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
Steven J. Obst, Lee Barber, Ashton Miller and Rod S. Barrett
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.
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.
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
Vincenzo Ricci and Levent Özçakar
and the allied health professional plan a specific rehabilitation program. In this sense, ultrasound (US) imaging is the first-level diagnostic tool that allows visualization of the hemorrhagic/edematous collection in an ideal time window of 36 to 48 hours after the trauma, and it can also be very
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
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
George Forrest and Kurt Rosen
Ultrasound is a commonly used modality of deep heating. Two techniques of application have been recommended: a technique in which the applicator head is applied directly to the subject and an immersion technique, The purpose of this study was to determine whether ultrasound treatments using the immersion technique in degassed water are as effective as ultrasound treatments using the direct technique of application in raising the temperature of periarticular structures into the therapeutic range. The limbs of a pig were treated with the direct and immersion techniques of application. Temperatures of the skin surface and of the extensor tendons of the ankle were taken before and after both methods of application. Treatments with the applicator head in direct contact with the limb of the subject were the more effective form of heating.
Laura C. Slane, Stijn Bogaerts, Darryl G. Thelen and Lennart Scheys
, 6 with lower peak stress and yield stress 7 than anterior (superficial) fascicles. However, many questions remain, including how such regional variations in tendon geometry and material properties may affect in vivo tendon behavior. Cine ultrasound imaging has emerged as a powerful tool for
Sarah Daniels, Gabriela Santiago, Jennifer Cuchna and Bonnie Van Lunen
Clinical Scenario Therapeutic ultrasound (US) is a popular modality among health care professionals and is used to treat a variety of musculoskeletal conditions. 1 Throughout the past 70 years of clinical use, 2 US has been shown to be an effective way to decrease pain, 2 , 3 increase tissue