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Reliability of Achilles Tendon Moment Arm Measured In Vivo Using Freehand Three-Dimensional Ultrasound

Steven J. Obst, Lee Barber, Ashton Miller, and Rod S. Barrett

joint torque to AT force and can be measured in vivo using the ‘tendon-excursion method’ 1 or a ‘geometric method’. 2 The simplest geometric methods use 2D medical imaging (eg, sagittal magnetic resonance imaging [MRI] or B-mode ultrasound) in combination with anthropometric measurements 3 , 4 or 3D

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An Algorithm for Automated Analysis of Ultrasound Images to Measure Tendon Excursion in Vivo

Sabrina S.M. Lee, Gregory S. Lewis, and Stephen J. Piazza

The accuracy of an algorithm for the automated tracking of tendon excursion from ultrasound images was tested in three experiments. Because the automated method could not be tested against direct measurements of tendon excursion in vivo, an indirect validation procedure was employed. In one experiment, a wire “phantom” was moved a known distance across the ultrasound probe and the automated tracking results were compared with the known distance. The excursion of the musculotendinous junction of the gastrocnemius during frontal and sagittal plane movement of the ankle was assessed in a single cadaver specimen both by manual tracking and with a cable extensometer sutured to the gastrocnemius muscle. A third experiment involved estimation of Achilles tendon excursion in vivo with both manual and automated tracking. Root mean squared (RMS) error was calculated between pairs of measurements after each test. Mean RMS errors of less than 1 mm were observed for the phantom experiments. For the in vitro experiment, mean RMS errors of 8–9% of the total tendon excursion were observed. Mean RMS errors of 6–8% of the total tendon excursion were found in vivo. The results indicate that the proposed algorithm accurately tracks Achilles tendon excursion, but further testing is necessary to determine its general applicability.

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The Use of Normalized Cross-Correlation Analysis for Automatic Tendon Excursion Measurement in Dynamic Ultrasound Imaging

Stephen J. Pearson, Tim Ritchings, and Ahmad S.A. Mohamed

The work describes an automated method of tracking dynamic ultrasound images using a normalized cross-correlation algorithm, applied to the patellar and gastrocnemius tendon. Displacement was examined during active and passive tendon excursions using B-mode ultrasonography. In the passive test where two regions of interest (2-ROI) were tracked, the automated tracking algorithm showed insignificant deviations from relative zero displacement for the knee (0.01 ± 0.04 mm) and ankle (–0.02 ± 0.04 mm) (P > .05). Similarly, when tracking 1-ROI the passive tests showed no significant differences (P > .05) between automatic and manual methods, 7.50 ± 0.60 vs 7.66 ± 0.63 mm for the patellar and 11.28 ± 1.36 vs 11.17 ± 1.35 mm for the gastrocnemius tests. The active tests gave no significant differences (P > .05) between automatic and manual methods with differences of 0.29 ± 0.04 mm for the patellar and 0.26 ± 0.01 mm for the gastrocnemius. This study showed that automatic tracking of in vivo displacement of tendon during dynamic excursion under load is possible and valid when compared with the standardized method. This approach will save time during analysis and enable discrete areas of the tendon to be examined.

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Could Relative Movement Between the Adductor Muscles and the Skin Invalidate Surface Electromyography Measurement?

Walaa M. Elsais, Stephen J. Preece, Richard K. Jones, and Lee Herrington

muscle architecture. For example, ultrasound has been used to measure muscle thickness 15 and elongation of muscle and soft tissue structures during maximal 16 , 17 and submaximal contraction. 18 Two previous studies have used ultrasound to identify the boundaries of the individual adductor muscles

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Estimates of Achilles Tendon Moment Arm Length at Different Ankle Joint Angles: Effect of Passive Moment

Jared R. Fletcher and Brian R. MacIntosh

option in many cases. Consequently, a series of hybrid measurements similar to the MRI center of rotation method have been developed. These include measuring the perpendicular distance from the apparent center of rotation to Achilles tendon midpoint using motion analysis and ultrasound to detect the

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The Effects of Body Position on Trochanteric Soft Tissue Thickness—Implications for Predictions of Impact Force and Hip Fracture Risk During Lateral Falls

Benoit R. Lafleur, Alyssa M. Tondat, Steven P. Pretty, Marina Mourtzakis, and Andrew C. Laing

having direct measurements of TSTT in future studies. Ultrasound imaging is a practical tool that has previously been employed to enable direct measurement of TSTT. 22 , 35 – 38 This noninvasive approach offers several advantages including real-time imaging, high patient acceptability, as well as low

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Infraspinatus Cross-Sectional Area and Shoulder Range of Motion Change Following Live-Game Baseball Pitching

Brett S. Pexa, Eric D. Ryan, Elizabeth E. Hibberd, Elizabeth Teel, Terri Jo Rucinski, and Joseph B. Myers

last longer in muscles subjected to eccentric activity compared with concentric muscle action. 18 Anatomical muscle cross-sectional area (CSA), a 2-dimensional outline of the muscle belly as measured with musculoskeletal ultrasound, significantly increases following eccentric exercise 19 and remains

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Effects of Plyometric Training on Sonographic Characteristics of Quadriceps Muscle and Patellar Tendon, Quadriceps Strength, and Jump Height in Adolescent Female Volleyball Players

Gulcan Harput, Ugur Toprak, Fatma Filiz Colakoglu, Emirhan Temel, Suzan Saylisoy, and Gul Baltaci

extensor structures in adolescent athletes. Ultrasound is a quick, and cost-effective method to assess the morphological and structural benefits of plyometric training to determine if further training or modified training is necessary. It may provide clinicians with an alternative to simple strength

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Quadriceps Muscle Action and Association With Knee Joint Biomechanics in Individuals with Anterior Cruciate Ligament Reconstruction

Amanda E. Munsch, Alyssa Evans-Pickett, Hope Davis-Wilson, Brian Pietrosimone, and Jason R. Franz

production and altered knee joint biomechanics. We 24 and others 25 , 26 have recently used in vivo ultrasound imaging to demonstrate that the vastus lateralis (VL) in uninjured controls operates with little length change during weight acceptance. This outcome contradicts the longstanding assumption that

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Correlations Between Anthropometric Measures and Muscle Thickness Using Ultrasound Imaging

Mark A. Sutherlin, L. Colby Mangum, Jay Hertel, Susan A. Saliba, and Joseph M. Hart

abdominis muscle. ▸ Height times mass was the most consistent normalization variable for the lumbar multifidus muscle. Low back pain (LBP) is a condition of global significance that influences deeper musculature in the body, 1 – 19 but assessing these muscles is challenging. Ultrasound imaging (USI) is one