Between each vertebra in the spine there are soft tissue "discs" that help cushion the spine and add mobility to what would otherwise be a rigid structure. The problem starts when a disc becomes injured or damaged in someway. This can lead to disc degeneration, a disc protrusion, and even disc ruptures. All of these separate injuries can result in similar types of back pain and are often difficult differentiate with out the use of special imaging studies like X-rays or MRIs.
Disc injuries come in many different the two most common of which are disc herniations and degenerative discs.
How a Disc Problem Starts.
A disc is a roundish structure that is soft and pliable. In some respects is built like a jelly donut. In the center of the disc a viscous material that can be described as a cross between the consistency of "crabmeat or thick jelly" The circumference of the disc is a firmer almost rubbery like material that keeps the center or "nucleus" in place while also provides some resiliency to the disc. All in all, the disc with it high water content jelly like center and firmer outside, operates like a cushion between the bones of the spine.
When we move the spine, our discs bend and deform allowing what would be otherwise be a rigid column, to flex in 6 separate directions.
The problems start when the disc becomes injured somehow. This usually occurs in the way of small fissures or cracks that begin to develop near the center of the disc. When these interior cracks and fissures begin to aggregate, the jelly like material which is normally held inside the center of the disc can begin to move toward the edges of the disc. Because the rubber outer portions of the disc are a little thicker and stronger the jelly stays contained but begins to push outward creating either a bulge or a "protrusion".
In severe cases the pressure on the outside of the disc gets so severe that the jelly can actually break through creating a "rupture". This is the worst form of disc herniation since it will often require surgical intervention to remove the extruded disc material.
Nerve Pressure or the Infamous "Pinched Nerve"
All this would be painless except for the fact that located millimeters from the outside edge of the disc are some very sensitive spinal nerves. When the disc bulges it pushes outward and touches these nerves spinal nerves creating pain. Because the nerves have little ability to move away from the encroaching disc, the nerves become compressed ("pinched") and the result is pain.
Why Does the Pain Traveling from the Back to the Leg?
Some of this nerve is quite long and the pressure caused from the disc can be projected down the course of the long wire like nerve to distant locations. In mild pressure the pain may be localized to the back or buttock but in moderate to severe pressure the pain can project to the lower leg, as far down as the foot and ankle. To make things even more complicated, some nerves conduct different sensations such as burning, aching or even numbness, rather than sharp pain. Regardless though of whether its burning, numbness, tingling or sharp pain, the cause is the same...pressure on the nerves in the spine by a damaged and deformed disc.
The other kind of disc problem... Disc Degeneration
Degenerative discs are a little different. They may start the same way with small crack and fissures inside the disc but in stead of the interior disc material migrating toward the edge of the disc causing a bulge or protrusion, the center of the disc begins to dry out and loose its water content beginning, a gradual process dehydration. The interior water content of the disc can lessen to the point that the disc begins to "deflate". When the disc begins to loose its internal pressure, it begins to thin under the weight of the body and gravity. This disc thinning can become so severe that not much of the original disc height remains. This is a problem since the disc and its height is what keep our vertebrae apart from one another, giving fragile nerves room to exist the spine. If the disc thins too much our vertebrae gets so close that they can rub against one another creating a whole host of other problems.
Muscular Back Pain, Why, "Taking two Aspirin and Call Me in the Morning" is a Bad Idea.
Muscular back pain is something that most people have experienced at one time or another during their lifetime. Lifting the wrong way, getting out of bed after sleeping the wrong way or any number of the activities of daily life all have the potential for creating muscle pain. Muscle pain is most often characterized by a dull achy pain, limited the region of the muscle under distress. It is often localized to a small region and is irritated by using that muscle, while relieved by rest.
Our office treats muscle pain both directly by addressing the soreness or pain, but also by trying to "fix" the reason for injury. Often people do things during their activities of daily life that create undue stress on certain muscles and the pain that results is nothing more than a "fire alarm" telling us that something is wrong. This might mean sitting the wrong way at work or using the phone against our shoulders all day or even working out the wrong way at the gym. In any case, the real art to treating muscular back pain is to not just relieving the pain, which is often rather simple, but also figuring out why someone hurt the muscle in the first place. To do this we take a biomechanical approach to many of these complaints. We will often look at posture and even photos of the work place to try delineate the sources of daily physical stress that could be the root for the recurring problem. If the muscle pain was due to a single event like a strain, we try and teach our patients techniques to improve the strength of that muscle, thereby reducing the likelihood of future injuries.
The long and short of it is that we look as muscle pain differently than most offices. We don't just prescribe muscle relaxants or pain killers to suppress the pain, we try and get to the cause of the problem and develop a plan to fix it. If you don't take that kind of proactive approach, people tend to re-injure themselves or regress to the point where muscles become chronically injured and much harder to treat.
Sacroiliac Joint Pain. The "missing link"
There is a joint in the lower back/buttock region that is often overlook in the treatment of back pain. It is called the sacroiliac joint, or SIJ for short. It is an important weight bearing joint that connects the bottom of the spinal column (the sacrum) to the bones of the pelvis (iliac bones). This joint is often a source of pain because of the number of things that we do during our day that can put it under stress. Even simple things like excessive sitting have a tendency of irritating the SIJ which in turn can produce severe back pan, buttock pan and even radiating leg pain to the knee.
The difficult part is identifying the fact that the SIJ is the culprit in cases of back pain. The joint itself, even if very injured, many times looks normal on plan X-rays and MRI's. Misdiagnosing this potential source of pain can be devastating. Many people suffer from extreme and disabling back pain from SIJ dysfunction, and go years before receiving the right diagnosis. The unfortunate part of this scenario is that most forms of SIJ pain are very simple to treat when caught early. The SIJ responds well to simple treatment programs like joint manipulation, and localized treatment like ultrasound or anti-inflammatory medication.
Because of the sheer number of back pain cases that we see in our clinic we very experienced in both identifying and treating this less common source of back pain. Many of our patients with SIJ pain get out of pain in a short period of time and return to full function even after what, is often years of intermittent pain.
The spine itself is nothing more than a series of hollow vertebrae stacked one on top of each other. The result is that the spine acts like a long flexible tube made up of many segments. Through this tube passes the spinal cord which is a cable like structure of many parallel nerves. As the spinal cord travels through the spinal column, there needs to be enough room in this canal for the bulky nerves to travel un-pressured. In spinal stenosis the spinal canal becomes narrow because of age or denegation and the space that the nerves occupy become compromised. The result is that spinal nerves come under pressure, which in turn can lead to pain or numbness in the area that those nerves eventually travel to.
When you compress a nerve you will often feel pain near the site of compression (the low back in this case) and many times you will also get pain that projects to wherever that nerve is heading. The fact is that nerve act very much like electric wires. They are quite long and are design to conduct electric like signals to remote locations. When you press on the mid section of a nerve, as in spinal stenosis, the nerve will send signals down its length creating the sensation of pain at the ends of the nerve, which for the spinal nerves is most often in the leg. The result is that stenosis will often lead to lower back pain but also numbness, and achy pain in the lower legs including the calf ankle and many times feet.