TY - JOUR A1 - Bisi-Balogun, Adebisi A1 - Rector, Michael V. T1 - Clinical Utility of Ultrasound Measurements of Plantar Fascia Width and Cross-Sectional Area BT - a novel technique JF - Journal of the American Podiatric Medical Association N2 - Background: We sought to develop a standardized protocol for ultrasound (US) measurements of plantar fascia (PF) width and cross-sectional area (CSA), which may serve as additional outcome variables during US examinations of both healthy asymptomatic PF and in plantar fasciopathy and determine its interrater and intrarater reliability. Methods: Ten healthy individuals (20 feet) were enrolled. Participants were assessed twice by two raters each to determine intrarater and interrater reliability. For each foot, three transverse scans of the central bundle of the PF were taken at its insertion at the medial calcaneal tubercle, identified in real time on the plantar surface of the foot, using a fine wire technique. Reliability was determined using intraclass correlation coefficients (ICC), standard errors of measurement (SEM), and limits of agreement (LOA) expressed as percentages of the mean. Reliability of PF width and CSA measurements was determined using PF width and CSA measurements from one sonogram measured once and the mean of three measurements from three sonograms each measured once. Results: Ultrasound measurements of PF width and CSA showed a mean of 18.6 +/- 2.0 mm and 69.20 +/- 13.6 mm(2) respectively. Intra-reliability within both raters showed an ICC. 0.84 for width and ICC. 0.92 for CSA as well as a SEM% and LOA%, 10% for both width and CSA. Inter-rater reliability showed an ICC of 0.82 for width and 0.87 for CSA as well as a SEM% and LOA%, 10% for width and a SEM%, 10% and LOA%, 20% for CSA. Relative and absolute reliability within and between raters were higher when using the mean of three sonographs compared to one sonograph. Conclusions: Using this novel technique, PF CSA and width may be determined reliably using measurements from one sonogram or the mean of three sonograms. Measurement of PF CSA and width in addition to already established thickness and echogenicity measurements provides additional information on structural properties of the PF for clinicians and researchers in healthy and pathologic PF. Y1 - 2017 U6 - https://doi.org/10.7547/16-042 SN - 8750-7315 SN - 1930-8264 VL - 107 IS - 5 SP - 375 EP - 381 PB - Amer podiatric med assoc CY - Bethesda ER - TY - JOUR A1 - Wippert, Pia-Maria A1 - Rector, Michael V. A1 - Kuhn, Gisela A1 - Wuertz-Kozak, Karin T1 - Stress and Alterations in Bones BT - An Interdisciplinary Perspective JF - Frontiers in endocrinology N2 - Decades of research have demonstrated that physical stress (PS) stimulates bone remodeling and affects bone structure and function through complex mechanotransduction mechanisms. Recent research has laid ground to the hypothesis that mental stress (MS) also influences bone biology, eventually leading to osteoporosis and increased bone fracture risk. These effects are likely exerted by modulation of hypothalamic–pituitary–adrenal axis activity, resulting in an altered release of growth hormones, glucocorticoids and cytokines, as demonstrated in human and animal studies. Furthermore, molecular cross talk between mental and PS is thought to exist, with either synergistic or preventative effects on bone disease progression depending on the characteristics of the applied stressor. This mini review will explain the emerging concept of MS as an important player in bone adaptation and its potential cross talk with PS by summarizing the current state of knowledge, highlighting newly evolving notions (such as intergenerational transmission of stress and its epigenetic modifications affecting bone) and proposing new research directions. KW - biomechanics KW - bone–brain–nervous system interactions KW - endocrine pathways KW - osteoporosis KW - exercise Y1 - 2017 U6 - https://doi.org/10.3389/fendo.2017.00096 SN - 1664-2392 VL - 8 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Rector, Michael V. A1 - Intziegianni, Konstantina A1 - Müller, Steffen A1 - Mayer, Frank A1 - Cassel, Michael T1 - Reproducibility of an ankle joint rotation correction method for assessment of Achilles tendon elongation JF - Isokinetics and exercise science : official journal of the European Isokinetic Society N2 - BACKGROUND: The Achilles tendon (AT) requires optimal material and mechanical properties to function properly. Calculation of these properties depends on accurate measurement of input parameters (i.e. tendon elongation). However, the measurement of AT elongation with ultrasound during maximum voluntary isometric contraction (MVIC) is overestimated by ankle joint rotation (AJR). Methods to correct the influence of this rotation on AT elongation exist, yet their reproducibility in clinical settings is unknown. OBJECTIVE: To evaluate the test-retest reproducibility of AT elongation during MVIC after AJR correction. METHODS: Ten participants attended test and retest measurements where they performed plantar-flexion MVIC on a dynamometer. Simultaneously, ultrasound recorded AT elongation as the displacement of the medial gastrocnemius-myotendinous junction, while an electrogoniometer measured AJR. The ankle was then passively rotated to the AJR achieved during MVIC and AT elongation again determined. Elongation was corrected by subtracting this passive AT elongation from the total AT elongation during MVIC. Reproducibility was evaluated using ICC (2.1), test-retest variability (TRV, %), Bland-Altman analyses (Bias +/- LoA [1.96*SD]) and standard error of the measurement (SEM). RESULTS: Corrected AT elongation reproducibility exhibited an ICC = 0.79, SEM = 0.2 cm and TRV = 20 +/- 19%. Bias +/- LoA were determined to be 0.0 +/- 0.8 cm. CONCLUSIONS: Using this ultrasound and electrogoniometer-based method, corrected AT elongation can be assessed reproducibly. KW - Ultrasonography KW - Achilles tendon KW - reproducibility KW - isokinetic KW - ankle joint rotation Y1 - 2017 U6 - https://doi.org/10.3233/IES-160644 SN - 0959-3020 SN - 1878-5913 VL - 25 IS - 1 SP - 47 EP - 52 PB - IOS Press CY - Amsterdam ER - TY - JOUR A1 - Müller, Juliane A1 - Müller, Steffen A1 - Stoll, Josefine A1 - Rector, Michael V. A1 - Baur, Heiner A1 - Mayer, Frank T1 - Influence of Load on Three-Dimensional Segmental Trunk Kinematics in One-Handed Lifting: A Pilot Study JF - Journal of applied biomechanics N2 - Stability of the trunk is relevant in determining trunk response to different loading in everyday tasks initiated by the limbs. Descriptions of the trunk’s mechanical movement patterns in response to different loads while lifting objects are still under debate. Hence, the aim of this study was to analyze the influence of weight on 3-dimensional segmental motion of the trunk during 1-handed lifting. Ten asymptomatic subjects were included (29 ± 3 y; 1.79 ± 0.09 m; 75 ± 14 kg). Subjects lifted 3× a light and heavy load from the ground up onto a table. Three-dimensional segmental trunk motion was measured (12 markers; 3 segments: upper thoracic area [UTA], lower thoracic area [LTA], lumbar area [LA]). Outcomes were total motion amplitudes (ROM;[°]) for anterior flexion, lateral flexion, and rotation of each segment. The highest ROM was observed in the LTA segment (anterior flexion), and the smallest ROM in the UTA segment (lateral flexion). ROM differed for all planes between the 3 segments for both tasks (P < .001). There were no differences in ROM between light and heavy loads (P > .05). No interaction effects (load × segment) were observed, as ROM did not reveal differences between loading tasks. Regardless of weight, the 3 segments did reflect differences, supporting the relevance of multisegmental analysis. KW - trunk motion KW - kinematic trunk model KW - everyday task KW - MiSpEx* Y1 - 2016 U6 - https://doi.org/10.1123/jab.2015-0227 SN - 1065-8483 SN - 1543-2688 VL - 32 SP - 520 EP - 525 PB - Human Kinetics Publ. CY - Champaign ER - TY - JOUR A1 - Intziegianni, Konstantina A1 - Cassel, Michael A1 - Rauf, S. A1 - White, S. A1 - Rector, Michael V. A1 - Kaplick, Hannes A1 - Wahmkow, Gunnar A1 - Kratzenstein, S. A1 - Mayer, Frank T1 - Influence of Age and Pathology on Achilles Tendon Properties During a Single-leg Jump JF - International journal of sports medicine N2 - Prevalence of Achilles tendinopathy increases with age leading to a weaker tendon with predisposition to rupture. Conclusive evidence of the influence of age and pathology on Achilles tendon (AT) properties remains limited, as previous studies are based on standardized isometric conditions. The study investigates the influence of age and pathology on AT properties during single-leg vertical jump (SLVJ). 10 children (C), 10 asymptomatic adults (A), and 10 tendinopathic patients (T) were included. AT elongation [mm] from rest to maximal displacement during a SLVJ on a force-plate was sonographically assessed. AT compliance [mm/N]) and strain [%] was calculated by dividing elongation by peak ground reaction force [N] and length, respectively. One-way ANOVA followed by Bonferroni post-hoc correction (=0.05) were used to compare C with A and A with T. AT elongation (p=0.004), compliance (p=0.001), and strain were found to be statistically significant higher in C (27 +/- 3mm, 0.026 +/- 0.006[mm/N], 13 +/- 2%) compared to A (21 +/- 4mm, 0.017 +/- 0.005[mm/N], 10 +/- 2%). No statistically significant differences (p0.05) was found between A and T (25 +/- 5mm, 0.019 +/- 0.004[mm/N], 12 +/- 3%). During SLVJ, tendon responded differently in regards to age and pathology with children having the most compliant AT. Higher compliance found in healthy tendons might be considered as a protective factor against load-related injuries. KW - children KW - tendinopathy KW - compliance KW - dynamic KW - ultrasonography Y1 - 2016 U6 - https://doi.org/10.1055/s-0042-108198 SN - 0172-4622 SN - 1439-3964 VL - 37 SP - 973 EP - 978 PB - Thieme CY - Stuttgart ER - TY - CHAP A1 - Rector, Michael V. A1 - Ottawa, Fabian A1 - Wang, Victor A1 - Wippert, Pia-Maria T1 - Test-retest reliability of hair cortisol concentration and correlations with physical activity levels in non-athletes T2 - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine Y1 - 2014 SN - 0195-9131 SN - 1530-0315 VL - 46 IS - 5 SP - 222 EP - 222 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - CHAP A1 - Wippert, Pia-Maria A1 - De Witt Huberts, Jessie A1 - Honold, Jasmin A1 - Holzmann, Caroline A1 - Rector, Michael V. A1 - Mayer, Frank T1 - Chronic stress measurement methods and their comparability T2 - Psychosomatic medicine Y1 - 2014 SN - 0033-3174 SN - 1534-7796 VL - 76 IS - 3 SP - A129 EP - A129 PB - Lippincott Williams & Wilkins CY - Philadelphia ER -