Objective Our study aimed to compare the posterior interposition technique against the posterolateral transosseous technique in the same cadaver specimens.
Methods Computer and cadaver models of 2 fixation techniques were developed. The computer model was constructed to analyze bone volume removed during implant placement and the bony surface area available for fusion. The cadaver model included quasi-static multidirectional bending flexibility and dynamic fatigue loading. Relative motions between the sacrum and ilium were measured intact, after joint destabilization, after fixation with direct-posterior and posterolateral techniques, and after 18,500 cycles of fatigue loading. Relative positions between each implant and the sacrum and ilium were measured after fixation and fatigue loading to ascertain the quality of the bone-implant interface. The 2 techniques were randomized to the left and right sacroiliac joints of the same cadavers.
Results The posterior interposition technique removed less bone volume and facilitated a larger surface area available for bony fusion. Posterior interposition significantly reduced the nutation/counternutation motion of the sacroiliac joint (42% ± 8%) and reduced it more than the posterolateral transosseous technique (14% ± 4%). Upon fatigue loading, the posterior interposition implant maintained the bone-implant interface across all specimens, while the posterolateral transosseous implant migrated or subsided in 20%–50% of specimens.
Conclusion Posterior interposition fixation of the sacroiliac joint reduces joint motion. The amount of fixation from the posterior technique is superior and more durable than the amount of fixation achieved by the posterolateral technique.
Citations
Citations to this article as recorded by
Sacroiliac joint fixation with a posterior intra-articular implant versus a posterolateral transiliac implant: A biomechanical comparison Connor Huxman, Joshua Tandio, Douglas Beall, Sarah Mayer, Adam Rogers, Thomas P. Hedman, Jonathan A. Hyde, Usman Latif, Richard Oluwatodimu Raji, Jeremi M. Leasure North American Spine Society Journal (NASSJ).2026; 26: 100871. CrossRef
Best practices for the LinQ sacroiliac joint stabilization procedure for the treatment of sacroiliac joint disorders Timothy Deer, Anuj Shah, David Reece, Chau M. Vu, Siddardth Umapathy, Harman Chopra, Colin Mark Buday, Rosa A. Garcia, Johnson S. Ho, Robin Mata, Christopher M. Lam, Christopher L. Robinson, Lucas Bracero, Mateusz Graca, Casey Grillo, Ashley G. Comer, Kas Pain Management.2026; 16(7): 809. CrossRef
A Retrospective, Multicenter Analysis of a Novel Sacroiliac Joint Fusion Device on Safety and Efficacy at 12 Months: Access Study Michael J. Dorsi, Pankaj Mehta, Chau Vu, Angel Boev, Ashley Bailey-Classen, Greg Moore, David Reece, Alaa Abd-Elsayed, Steven Falowski, Jason E. Pope Healthcare.2025; 13(13): 1544. CrossRef
Optimal screw insertion trajectory for sacroiliac joint fusion surgery: An evolutionary and growth process perspective on the sacroiliac joint Daisuke Kurosawa, Kouji Sanaka, Eiichi Murakami Medical Hypotheses.2025; 202: 111730. CrossRef
Bernardo de Andrada Pereira, Jennifer N. Lehrman, Anna G.U. Sawa, Piyanat Wangsawatwong, Jakub Godzik, David S. Xu, Jay D. Turner, Brian P. Kelly, Juan S. Uribe
Neurospine 2022;19(3):828-837. Published online September 30, 2022
Objective The high mechanical stress zone at the sudden transition from a rigid to flexible region is involved in proximal junctional kyphosis (PJK) physiopathology. We evaluated the biomechanical performance of polyetheretherketone (PEEK) rods used as a nontraditional long semirigid transition phase from a long-segment metallic rod construct to the nonfused thoracic spine.
Methods Pure moment range of motion (ROM) tests (7.5 Nm) were performed on 7 cadaveric spine segments followed by compression (200 N). Specimens were tested in the following conditions: (1) intact; (2) T10-pelvis pedicle screws and rods (PSRs); and (3) extending the proximal construct to T6 using PEEK rods (PSR+PEEK). T10–11 rod strain, T9 anterolateral bone strain, and T10 screw bending moments were analyzed.
Results At the upper instrumented vertebra (UIV)+1, PSR+PEEK versus PSR significantly decreased ROM in flexion (115%, p = 0.02), extension (104%, p = 0.003), left lateral bending (46%, p = 0.02), and right lateral bending (63%, p = 0.008). Also, at UIV+1, PSR+PEEK versus intact significantly decreased ROM in flexion (111%, p = 0.01) and extension (105%, p = 0.003). The UIV+1 anterior column bone strain was significantly reduced with PSR+PEEK versus PSR during right lateral bending (p = 0.02). Rod strain polarities reversed with PEEK rods in all loading directions except compression.
Conclusion Extending a long-segment construct using PEEK rods caused a decrease in adjacent-level hypermobility as a consequence of long-segment immobilization and also redistributed the strain on the UIV and adjacent levels, which might contribute to PJK physiopathology. Further studies are necessary to observe the clinical outcomes of this technique.
Citations
Citations to this article as recorded by
Evaluation of Screw Loosening in Patients Undergoing Semi-rigid Stabilization with Polyetheretherketone (PEEK) Rods Nimetullah Alper Durmus, Ali Sahin, Sukru Oral, Halil Ulutabanca, Ahmet Kucuk, Rahmi Kemal Koc Indian Journal of Orthopaedics.2026; 60(6): 1537. CrossRef
Proximal Junctional Kyphosis Prevention in Adult Spinal Deformity Surgery: A Technical Review of Tethering and Adjunctive Strategies Paritash Tahmasebpour, Pawel P. Jankowski, Jason Liang, Joshua Lin, Kyriakos D. Chatzis, Peter S. Tretiakov, Spencer Matthews, Louis Boissiere, John F. Burke, Christopher I. Shaffrey, Aaron Hockley, Peter Passias Operative Neurosurgery.2026;[Epub] CrossRef
Relationship Between the Elastic Modulus of the Novel Pedicle Screw-Plate System and Biomechanical Properties Under Osteoporotic Condition: A Power-Law Regression Analysis Based on Parametric Finite Element Simulations Kaibin Wang, Chongyi Wang, Haipeng Si, Yanwei Zhang, Shaowei Sang, Runtong Zhang, Wencan Zhang, Junfei Chen, Chen Liu, Kunpeng Li, Bingtao Hu, Xiangyu Lin, Yunze Feng, Qingyang Fu, Zhihao Kang, Mingyu Xu, Dingxin Zhang, Wanlong Xu, Le Li Computer Methods and Programs in Biomedicine.2025; 265: 108760. CrossRef
Optimizing Surgical Strategies for Preventing Proximal Junctional Complications: A Systematic Review and Meta-analysis of Operative Techniques in Adult Spinal Deformity HyungSub Jin, Kyung-Soo Suk, Byung Ho Lee, Si Young Park, Hak-Sun Kim, Seong-Hwan Moon, Sub-Ri Park, Namhoo Kim, Jae Won Shin, Ji-Won Kwon Neurospine.2025; 22(4): 1012. CrossRef
A Biomechanical Comparison of 2 Different Topping-off Devices and Their Influence on the Sacroiliac Joint Following Lumbosacral Fusion Surgery Wei Fan, Song Yang, Jie Chen, Li-Xin Guo, Ming Zhang Neurospine.2024; 21(1): 244. CrossRef
Application of Transverse Process Hooks at Distal Thoracic Vertebrae in Uppermost Vertebral Instrumentation for Adult Spinal Deformity Surgery: Special Focus on Delayed-Onset Neurologic Deficits Sun-Joon Yoo, Hyun-Jun Jang, Bong Ju Moon, Jeong-Yoon Park, Sung Uk Kuh, Dong-Kyu Chin, Keun-Su Kim, Jun Jae Shin, Yoon Ha, Kyung-Hyun Kim Neurospine.2024; 21(4): 1219. CrossRef
Comparison of Cortical Bone Trajectory to Pedicle-Based Dynamic Stabilization: An Analysis of 291 Patients Chih-Chang Chang, Hsuan-Kan Chang, Chin-Chu Ko, Ching-Lan Wu, Yi-Hsuan Kuo, Tsung-Hsi Tu, Wen-Cheng Huang, Jau-Ching Wu Neurospine.2023; 20(1): 308. CrossRef
Pelvic Incidence–Lumbar Lordosis Mismatch Is Predisposed to Adjacent Segment Degeneration After Single-Level Anterior Lumbar Interbody Fusion: A Retrospective Case-Control Study Sun Geon Yoon, Hyung Chang Lee, Sang-Min Lee Neurospine.2023; 20(1): 301. CrossRef
To describe the biomechanically relevant anatomy of the Axis vertebra and the load transfer patterns within the bone, and on that basis, to postulate its mechanism of injury, a literature review was conducted of the anatomy and biomechanics of Axis fractures. Two hypotheses have been presented: the internal gear hypothesis and the leaf spring hypothesis. Both are based on the trabecular anatomy of the vertebra and its load transmission patterns. The relationship of the Axis with Hangman’s injury is also discussed. According to the leaf spring hypothesis, the C2 pedicle corresponds to the shackle in the assembly and constitutes the weak link. The trabecular architecture of the Axis is such that the primary compression of the trabeculae is directed from the superior facet to the C2–3 endplate, with few trabeculae directed to the inferior facet. Along with the trabecular void in this area, this renders the isthmus vulnerable to trauma. The isthmus of the Axis is biomechanically susceptible to injury due to its unique anatomy in relation to the whole cervical spine and the internal load transmission patterns of the bone. The author suggests that in the flexion type of Hangman’s injury, the C1–2 posterior ligaments are disrupted and need to be addressed.
Citations
Citations to this article as recorded by
Understanding cervical spine instability: a finite element study on atypical hangman’s fractures Dávid Danka, Imre Bojtár Computer Methods in Biomechanics and Biomedical Engineering.2026; 29(4): 930. CrossRef
Superior articular facet angulation of the axis vertebra in a South African population sample using an osteological analysis Shahed Nalla, Isabel Harmse, Juan A. Sanchis-Gimeno, Juan José Valenzuela-Fuenzalida, Glen J. Paton Translational Research in Anatomy.2026; 43: 100493. CrossRef
Biomechanical evaluation of the novel assembled internal fixed system in C2–C3 anterior cervical discectomy and fusion: a finite element analysis Hu Chen, Hao Sun, Lu Cao, Hong Xia, Qiang Tu Journal of Orthopaedic Surgery and Research.2024;[Epub] CrossRef
Hangman’s Fractures: A Review of Current Concepts in Evaluation and Management Joshua Mizels, James W. Connelly, Nicholas Spina, Brandon Lawrence, Brian A. Karamian Clinical Spine Surgery.2024; 37(9): 365. CrossRef
Detailed observation of anatomical location and pattern in Hangman’s fracture based on computed tomography three-dimensional reconstruction Guangzhou Li, Qing Wang Journal of Orthopaedic Surgery and Research.2023;[Epub] CrossRef
The participation of basolateral amygdala in the efficacy of acupuncture with deqi treating for functional dyspepsia Ruirui Sun, Zhaoxuan He, Peihong Ma, Shuai Yin, Tao Yin, Xiaoyan Liu, Jin Lu, Yuzhu Qu, Tingting Zhang, Liuyang Huang, Xueling Suo, Du Lei, Qiyong Gong, Fanrong Liang, Fang Zeng Brain Imaging and Behavior.2021; 15(1): 216. CrossRef
Efficiency of minimal oblique resection of the uncinate process during an anterior cervical discectomy and fusion Byoung Hun Lee, Jong Hwa Park, Jong Young Lee, Hong Jun Jeon, Seung-Woo Park Medicine.2021; 100(31): e26790. CrossRef
Anterior retropharyngeal cage distraction with atlantoaxial plate-screw fixation for basilar invagination with atlantoaxial dislocation Sushil Patkar Neurosurgical Focus: Video.2020; 3(1): V11. CrossRef