Evidence map›Paper›PMID 40678686›Full record

ArticleNorth American Spine Society journal2025

Insertional torque and pullout strength of reinserted screws for sacroiliac joint fusion: Effects of implant dimensions, bone density, and tapping.

Cale J Hendricks, David W Polly, Ashley M Abbott, Yaqoub Y Yusuf, Rafael A Garcia, Matthew R MacEwen, Arin M Ellingson

Abstract read
In one paragraph

Article in North American Spine Society journal, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

7 authors.

Cale J HendricksDepartment of Orthopedic Surgery, University of Minnesota, Minneapolis, MN, United States.
David W PollyDepartment of Orthopedic Surgery, University of Minnesota, Minneapolis, MN, United States.
Ashley M AbbottDepartment of Orthopedic Surgery, University of Minnesota, Minneapolis, MN, United States.
Yaqoub Y YusufDepartment of Family Medicine and Community Health, Divisions of Physical Therapy and Rehabilitation Science, University of Minnesota, Minneapolis, MN, United States.
Rafael A GarciaDepartment of Orthopedic Surgery, University of Minnesota, Minneapolis, MN, United States.
Matthew R MacEwenDepartment of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States.
Arin M EllingsonDepartment of Orthopedic Surgery, University of Minnesota, Minneapolis, MN, United States.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Sacroiliac joint (SIJ) fusion is a common procedure for SIJ pain and dysfunction. Traditional threaded screws offer limited bony integration, prompting the development of additively manufactured, porous implants aimed at enhancing osseointegration. However, data on their insertional mechanics and pullout strength, especially in revision scenarios, remain sparse. This study aimed to investigate the influence of bone density, tapping, and implant size on re-insertional torque and pullout strength. Methods: Mechanical testing was conducted in accordance with ASTM F543, using 10 and 20 PCF polyurethane foam blocks to simulate low and normal-density bone, respectively. A 10 × 35 mm screw fusion device served as the control. For subsequent tests, the 10 × 35 mm screw was removed, and various diameters (10, 11.5, 13.5 mm) and lengths (35, 40, 45 mm) were reinserted under 2 conditions: direct and with tapping. The maximum and final insertional torque, as well as the maximum pullout force, were measured. ANOVA techniques with pairwise comparison and Pearson correlation tests were performed (α = 0.05). Results: Significant effects and interactions were observed for implant size, bone density, and tapping. Larger implant diameter and length were associated with significantly greater insertional torque and pullout strength compared to controls, though excessively large diameters yielded diminishing returns in normal-density bone. Independent of size and tapping, normal-density bone consistently demonstrated greater insertional torque (929.1 ± 6.5 vs. 235.0 ± 6.5N·cm) and pullout strength (1,331.2 ± 14.8 vs. 457.3 ± 14.6 N) than low-density bone (p < .001). Independent of size, tapping improved insertional torque (+33.9%; p < .001) and pullout strength (+108.4%; p < .001) in normal-density bone but reduced pullout strength in low-density bone (-22.4%; p < .001). Final insertional torque strongly correlated with pullout strength (r = 0.946, p < .001). Conclusions: Our findings provide evidence-based insight for optimizing implant selection and surgical technique in revision SIJ fusion procedures using screw fusion devices. Particularly, it is emphasized that both implant dimensions and patient-specific bone quality must be considered to achieve stable and successful outcomes.

Indexed as

OsseointegrationPelvic screwPorous fusion/fixation screwPorous threaded implantScrew fusion device

Identifiers

PMID40678686
PMCPMC12269985

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.