint, both flexion and
extension will be limited with limited side flexion to the affected
side and rotation may cause a pulling sensation. Muscle spasm will
be present. It can cause a flattening of the lumbar curve. Pain will
be felt in the back and will radiate to one side across the iliac
crest.
Back pain is more prevalent than the referred symptoms for
intervertabral/facet joint injuries. If prolapse has occurred than
the radiating leg pain is greater than the back pain (Sciatica).
Other symptoms of disc prolapse are muscle weakness, sensory changes (pins and
needles, numbness) and diminished reflexes in the lower extremity.
If you suffer from all of these and also start to have abnormal
bladder function you need to have immediate referral to your gp.
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