Evidence map›Paper›PMID 39162957›Full record

ArticleSpine deformity2024

Effects of pelvic fixation strategies and multi-rod constructs on biomechanics of the proximal junction in long thoracolumbar posterior instrumented fusions: a finite-element analysis.

Muzammil Mumtaz, Andrew P Collins, Niloufar Shekouhi, Karthika Varier, Sudharshan Tripathi, Christopher P Ames, Vedat Deviren, Aaron J Clark, Vijay K Goel, Alekos A Theologis

Abstract read
In one paragraph

Article in Spine deformity, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Stabilization of L5 pedicle Subtraction osteotomies (PSO) with ≥ 6-rods and bilateral dual pelvic fixation with osseointegrative implants: surgical technique description and early postoperative outcomes.European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society · 2025
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Muzammil MumtazEngineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA.
Andrew P CollinsDepartment of Orthopaedics and Sports Medicine, University of Washington, Seattle, WA, USA.
Niloufar ShekouhiEngineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA.
Karthika VarierEngineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA.
Sudharshan TripathiEngineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA.
Christopher P AmesDepartment of Neurological Surgery, UCSF, San Francisco, CA, USA.
Vedat DevirenDepartment of Orthopaedic Surgery, University of California-San Francisco (UCSF), 500 Parnassus Ave, MUW 3rd Floor, San Francisco, CA, 94143, USA.
Aaron J ClarkDepartment of Neurological Surgery, UCSF, San Francisco, CA, USA.
Vijay K GoelEngineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA.
Alekos A TheologisDepartment of Orthopaedic Surgery, University of California-San Francisco (UCSF), 500 Parnassus Ave, MUW 3rd Floor, San Francisco, CA, 94143, USA. alekos.theologis@ucsf.edu.ORCID 0000-0001-6170-2813

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeTo assess the effect of various pelvic fixation techniques and number of rods on biomechanics of the proximal junction of long thoracolumbar posterior instrumented fusions.

methodsA validated spinopelvic finite-element (FE) model was instrumented with L5-S1 ALIF and one of the following 9 posterior instrumentation configurations: (A) one traditional iliac screw bilaterally ("2 Iliac/2 Rods"); (B) T10 to S1 ("Sacral Only"); (C) unilateral traditional iliac screw ("1 Iliac/2 Rods"); (D) one traditional iliac screw bilaterally with one midline accessory rod ("2 Iliac/3 rods"); (E) S2AI screws connected directly to the midline rods ("2 S2AI/2 Rods"); and two traditional iliac screws bilaterally with two lateral accessory rods connected to the main rods at varying locations (F1: T10-11, F2: T11-12, F3: T12-L1, F4: L1-2) ("4 Iliac/4 Rods"). Range of motions (ROM) at T10-S1 and T9-T10 were recorded and compared between models. The T9-T10 intradiscal pressures and stresses of the T9-10 disc's annulus in addition to the von Mises stresses of the T9 and T10 vertebral bodies were recorded and compared.

resultsFor T10-S1 ROM, 4 iliac/4 rods had lowest ROM in flexion and extension, while 2 S2AI/2 rods showed lowest ROM in rotation. Constructs with 3 or 4 rods had lower stresses on the primary rods compared to 2-rod constructs. At the proximal adjacent disc (T9-10), 4 iliac/4 rods showed lowest ROM, lowest intradiscal pressures, and lowest annular stress in all directions (most pronounced in flexion-extension). Under flexion and extension, 4 iliac/4 rods also showed the lowest von Mises stresses on the T10 vertebral body but the highest stresses on the T9 vertebral body.

conclusionsDual iliac screws with 4 rods across the lumbosacral junction and extending to the thoracolumbar junction demonstrated the lowest T10-S1 ROM, the lowest adjacent segment disc (T9-T10) ROM, intradiscal pressures, and annular stresses, and the lowest UIV stresses, albeit with the highest UIV + 1 stresses. Additional studies are needed to confirm whether these biomechanical findings dictate clinical outcomes and effect rates of proximal junctional kyphosis and failure.

Indexed as

Finite Element AnalysisLumbar VertebraeRange of Motion, ArticularSpinal FusionThoracic VertebraeBiomechanical PhenomenaBone ScrewsHumansPelvisBiomechanicsFinite-element analysisMulti-rod constructsPelvic fixationProximal junctional kyphosis/failure

Identifiers

PMID39162957
PMCPMC11499539

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LicenceCC BY
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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.