TY  - JOUR
A1  - König, Niklas
A1  - Cassel, Michael
A1  - Intziegianni, Konstantina
A1  - Mayer, Frank
T1  - Inter-rater reliability and measurement error of sonographic muscle architecture assessments
JF  - Journal of ultrasound in medicine
N2  - Objectives-Sonography of muscle architecture provides physicians and researchers with information about muscle function and muscle-related disorders. Inter-rater reliability is a crucial parameter in daily clinical routines. The aim of this study was to assess the inter-rater reliability of sonographic muscle architecture assessments and quantification of errors that arise from inconsistent probe positioning and image interpretation.
 Results-Inter-rater reliability was good overall (ICC, 0.77-0.90; IRV, 9.0%-13.4%; bias LoA, 0.2 +/- 0.2-1.7 +/- 3.0). Superior and inferior pennation angles showed high systematic bias and LoA in all setups, ranging from 2.0 degrees +/- 2.2 degrees to 3.4 degrees +/- 4.1 degrees. The highest IRV was found for muscle thickness (13.4%). "When the probe position was standardized, the SEM for muscle thickness decreased from 0.1 to 0.05 cm.
 Conclusions-Sonographic examination of muscle architecture of the medial gastrocnemius has good to high reliability. In contrast to pennation angle measurements, length measurements can be improved by standardization of the probe position.
KW  - gastrocnemius muscle
KW  - inter-rater variability
KW  - muscle architecture
KW  - musculoskeletal ultrasound
KW  - sonography
Y1  - 2014
U6  - https://doi.org/10.7863/ultra.33.5.769
SN  - 0278-4297
SN  - 1550-9613
VL  - 33
IS  - 5
SP  - 769
EP  - 777
PB  - American Institute of Ultrasound in Medicine
CY  - Laurel
ER  - 
TY  - CHAP
A1  - Intziegianni, Konstantina
A1  - Cassel, Michael
A1  - König, Niklas
A1  - Mayer, Frank
T1  - Reliability of variables defining mechanical and material properties of the achilles tendon
T2  - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine
Y1  - 2013
SN  - 0195-9131
SN  - 1530-0315
VL  - 45
IS  - 5
SP  - 238
EP  - 239
PB  - Lippincott Williams & Wilkins
CY  - Philadelphia
ER  - 
TY  - JOUR
A1  - Intziegianni, Konstantina
A1  - Cassel, Michael
A1  - König, Niklas
A1  - Müller, Steffen
A1  - Fröhlich, Katja
A1  - Mayer, Frank
T1  - Ultrasonography for the assessment of the structural properties of the Achilles tendon in asymptomatic individuals: An intra-rater reproducibility study
JF  - Isokinetics and exercise science : official journal of the European Isokinetic Society
N2  - BACKGROUND: Reproducible measurements of tendon structural properties are a prerequisite for accurate diagnosis of tendon disorders and for determination of their mechanical properties. Despite the widely used application of Ultrasonography (US) in musculoskeletal assessment, its operator dependency and lack of standardization influences the consistency of the measurement.
 OBJECTIVE: To evaluate the intra-rater reproducibility of a standardized US method assessing the structural properties of the Achilles tendon (AT).
 METHODS: Sixteen asymptomatic participants were positioned prone on an isokinetic dynamometer with the knee extended and ankle at 90. flexion. US was used to assess AT-length, cross-sectional area (CSA), and AT-elongation during isometric plantarflexion contraction. The intra-rater reproducibility was assessed by ICC (2.1), Test-Retest Variability (TRV, %), Bland-Altman analyses (Bias +/- LoA [1.96*SD]), and Standard-Error of Measurement (SEM).
 RESULTS: Measurements of AT-length demonstrated an ICC of 0.93, TRV of 4.5 +/- 3.9%, Bias +/- LoA of -2.8 +/- 25.0 mm and SEM of 6.6 mm. AT-CSA showed an ICC of 0.79, TRV of 8.7 +/- 9.6%, Bias +/- LoA of 1.7 +/- 19.4 mm(2) and SEM of 5.3 mm(2). AT-elongation revealed an ICC of 0.92, TRV of 12.9 +/- 8.9%, Bias +/- LoA of 0.3 +/- 5.7 mm and SEM of 1.5 mm.
 CONCLUSIONS: The presented methodology allows a reproducible assessment of Achilles tendon structural properties when performed by a single rater.
KW  - Ultrasonography
KW  - Achilles tendon
KW  - reproducibility
KW  - isokinetic
Y1  - 2015
U6  - https://doi.org/10.3233/IES-150586
SN  - 0959-3020
SN  - 1878-5913
VL  - 23
IS  - 4
SP  - 263
EP  - 270
PB  - IOS Press
CY  - Amsterdam
ER  -