TY - JOUR A1 - Cassel, Michael A1 - Müller, Steffen A1 - Carlsohn, Anja A1 - Baur, Heiner A1 - Jerusel, N. A1 - Mayer, Frank T1 - Intra- and interrater variability of sonographic investigations of patella and achilles tendons JF - Sportverletzung, Sportschaden : Grundlagen, Prävention, Rehabilitation N2 - Background: Clinical examinations of tendon disorders routinely include ultrasound examinations, despite the fact that availability of data concerning validity criteria of these measurements are limited. The present study therefore aims to evaluate the reliability of measurements of Achilles- and Patella tendon diameter and in the detection of structural adaptations. Materials and Methods: In 14 healthy, recreationally active subjects both asymptomatic Achilles (AT) and patella tendons (PT) were measured twice by two examiners in a test-retest design. Besides the detection of anteroposterior (a.p.-) and mediolateral (m.l.-) diameters, areas of hypoechogenicity and neovascularisation were registered. Data were analysed descriptively with calculation of test-retest variability (TRV), intraclass-correlation coefficient (ICC) and Bland and Altman's plots with bias and 95% limits of agreement (LOA). Results: Intra- and interrater differences of AT- and PT-a.p.-diameter varied from 0.2 - 1.2 mm, those of AT- and PT-m.l-diameter from 0.7-5.1 mm. Areas of hypoechogenicity were visible in 24% of the tendons, while 15% showed neovascularisations. Intrarater AT-a.p.-diameters showed sparse deviations (TRV 4.5-7.4%; ICC 0.60-0.84; bias -0.05-0.07 mm; LOA-0.6-0.5 to -1.1 - 1.0 mm), while interrater AT- and PT-m.l.-diameters were highly variable (TRV 13.7-19.7%; ICC 0.11-0.20; bias -1.4-4.3 mm; LOA-5.5-2.7 to -10.5 - 1.9 mm). Conclusion: Our results suggest that the measurement of AT- and PT-a.p.-diameters is a reliable parameter. In contrast, reproducibility of AT- and PT-m.l.-diameters is questionable. The study corroborates the presence of hypoechogenicity and neovascularisation in asymptomatic tendons. KW - ultrasound KW - Achilles tendon KW - Patella tendon KW - intra- and inter-rater variability KW - tendon diameter Y1 - 2012 U6 - https://doi.org/10.1055/s-0031-1281839 SN - 0932-0555 VL - 26 IS - 1 SP - 21 EP - 26 PB - Thieme CY - Stuttgart ER - TY - INPR A1 - Baur, Heiner A1 - Hoffmann, Jan A1 - Reichmuth, Anne A1 - Müller, Steffen A1 - Mayer, Frank T1 - Influence of carbon fiber foot orthoses on plantar pressure distribution in cycling T2 - Sportverletzung, Sportschaden : Grundlagen, Prävention, Rehabilitation N2 - Background: Several equipment interventions like optimizing seat position or optimizing shoe/insole/pedal interface are suggested to reduce overuse injury in cycling. Data analyzing clinical or biomechanical effects of those interventions is sparse. Foot orthoses out of carbon fiber are one possibility to alter the interface between foot and pedal. The aim of this study was therefore to analyze plantar pressure distribution in carbon fiber foot orthoses in comparison to standard insoles of commercially available cycling shoes. Materials and Methods: 11 pain-free triathletes (Age: 29 +/- 9, 1.77 +/- 0.04 m, 68 5 kg) were tested on a cycle ergometer at 60 and 90 rotations per minute (rpm) at workloads of 200 and 300 Watts. Subjects wore in randomized order a cycling shoe with its standard insole (control condition CO) or the shoe with carbon fiber foot orthoses (Condition CA). Mean peak pressure out of 30 movement cycles were extracted for the total foot and specific foot regions (rear, mid, fore foot (medial, central, lateral) and toe region). Three-factor ANOVAs (factor foot orthoses, rpm, workload) for repeated measures (alpha = 0.05) were used to analyze the main question of a foot orthoses effect on peak in-shoe plantar pressure. Results: Peak pressures in the total foot were in a range of 70-75 kPa for 200 Watts (W) (300 W: 85-110 kPa). The carbon fiber foot orthoses reduced peak pressures by -4,1% compared to the standard insole (p = 0,10). In the foot regions rear(-16,6%, p<0.001), mid (-20,0%, p<0.001) and fore foot (-5.9%, p < 0.03)CA reduced peak pressure compared to CO. In the toe region, peak pressure was higher in CA (+16,2%) compared to CO (p<0,001). The lateral fore foot showed higher peak pressures in CA (+34%) and CO (+59%) compared to medial and central fore foot. Conclusion: Carbon fiber can serve as a suitable material for foot orthoses manufacturing in cycling. Plantar pressures do not increase due to the stiffness of the carbon. Individual customization may have the potential to reduce peak pressure in certain foot areas. KW - Carbon KW - Cycling KW - Foot orthoses KW - In-shoe measurement KW - Plantar Pressure Distribution Y1 - 2012 SN - 0932-0555 VL - 26 IS - 1 SP - 12 EP - 17 PB - Thieme CY - Stuttgart ER - TY - THES A1 - Müller, Steffen T1 - Die belastungsspezifische neuromuskuläre Antwort bei Athleten mit Tendinopathie der Achilles- oder Patellarsehne : Analysen der funktionalen und therapeutischen Effekte eines sensomotorischen Trainings T1 - Neuromuscular response to physical stress in athletes with tendinopathie of the achilles- or patellartendon : funktional and therapeutic effects of an sensorimotor training N2 - Tendinopathien der Achilles- oder Patellarsehne sind häufig in Sportarten mit zahlreichen repetitiven Belastungen im Dehnungs-Verkürzungs-Zyklus der unteren Extremität zu finden. Sowohl eine möglicherweise alterierte belastungsspezifische neuromuskuläre Antwort (NMA), als auch funktional begründete Therapiemaßnahmen mit möglichen positiven Effekten sind aktuell ungeklärt. Ziel der Arbeit war deshalb die Untersuchung der belastungsspezifischen neuromuskulären Antwort bei Athleten mit Tendinopathie der Achilles- oder Patellarsehne im Vergleich zu beschwerdefreien Athleten. Zusätzlich sollten mögliche funktionale und therapeutische Effekte eines sensomotorischen Trainings im randomisierten, kontrollierten und prospektiven Studiendesign überprüft werden. 51 Sportler mit unilateraler Tendinopathie (Achilles-/Patellarsehne n = 35/16) und 33 gesunde Sportler wurden zur Beurteilung der belastungsspezifischen neuromuskulären Antwort eingeschlossen. Zur Klärung der Effekte eines sensomotorischen Trainings im Längsschnitt konnten 26 Sportler mit Tendinopathie randomisiert zu einer Kontrollgruppe (n = 14) und einer Therapiegruppe mit sensomotorischem Training (n = 12) zugeordnet werden. Nach einer ersten biomechanischen Messung M1 (Belastungssituationen: Lauf-, Stabilisations-, Kraftbelastung) und der Erhebung der subjektiven Schmerzsymptomatik folgte eine 8-wöchige Therapiephase mit einer abschließenden Re-Test-Messung M2 identisch zu M1. Das sensomotorische Training war auf die gesamte untere Extremität ausgerichtet und wurde nach Einweisung regelmäßig kontrolliert. Die Erfassung der NMA erfolgte über die Quantifizierung der muskulären Aktivität (EMG). Zusätzlich wurde die Kinetik (z.B. Maximalkraft) belastungsspezifisch erfasst. Eine reduzierte NMA konnte für die Sportler mit Tendinopathie über veränderte EMG-Zeit- und Amplitudenmessgrößen, eine reduzierte aktive Stabilisationsfähigkeit und Maximalkraft (p < 0,05) nachgewiesen werden. In Abhängigkeit der Lokalisation (Achilles-/Patellarsehen) bzw. der Seite (Beschwerdeseite/gesunde Seite) ergaben sich keine relevanten Differenzen. Das sensomotorische Training zeigte eine Optimierung der NMA (z.B. erhöhte Maximalkraft) bei Tendinopathie der Achilles- oder Patellarsehne. Die Überprüfung der Beschwerdesymptomatik wies in allen Schmerz-Scores nach der Therapie reduzierte Werte und damit einen positiven therapeutischen Effekt gegenüber der Kontrollgruppe auf. Zusammenfassend kann eine systematisch reduzierte NMA bei Lauf-, Stabilisations- und Kraftbelastung der Sportler mit Tendinopathie nachgewiesen werden. Das sensomotorische Training ist funktional und therapeutisch als effiziente Therapiemaßnahme zu erachten. N2 - Tendinopathies of the achilles- or patellartendon are common overuse unjuries in sports including high numbers of repetitive stretch-shortening-cycles of the lower limb. Possible alterations of the neuromuscular response (NMR) to physical stress and functionally justified therapies with potential positive effects are currently unknown. The aim of the study was therefore the analysis of the neuromuscular response in situations with physical stress in athletes with tendinopathie of the achilles or patellartendon compared to symptom free athletes. In addition, possible functional and therapeutic effects of a sensorimotor training were studied in a prospective, randomized and controlled study. 51 athletes with unilateral tendinopathy (achilles-/patellartendon n = 35/16) and 33 healthy athletes were included to assess the stress related neuromuscular response (NMR). To clarify the effects of a sensorimotor training 26 athletes with tendinopathy were randomized to a control group (n = 14) and a therapy group with sensorimotor training (n = 12). After initial biomechanical measurements M1 (situations: running, active postural stability and maximum strength test) and the collection of subjective complaints (pain) an 8-week treatment phase followed with a final re-test M2 measure identical to M1. The sensorimotor training was arranged for the entire lower extremity, and was checked after an initial briefing on a regular basis. The assessment of the NMR was quantified by muscle activity (EMG). In addition, the kinetics (e.g. maximum force) was acquired in the stabilization and maximum strength test. A reduced NMR could be proven for athletes with tendinopathy with changed EMG time and amplitude measurements, a reduced active postural stabilization ability and reduced maximum strength (p <0.05). No relevant differences could be observed in comparing localization (achilles-/patellartendon) and side (leg with complains/healthy leg). The sensorimotor training showed an optimization of NMR (e.g. increased maximum strength) for patient with tendinopathy of the achilles- or patellartendon. The examination of the complaints showed reduced values in all pain scores after therapy. The treatment had therefore positive therapeutic effects compared to the control group. In summary, a systematically reduced NMR in running, stabilization and strength tests are evident for athletes with tendinopathy. The sensorimotor training can be considered as an efficient treatment with functional and therapeutic effects. KW - Tendinopathie KW - neuromuskuläre Kontrolle KW - sensomotorisches Training KW - Reliabilität KW - tendinopathy KW - neuromuscular control KW - sensorimotor training KW - reproducibility Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16454 SN - 978-3-940793-18-8 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Müller, Steffen A1 - Baur, Heiner A1 - Hirschmueller, Anja A1 - Mayer, Frank T1 - Validität des COP-Verlaufes zur Quantifizierung der funktionalen Gangentwicklung bei Kindern N2 - Functional gait development in children is discussed controversially. Differentiated information about the roll- over process of the foot, represented by the "Center of Pressure" (COP), are still missing. The purpose of the study was the validation of the COP-path to quantify the functional gait development of children. Plantar pressure distribution was measured barefoot with an individual speed on a walkway (tartan) - in 255 children aged between 2 and 15 years. The medial and lateral area enclosed between the COP-path and the bisection of plantar angle (A(med), A(lat), Sigma: A(ml)) was calculated from plantar pressure data. Furthermore, the duration of the COP-path in the heel (COPtimeF), midfoot (COPtimeM) and forefoot (COPtimeV) was analysed. The load distribution under the medial and lateral forefoot was also calculated. The variation coefficient (VC) was calculated as a measure of interindividual variability. The medio-lateral divergency of the COP (Aml) initially decreases with advancing age (-20.2%), followed by a continuous increase (+27.2%). No changes in VC (A(med), A(lat), and A(ml)) appeared during age-related development. COPtimeM remains constant in all children over time. In contrast to COPtimeM, Cop(time)F decreases from youngest to oldest children (-31.0%), and COPtimeV increases (+41.7%). After initial descent up to 8 years of age, VC (COPtimeF, COPtimeM, COPtimeV) remains constant. The mediolateral load under the forefoot did not change. The COP-Path is able to characterise the functional gait development of children. VC values indicate high individual variability of gait pattern. In this context, age-based standard values should be critically discussed Y1 - 2006 ER -