Objective: The purpose was to analyze how rod characteristics, screw density and cages influence the incidence of mechanical complications compared to patient-related factors and alignment in adult spinal deformity instrumented T9-T11 to pelvis.
Methods: Register data of 302 patients was analyzed. Relative lumbar lordosis (RLL) and relative sagittal alignment (RSA) was measured. Surgical data included rod characteristics, pedicle screw density and interbody cages. Univariate and multivariate logistic regression models were used.
Results: Pseudarthrosis occurred in 24.1%. On univariate analysis Odds Ratio (OR) was 0.74 for ≥ 3 cages (p = 0.452), 0.48 for 4 rods (p = 0.008), 4.30 for high screw density (p = 0.001). Patient-related factors were non-significant. Multivariate OR was 0.59 for 4 rods (p = 0.084) and 4.67 for high screw density (p = 0.005). PJK/PJF occurred in 19.2%. Age > 60 had an OR 2.83 (p = 0.023), postoperative RSA malaligned OR 2.84 (p = 0.030), severely malaligned OR 6.54 (p < 0.001). Implant characteristics were non-significant. Multivariate OR was 1.26 for age > 60 (p = 0.657), 2.32 for malaligned RSA (p = 0.097), 5.69 for severely malaligned RSA (p = 0.001). Screw loosening occurred in 8.9%. Univariate OR was 0.95 for ≥ 3 cages (p = 0.920), 1.64 for 4 rods (p = 0.235), 0.25 for high screw density 1.5-2 (p = 0.011). Patient-related factors were non-significant. Multivariate OR for high screw density was 0.23 (p = 0.022).
Conclusion: Four rods decrease the pseudarthrosis risk. Cages have a secondary role. High screw density doesn't prevent from pseudarthrosis. Postoperative malalignment is the main PJK/PJF risk factor. Age plays a secondary role. Implant characteristics have a minor influence. High screw density constructs have a lower risk for screw loosening.
Level Of Evidence: 3-Retrospective register study.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s00586-024-08543-9 | DOI Listing |
Microsc Microanal
January 2025
Université de Lorraine, CNRS, Arts et Métiers, LEM3, Metz 57070, France.
Characterizing threading dislocations (TDs) in gallium nitride (GaN) semiconductors is crucial for ensuring the reliability of semiconductor devices. The current research addresses this issue by combining two techniques using a scanning electron microscope, namely electron channeling contrast imaging (ECCI) and high-resolution electron backscattered diffraction (HR-EBSD). It is a comparative study of these techniques to underscore how they perform in the evaluation of TD densities in GaN epitaxial layers.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Orthopedic Surgery, Chang Gung Memorial Hospital, No. 5, Fuxing St., Guishan Dist, Linkou, Taoyuan, 33305, Taiwan.
Objective: To investigate the predictive ability of the MRI-based vertebral bone quality (VBQ) score for pedicle screw loosening following instrumented transforaminal lumbar interbody fusion (TLIF).
Methods: Data from patients who have received one or two-level instrumented TLIF from February 2014 to March 2015 were retrospectively collected. Pedicle screw loosening was diagnosed when the radiolucent zone around the screw exceeded 1 mm in plain radiographs.
J Orthop Surg Res
January 2025
Department of Orthopaedic Surgery, Spine Section, Bone and Joint Research Center, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
Objective: Combining oblique lumbar interbody fusion (OLIF) with posterior pedicle screw fixation (PPSF) has been proposed to reduce cage subsidence, especially in osteoporotic spines. Recently, anterolateral screw-rod fixation has gained interest as it allows direct pathology observation and avoids a posterior approach. However, controversies exist between anterolateral screw fixation systems and traditional PPSF due to variations in osteoporotic vertebral mineral density, screw fixation positions, and fixation methods (bicortical vs.
View Article and Find Full Text PDFClin Spine Surg
December 2024
Department of Orthopaedic Surgery, Keio University School of Medicine, Shinjyuku, Tokyo.
Study Design: Multicenter retrospective cohort study.
Objective: To evaluate the efficacy and safety of using cement-augmented pedicle screw (CAPS) fixation only for the cephalad and caudal vertebral bodies.
Summary Of Background Data: Pedicle screw fixation is less effective in patients with low-quality bone.
Asian Spine J
December 2024
National Spinal Injuries Unit, Mater Misericordiae University Hospital, Dublin, Ireland.
Computed tomography (CT) is widely used for the diagnosis and surgical treatment of spinal pathologies, particularly for pedicle screw placement. However, CT's limitations, notably radiation exposure, necessitate the development of alternative imaging techniques. Synthetic CT (sCT), which generates CT-like images from existing magnetic resonance imaging (MRI) scans, offers a promising alternative to reduce radiation exposure.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!