0
Technical Brief

Application of a Novel Measure of In Vivo Knee Joint Laxity

[+] Author and Article Information
J. C. Küpper

Department of Mechanical
and Manufacturing Engineering,
University of Calgary,
Calgary, AB T2N 1N4, Canada

L. Westover

Department of Mechanical and
Manufacturing Engineering,
University of Calgary,
Calgary, AB T2N 1N4, Canada

R. Frayne

Department of Radiology,Department of Clinical Neurosciences,
University of Calgary,
Calgary, AB T2N 1N4, Canada;
Seaman Family Centre,
Foothills Medical Centre,
Alberta Health Services,
Calgary, AB T2N 2T9, Canada

J. L. Ronsky

Professor
Department of Mechanical and
Manufacturing Engineering,
McCaig Centre for Joint Injury and Arthritis Research,
University of Calgary,
Calgary, AB T2N 1N4, Canada;
Department of Surgery,
Faculties of Kinesiology and Medicine,
Schulich School of Engineering,
Calgary, AB T2N 1N4, Canada;
Zymetrix—BOSE Biomaterials & Tissue Engineering
Technology Development Centre,
2500 University Drive NW,
Calgary, AB T2N 1N4, Canada
e-mail: jlronsky@ucalgary.ca

1Corresponding author.

Manuscript received September 11, 2015; final manuscript received July 7, 2016; published online August 8, 2016. Assoc. Editor: Kenneth Fischer.

J Biomech Eng 138(10), 104501 (Aug 08, 2016) (7 pages) Paper No: BIO-15-1448; doi: 10.1115/1.4034169 History: Received September 11, 2015; Revised July 07, 2016

Current measures of knee joint laxity, such as those found clinically using the KT-2000 arthrometer, are not highly repeatable or reliable by Huber et al. (1997, “Intratester and Intertester Reliability of the KT-1000 Arthrometer in the Assessment of Posterior Laxity of the Knee,” Am. J. Sports Med., 25(4), pp. 479–485). In this study, a noninvasive in vivo magnetic resonance (MR) imaging-based measure of laxity, the knee loading apparatus (KLA) with anterior positioning frame, was evaluated with five normal subjects (repeatability study, n = 3). Effects of hormones and muscle guarding were considered. When compared to the KT-2000, the KLA was found to be more precise (±0.33 mm versus ±1.17 mm) but less reliable (Cronbach's alpha > 0.70 in 0/8 versus 5/8 load levels). Improved control of the initial subject position is recommended for future design iterations. The KLA shows promise as an accurate and reliable tool for measuring in vivo joint and ligament laxity.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Flowchart for methods to obtain a measure of stiffness to quantify laxity with the KLA

Grahic Jump Location
Fig. 2

Knee loading apparatus (KLA) with anterior positioning frame with subject in position prior to magnetic resonance (MR) imaging

Grahic Jump Location
Fig. 3

The image data analysis process through digitization to obtain local joint coordinate systems, thin plate spline mappings of joint surfaces, and registration to match surfaces [20], combined to find anterior joint displacement

Grahic Jump Location
Fig. 4

EMG collected at a neutral position outside of the KLA

Grahic Jump Location
Fig. 5

KLA anterior force–displacement (S03) showing force ascending (open symbols) and descending (closed symbols) over three test days (D1, D2, and D3)

Grahic Jump Location
Fig. 6

Anterior tibial position at each force level for all the subjects on D1. ↑ indicates ascending portion of the curve, and ↓ indicates descending portion of the curve.

Grahic Jump Location
Fig. 7

Theoretical curve of force–displacement hysteresis. Each column of the table shows two force values (point 1 and point 2) for which a significant difference in anterior tibial displacement is observed (p ≤ 0.063). Arrows refer to ascending ↑ or descending ↓ portion of the curve (top figure).

Grahic Jump Location
Fig. 8

KT-2000 force–displacement (S02) showing filtered raw data across 3 days (D1, D2, and D3)

Grahic Jump Location
Fig. 9

KT-2000 force–displacement (S04) showing filtered raw data across three trials on 1 day (T1, T2, and T3). A typical shift of data over trials was observed (arrows). For all the subjects, the first full curve (T1) is used to assess KT-2000 data, shifted to 0 mm.

Grahic Jump Location
Fig. 10

Median displacement (box plot) at each load level for the KLA and KT-2000 (n = 5). ↑ indicates ascending portion of the curve, and ↓ indicates descending portion of the curve. (o indicates outliers, and * indicates extreme outliers).

Grahic Jump Location
Fig. 11

EMG signal as percentage of MVC for all the muscles (BF, GL, GM, RF, ST, VL, and VM) for all the subjects (n = 5). The X-axis crosses the Y-axis at 5% (o indicates outliers, and * indicates extreme outliers).

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In