Evidence map›Paper›PMID 27689140›Full record

ArticleScoliosis and spinal disorders2016

Flexible growing rods: a biomechanical pilot study of polymer rod constructs in the stability of skeletally immature spines.

Donita I Bylski-Austrow, David L Glos, Anne C Bonifas, Max F Carvalho, Matthew C Coombs, Peter F Sturm

Open access · hybridAbstract read
In one paragraph

Article in Scoliosis and spinal disorders, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
0.3field-weighted citation impact, top 35% of its field
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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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

4 citing papers in PubMed, 8 citations in OpenAlex.

  1. Article
  2. Article
  3. Current benchtop protocols are not appropriate for the evaluation of distraction-based growing rods: a literature review to justify a new protocol and its development.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 · 2022
    Review
  4. Review
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

6 authors at 2 institutions in 1 country.

Donita I Bylski-AustrowOrthopaedics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039 USA ; University of Cincinnati, Cincinnati, OH USA.
David L GlosOrthopaedics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039 USA.
Anne C BonifasOrthopaedics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039 USA.
Max F CarvalhoOrthopaedics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039 USA.
Matthew C CoombsUniversity of Cincinnati, Cincinnati, OH USA.
Peter F SturmOrthopaedics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039 USA ; University of Cincinnati, Cincinnati, OH USA.
Cincinnati Children's Hospital Medical Center · USUniversity of Cincinnati · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSurgical treatments for early onset scoliosis (EOS) correct curvatures and improve respiratory function but involve many complications. A distractible, or 'growing rod,' implant construct that is more flexible than current metal rod systems may sufficiently correct curves in small children and reduce complications due to biomechanical factors. The purpose of this pilot study was to determine ranges of motion (ROM) after implantation of simulated growing rod constructs with a range of clinically relevant structural properties. The hypothesis was that ROM of spines instrumented with polymer rods would be greater than conventional metal rods and lower than non-instrumented controls.

methodsBiomechanical tests were conducted on six thoracic spines from skeletally immature domestic swines (35-40 kg). Paired pedicle screws were used as anchors at proximal and distal levels. Specimens were tested under the following conditions: control, then dual rods of polyetheretherketone (PEEK) (diameter 6.25 mm), titanium (4 mm), and cobalt-chrome alloy (CoCr) (5 mm). Lateral bending (LB) and flexion-extension (FE) moments were applied, and vertebral rotations were measured. Differences were determined by two-tailed t-tests and Bonferroni for four primary comparisons: PEEK vs control and PEEK vs CoCr, in LB and FE (α = 0.05/4).

resultsIn LB, ROM of spine segments after instrumenting with PEEK rods was lower than the non-instrumented control condition at each instrumented level. ROM was greater with PEEK rods than with Ti and CoCr rods at every instrumented level. Combining treated levels, in LB, ROM for PEEK rods was 35 % of control (p < 0.0001) and 270 % of CoCr rods (p < 0.01). In FE, ROM with PEEK was 27 % of control (p < 0.001) and 180 % of CoCr (p < 0.01). At proximal and distal adjacent non-instrumented levels in FE, mean ROM was lower for PEEK than for either metal.

conclusionsPEEK rods increased flexibility versus metal rods, and decreased flexibility versus non-instrumented controls, both over the entire instrumented segment and at each individual level. Smaller mean increases in ROM at proximal and distal adjacent motion segments occurred with PEEK compared to metal rods, which may help decrease complications, such as junctional kyphosis. Flexible growing rods may eventually help improve treatment options for young patients with severe deformity.

Indexed as

BiomechanicsCobalt chrome alloyEarly onset scoliosisGrowing rodsPEEK rodsPolyetheretherketonePolymerRange of motionSpine instrumentationTitanium

Identifiers

PMID27689140
PMCPMC5034591
OpenAlexW2465949390

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.