There are several types of joint conditions which may affect the stability of the back or cause an instability of the musculoskeletal system which affects the curvature of the spine. In some types of joint conditions, wear and tear causes a breakdown of the joint tissue separating articulating bones, resulting in the friction of one bone against another. In other cases, the joints may wear out earlier in a person's life as some infection or other disease process causes our body's own immune system to attach our synovial joints. In other cases, the joint tissues may become damaged due to injuries and other types of trauma. Many different types of joint conditions affect the health of our backs directly, or they may cause indirect problems for our backs as they change our posture and body mechanics. Body mechanics is the study of how the movements of our bodies affect the structures of the musculoskeletal system. As our joints age and become injured, we may change the way we hold our bodies as we move, or begin to favor one side of our body over another. The health of the spine depends on us using our backs and limbs in ways that don't put unnecessary pressures on the discs, ligaments, and muscles of our backs. As we overload the back muscles or stretch the spinal ligaments, we may experience pain related these structures being overstretched or overexerted. As a result of this sprain and strain of the soft tissues, we may experience acute or chronic back pain. Let's look as some of the joint conditions which may affect our backs or our lifestyle.
Sacroiliac Joint Dysfunction: At the base of our spine, the top of the sacrum is connected to the last lumbar vertebra at the L5-S1 intervertebral disc. The sacrum itself is anchored to the ilium on both of its lateral borders by a pair of sacroiliac (SI) joints. These SI joints allow for enough movement to provide additional cushioning of the spine as the pressures of gravity press down on the lower spine. These joints are also rigid enough to hold the base of the spine in position, so that it is relatively stable in its position in the body. Sacroiliac joint pain may occur when there is either too much or too little movements in these joints. If these joints are two rigid and inflexible, the sacroiliac joints dysfunction may be described as fixation or hypomobility. If there is too much movement in one or more of the SI joints, the condition may be classified as instability or hypermobility. Let's take a look at how the two types of SI conditions affect the body, in terms of symptoms.
Fixation or Hypomobility: Fixation describes when there is too little movement of the SI joints in responses to changes in patient positions, activities, and gravitational loads on the spine. Fixation SI joint pain is experienced in the lower back or buttocks. The patient's pain may begin in the lower back or buttocks and radiate down the leg. This radiating pain typically stops at the knee, but has been reported radiate as far as the foot on some occasions. The symptoms of this condition resemble the symptoms of sciatica, which also involves radiating pain down the leg as a result of compression of the sciatic nerve.
Instability or Hypermobility: This pain is usually felt in the lower back and/or hip area. The pain may radiate to the groin area.
Sacroiliitis: Sacroiliitis describes the inflammation of the sacroiliac joint. This joint usually becomes inflamed by inflammatory conditions such as spondyloarthropathies, which involves a class of inflammatory forms of arthritis linked to the HLA-B27 antigen. Spondyloarthropathies such as ankylosing spondylitis, reactive arthritis, and psoriatic arthritis all have a positive correlation to the HLA-B27 antigen. This means that the majority of people with one of these inflammatory diseases test positive for the HLA-B27 antigen. These inflammatory diseases cause pain related to the inflammation of the spinal joints they affect, and stiffness related to the fusion of the bones that these joints were designed to separate and protect.
This condition is different from Sacroiliac joint dysfunction in that is specifically focuses on the inflammation of the joints. The mobility of these SI joints may not be affected by the medical condition which causes it to become inflamed.
Causes of Sacroiliitis may include endocarditis, IV drug use, IV drug addiction, osteomyelitis, pregnancy/childbirth, lupus, and rheumatologic disease.
Facet Joint Problems: Though many people assume that the cause of their lower back pain is due to a "slipped disc", instability and inflammation in the facet joints are also involved in a significant amount of cases. Many people who experience back pain assume that their symptoms are related to the discs of their lumbar spine, especially after seeing their MRI and X-Ray reports describing disc degeneration in their spine. But facet joint problems may be the actual cause of low back pain even in cases where imaging tests indicate spinal disc herniations. Facet joint pain may be treated by physical therapy, steroid injections into the facet joints, or spinal fusion surgery designed to prevent unstable motion at the affected facet joints.