Schmorl’s node is the prolapse of the intervertebral disc tissues into the body of the vertebra adjacent to it. It has a latent course, but can lead to the formation of an intervertebral disc herniation, compression fracture of the vertebra, spinal deformity. It is diagnosed according to the spine x-ray; in the presence of pain, an MRI is required. Treatment includes a calcium-rich diet, calcium supplements, therapeutic gymnastics, swimming, massage, and the exclusion of loads on the spine. Surgical interventions are not indicated and are carried out only with the development of complications.
ICD 10
M51.4 Schmorl’s [hernia] Nodes
General information
Schmorl’s node is named after the German physician Christian Schmorl, who described it in 1927. It is a partial prolapse of the intervertebral disc tissues into the bone structures of the body of a nearby vertebra. Unlike a true intervertebral hernia, it does not compress the spinal roots, vessels or the substance of the spinal cord. Schmorl’s node is most often diagnosed in children during the period of rapid growth of the bone system, when the rapidly growing bones of the vertebral bodies do not have time to acquire sufficient density and the more rapidly forming tissues of the intervertebral disc turn out to be denser, as a result of which they push the closure plate in the center of the vertebral surface adjacent to them. In most cases, the hernia has a subclinical course and is detected randomly by specialists in the field of orthopedics, vertebrology or neurology during radiography of the spine.
Causes
To provoke the formation of a Schmorl hernia can be any reason leading to a decrease in the density of bone tissue of the vertebrae. Most often, this is a disproportionate growth of cartilage and bone tissue, in which the latter lags behind in its development, and therefore areas of rarefaction and emptiness are formed in it. Of no small importance is the hereditary predisposition due to the structural features of the vertebral closure plates. Microfracture of the latter, leading to prolapse of the intervertebral disc tissues, can occur with spinal injuries, sudden lifting of an excessively heavy load.
Intensive loads on the spinal column and its repeated microtrauma during weightlifting, shaping, diving, during pregnancy contribute to the discharge of bone tissue. Osteoporosis of the vertebrae in old age is caused by age-related degenerative processes. With insufficient intake of calcium into the body as part of food, its increased excretion (for example, with hyperparathyroidism) or with a violation of its absorption due to intestinal diseases (chronic enteritis, enterocolitis), softening of the bone tissues of the vertebrae also occurs.
Osteoporosis of the vertebrae can be associated with a disorder of their metabolism with impaired blood supply. The latter may be due to Sheyerman-Mau disease, impaired posture, kyphosis, and other causes. Blood circulation in the tissues of the spine is closely related to the work of the back muscles. With a sedentary lifestyle, insufficient muscle activity causes a significant deterioration in blood circulation of the spine and can lead to dysmetabolism of its bone structures. Cosmonauts are the most illustrative example of such a mechanism for the formation of Schmorl node. In just a month of being in orbit, their bone tissues lose from 5 to 7% of their density.
Symptoms
Since there is no compression of the spinal roots and narrowing of the spinal canal, as well as due to the absence of inflammatory changes at the site of hernia formation, its course has a latent, hidden character. Multiple Schmorl node, which form on a certain part of the spine, can manifest clinically increased fatigue of the affected part of the spinal column. In some cases, there is a non-intense chronic pain that increases in the patient’s upright position and practically disappears in the supine position. Possible violation of posture.
Progressive Schmorl’s node negatively affects the functioning of the vertebral-motor segment and can lead to a number of serious consequences. The mobility and flexibility of the spine decreases. The increased load on the joints connecting the processes of the vertebrae contributes to the early development of spondyloarthrosis. Curvature of the spine may form: with multiple hernias of the thoracic region — kyphosis, lumbar region — lordosis. When jumping from a height or falling at the level of a vertebra weakened by a hernia, a compression fracture of the spine is possible. In addition, Schmorl’s node contributes to the formation of a true herniated intervertebral disc — the exit of disc tissues beyond the intervertebral space, which, in turn, entails compression of spinal roots, manifested by pain syndrome, the occurrence of sensory and motor disorders in the area of innervation of the compressed root.
Diagnostics
In diagnostics, the main importance is the meager nature of complaints or their absence, the presence in the anamnesis of indications of frequent microtraumation of the spine, cases of hernias in the patient’s relatives, curvature of the spine or posture disorders, determined by visual examination of the patient by an orthopedist, neurologist or vertebrologist. Radiography of the spine is a sufficient method of instrumental diagnostics. Often it is performed in connection with another pathology, and Schmorl’s node is an accidental diagnostic finding. Radiography can reveal curvature of the spine, the presence of osteoporosis, spondyloarthrosis, osteochondrosis of the spine.
The presence in the clinic of a pronounced pain syndrome, not typical for a Schmorl node, indicates the possible formation of a herniated disc. Since the latter is not visualized using radiography, in such cases, an MRI of the spine is indicated, and if it is impossible to carry it out, a CT of the spine.
Treatment
Due to the fact that initially harmless Schmorl node can have serious consequences, when they are detected, it is necessary to take measures to prevent progression. The main goal of therapy is to improve the metabolism of the bone tissues of the affected vertebrae and strengthen them. This can be achieved only by the complex application of measures simultaneously aimed at getting the necessary substances into the patient’s body, improving blood circulation and metabolic processes in the affected segments of the spine, removing excessive and uneven load on the spine.
Patients are shown a balanced calcium-rich diet. To increase the intake of calcium into the body, the use of cottage cheese, milk, and homemade cheese is recommended. In some cases, calcium pharmaceuticals and mineral metabolism regulators (calcitonin) are used. It should be borne in mind that an overdose of calcium negatively affects the functioning of the urinary system and may be accompanied by calcium deposition in the ligaments.
It is recommended to limit the load on the spine — to exclude equestrian sports, motorcycle riding, weight lifting, diving, aerobics and acrobatics. If you are overweight, you should reduce it, because it acts as a factor that increases the load on the spine. To improve blood circulation and strengthen the spine, you should do physical therapy, swimming. Massage, manual therapy, reflexology, underwater spinal traction are useful.
Surgical treatment is not indicated. The need for surgery may arise with the development of complications such as intervertebral hernia and compression fracture of the vertebra, if conservative treatment methods are ineffective.