Selection of the fusion and fixation range in the intervertebral surgery to correct thoracolumbar and lumbar tuberculosis: a retrospective clinical study

Background To compare the diseased verses the non-diseased intervertebral surgery used in the treatment of thoracolumbar and lumbar spinal tuberculosis and to explore the best choice of fusion of fixation range. Methods Two hundred twenty-one patients with thoracolumbar and lumbar tuberculosis were categorized into two groups. One hundred eighteen patients underwent the diseased intervertebral surgery (lesion vertebral pedicle fixation, Group A) and 103 patients underwent the non-diseased intervertebral surgery (1 or 2 vertebral fixation above and below the affected vertebra, group B). Spinal tuberculosis diagnosis was confirmed in both groups of patients before lesion removal, bone graft fusion, and internal fixation. Clinical data and efficacy of the two surgical methods were then evaluated. Results The mean follow-up duration for both procedures was 65 months (50–68 months range). There were no significant differences in laboratory examinations, VAS scores, and the Cobb angle correction rate and the angle loss. However, significant differences existed in the operation time, blood loss, serosanguineous drainage volume, and blood transfusion requirement between the two groups. The diseased intervertebral surgery group performed significantly better than the non-diseased intervertebral surgery group in all of these areas. In both cases, the bone graft fused completely with the normal bone by the last follow-up, occuring at 50–86 months post surgery. Conclusion The diseased intervertebral surgery is a safe and feasible option for the treatment of thoracolumbar and lumbar tuberculosis. It effectively restores the physiological curvature of the spine and reduces the degeneration of adjacent vertebral bodies in the spinal column.

Biomechanics of artificial pedicle fixation in a 3D-printed prosthesis after total en bloc spondylectomy: a finite element analysis

Background This study compared the biomechanics of artificial pedicle fixation in spine reconstruction with a 3-dimensional (3D)-printed prosthesis after total en bloc spondylectomy (TES) by finite element analysis. Methods A thoracolumbar (T10–L2) finite element model was developed and validated. Two models of T12 TES were established in combination with different fixation methods: Model A consisted of long-segment posterior fixation (T10/11, L1/2) + 3D-printed prosthesis; and Model B consisted of Model A + two artificial pedicle fixation screws. The models were evaluated with an applied of 7.5 N·m and axial force of 200 N. We recorded and analyzed the following: (1) stiffness of the two fixation systems, (2) hardware stress in the two fixation systems, and (3) stress on the endplate adjacent to the 3D-printed prosthesis. Results The fixation strength of Model B was enhanced by the screws in the artificial pedicle, which was mainly manifested as an improvement in rotational stability. The stress transmission of the artificial pedicle fixation screws reduced the stress on the posterior rods and endplate adjacent to the 3D-printed prosthesis in all directions of motion, especially in rotation. Conclusions After TES, the posterior long-segment fixation combined with the anterior 3D printed prosthesis could maintain postoperative spinal stability, but adding artificial pedicle fixation increased the stability of the fixation system and reduced the risk of prosthesis subsidence and instrumentation failure.

Biomechanics of artificial pedicle fixation in a 3D-printed prosthesis after total en bloc spondylectomy: A finite element analysis

Background: This study compared the biomechanics of artificial pedicle fixation in spine reconstruction with a 3-dimensional (3D)-printed prosthesis after total en bloc spondylectomy (TES) by finite element analysis.Methods: A thoracolumbar (T10–L2) finite element model was developed and validated. Two models of T12 TES were established in combination with different fixation methods: Model A consisted of long-segment posterior fixation (T10/11, L1/2) + 3D-printed prosthesis; and Model B consisted of Model A + two artificial pedicle fixation screws. The models were evaluated with an applied of 7.5 N·m and axial force of 200 N. We recorded and analyzed the following: 1) stiffness of the two fixation systems; 2) hardware stress in the two fixation systems; and 3) stress on the endplate adjacent to the 3D-printed prosthesis.Results: The fixation strength of Model B was enhanced by the screws in the artificial pedicle, which was mainly manifested as an improvement in rotational stability. The stress transmission of the artificial pedicle fixation screws reduced the stress on the posterior rods and endplate adjacent to the 3D-printed prosthesis in all directions of motion, especially in rotation.Conclusions: After TES, the posterior long-segment fixation combined with the anterior 3D printed prosthesis could maintain postoperative spinal stability, but adding artificial pedicle fixation increased the stability of the fixation system and reduced the risk of prosthesis subsidence and instrumentation failure.

Selection of the Fusion and Fixation Range in the Intervertebral Surgery to Correct Thoracolumbar and Lumbar Tuberculosis：A Retrospective Clinical Study

Background To compare the diseased verses the non-diseased intervertebral surgery used in the treatment of thoracolumbar and lumbar spinal tuberculosis and to explore the best choice of fusion of fixation range.Methods 221 patients with thoracolumbar and lumbar tuberculosis were categorized into two groups. 118 patients underwent the diseased intervertebral surgery (lesion vertebral pedicle fixation, Group A) and 103 patients underwent the non-diseased intervertebral surgery (1 or 2 vertebral fixation above and below the affected vertebra, group B). Spinal tuberculosis diagnosis was confirmed in both groups of patients before lesion removal, bone graft fusion, and internal fixation. Clinical data and efficacy of the two surgical methods were then evaluated. Results The mean follow-up duration for both procedures was 65 months (50-68 months range). There were no significant differences in laboratory examinations,VAS scores, and the Cobb angle correction rate and the angle loss. However, significant differences existed in the operation time, blood loss, serosanguineous drainage volume, and blood transfusion requirement between the two groups. The diseased intervertebral surgery group performed significantly better than the non-diseased intervertebral surgery group in all of these areas. In both cases, the bone graft fused completely with the normal bone by the last follow-up, occuring at 50-86 months post surgery.Conclusion The diseased intervertebral surgery is a safe and feasible option for the treatment of thoracolumbar and lumbar tuberculosis. It effectively restores the physiological curvature of the spine and reduces the degeneration of adjacent vertebral bodies in the spinal column.

Prone Transpsoas Technique for Simultaneous Single-Position Access to the Anterior and Posterior Lumbar Spine

BACKGROUND Effective decompression, arthrodesis, and correction of spinal conditions frequently utilize operative approaches that expose both the anterior and posterior spinal column. Until now, circumferential spinal column access often requires the surgeon to reposition and drape the patient multiple times or utilize a posterior only approach that has limited anterior correction capability or to utilize a lateral-only approach that complicates otherwise traditional posterior surgical maneuvers. OBJECTIVE To describe a technique utilizing a single surgical position that enables minimally disruptive anterior column correction with simultaneous access to the posterior spinal column. METHODS The operative technique for accessing the lateral lumbar interbody space from a prone transpsoas (PTP) approach is described. The rationale for this approach and a representative case example are reviewed. RESULTS The PTP approach was used to perform an L3-4 and L4-5 interbody fusion in a 71-yr-old female with spondylolisthesis, severe stenosis, and locked facets. The PTP approach enabled efficient completion of an anterior column correction, direct posterior decompression, multi-segment pedicle fixation, and maintenance of alignment, all while in a single prone position. There were no intraoperative or postoperative complications. CONCLUSION The authors’ early experience with the described PTP technique suggests it is not only feasible but offers some advantages, as it allows for single-position surgery maximizing both anterior and posterior column access and corrective techniques. Further follow-up studies of this technique are ongoing.

Biomechanics of Artificial Pedicle Fixation in a 3d-printed Prosthesis After Total en Bloc Spondylectomy: A Finite Element Analysis

Background: This study compared the biomechanics of artificial pedicle fixation in spine reconstruction with a 3-dimensional (3D)-printed prosthesis after total en bloc spondylectomy (TES) by finite element analysis.Methods: A thoracolumbar (T10–L2) finite element model was developed and validated. Two models of T12 TES were established in combination with different fixation methods: Model A consisted of long-segment posterior fixation (T10/11, L1/2) + 3D-printed prosthesis; and Model B consisted of Model A + two artificial pedicle fixation screws. The models were evaluated with an applied of 7.5 N·m and axial force of 200 N. We recorded and analyzed the following: 1) stiffness of the two fixation systems; 2) hardware stress in the two fixation systems; and 3) stress on the endplate adjacent to the 3D-printed prosthesis.Results: The fixation strength of Model B was enhanced by the screws in the artificial pedicle, which was mainly manifested as an improvement in rotational stability. The stress transmission of the artificial pedicle fixation screws reduced the stress on the posterior rods and endplate adjacent to the 3D-printed prosthesis in all directions of motion, especially in rotation.Conclusions: After TES, the posterior long-segment fixation combined with the anterior 3D printed prosthesis could maintain postoperative spinal stability, but adding artificial pedicle fixation increased the stability of the fixation system and reduced the risk of prosthesis subsidence and instrumentation failure.