Risk factors of instrumentation failure after multilevel total en bloc spondylectomy

Abstract

Abstract:Introduction: Multilevel total en bloc spondylectomy (TES) is required to secure oncologically adequate resection margins. However, no useful information has been reported for spinal reconstruction after multilevel TES. Therefore, this study set out to assess the clinical and radiological outcomes of spinal reconstruction after multilevel TES. Methods: Forty-eight patients treated with multilevel TES at our institute were included in the analysis. Reconstruction was achieved with posterior pedicle screw fixation and an anterior titanium mesh cage filled with iliac autograft in all cases. Spinal shortening was performed to increase spinal stability from the reconstruction. Instrumentation failure and radiological findings were evaluated with radiography and computerized tomography (CT). Results: After excluding one patient whose general condition was deteriorating, radiological evaluations of 47 patients were performed over a period of more than a year. The follow-up time was 17 to 120 months (mean: 70.2 months). Instrumentation failure occurred in one patient (5.9%) after thoracic multilevel TES, in 4 patients (25.0%) after thoracolumbar multilevel TES, and in 3 patients (42.9%) after lumbar multilevel TES. No instrumentation failure was observed in cervicothoracic cases. Cage subsidence (>2 mm) occurred in 30 patients (63.8%). In 22 of them, subsidence appeared on the CT one month after surgery. The risk factors of instrumentation failure included a multilevel TES below the thoracolumbar level and a long span of vertebral resection. There was no instrumentation failure in any of the 11 "disc-to-disc cutting" cases. Conclusions: This study identified the risk factors of instrumentation failure after multilevel TES. There is a high risk of instrumentation failure in cases of long vertebral resection below the thoracolumbar level. On the other hand, our reconstruction method can be successful for multilevel TES above the thoracic level.

Revision surgery for instrumentation failure after total en bloc spondylectomy: a retrospective case series

“…The previously reported incidence rate of instrumentation failure after TES using the same reconstruction method as ours (except using fresh autologous bone for bone grafting) was 17.0% (8/47) [11]; in the present study, the instrumentation failure rate after TES using frozen bone was 42.6% (26/61). It was reported that bone formation tended to be delayed when frozen bone autografts were used compared with fresh bone autografts [25]; therefore, the instrumentation failure rate in the present study was higher than that previously reported [11]. Although bone fusion was delayed, complete bone fusion within the cage was obtained in the TES model canine using frozen bone [25].…”

Total En Bloc Spondylectomy Combined with the Satellite Rod Technique for Spinal Tumors

“…A biomechanical study demonstrated that multi-segmental posterior xation with anterior column reconstruction can provide better stability than short xation and that xation should be extended to 2 ~ 3 levels above and below the resected vertebrae [23]. However, instrumentation failure, the incidence of which varies from 17.0-40%, is not a rare complication following a long-segment xation procedure after TES [7,13,24,25]. Among the types of IF, such as screw loosening, screw backout, cage breakage, screw fracture, and rod breakage, rod fracture is the most common and often leads to a high reoperation rate due to aggravating back pain or neurologic deterioration [9,24].…”

“…Among the types of IF, such as screw loosening, screw backout, cage breakage, screw fracture, and rod breakage, rod fracture is the most common and often leads to a high reoperation rate due to aggravating back pain or neurologic deterioration [9,24]. Cage subsidence, a history of radiotherapy, and a low spinal level of involvement have been con rmed to be risk factors related to rod fracture [7,9,24,25]. The survival time of spinal tumor patients is longer when primary tumors and metastatic tumors are resolved, so reconstruction of the three columns of the spine with additional posterior column reconstruction is very important [19].…”

“…Furthermore, satellite rods were cut from the long rod used in the operation, so this procedure did not increase the nancial burden of patients.. In addition, to prevent IF, several surgical techniques such as meticulous endplate preparation [9], TMC in the oblique position [24] and disc-to-disc cutting [25] are recommended.…”

Total en bloc spondylectomy combined with the satellite rod technique for spinal tumors

“…A biomechanical study demonstrated that multi-segmental posterior xation with anterior column reconstruction can provide better stability than short xation and that xation should be extended to 2~3 levels above and below the resected vertebrae [23]. However, instrumentation failure, the incidence of which varies from 17.0% to 40%, is not a rare complication following a long-segment xation procedure after TES [7,13,28,29]. Among the types of IF, such as screw loosening, screw back-out, cage breakage, screw fracture, and rod breakage, rod fracture is the most common and often leads to a high reoperation rate due to aggravating back pain or neurologic deterioration [9,28].…”