Abstract
Introduction
The rigid angular kyphoses in the young patients with spinal TB are not only a cosmetic problem, they also lead to cardiovascular, respiratory, and neurological disorders. The correction of the deformity could be reached by combination of the debridement, anterior column reconstruction, the shortening of posterior spine, and extended posterior instrumentation. The zone of instrumentation needs to be longer than the anterior fusion for significant correction and spinal stability.
Materials and Methods
Total 13 children from 2.5 to 12 years with TB spondylitis of the thoracic and lumbar spine complicated by severe angular kyphosis underwent 1-day combined surgery included anterior debridement followed by cortical bone allografting and posterior osteotomy with correction and instrumentation by laminar or hybrid devises. The anterior reconstruction exceeded three segments in all cases (maximum-replacement of 10 vertebral bodies).
For real deformity correction the posterior instrumented zone exceeded the length of anterior reconstruction up to 1 or 3 segments cephalad and caudad. The operations were performed under the SSEP monitoring and additionally with wake-up test-in older cases. Neither neurological nor inflammatory complications were in these patients. The normal or closed to the normal sagittal profile was reached in all cases.
Follow-up period ranged from 2 till 13 years. Complete follow-up: 13 cases. All patients have annual X-ray control. There wasn't any signs of anterior pseudo-arthrosis revealed.
The condition of subchondral vertebral plates and the height of intact intervertebral disks within the zone of instrumentation and disks adjacent to the instrumented spine were compared.
Results
Total 11 of 13 operated patients (85%) demonstrated degeneration of initially intact disks within the instrumented spine 2 years after the surgery. The signs included loss of disk height, sclerosis, and deformation of subchondral vertebral plates. Despite nobody had back pain, the main parents' complaint was the limitation of spine range of motion. We've decided to count the early symptoms of disk degeneration, the indication to remove spinal hardware having solid anterior fusion documented.
There was no increase of kyphosis, excluding one case of conjunctive deformity above the instrumented spine.
Conclusion
The intervertebral disks degeneration within the instrumented zone is a typical side effect of prolonged posterior rigid instrumentation in growing spine. After 2 years of surgery, it occurred in a majority of pediatric patients who had been operated due to the thoracic and lumbar spinal TB complicated by kyphosis exceeded 50ø. This degeneration was not accompanied by the pain during the childhood, but it may become symptomatic in adulthood.
Yes
None declared