Combination of sacral-alar-iliac screw and cortical bone trajectory screw techniques for lumbosacral fixation: technical note

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Lumbosacral fixation plays an important role in the management of devastating spinal pathologies, including osteoporosis, fracture, infection, tumor resection, and spinal deformities, which require long-segment fusion constructs to the sacrum. The sacral-alar-iliac (SAI) screw technique has been developed as a promising solution to facilitate both minimal invasiveness and strong fixation. The rationale for SAI screw insertion is a medialized entry point away from the ilium and in line with cranial screws. The divergent screw path of the cortical bone trajectory (CBT) provides a higher amount of cortical bone purchase and strong screw fixation and has the potential to harmoniously align with SAI screws due to its medial starting point. However, there has been no report on the combination of these two techniques. The objective of this study was to assess the feasibility of this combination technique.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The subjects consisted of 17 consecutive patients with a mean age of 74.2 ± 4.7 years who underwent posterior lumbosacral fixation for degenerative spinal pathologies using the combination of SAI and CBT fixation techniques. There were 8 patients with degenerative scoliosis, 7 with degenerative kyphosis, 1 with an osteoporotic vertebral fracture at L5, and 1 with vertebral metastasis at L5. Fusion zones included T10–sacrum in 13 patients, L2–sacrum in 2, and L4–sacrum in 2.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>No patients required complicated rod bending or the use of a connector for rod assembly in the lumbosacral region. Postoperative CT performed within a week after surgery showed that all lumbosacral screws were in correct positions and there was no incidence of neurovascular injuries. The lumbosacral bone fusion was confirmed in 81.8% of patients at 1-year follow-up based on fine-cut CT scanning. No patient showed a significant loss of spinal alignment or rod fracture in the lumbosacral transitional region.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>This is the first paper on the feasibility of a combination technique using SAI and CBT screws. This technique could be a valid option for lumbosacral fixation due to the ease of rod placement with potential reductions in operative time and blood loss.</jats:p></jats:sec>

Low profile posterior lumbar-sacral interbody fusion for lumbosacral degenerative diseases: A technical note

“…Achieving solid lumbosacral fusion has been a challenge for long-segment xation of the lumbosacral region due to the comparatively poor bone quality of the sacrum, complex anatomy, substantial biomechanical shear forces of the lumbosacral junction, and the prying effect caused by long-segment nailing rods [31]. These biomechanical characteristics induce a risk of pseudarthrosis and adjacent segment degeneration in this region, which may lead to failure of lumbosacral internal xation [32,33]. Since the introduction of the Galveston iliac xation instrument in 1982, emerging sacroiliac xation techniques, such as sacral alar screws (SASs), have been recognized as reliable xation methods for lumbosacral internal xation surgery [34].…”

Historical Note: The Evolution of Cortical Bone Trajectory and Associated Techniques

“…Lumbosacral fixation with long-segment fusion constructs to the sacrum can be an indication for spinal pathologies such as osteoporosis, fractures, infections, and tumors 52 . However, surgery to this area can be quite demanding and challenging owing to its complex anatomy, proximity to surrounding visceral structures, poor bone quality, and significant mechanical forces, thus leading to undesirable outcomes such as pseudoarthrosis, hardware failure, and loss of correction 53 .…”

“…In 2020, Matsukawa et al provided an interesting development in the CBT technique by combining it with the sacral-alar-iliac screw technique, producing a minimally invasive approach to sacral fixation. The sacral CBT trajectory was described to start more medial compared to conventional approaches and was directed anteriorly without convergence, penetrating the middle of the sacral endplate, thus engaging in dense sacral bone 52 . The authors discussed that the main advantages of this technique were as follows: (1) it allowed for ease of rod insertion, (2) it minimized the risk of rod fracture, (3) it required less lateral muscle dissection and thus decreased the risk of ischemic necrosis and denervation of posterior muscles, and 4) it had higher cortical purchase that resulted in superior biomechanical performance of this technique over conventional sacral fixation screws 52 .…”

A method of 3D‐3D multi‐stage non‐rigid registration of the spine based on binocular structured light

“…T HE insertion of the pedicle screw to fix the spine is called pedicle fixation 1,2 . With decades of technical development, internal fixation of pedicle screws has become a routine surgical procedure for the treatment of the spinal fracture in the lumbar 3 .…”

“…It can be seen from the above existing researches that the following two problems exist in the current research on spinal registration: (1) Intraoperative radiation injury to human body; (2) The accuracy of registration is decreased due to the deformation of The specific contributions of this article are listed as follows:…”