The primary pain source for lower back pain is damage to the spinal disc. The discs in our lower backs are highly susceptible to injury because when we reach puberty we no longer receive any kind of a blood supply to the disc. Because of this scenario, when our discs are subjected to stress and strain type of forces they begin to break down faster than they can repair.
Therefore, joints and discs heal very different and more slowly than most tissue in our bodies. Why?
Our spinal discs consist of 90-100 rings of fibrocartilage (annulus fibrosis) that kind of looks like an onion. In the middle of the rings is a jelly-like substance called the “nucleus pulposus” which is roughly 80% water. A healthy disc gets its nutrition and hydration through the nucleus by way of diffusion (not blood flow) from the surrounding bone.
This diffusion mechanism is performed in two ways: 1) Osmosis 2) Motion
Both methods that your disc uses to get nutrition (osmosis and motion) are reduced or eliminated by disc degeneration and herniation. In disc degeneration, the nucleus dries up (no water) and compresses. With no water, the nucleus cannot create enough osmotic force to diffuse the nutrients.
In disc herniation (tearing), the nucleus leaks into the surrounding annulus (often creating a bulge) and loses pressure and osmotic forces, thereby diminishing the nutrients to the disc. As you can see, once this process begins, it can quickly become a degenerative cycle, starving and dehydrating your disc. These injuries to the discs and joints may lead to pain, reduced motion, sciatica (pinched nerves), etc.
RATE OF BREAKDOWN VS. RATE OF REPAIR: This concept is key to understanding how we develop injuries to the tissues in our bodies. Let’s explore the bicep muscle for example. If one was to go to the gym and work out the bicep muscle everyday 7 days a week they would eventually injure the muscle tissue. After a workout our muscles need 48-72 hours in order to repair. Without the rest between workouts they will eventually fail and the muscle tissue will actually tear. It is no different for the discs in our lower backs. The more we strain the discs in our lower backs, the faster they will wear out and become injured, damaged tissue. Here’s a question:
Prolonged sitting is one of the most common ways for people to be on the wrong side of the rate of breakdown vs. rate of repair equation. Sitting and leaning forward increases the pressure bearing down on our lower back discs by 11 fold. Therefore, sitting at your desk 5 days a week 4-8 hours per day accelerates the rate at which your spinal discs breakdown or become injured. Other common ways to strain the discs in the lower back include: improper exercise technique, improper lifting, repetitive twisting movements and high impact activities.
It’s all about delivering nutrients and water to the disc. Because our discs do not receive any blood, it is imperative we take measures to deliver more nutrients and water to the discs in our lower backs. The most obvious place to start is to eliminate the variables that are causing the insult to the disc. For example, as mentioned above if you are used to sitting at your desk for hours on end, make sure you get up every 20-30 minutes-your back will love you for it. Cardiovascular exercise is also another major way to improve the delivery of nutrients and water to the discs. Cardiovascular exercise will actually help the discs receive the vital nutrients it needs to stay healthy.
The effects of gravity make the discs in our low backs highly susceptible to injury: When we lay on our backs with our knees up we are in the best position for the discs in our low backs. This position is good for our low backs because it is a non-weight bearing position and is not under the force of gravity. When we stand we increase the pressure in our discs 4 fold and when we sit and lean forward the pressure in our discs increases 11 fold!!! All of this pressure can add up over time and can lead to disc herniations causing low back and leg pain and debilitation.
The discs in your spine are very pain sensitive, some researchers assert they are the most pain sensitive structures in the lumbar spine. (17) The discs are a pad of thick collagen tissue called fibrocartilage between your vertebrae and contain a chemical called glycosaminoglycan which absorbs fluids to nine times its own volume. The inner most part of the disc is composed of 80% glycosaminoglycan and is normally 80% water filled. This high fluid content increases the pressure within the disc and acts to separate each bone in your spine. The disc acts as a shock absorber and pivot between each vertebral segment upon which they move. If it were not for the discs in your spine, the vertebrae would be one solid bone with no movement. The discs are the root cause of most lower back problems, therefore the health of the disc is vital to the well-being of the lower back.
Activities that create stress and strain to the lumbar disc include:
Far too often we have imbalances and weakness in the muscles that are made to stabilize our lumbar spines. The spine is a unique structure, in that, it must be a hard, rigid structure to protect the spinal cord and associated nerves while at the same time being flexible for proper trunk movement. This takes careful fine tuning from the brain and innermost (core) muscles in our lower backs that function to coordinate the movements in our spines. When we become deconditioned (from sitting too much) the body responds by basically getting lazy and recruiting only the “big” muscles that are easy to recruit.
Increase Nutrition to the Disc
SPINAL AND SPORTS CARE FOR THE ACTIVE INDIVIDUAL: (916) 933-9870