Herniated Disc - Pathogenesis and causes

Disc herniation.Herniation is considered to be caused by a defect in the fiber ring, most often by excessive stress applied to the discs. Posteriooara or injuries occur in the Posterolateral disc. Ring fiber morphology plays an important role in the propensity for a herniated disc in the rear. Histology shows that whatever its cause cracking, material always involves pulposus protrusion. Altered cartilage vertebral body and disc degeneration causes loss of nutrition. Trauma is the most common cause of ruptured nucleus pulposus. Result disc protrusion or extrusion of material in the spine. Predisposition to degeneration is also a factor.Herniated material may be contained in the fibrous or non-continuous ring.
Pathology of degenerative or traumatic.Biochemically, aging increases the rate of keratin sulfate to chondroitin sulfate, and modifying the proportion of condritin 4-sulfate and chondroitin 6-sulfate compared with concomitant loss of water. Decreases synthesis of proteoglycans, subtracting osmotic swelling and trafficking of oxygen and nutrients. Because stopping the intake of nutrients to the disc and protein metabolic products in stagnant noncolagene disk. Nonenzimatica glycosylation of these metabolites cause yellowing of the disc.
Anatomy of spinal vertebra and disc.Each disc is composed of two parts: the central nucleus pulposus and the fibrous ring. Each disc is attached to the upper and lower vertebrae cartilage, ligaments and anterior and posterior spine.The nucleus pulposus is composed of proteoglycans, particularly hyaluronic acid, moisturizing high hydrophilic core. Fibrous ring surrounding the nucleus and attaches to the adjacent vertebral bodies .. disc is fed by diffusion, has a low metabolic rate and is not supplied by blood or lymphatic vessels.Column stability is the result of three columns. Fracture or loss of stability of 2 columns determines instability. Anteruioara column consists of anterior and the posterior longitudinal ligament of the vertebral body. Average column consists of the posterior wall of vertebral body and posterior longitudinal ligament. Posterior column is formed by the vertebral arch.
Each vertebra has room to move, in the three translational axes and rotation around each axis. Not all vertebrae are similar, the cervical flexion had the greatest freedom, extension and lateral rotation. Thoracic vertebrae were flexion, extension, lateral flexion and rotation restricted but free because the ribs are attached, are small, their faces lined joints front and large spinous processes.Has a good lumbar spine flexion and extension with lateral flexion because discuirle are large, are directed to the posterior spinous processes and the girls are directed sagittal joint.
Predisposing factors of herniated disc.Factors favoring potential include: age, apoptosis, collagen abnormalities, decreased vascularitatii, added weights spine, abnormal proteoglicanii, obesity, sedentary lifestyle and lack of physical training.Radiculopathy or nerve root compression secondary inflammatory process affecting the nerve roots, neural. Symptoms are the result of a herniated disc through the ring hernierii its weak or cracking.When the spinal cord is damaged cervical or lumbar level appears myelopathy.