Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Search research articles

Related Experiment Video

Updated: Jun 21, 2026

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

Published on: October 9, 2014

Objective guidelines for removing an external fixator after tibial lengthening using pixel value ratio: a pilot

Li Zhao¹, Qing Fan, K P Venkatesh

¹Department of Pediatric Orthopaedics, Xin-Hua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Clinical Orthopaedics and Related Research

|August 7, 2009

Summary

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Two families with spondylo-epi-metaphyseal dysplasia due to compound heterozygocity in the vWFA domain of MATN3.

European journal of medical genetics·2024

Same author

Novel loss-of-function variants of TRAPPC2 manifesting X-linked spondyloepiphyseal dysplasia tarda: report of two cases.

BMC medical genetics·2019

Same author

Isolated Dislocation of Fourth Carpometacarpal Joint: Case Report.

The journal of hand surgery Asian-Pacific volume·2017

Same author

Juxtaphyseal Intraosseous Hemangioma of Proximal Femur causing Coxa vara and Coxa breva deformity in a growing child.

Journal of orthopaedic case reports·2016

Same author

Complications of the Intramedullary Skeletal Kinetic Distractor (ISKD) in distraction osteogenesis.

Clinical orthopaedics and related research·2014

Same author

A case of metatropic dysplasia: operative treatment of severe kyphoscoliosis and limb deformities.

Oman medical journal·2013

Objective radiographic criteria using pixel value ratio can guide external fixator removal and weightbearing after limb lengthening. This method aims to prevent complications like nail breakage and refracture.

Area of Science:

Orthopedic Surgery
Biomedical Imaging
Regenerative Medicine

Background:

Limb lengthening decisions rely on subjective radiographic callus assessment.
Objective callus evaluation is needed to prevent complications like hardware failure and refracture.

Purpose of the Study:

To determine the radiographic criteria for external fixator removal and weightbearing post-limb lengthening.
To establish objective callus measurement using pixel value ratio.

Main Methods:

Retrospective review of 17 patients (34 tibial lengthenings) over intramedullary nails.
Radiographic analysis using pixel value ratio (regenerate vs. adjacent bone).

Main Results:

Partial weightbearing allowed with a pixel value ratio of 1 in two cortices.

More Related Videos

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

Published on: March 24, 2019

Related Experiment Videos

Last Updated: Jun 21, 2026

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

Published on: October 9, 2014

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

Published on: March 24, 2019

Full weightbearing permitted with a pixel value ratio of 1 in three cortices.

No nail or screw breakage or refracture observed in the study cohort.

Conclusions:

Pixel value ratio offers an objective method for callus assessment in limb lengthening.
Radiographic criteria using pixel value ratio may guide external fixator removal timing.
Established criteria were associated with no subsequent refractures in this cohort.