TY - JOUR A1 - Appiah-Dwomoh, Edem Korkor A1 - Müller, Steffen A1 - Mayer, Frank T1 - Is there an association between variables of static and dynamic postural control in adolescent athletes with back pain? T1 - Gibt es einen Zusammenhang zwischen Variablen der statischen und dynamischen posturalen Kontrolle bei Nachwuchsathleten mit Rückenschmerzen? JF - German Journal of Exercise and Sport Research N2 - An association between static and dynamic postural control exists in adults with back pain. We aimed to determine whether this association also exists in adolescent athletes with the same condition. In all, 128 athletes with and without back pain performed three measurements of 15s of static (one-legged stance) and dynamic (star excursion balance test) postural control tests. All subjects and amatched subgroup of athletes with and without back pain were analyzed. The smallest center of pressure mediolateral and anterior-posterior displacements (mm) and normalized highest reach distance were the outcome measures. No association was found between variables of the static and dynamic tests for all subjects and the matched group with and without back pain. The control of static and dynamic posture in adolescent athletes with and without back pain might not be related. N2 - Bei Erwachsenen mit Rückenschmerzen besteht ein Zusammenhang zwischen statischer und dynamischer posturaler Kontrolle. Ziel der Studie war es zu untersuchen, ob dieser Zusammenhang auch bei Nachwuchsathleten mit Rückenschmerzen nachweisbar ist. Insgesamt 128 Nachwuchsathleten mit oder ohne Rückenschmerzen führten je 3 Messungen à 15 s eines statischen (einbeiniger Standtest) bzw. dynamischen („star excursion balance test“ [SEBT]) posturalen Kontrolltests durch. In die Auswertung wurden sowohl die gesamte Stichprobe als auch eine gematchte Untergruppe einbezogen. Zielparameter waren der kleinste mediolaterale und anterior-posteriore Schwankungsweg im Einbeinstand (mm) und die normierte maximal erreichte Distanz im SEBT. Es wurden keine Zusammenhänge zwischen Variablen der statischen und dynamischen Tests für alle Studienteilnehmer und der gematchten Untergruppe mit und ohne Rückenschmerzen festgestellt. Obwohl ein Zusammenhang zwischen statischer und dynamischer posturaler Kontrolle angenommen wird, konnte dieser bei Nachwuchsathleten mit oder ohne Rückenschmerzen nicht nachgewiesen werden. KW - Postural control KW - Adolescent athletes KW - Back pain KW - One-legged stance KW - Star excursion balance test KW - Posturale Kontrolle KW - Nachwuchsathleten KW - Rückenschmerzen KW - Einbeiniger Standtest Y1 - 2019 U6 - https://doi.org/10.1007/s12662-019-00573-6 SN - 2509-3142 SN - 2509-3150 VL - 49 IS - 2 SP - 150 EP - 155 PB - Springer CY - New York ER - TY - GEN A1 - Cassel, Michael A1 - Müller, Juliane A1 - Moser, Othmar A1 - Strempler, Mares Elaine A1 - Reso, Judith A1 - Mayer, Frank T1 - Orthopedic Injury Profiles in Adolescent Elite Athletes BT - A Retrospective Analysis From a Sports Medicine Department T2 - Postprints der Universität Potsdam Humanwissenschaftliche Reihe N2 - Aim: The aim of the study was to identify common orthopedic sports injury profiles in adolescent elite athletes with respect to age, sex, and anthropometrics. Methods: A retrospective data analysis of 718 orthopedic presentations among 381 adolescent elite athletes from 16 different sports to a sports medical department was performed. Recorded data of history and clinical examination included area, cause and structure of acute and overuse injuries. Injury-events were analyzed in the whole cohort and stratified by age (11–14/15–17 years) and sex. Group differences were tested by chi-squared-tests. Logistic regression analysis was applied examining the influence of factors age, sex, and body mass index (BMI) on the outcome variables area and structure (a = 0.05). Results: Higher proportions of injury-events were reported for females (60%) and athletes of the older age group (66%) than males and younger athletes. The most frequently injured area was the lower extremity (47%) followed by the spine (30.5%) and the upper extremity (12.5%). Acute injuries were mainly located at the lower extremity (74.5%), while overuse injuries were predominantly observed at the lower extremity (41%) as well as the spine (36.5%). Joints (34%), muscles (22%), and tendons (21.5%) were found to be the most often affected structures. The injured structures were different between the age groups (p = 0.022), with the older age group presenting three times more frequent with ligament pathology events (5.5%/2%) and less frequent with bony problems (11%/20.5%) than athletes of the younger age group. The injured area differed between the sexes (p = 0.005), with males having fewer spine injury-events (25.5%/34%) but more upper extremity injuries (18%/9%) than females. Regression analysis showed statistically significant influence for BMI (p = 0.002) and age (p = 0.015) on structure, whereas the area was significantly influenced by sex (p = 0.005). Conclusion: Events of soft-tissue overuse injuries are the most common reasons resulting in orthopedic presentations of adolescent elite athletes. Mostly, the lower extremity and the spine are affected, while sex and age characteristics on affected area and structure must be considered. Therefore, prevention strategies addressing the injury-event profiles should already be implemented in early adolescence taking age, sex as well as injury entity into account. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 559 KW - overuse injuries KW - epidemiology KW - complaints KW - symptoms KW - risk factors KW - sports Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-434953 SN - 1866-8364 IS - 559 ER - TY - JOUR A1 - Cassel, Michael A1 - Müller, Juliane A1 - Moser, Othmar A1 - Strempler, Mares Elaine A1 - Reso, Judith A1 - Mayer, Frank T1 - Orthopedic Injury Profiles in Adolescent Elite Athletes BT - A Retrospective Analysis From a Sports Medicine Department JF - Frontiers in Physiology N2 - Aim: The aim of the study was to identify common orthopedic sports injury profiles in adolescent elite athletes with respect to age, sex, and anthropometrics. Methods: A retrospective data analysis of 718 orthopedic presentations among 381 adolescent elite athletes from 16 different sports to a sports medical department was performed. Recorded data of history and clinical examination included area, cause and structure of acute and overuse injuries. Injury-events were analyzed in the whole cohort and stratified by age (11–14/15–17 years) and sex. Group differences were tested by chi-squared-tests. Logistic regression analysis was applied examining the influence of factors age, sex, and body mass index (BMI) on the outcome variables area and structure (a = 0.05). Results: Higher proportions of injury-events were reported for females (60%) and athletes of the older age group (66%) than males and younger athletes. The most frequently injured area was the lower extremity (47%) followed by the spine (30.5%) and the upper extremity (12.5%). Acute injuries were mainly located at the lower extremity (74.5%), while overuse injuries were predominantly observed at the lower extremity (41%) as well as the spine (36.5%). Joints (34%), muscles (22%), and tendons (21.5%) were found to be the most often affected structures. The injured structures were different between the age groups (p = 0.022), with the older age group presenting three times more frequent with ligament pathology events (5.5%/2%) and less frequent with bony problems (11%/20.5%) than athletes of the younger age group. The injured area differed between the sexes (p = 0.005), with males having fewer spine injury-events (25.5%/34%) but more upper extremity injuries (18%/9%) than females. Regression analysis showed statistically significant influence for BMI (p = 0.002) and age (p = 0.015) on structure, whereas the area was significantly influenced by sex (p = 0.005). Conclusion: Events of soft-tissue overuse injuries are the most common reasons resulting in orthopedic presentations of adolescent elite athletes. Mostly, the lower extremity and the spine are affected, while sex and age characteristics on affected area and structure must be considered. Therefore, prevention strategies addressing the injury-event profiles should already be implemented in early adolescence taking age, sex as well as injury entity into account. KW - overuse injuries KW - epidemiology KW - complaints KW - symptoms KW - risk factors KW - sports Y1 - 2019 U6 - https://doi.org/10.3389/fphys.2019.00544 SN - 1664-042X VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Cassel, Michael A1 - Risch, Lucie A1 - Mayer, Frank A1 - Kaplick, Hannes A1 - Engel, Aaron A1 - Kulig, Kornelia A1 - Bashford, Greg T1 - Achilles tendon morphology assessed using image based spatial frequency analysis is altered among healthy elite adolescent athletes compared to recreationally active controls JF - Journal of science and medicine in sport : official journal of Sports Medicine Australia N2 - Objectives: Although expected, tendon adaptations in adolescent elite athletes have been underreported. Morphologically, adaptations may occur by an increase in collagen fiber density and/or organization. These characteristics can be captured using spatial frequency parameters extracted from ultrasound images. This study aims to compare Achilles tendon (AT) morphology among sports-specific cohorts of elite adolescent athletes and to compare these findings to recreationally active controls by use of spatial frequency analysis. Design: Cross-sectional observational study. Method: In total, 334 healthy adolescent athletes from four sport categories (ball, combat, endurance, explosive strength) and 35 healthy controls were included. Longitudinal ultrasound scans were performed at the AT insertion and midportion. Intra-tendinous-morphology was quantified by performing spatial frequency analysis assessing eight parameters at standardized ROls. Increased values in five parameters suggest a higher structural organization, and in two parameters higher fiber density. One parameter represents a quotient combining both organization and fiber density. Results: Among athletes, only ball sport athletes exhibited an increase in one summative parameter at pre-insertion site compared to athletes from other sport categories. When compared to athletes, controls had significantly higher values of four parameters at pre-insertion and three parameters at midportion site reflecting differences in both, fiber organization and density. Conclusions: Intra-tendinous-morphology was similar in all groups of adolescent athletes. Higher values found in non-athletes might suggest higher AT fiber density and organization. It is yet unclear whether the lesser structural organization in young athletes represents initial AT pathology, or a physiological adaptive response at the fiber cross-linking level. (C) 2019 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. KW - Tendon structure KW - Adaptation KW - Ultrasound KW - Athletic loading KW - Tendinopathy Y1 - 2019 U6 - https://doi.org/10.1016/j.jsams.2019.03.011 SN - 1440-2440 SN - 1878-1861 VL - 22 IS - 8 SP - 882 EP - 886 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Cassel, Michael A1 - Stoll, Josefine A1 - Schugardt, Monique A1 - Mayer, Frank T1 - Overuse and injury prevention JF - Elite youth cycling Y1 - 2019 SN - 978-1-315-11077-6 SN - 978-1-138-08684-5 SP - 141 EP - 159 PB - Routledge CY - London ER - TY - GEN A1 - Eichler, Sarah A1 - Salzwedel, Annett A1 - Rabe, Sophie A1 - Mueller, Steffen A1 - Mayer, Frank A1 - Wochatz, Monique A1 - Hadzic, Miralem A1 - John, Michael A1 - Wegscheider, Karl A1 - Völler, Heinz T1 - The Effectiveness of Telerehabilitation as a Supplement to Rehabilitation in Patients After Total Knee or Hip Replacement BT - Randomized Controlled Trial T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Background: Telerehabilitation can contribute to the maintenance of successful rehabilitation regardless of location and time. The aim of this study was to investigate a specific three-month interactive telerehabilitation routine regarding its effectiveness in assisting patients with physical functionality and with returning to work compared to typical aftercare. Objective: The aim of the study was to investigate a specific three-month interactive telerehabilitation with regard to effectiveness in functioning and return to work compared to usual aftercare. Methods: From August 2016 to December 2017, 111 patients (mean 54.9 years old; SD 6.8; 54.3% female) with hip or knee replacement were enrolled in the randomized controlled trial. At discharge from inpatient rehabilitation and after three months, their distance in the 6-minute walk test was assessed as the primary endpoint. Other functional parameters, including health related quality of life, pain, and time to return to work, were secondary endpoints. Results: Patients in the intervention group performed telerehabilitation for an average of 55.0 minutes (SD 9.2) per week. Adherence was high, at over 75%, until the 7th week of the three-month intervention phase. Almost all the patients and therapists used the communication options. Both the intervention group (average difference 88.3 m; SD 57.7; P=.95) and the control group (average difference 79.6 m; SD 48.7; P=.95) increased their distance in the 6-minute-walk-test. Improvements in other functional parameters, as well as in quality of life and pain, were achieved in both groups. The higher proportion of working patients in the intervention group (64.6%; P=.01) versus the control group (46.2%) is of note. Conclusions: The effect of the investigated telerehabilitation therapy in patients following knee or hip replacement was equivalent to the usual aftercare in terms of functional testing, quality of life, and pain. Since a significantly higher return-to-work rate could be achieved, this therapy might be a promising supplement to established aftercare. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 589 KW - telerehabilitation KW - home-based KW - total hip replacement KW - total knee replacement KW - exercise therapy KW - aftercare KW - rehabilitation Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-440965 SN - 1866-8364 IS - 589 ER - TY - JOUR A1 - Eichler, Sarah A1 - Salzwedel, Annett A1 - Rabe, Sophie A1 - Mueller, Steffen A1 - Mayer, Frank A1 - Wochatz, Monique A1 - Hadzic, Miralem A1 - John, Michael A1 - Wegscheider, Karl A1 - Völler, Heinz T1 - The Effectiveness of Telerehabilitation as a Supplement to Rehabilitation in Patients After Total Knee or Hip Replacement BT - Randomized Controlled Trial JF - JMIR Rehabilitation and Assistive Technologies N2 - Background: Telerehabilitation can contribute to the maintenance of successful rehabilitation regardless of location and time. The aim of this study was to investigate a specific three-month interactive telerehabilitation routine regarding its effectiveness in assisting patients with physical functionality and with returning to work compared to typical aftercare. Objective: The aim of the study was to investigate a specific three-month interactive telerehabilitation with regard to effectiveness in functioning and return to work compared to usual aftercare. Methods: From August 2016 to December 2017, 111 patients (mean 54.9 years old; SD 6.8; 54.3% female) with hip or knee replacement were enrolled in the randomized controlled trial. At discharge from inpatient rehabilitation and after three months, their distance in the 6-minute walk test was assessed as the primary endpoint. Other functional parameters, including health related quality of life, pain, and time to return to work, were secondary endpoints. Results: Patients in the intervention group performed telerehabilitation for an average of 55.0 minutes (SD 9.2) per week. Adherence was high, at over 75%, until the 7th week of the three-month intervention phase. Almost all the patients and therapists used the communication options. Both the intervention group (average difference 88.3 m; SD 57.7; P=.95) and the control group (average difference 79.6 m; SD 48.7; P=.95) increased their distance in the 6-minute-walk-test. Improvements in other functional parameters, as well as in quality of life and pain, were achieved in both groups. The higher proportion of working patients in the intervention group (64.6%; P=.01) versus the control group (46.2%) is of note. Conclusions: The effect of the investigated telerehabilitation therapy in patients following knee or hip replacement was equivalent to the usual aftercare in terms of functional testing, quality of life, and pain. Since a significantly higher return-to-work rate could be achieved, this therapy might be a promising supplement to established aftercare. KW - telerehabilitation KW - home-based KW - total hip replacement KW - total knee replacement KW - exercise therapy KW - aftercare KW - rehabilitation Y1 - 2019 U6 - https://doi.org/10.2196/14236 SN - 2369-2529 VL - 6 IS - 2 PB - jmir rehab CY - Toronto ER - TY - JOUR A1 - Khajooei, Mina A1 - Lin, Chiao-I A1 - Mayer, Frank A1 - Mueller, Steffen T1 - Muscle activity and strength in maximum isokinetic legpress testing with unstable footplates in active individuals JF - Isokinetics and exercise science : official journal of the European Isokinetic Society N2 - BACKGROUND: Compensating unstable situations is an important functional capability to maintain joint stability, to compensate perturbations and to prevent (re-)injury. Therefore, reduced maximum strength and altered neuromuscular activity are expected by inducing instability to load test situations. Possible effects are not clear for induced instability during maximum legpress tests in healthy individuals. OBJECTIVE: To compare isokinetic legpress (LP) strength and lower-leg muscle activity using stable (S) and unstable (UN) footplates. METHODS: 16 males (28 +/- 4 yrs, 179 +/- 7 cm, 75 +/- 8 kg) performed five maximum LP in concentric (CON) and eccentric (ECC) mode. The maximum force (Fmax) and muscle activity were measured under conditions of S and UN footplates. The tested muscles comprised of the tibialis anterior (TA), peroneus longus (PL) and soleus (SOL) and their activity were quantified against the MVIC of each muscle respectively. RESULTS: The main finding revealed a significant reduction in Fmax under UN condition: 11.9 +/- 11.3% in CON and 23.5 +/- 47.8% in ECC (P < 0.05). Significant findings were also noted regarding the RMS derived values of the EMG of PL and TA. CONCLUSION: Unstable LP reduced force generation and increased the activity of PL and TA muscles which confirmed greater neuromuscular effort to compensate instability. This may have some implications for resistance testing and training coupled with an unstable base in the prevention and rehabilitation of injury to the neuromusculoskeletal system. KW - Tibialis anterior KW - peroneus longus KW - soleus KW - instability Y1 - 2019 U6 - https://doi.org/10.3233/IES-182206 SN - 0959-3020 SN - 1878-5913 VL - 27 IS - 3 SP - 177 EP - 183 PB - IOS Press CY - Amsterdam ER - TY - GEN A1 - Mueller, Juliane A1 - Stoll, Josefine A1 - Mueller, Steffen A1 - Mayer, Frank T1 - Dose-response relationship of core-specific sensorimotor interventions in healthy, welltrained participants BT - study protocol for a (MiSpEx) randomized controlled trial T2 - Postprints der Universität Potsdam Humanwissenschaftliche Reihe N2 - Background: Core-specific sensorimotor exercises are proven to enhance neuromuscular activity of the trunk, improve athletic performance and prevent back pain. However, the dose-response relationship and, therefore, the dose required to improve trunk function is still under debate. The purpose of the present trial will be to compare four different intervention strategies of sensorimotor exercises that will result in improved trunk function. Methods/design: A single-blind, four-armed, randomized controlled trial with a 3-week (home-based) intervention phase and two measurement days pre and post intervention (M1/M2) is designed. Experimental procedures on both measurement days will include evaluation of maximum isokinetic and isometric trunk strength (extension/flexion, rotation) including perturbations, as well as neuromuscular trunk activity while performing strength testing. The primary outcome is trunk strength (peak torque). Neuromuscular activity (amplitude, latencies as a response to perturbation) serves as secondary outcome. The control group will perform a standardized exercise program of four sensorimotor exercises (three sets of 10 repetitions) in each of six training sessions (30 min duration) over 3 weeks. The intervention groups’ programs differ in the number of exercises, sets per exercise and, therefore, overall training amount (group I: six sessions, three exercises, two sets; group II: six sessions, two exercises, two sets; group III: six sessions, one exercise, three sets). The intervention programs of groups I, II and III include additional perturbations for all exercises to increase both the difficulty and the efficacy of the exercises performed. Statistical analysis will be performed after examining the underlying assumptions for parametric and non-parametric testing. Discussion: The results of the study will be clinically relevant, not only for researchers but also for (sports) therapists, physicians, coaches, athletes and the general population who have the aim of improving trunk function. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 499 KW - Sensorimotor training KW - Perturbation KW - Exercise KW - MiSpEx Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-422414 SN - 1866-8364 IS - 499 ER - TY - JOUR A1 - Plummer, Ashley A1 - Mugele, Hendrik A1 - Steffen, Kathrin A1 - Stoll, Josefine A1 - Mayer, Frank A1 - Müller, Juliane T1 - General versus sports-specific injury prevention programs in athletes BT - A systematic review on the effects on performance JF - PLoS ONE N2 - Introduction Injury prevention programs (IPPs) are an inherent part of training in recreational and professional sports. Providing performance-enhancing benefits in addition to injury prevention may help adjust coaches and athletes’ attitudes towards implementation of injury prevention into daily routine. Conventional thinking by players and coaches alike seems to suggest that IPPs need to be specific to one’s sport to allow for performance enhancement. The systematic literature review aims to firstly determine the IPPs nature of exercises and whether they are specific to the sport or based on general conditioning. Secondly, can they demonstrate whether general, sports-specific or even mixed IPPs improve key performance indicators with the aim to better facilitate long-term implementation of these programs? Methods PubMed and Web of Science were electronically searched throughout March 2018. The inclusion criteria were randomized control trials, publication dates between Jan 2006 and Feb 2018, athletes (11–45 years), injury prevention programs and included predefined performance measures that could be categorized into balance, power, strength, speed/agility and endurance. The methodological quality of included articles was assessed with the Cochrane Collaboration assessment tools. Results Of 6619 initial findings, 22 studies met the inclusion criteria. In addition, reference lists unearthed a further 6 studies, making a total of 28. Nine studies used sports specific IPPs, eleven general and eight mixed prevention strategies. Overall, general programs ranged from 29–57% in their effectiveness across performance outcomes. Mixed IPPs improved in 80% balance outcomes but only 20–44% in others. Sports-specific programs led to larger scale improvements in balance (66%), power (83%), strength (75%), and speed/agility (62%). Conclusion Sports-specific IPPs have the strongest influence on most performance indices based on the significant improvement versus control groups. Other factors such as intensity, technical execution and compliance should be accounted for in future investigations in addition to exercise modality. Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0221346 SN - 1932-6203 VL - 14 IS - 8 PB - PLOS 1 CY - San Francisco ER -