Effective measurement of knee alignment using AP knee radiographs
Effective measurement of knee alignment using AP knee radiographs
The gold standard for measuring knee alignment is mechanical axis determined using full-limb radiographs (FLR). Measurement of joint alignment using antero-posterior (AP) knee radiographs is more accessible, economical and involves less radiation exposure to the patient compared with using full-limb radiographs. The aim of this study was to compare and assess the reproducibility of knee joint axial alignment on full-limb radiographs and conventional AP knee radiographs.
Knee alignment was measured in 40 subjects (80 knees) from the TwinsUK registry. Measurement of mechanical knee alignment was from FLR, and anatomic knee alignment from weight-bearing AP knee radiographs. Reproducibility was assessed by intra-class correlation coefficients and kappa statistics. Reproducibility of knee alignment for both methods was good, with intra-observer ICC's of 0.99 for both FLR
and AP radiographs. The mean alignment angle on FLR was 178.9° (SD 2.1, range 173–183°), and 179.0° (SD 2.1, range 173–185°) on AP films. 58.8% of knees on FLR and 66.3% on AP films were of varus alignment. Good correlations were seen between results for FLR and AP radiographs, with ICC ranging from 0.87–0.92 for left and right knees, and kappa statistics of 0.65–0.74. Standard AP knee radiographs can be used to measure knee alignment with good reproducibility, and
provide comparable results to those obtained from FLR. This will facilitate measurement of knee alignment in existing cohort studies to assess malalignment as a risk factor of incident OA, and in clinical practice.
knee osteoarthritis, alignment, knee radiograph, epidemiology
42-45
Colebatch, Alexandra N.
9739b630-ba0f-45b1-b2ad-f176faf2d909
Hart, Deborah J.
4f5ca470-3877-4d29-b0ab-4127bdf8b361
Zhai, Guangju
9108920e-4990-4b43-908f-cf0bbe1be909
Williams, F.M.
2bf15d00-c3b4-4255-8a3c-df12b6a64716
Spector, Tim D.
1e47066c-6620-4f86-af6f-89d9e130ffc2
Arden, Nigel K.
23af958d-835c-4d79-be54-4bbe4c68077f
January 2009
Colebatch, Alexandra N.
9739b630-ba0f-45b1-b2ad-f176faf2d909
Hart, Deborah J.
4f5ca470-3877-4d29-b0ab-4127bdf8b361
Zhai, Guangju
9108920e-4990-4b43-908f-cf0bbe1be909
Williams, F.M.
2bf15d00-c3b4-4255-8a3c-df12b6a64716
Spector, Tim D.
1e47066c-6620-4f86-af6f-89d9e130ffc2
Arden, Nigel K.
23af958d-835c-4d79-be54-4bbe4c68077f
Colebatch, Alexandra N., Hart, Deborah J., Zhai, Guangju, Williams, F.M., Spector, Tim D. and Arden, Nigel K.
(2009)
Effective measurement of knee alignment using AP knee radiographs.
The Knee, 16 (1), .
(doi:10.1016/j.knee.2008.07.007).
Abstract
The gold standard for measuring knee alignment is mechanical axis determined using full-limb radiographs (FLR). Measurement of joint alignment using antero-posterior (AP) knee radiographs is more accessible, economical and involves less radiation exposure to the patient compared with using full-limb radiographs. The aim of this study was to compare and assess the reproducibility of knee joint axial alignment on full-limb radiographs and conventional AP knee radiographs.
Knee alignment was measured in 40 subjects (80 knees) from the TwinsUK registry. Measurement of mechanical knee alignment was from FLR, and anatomic knee alignment from weight-bearing AP knee radiographs. Reproducibility was assessed by intra-class correlation coefficients and kappa statistics. Reproducibility of knee alignment for both methods was good, with intra-observer ICC's of 0.99 for both FLR
and AP radiographs. The mean alignment angle on FLR was 178.9° (SD 2.1, range 173–183°), and 179.0° (SD 2.1, range 173–185°) on AP films. 58.8% of knees on FLR and 66.3% on AP films were of varus alignment. Good correlations were seen between results for FLR and AP radiographs, with ICC ranging from 0.87–0.92 for left and right knees, and kappa statistics of 0.65–0.74. Standard AP knee radiographs can be used to measure knee alignment with good reproducibility, and
provide comparable results to those obtained from FLR. This will facilitate measurement of knee alignment in existing cohort studies to assess malalignment as a risk factor of incident OA, and in clinical practice.
This record has no associated files available for download.
More information
Published date: January 2009
Keywords:
knee osteoarthritis, alignment, knee radiograph, epidemiology
Identifiers
Local EPrints ID: 69447
URI: http://eprints.soton.ac.uk/id/eprint/69447
ISSN: 0968-0160
PURE UUID: e6045157-90e7-4f0a-98c6-3f7e83924c44
Catalogue record
Date deposited: 05 Nov 2009
Last modified: 13 Mar 2024 19:33
Export record
Altmetrics
Contributors
Author:
Alexandra N. Colebatch
Author:
Deborah J. Hart
Author:
Guangju Zhai
Author:
F.M. Williams
Author:
Tim D. Spector
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics