Tuberculous spondylitis is the most severe and common form of osteoarticular tuberculosis. In most cases, tuberculosis decay affects the thoracic spine (about 60% of cases), the second place in frequency is the lumbar (about 25% of cases), and the third is the cervical and sacral parts. More often, caries damages the vertebral body; primary damage to the arches and processes is rare.
The softness of the spongy substance, the insufficient differentiation of the cortical layer in childhood favors the rapid development of inflammatory phenomena in the central parts of the vertebral bodies, which is accompanied by the destruction of the vertebra and neighboring intervertebral discs, the transition of the process to neighboring vertebrae, deformation of the spine and the formation of a hump ( gibbus ). The earlier the disease manifests, the more noticeable is the subsequent spinal deformities caused by it. In adults, due to the density and thickness of the cortical layer, a denser spongy substance and the development of locking plates of the discs, the spread of bone caries occurs much more slowly and over a more limited extent; often only two adjacent vertebrae are affected and a pronounced spinal deformity does not occur.
Compression of the spinal cord can be caused by the remnants of the destroyed vertebral bodies that are moved posteriorly by type of sequestration. Crucial importance in spinal cord compression syndrome is given to subligamentary or epidural abscess or granuloma. The severity of neurological disorders is very different – from radicular symptoms to complete paralysis with sensitive disorders and impaired pelvic function. The so-called early paralysis develops at the height of the inflammatory process in the first 2-3 years of the disease. As a rule, they are caused by a paravertebral abscess communicating with the spinal canal, exfoliating the posterior longitudinal ligament of the spine and sometimes penetrating into the epidural space, which causes blood and lymphostasis , edema and compression of the spinal cord. With the timely elimination of acute inflammatory phenomena in the cavity of the spinal canal, a favorable outcome of the disease with regression of the spinal lesion is possible.
Late paralysis occurs a few years after the onset of the disease, during a period of seemingly silent process. The reasons for them are: 1) exacerbation of tuberculosis infection in torpid leaking foci in the vertebral bodies and in calcified abscesses; 2) changes in the anatomical ratios of the vertebral bodies, deformation of the spine in the form of an acute-angled hump, displacement of the vertebral bodies posteriorly or sideways, a sharp narrowing of the spinal canal; 3) degenerative changes in the substance of the spinal cord. If late paraplegia is a consequence of an exacerbation of torpid flowing spondylitis, then it does not significantly differ from early paraplegia, and in the genesis of compression syndrome then paravertebral abscess plays a leading role . Late paralysis is less predictive and most often leads to irreversible consequences. Tuberculous caries of the two upper cervical vertebrae has its own characteristics in connection with the development of the process in the area of the occipital-vertebral joint and the proximity of the medulla oblongata. The defeat of one of the joints of the occipital-atlanto- epistrophaeal complex is manifested by pain during head movement, leading to the development of reflex spasm of the cervical muscles. When the front arm of Atlas is destroyed, the head settles, the neck becomes shorter. Due to increasing pain, patients are forced to constantly support the head with their hands, which is typical for lesions of the upper cervical vertebrae. Compression of the trunk and the upper cervical spinal cord may be due to the tooth-like process, which, when the head settles, penetrates upward into the large occipital foramen and comes into contact with the medulla oblongata.
When the head “slips” forward with a dislocation of the vertebra, compression occurs between the tooth-like process and the posterior arch of the atlas. With acute displacement, sudden death can occur. In the clinical picture of neurological complications of thoracic spondylitis, radicular pains of the type of intercostal neuralgia and spastic paraparesis of the lower extremities with conduction disturbances of sensitivity and disorder of the pelvic functions come to the fore . The defeat of the thoracolumbar region can be manifested by the development of spastic- atrophic or flaccid paralysis of the legs, sensory disturbances, severe pelvic disturbances and radicular pain in the lower back and legs. For lumbar spondylitis, the occurrence of radicular pain is most characteristic. The leading role is played by bone compression of roots at this level and often subligamentary and epidural abscesses.
Treatment of tuberculous spondylitis
Until the 50s of the current century, a conservative method of treating tuberculous spondylitis was widespread, including a long stay in a plaster bed and a spa complex. In the 1950s, there was a departure from the traditional tactics of conservative sanatorium-orthopedic and anti-inflammatory treatment, and indications for direct surgical intervention in the bone cavity became wider. This was facilitated by the fact that the use of anti-TB drugs (streptomycin, phthivazide , PASK, etc.) improved the results of conservative treatment, but, as a rule, did not cure vertebral caries. This partially found its explanation in the formation of a tissue barrier that prevents the rather intensive penetration of these drugs into the cavity of bone caries. Therefore, there was a need to open the bone cavity and cold abscesses, remove their contents and curettage of the wall of the bone cavity, which was supposed to open access to medicinal products directly to tuberculous foci, to improve blood circulation in the affected vertebrae and regenerative processes in the vertebrae themselves. In the case of compression of the spinal cord and its roots, radical surgery should simultaneously eliminate all compression factors.
With mild degrees of early paraparesis , sanatorium-orthopedic and anti-inflammatory treatment is initially shown, and only with its inefficiency do indications for surgical intervention arise.
The use of surgical methods for treating tuberculous spondylitis and their complications in combination with conservative ones has led to a significant reduction in overall mortality compared to using only conservative methods of treatment, as well as to improving treatment outcomes. In general, the prognosis for both life and functions during treatment is better in children than in adults, and the modern and possibly earlier prescription of anti-TB drugs in combination (if indicated) with orthopedic measures (primarily using an immobilizing bed ) plays a significant role ) or with surgery.