Auswirkungen des COVID-19-Lockdowns auf physische Leistungsparameter im professionellen Fußball

Hintergrund

Die staatlichen Maßnahmen zur Eindämmung des Coronavirus SARS-CoV‑2 im Jahr 2020 brachten den Trainings- und Wettkampfbetrieb im professionellen Fußball in vielen Ländern zum zeitweiligen Erliegen. In Folge des Lockdowns waren die Trainingsmöglichkeiten zumeist auf unspezifische heimbasierte Trainingsmethoden begrenzt. Es ist unklar, ob sich die fehlenden sportspezifischen Belastungsreize negativ auf die physische Leistungsfähigkeit der Fußballspielenden auswirkten.

Methodik

Im Rahmen eines narrativen Reviews wurde mittels einer selektiven Literaturrecherche in den Datenbanken PubMed, Google Scholar und BISp-Surf nach Studien gesucht, welche die Auswirkungen des Lockdowns auf physische Leistungsparameter bei erwachsenen professionellen Fußballspielenden untersuchten.

Ergebnisse

In die Übersichtsarbeit wurden sechs prospektive Längsschnittstudien eingeschlossen. In allen Studien kam während der Quarantäne ein heimbasiertes Ersatztraining zum Einsatz. Vier Studien verglichen die Leistungsfähigkeit der Fußballer/-innen mit Leistungsdaten aus vorherigen Spielzeiten. Zwei Studien ermittelten die Leistungsfähigkeit der Sportler/-innen unmittelbar vor und nach der Lockdownperiode.

Diskussion

Während die allgemeine Kraft- und Ausdauerleistung durch heimbasierte Ersatztrainingsprogramme erhalten werden kann, weisen die Studien darauf hin, dass sich die fehlenden spezifischen Belastungsreize vor allem negativ auf die Schnelligkeits- und Schnellkraftleistung der Fußballspielenden auswirken könnten. Bei Rückkehr in den regulären Trainingsbetrieb sollte daher auf eine progressive Belastungssteuerung insbesondere im Schnelligkeitstraining geachtet werden, um das Risiko für Verletzungen zu senken.

Neural therapy of an athlete's chronic plantar fasciitis: a case report and review of the literature

Background

The focus of this case report is on the role of inflammation as a contributor to pain in plantar fasciitis and its cure by the injection of local anesthetics.

Case presentation

This is a case report on a 24-year-old white man, a middle-distance runner, with chronic unilateral plantar fasciitis and perceived heel pain for almost 1.5 years. He was treated with neural therapy (that is, injection of < 1 ml procaine 1% which is a local anesthetic with strong anti-inflammatory properties) of the surgical scar and along the surgical puncture channel. The follow-up period from the time of first presentation until publication was 2.5 years. At admission, pain intensity (visual analog scale) in the affected leg was severe (10 cm, visual analog scale; range 0–10 cm) when walking and moderate (5 cm, visual analog scale) when standing. After the first session of injections he could stand pain-free and pain when walking was markedly reduced (− 90%). After the third session, he reported no pain in the affected leg and could return to sports at his former level (no difference in training load compared to non-injured state). There was no recurrence of inflammatory signs or heel pain despite intense athletics training up to the date of publication.

Conclusions

In prolonged cases of plantar fasciitis, inflammation is an important component in the development of persistent pain. The results of our case describe the effects of three neural therapy sessions that abolished inflammation and associated heel pain. Neural therapy might be an effective and time-efficient approach in the treatment of plantar fasciitis, enabling an early return to sports.

Effects of aerobic exercise on brain metabolism and grey matter volume in older adults: results of the randomised controlled SMART trial

There is mounting evidence that aerobic exercise has a positive effect on cognitive functions in older adults. To date, little is known about the neurometabolic and molecular mechanisms underlying this positive effect. The present study used magnetic resonance spectroscopy and quantitative MRI to systematically explore the effects of physical activity on human brain metabolism and grey matter (GM) volume in healthy aging. This is a randomised controlled assessor-blinded two-armed trial (n=53) to explore exercise-induced neuroprotective and metabolic effects on the brain in cognitively healthy older adults. Participants (age >65) were allocated to a 12-week individualised aerobic exercise programme intervention (n=29) or a 12-week waiting control group (n=24). The main outcomes were the change in cerebral metabolism and its association to brain-derived neurotrophic factor (BDNF) levels as well as changes in GM volume. We found that cerebral choline concentrations remained stable after 12 weeks of aerobic exercise in the intervention group, whereas they increased in the waiting control group. No effect of training was seen on cerebral N-acetyl-aspartate concentrations, nor on markers of neuronal energy reserve or BDNF levels. Further, we observed no change in cortical GM volume in response to aerobic exercise. The finding of stable choline concentrations in the intervention group over the 3 month period might indicate a neuroprotective effect of aerobic exercise. Choline might constitute a valid marker for an effect of aerobic exercise on cerebral metabolism in healthy aging.

Is remote stretching based on myofascial chains as effective as local exercise? A randomised-controlled trial

Lower limb stretching based on myofascial chains has been demonstrated to increase cervical range of motion (ROM) in the sagittal plane. It is, however, unknown whether such remote exercise is as effective as local stretching. To resolve this research deficit, 63 healthy participants (36 ± 13 years, ♂32) were randomly assigned to one of three groups: remote stretching of the lower limb (LLS), local stretching of the cervical spine (CSS) or inactive control (CON). Prior (M1), immediately post (M2) and 5 min following intervention (M3), maximal cervical ROM was assessed. Non-parametric data analysis (Kruskal-Wallis tests and adjusted post hoc Dunn tests) revealed significant differences between the disposed conditions. With one exception (cervical spine rotation after CSS at M2, P > .05), both LLS and CSS increased cervical ROM compared to the control group in all movement planes and at all measurements (P < .05). Between LLS and CSS, no statistical differences were found (P > .05). Lower limb stretching based on myofascial chains induces similar acute improvements in cervical ROM as local exercise. Therapists might consequently consider its use in programme design. However, as the attained effects do not seem to be direction-specific, further research is warranted in order to provide evidence-based recommendations.

Range of motion and cervical myofascial pain

Several studies investigating myofascial pain syndrome include assessments of range of motion (ROM) as a diagnostic criterion. However, the value of ROM in this context has not yet been evaluated in controlled clinical studies. We aimed to examine whether patients with myofascial pain syndrome display alterations of ROM when compared to healthy subjects. Twenty-two individuals (13 females, 9 males; aged 33.4 ± 13.9 yrs) afflicted with active myofascial trigger points in the upper trapezius muscle as well as 22 age and sex matched healthy controls were included. All subjects underwent an examination of maximal active cervical ROM in flexion/extension assessed by means of a 3D ultrasonic movement analysis system (30 Hz; Zebris CMS 70). In the patients group, pressure pain threshold (PPT) of the trigger points was determined using a pressure algometer. Maximum range of motion in the sagittal plane did not differ between individuals with MTrP (125.9 ± 23.2°, 95% CI: 116.2-135.6°) and asymptomatic subjects (128.2 ± 20.4°, 95% CI: 119.7-136.7°; p > .05). In patients, PPT (1.7 ± .6, 95% CI: 1.5-1.9) was not correlated with cervical mobility (r = -.13; p > .05). Based on these pilot data, range of motion in flexion/extension is not a valid criterion for the detection of myofascial trigger points. Additional research incorporating movement amplitudes in other anatomical planes and additional afflicted muscles should be conducted in order to further delineate the relative impact of MTrP on range of motion.

Appraising the methodological quality of cadaveric studies: validation of the QUACS scale

Although systematic reviews are conducted in the field of anatomical research, no instruments exist for the assessment of study quality. Thus, our objective was to develop a valid tool that reliably assesses the methodological quality of observational cadaveric studies. The QUACS scale (QUality Appraisal for Cadaveric Studies) was developed using an expert consensus process. It consists of a 13-item checklist addressing the design, conduct and report of cadaveric dissection studies. To evaluate inter-rater reliability, a blinded investigator obtained an initial pool of 120 observational cadaveric studies. Sixty-eight of them were selected randomly according to sample size calculations. Three independent researchers rated each publication by means of the QUACS scale. The reliability of the total score was estimated using the intraclass correlation coefficient (ICC). To assess agreement among individual items, margin-free kappa values were calculated. For construct validity, two experts (an anatomist and an experienced physician) categorized the quality of 15 randomly selected studies as 'excellent' (4 points), 'moderate to good' (3 points), poor to moderate' (2 points) or 'poor' (1 point). Kendall's tau rank correlation was used to compare the expert ratings with the scores on the QUACS scale. An evaluation of feasibility was carried out during the reliability analysis. All three raters recorded the duration of quality appraisal for each article. Means were used to describe average time exposure. The ICC for the total score was 0.87 (95% confidence interval: 0.82-0.92; P < 0.0001). For individual items, margin-free kappa values ranged between 0.56 and 0.96 with an agreement of 69-97% among the three raters. Kendall's tau B coefficient of the association between expert ratings and the results obtained with the QUACS scale was 0.69 (P < 0.01). Required rating time per article was 5.4 ± 1.6 min. The QUACS scale is highly reliable and exhibits strong construct validity. Thus, it can confidently be applied in assessing the methodological quality of observational dissection studies.

[Sporting loads to Spondylodesis of lumbar spine: The return-to-play process]

BACKGROUND

Return to play (RTP) and competition following spinal fusion is of particular importance for athletes. There is a lack of guidelines for decision making in RTP processes.

OBJECTIVE

The purpose of this work was to provide a systematic review of the criteria and time of return in the RTP decision process for adults undergoing lumbar spinal fusion.

METHODS

Two independent investigators searched MEDLINE using MeSH terms. Targeted outcomes were criteria for return to play decisions and total duration of the RTP process.

RESULTS

So far, no prospective randomized controlled trials on RTP after spinal fusion considering inclusion and exclusion criteria are available. Five of the included studies are based on original data. Most of the identified studies are narrative reviews and, thus, exhibit low evidence levels. In addition to the narrative reviews, one observational study, two expert opinion surveys and two model development studies were found.

CONCLUSION

Based on the literature research, a positive RTP decision can be made if the following criteria are fulfilled: (1) anatomical and functional healing is complete, (2) safety of the athlete and secondary subjects during training and competition is guaranteed, (3) sport-specific skills are regained, and (4) patient is psychosocially ready. The RTP process can often be successfully initiated 6 months after surgery; some patients however, will never manage the return to full-contact sports and/or sports with risk of collision.

Short-term effects of acupuncture and stretching on myofascial trigger point pain of the neck: a blinded, placebo-controlled RCT

OBJECTIVES

This trial aimed to evaluate the short-term effectiveness of acupuncture plus stretching to reduce pain and improve range of motion in patients afflicted by cervical myofascial pain syndrome.

DESIGN

Randomized, blinded, placebo-controlled crossover study.

INTERVENTION

Nineteen patients (11 females, eight males, 33 ± 14 years) with myofascial neck pain in randomized order received the following treatments with one week washout between: acupuncture, acupuncture plus stretching, and placebo laser acupuncture.

MAIN OUTCOME MEASURES

Mechanical pain threshold (MPT, measured with a pressure algometer) represented the primary outcome. Secondary outcomes were motion-related pain (Visual Analogue Scale, VAS) and cervical range of motion (ROM, recorded by means of an ultrasonic 3D movement analysis system). Outcomes were assessed immediately prior as well as 5, 15 and 30 min post treatment. Friedman tests with post hoc Bonferroni-Holm correction were applied to compare differences between treatments.

RESULTS

Both acupuncture as well as acupuncture plus stretching increased MPT by five, respectively, 11 percent post treatment. However, only acupuncture in combination with stretching was superior to placebo (p<0.05). There were no significant differences between interventions at 15 and 30 min post treatment. VAS did not differ between treatments at any measurement. Five minutes after application of acupuncture plus stretching, ROM was significantly increased in the frontal and the transversal plane compared to placebo (p<0.05).

CONCLUSIONS

The combination of acupuncture and stretching could represent a suitable treatment option to improve cervical movement behavior and reduce trigger point pain in the short-term. However, additional studies further discriminating the placebo effects are still warranted.

[Sedentary behaviour and health]

Exercise-related public health recommendations and research for increased fitness and health had long focused on vigorous exercise or the lack thereof. Recently scientific interest in possible effects of sedentary behaviour (SB) (sitting) independent of moderate-vigorous intensity exercise has been growing.We conducted a selective literature search in Pubmed and the Sedentary Research Database with the outcomes SB, risk factors, mortality and morbidity in adults. We included only reviews and systematic reviews.Observational studies suggest an association between SB and all-cause and cardiovascular, but not cancer mortality. SB also seems to be associated with diabetes and overweight/weight gain. Evidence for other diseases, such as cardiovascular diseases, hypertension, cancer, and mental diseases is limited also because of the heterogeneity and poor methodology of the -studies. Intervention studies found inconsistent evidence that SB is associated with detrimental effects on markers of cardiometabolic risk.The evidence on the detrimental effects of sedentary behaviour is decreasingly convincing with the endpoints of mortality, -morbidity, and markers of metabolic risk, in that order. Higher TV and screen time, but not total SB seems to be associated with higher all-cause and cardiovascular, but not cancer mortality. Further intervention studies are needed to establish -dose-response relationships and potentially protective effects of cardiorespiratory fitness and physical activity.

Validity of the six-minute walk test in cancer patients

The present study evaluated the validity of the six-minute walk test (6MWT) in cancer patients. 50 subjects (36 f, 14 m; 57.4±10.2 years; during (56%) or off (44%) cancer treatment) performed a 6MWT and a spiroergometry on a cycle ergo-meter (0+25 W, 3 min) to evaluate maximum exercise capacity (VO2peak). A subsample (n=30) completed a retest of the 6MWT within 2-7 days. Patients covered a distance of 594±81 m during 6MWT at an average intensity of 86.3±9.6% of HRmax and achieved a VO2peak of 21.2±4.86 ml · kg - 1 · min - 1 during cycle ergometry. The distance walked correlated significantly (p<0.001) with VO2peak (r=0.67) and perceived physical function (EORTC QLQ-C30 physical function subscale) (r=0.55). Concerning reliability the intraclass correlation coefficient was r=0.93 (95%CI: +0.86;+0.97; p<0.001) and the coefficient of variation 3%. During retest participants walked 3.1% (95%CI: +1.1; +5.2) farther and achieved a higher RPE (+1.0; 95%CI: +0.3;+1.8). Limits of agreement were between - 43.1 and 76.4 m. In cancer patients the 6MWT seems to be as valid and reliable as in healthy elderly, cardiac and pulmonary patients. Thus, it can be recommended for use in cancer patients.

Exercise effects on HRV in cancer patients

The present study evaluated the effects of physical exercise on heart rate variability (HRV) in cancer patients. 3 matched groups of each 15 tumour patients (60.4±8.9 years, 27 male, 18 female) were recruited: Physical exercise group 1 (acute treatment), Physical exercise group 2 (post treatment) and non-intervention group (acute treatment, no exercise). Exercise group patients received counselling for exercise and participated in a Nordic-Walking program. Short-term HRV-recordings, assessments of fatigue and quality of life (QoL) were performed prior to and 16 weeks after the exercise program initiation. MANCOVA revealed group × time differences in total power frequency domain of HRV and QoL (p<0.05). TP follow-up scores [logms(2)] differed significantly between non-intervention and intervention post treatment (2.0±0.5 vs. 2.6±0.5), but not between non-intervention and intervention during acute treatment. QoL follow-up scores differed significantly between non-intervention and intervention during acute treatment (47±15 vs. 64±18) and post treatment (47±15 vs. 69±19). Exercise enhances cardiac autonomic regulation of tumour patients during and after acute treatment. Because of the association of higher HRV-parameters and prolonged survival in cancer patients, improvement in autonomic control may be an important goal of exercise.

Acupuncture in children and adolescents with bronchial asthma: a randomised controlled study

OBJECTIVE

This randomised controlled trial evaluates the immediate effects of acupuncture as an add-on therapy in in-patient rehabilitation of children and adolescents with bronchial asthma.

PATIENTS AND METHODS

In a pre-post design, the severity of symptoms, lung function, illness-specific quality of life (Paediatric Asthma Quality of Life Questionnaire - PAQLQ) and general and asthma-specific level of anxiety (State-Trait Anxiety Inventory for Children - STAIC) were investigated in 46 acupuncture and 47 control patients. In addition to asthma sports, climate therapy and behavioural training, the intervention group received acupuncture treatment with a standardised needle pattern (12 × 30 min.).

RESULTS

With acupuncture, the peak expiratory flow variability differs significantly (p<0.01) from that of the control patients' group. Moreover, the acupuncture group differs significantly in their rehabilitation response at the time of discharge concerning perceived anxiety (STAIC-S). The lung function tests do not present differences between groups.

CONCLUSION

After additional acupuncture, amelioration of peak expiratory flow variability and anxiety can be shown, without any difference in objective lung function tests and quality of life between study groups. Further studies might evaluate the effects of acupuncture on childhood asthma in an outpatient setting.

[Health prevention for children and adolescents in competitive sports]

The promotion of sport talents in Germany is federally standardised. Apart from the training and management support, annual sports-medical investigations with standardised procedures are mandatory for athletes' health and safety. For the first time, this study evaluates the prevalence ratio of medical findings in Hessian top athletes. The data of all athletes presenting in one of the 27 licenced examination centres in Hesse during the period of investigation were evaluated for age, sex and sports discipline as well as medical findings and a trinomial classification of the sports-related health status. The completeness of this collection in the relevant period from November 2006 to October 2007 was assured by cross-checking the application charts of all related sports associations. Data of 1620 (m: 904, 14.8 +/- 2.5 years; w: 716, 14.3 +/- 2.6 years) of all 1713 athletes presenting during the evaluation period were used for analysis. Medical findings (e. g., resulting in follow-up evaluation or further consultations) were seen in 83.5 % of all athletes. A small group (3.6 %) was temporarily, and one single athlete was completely exempted from sports participation. These results underline (additionally to the preventive capability of sports-medical investigations) the need for an annual medical consultation of juvenile athletes. Further investigations should be extended to other districts and classes and might evaluate the direct and indirect costs of diseases.

Overground and walkway ambulation with unilateral hip osteoarthritis: comparison of step length asymmetries and reproducibility of treadmill mounted force plate readings

The purpose of this study was to analyze and compare the degree of step length asymmetry of patients with hip osteoarthritis during free walking and treadmill ambulation and to determine the reproducibility of treadmill based vertical ground reaction force parameters. Twelve subjects with monoarticular hip osteoarthritis undergoing total hip replacement surgery were assessed preoperatively. The assessed parameters were step length, maximal forces at heel strike and push off minimum force, force inclining and declining rate and relative stance time. The results indicated significant step length differences when comparing overground and treadmill ambulation. The extent of step length asymmetry did not have a consistent expression in different gait conditions. The study demonstrated sufficient intraday reliability for mean GRF measurements. While comparing data from treadmill and walkway locomotion of patients with osteoarthritis it should be taken into account that the amount of step length asymmetry is not identical. Patients with gait disabilities seem to have a somewhat lower level of repeatability and it appears that an increased number of practice or acclimatization trials are necessary.

Postural correction by osteoporosis orthosis (Osteo-med): a randomized, placebo-controlled trial

Currently available therapeutic options for the correction of osteoporotic posture changes are not effective. Rigid or semi-rigid orthoses are only applicable in the early phase after vertebral body fractures, and the knowledge about the efficacy of flexible spinal orthoses is limited. Therefore, the present study is aimed at investigating the efficacy of a flexible spinal orthosis without any stabilizing components in terms of posture improvement. Forty women aged (65.9 +/- 8.4 years) with a proven osteoporosis (DXA < or = -2.5) were randomized to receive either of three treatment regimens: (i) Orthosis (Thämert Osteomed) with paravertebral/lumbosacral air chamber pads (as commercially available); (ii) The same orthosis without air chamber pads; and (iii) Placebo body stocking. Measurements were performed with a 3D real-time ultrasound topometry system (Zebris(R) CMS 70). The posture correction was substantially and significantly more marked in the first group (38% of the maximally possible intentional erection) as compared to the second (21%) and third group (13%). The orthosis with air chamber pads causes a clinically meaningful trunk support in patients with osteoporotic posture changes. Since the device contains no rigid stabilizing elements, the change in posture is considered to be a result of muscle activation due to sensomotor stimulation by the air chamber pads.

[Sports medical aspects in cardiac risk stratification--heart rate variability and exercise capacity]

The present study investigates the association of the predicted CHD-risk (PROCAM) with the individual endurance capacity and heart rate variability (HRV) in a population-based sample of sedentary elderly. After stratification, in 57 men (48.1+/-9.5 yrs.) with an overall PROCAM-risk <10% (28.7+/-10.9 points) and 22 men (54.5+/-7.7 yrs.) with a coronary 10-year risk > or =10% (50.8+/-5.6 points) cycle ergometries and short-term HRV analysis of time (RRMEAN, SDNN, RMSSD) and frequency domain parameters (LF, HF, TP, LF/HF) were conducted. Additionally the autonomic stress index (SI) was calculated. Nonparametric tests were used for statistical correlation analysis (Spearman rho) and group comparisons (Mann-Whitney). For endurance capacity [W/kg] (r=-0.469, p<0.001), SDNN (r=-0.302, p<0.05), RMSSD (r= -0.311, p<0.05), LF (r=-0.325, p<0.05), HF (r= -0.311, p<0.05) and TP (r= -0.307, p<0.05) negative monotone correlations with the coronary score-risk were determined. Significant positive correlations were calculated for SI (r=0.476, p<0.001). Except for RRMEAN and LF/HF significant group differences (p<0.05) were computed for SDNN (30.0+/-20.0 vs 20.0+/-10.0 ms), RMSSD (22.2+/-18.3 vs 18.0+/-8.7 ms), LF (90.9+/-241.5 vs 41.35+/-81.1 ms(2)), HF (43.0+/-105.1 vs 18.0+/-27.0 ms(2)) and TP (189.0+/-457.1 vs 100.0+/-157.6 ms(2)). Significant differences (p<0.01) were evaluated for exercise capacity (2.4+/-0.5 vs 1.8+/-0.3 W/kg) and SI (90+/-183 vs 322+/-291). The results underline the predictive value of HRV analysis in risk stratification and outline the interrelation of a decreased exercise capacity and autonomic function with a raised individual 10-year cardiac risk. As an independent parameter of the vegetative regulatory state the stress index may contribute to an increased practical relevance of short-time HRV analysis.

Walking patterns of hip arthroplasty patients: some observations on the medio-lateral excursions of the trunk

PURPOSE

This study examined the angular gait kinematics of the trunk and the pelvis in the frontal plane and their amount of side-to-side asymmetry in patients after total hip replacement arthroplasty.

METHOD

The angular gait kinematics of 12 male hip arthroplasty patients (53-70 years) were compared to ten age-matched and ten young (24-35 years) male control subjects. Average step times and medio-lateral oscillation amplitudes of the pelvic and thoracic recordings were calculated for each step. Between successive steps the asymmetry ratio was computed and the mean angle around which the side-to-side oscillations occurred was compared to the angle in a symmetrical standing trial.

RESULTS

ANOVA indicated no significant side differences in relative step cycle durations. Patients and senior controls had significantly (p<0.01) less pelvis side-to-side displacements than the younger controls. No significant between-group differences could be detected for the average asymmetry ratio. However, during walking the patients showed a significantly (p<0.01) increased lateral thorax and pelvis deviation.

CONCLUSIONS

Hip replacement patients' thoracic and pelvic position is characterized by a lateral shift throughout the gait cycle, while left and right symmetry of angular movements amplitudes remain at about the same value of unimpaired subjects.

[EMG analysis of shoulder muscles during preventive and therapeutic exercise in the overhead athlete]

Strengthening of the rotator cuff muscles in functional positions is one of the important demands in the prevention and rehabilitation of overhead athletes. The purpose of this study was to evaluate the influence of a new shoulder bar (SBT 1000) on the myoelectric activity of the deltoid muscle. Subjects included 12 healthy overhead athletes (control group) and 9 overhead athletes with subacromial pain syndrome (test group). Both groups performed bilateral internal and external shoulder rotations against resistance from a pulley. The position of 90 degrees abduction and elbow flexion was passively supported with the SBT 1000 and had to be actively hold without the SBT 1000. The electromyographic activity of the three heads of the deltoid was determined using surface electrodes. Rectified mean EMG data were analysed by three factor repeated measures ANOVA (group x bodyside x condition). Significant differences (p < 0,05) occurred between the conditions with and without SBT 1000 in all three heads of the deltoid. The percentage of reduction of muscle activity with the SBT 1000 in the dominant arm was 33 %, 29 % and 17 % for the anterior, middle and posterior head. No significant differences could be shown between control and test group or between the dominant and nondominant arm. With the SBT 1000 rotational shoulder exercise can be performed in a functional position with reduced involvement of the deltoid, which could be beneficial in prevention and rehabilitation of overhead athletes.

Neuromuscular control of walking with chronic low-back pain

The reported association of low-back pain and musculoskeletal disorders contributed to the examination of the lumbar spine and hip extensor activation patterns in back pain sufferers during walking. Seventeen idiopathic low-back pain male subjects and 16 healthy volunteers participated in the study. Hip joint ROMs in the sagittal plane and neuromuscular activities of erector spinae [L3, T12], gluteus maximus and biceps femoris were recorded on one randomly selected body side in each group. Analysis using the Student's t-test revealed significant differences for hip joint range of motion, stride time and significantly earlier onsets of the lumbar spine and hip extensors of the back pain sufferers compared with the healthy controls. It is assumed, that low-back disorders are related to changes of the lumbar spine and hip extensor recruitment pattern.

[Gait disorders - assessment and rehabilitation supported by movement analysis]

AIM

The present paper validates the use of two-dimensional pelvis and thorax translation data for the assessment of gait disturbances and evaluates the effects of a real-time visual feedback system based on thoracic spine kinematics for gait rehabilitation.

METHODS

To validate the use of two-dimensional gait kinematics, vertical and horizontal displacements of pelvis (S1) and thorax (T12) markers of the twelve healthy individuals (25.9 +/- 2.7 years) were recorded during two gait perturbations: a brace constraining the knee to 30 degrees of flexure and a shoe lift of 3 cm. To investigate the effects of verbal instructions and additional real-time visual feedback on vertical and medial-lateral pelvis and trunk movements, gait kinematics were recorded during three randomized trials (verbal instruction, real-time visual kinematic feedback, free walking).

RESULTS

Gait deviations did result in significant (p < 0.05) increases of horizontal and vertical trunk pelvis movements. Significant (p < 0.05) reductions in oscillation amplitudes were noted when verbal cues and visual information were received. However, the major decrease occurred during real-time visual feedback.

CONCLUSION

Asymmetric limping, similar to gait disorders of individuals with hip pathologies, could be detected and described by two-dimensional thorax and pelvis translation data. It could be speculated that gait disorders may be addressed by real-time kinematic feedback training.

Comparison of angular lumbar spine and pelvis kinematics during treadmill and overground locomotion

OBJECTIVE

To determine the differences between angular oscillation curves of the lumbar spine and pelvis during walkway and treadmill ambulation.

DESIGN

An in vivo observation of walking in overground and treadmill conditions.

BACKGROUND

Angular movements of the lumbar spine and pelvis have been obtained during overground and treadmill walking. No data are available to indicate whether lumbar spine treadmill findings may be compared or generalized to overground readings.

METHODS

Nine male subjects walked at their natural cadence along an 8 m walkway positioned over a motorized treadmill. During each of 20 walking trials, kinematic data of one full gait cycle were collected in the middle segment of the walkway. Following the overground readings the walkway was removed and treadmill recordings were taken at the subjects' preferred walking speed and at an imposed speed of 1.25 m/s. Movement patterns and maximum oscillation angles were calculated in each plane.

RESULTS

Cross-correlation values of pairwise comparisons demonstrated almost comparable movement patterns between walking conditions (r > or =0.891; p<0.001) except for the movement in the sagittal plane (r=0.642, p<0.01). ANOVA for repeated measures revealed significant (p<0.05) differences in the gait cycle duration as well as reductions in oscillation amplitudes of the upper lumbar region and the pelvis in both the frontal and transverse plane during treadmill walking compared to walkway locomotion.

CONCLUSIONS

Statistically significant differences exist for some angular lumbar spine movement parameters between walkway and treadmill locomotion.

RELEVANCE

The observed differences between overground and treadmill locomotion should be taken in account when treadmill-based lumbar spine and pelvis kinematics want to be extended or compared to overground recordings.

Influences of nonspecific low back pain on three-dimensional lumbar spine kinematics in locomotion

STUDY DESIGN

A three-dimensional kinematic analysis of lumbar spinal movements with an ultrasonic measuring system was used to distinguish patients with chronic low back pain from those without such pain.

OBJECTIVES

To investigate the effects of chronic low back pain on the three-dimensional movements of the lumbar spine, and to identify variables that would allow discrimination among patients with chronic low back pain and control subjects.

SUMMARY OF BACKGROUND DATA

To the authors' knowledge, no previous studies have described or identified altered spinal and pelvic gait kinematics caused by nonspecific chronic low back pain in all anatomic planes.

METHODS

In this study, 34 participants with chronic low back pain and 22 subjects without such pain were monitored during treadmill gait. Data from the measuring system operating at 30 Hz were low-pass filtered and normalized to a percentage of the gait cycle.

RESULTS

Cross-correlations showed almost identical patterns of pelvic (S1) and thoracic (T12) movement curves in all anatomic planes between groups. No statistical group differences were detected for either pelvic or thoracic oscillation amplitudes. However, Student's t test showed significantly higher coefficients of variation (P < 0.01) in all anatomic planes of patients with chronic low back pain than in healthy control patients.

CONCLUSIONS

The phasic patterns and angular spinal displacements of patients with nonspecific low back pain were shown to be within normal limits. However, the patients demonstrated higher degrees of stride-to-stride variability, representing increased fluctuations in dynamic thoracic and pelvic oscillations. These findings, resulting in less than optimal gait patterns, must be considered in the rehabilitation of patients with chronic low back pain.

[Inline skating in school--perspectives from the sports medicine viewpoint]

INTRODUCTION

Children are motivated by new activities in physical education. Inline Skating (ILS) is one of the trend activities of the last years. For the establishment of ILS in school injury risks and the possible preventive transfer in leisure time activities are of interest. The aim of this study was to compare the incidence of injuries in an ILS-program in school with traditional activities of exercise lessons. Furthermore inline skate specific injury incidence in leisure time was evaluated.

METHOD

A sample of 47 schools was evaluated by a standardized questionnaire asking for: injury incidence in traditional sports and ILS and the incidence of ILS-injuries in leisure time.

RESULTS

The relative injury risk of ILS (% per 100 teaching units) is 14.3%. Basketball e.g. has an injury risk of 16.1%, handball 14.6%, gymnastics 13.9% and other games 9.5%. After the end of the ILS-program 37.3% of the students reported the incidence of an injury due to ILS in leisure time.

CONCLUSION

Compared to other activities in physical education ILS shows a moderate risk of injury and may improve the acceptance of active and passive prophylaxis.

[Sensomotor function while wearing lumbar support ortheses]

AIM

Flexible lumbar corsets should contribute to an improved active and passive stabilisation of the lumbar spine. In the present study, the effects of flexible corsets on sensory-motor abilities have been investigated.

METHODS

24 healthy subjects (m = 10, f = 14, 26.7 years) performed angle- and force-reproduction tasks with and without wearing a flexible corset. The subjects tried to reproduce trunk flexion angles of 20 degrees und 40 degrees as well as forces of 33% and 66% of the maximum strength of the back extensor muscles. Additionally, muscular reactions were measured during destabilizing stimuli.

RESULTS

No significant differences were found for the reproduction tasks. When wearing the corset, the left erector spinae muscles showed a delayed onset (+15 ms, p < 0.05), and the obliquus abdominis reached maximal activity more rapidly (-18 ms, p < 0.05). In the preinnervation phase the obliquus abdominis (-33%, p < 0.01), in the eccentric phase the erector spinae (-27%, p < 0.05) and the right obliquus abdominis (-46%, p < 0.05) and in the concentric phase the right obliquus abdominis (-35%, p < 0.01) and the rectus abdominis (-32%, p < 0.05) showed lower activities.

CONCLUSION

The reduced muscle activities with destabilizing stimuli can be interpreted as the result of an improved passive stabilisation of the lumbar region by wearing a flexible corset.

Lumbar corsets: their effect on three-dimensional kinematics of the pelvis

Lumbar corsets have been recommended for low back pain patients as a way of stabilizing the lumbar region, facilitating flexion movements, and reducing pain. However, little is known about how these devices affect lumbar motion. To determine the degree of changes in the lumbar region, our approach was to quantify three-dimensional kinematic data of the pelvis in harness-supported treadmill walking. Twelve healthy subjects (age=32+/-11.8 years) walked on a motorized treadmill at 4.5 km/h with and without wearing a lumbar corset. Three external markers overlying the sacrum were tracked by three ultrasound microphones, determining a local coordinate system, to obtain pelvic motions in the frontal, sagittal, and transverse planes. Raw kinematic data were low-pass filtered and normalized relative to the right heel strike. Mean values for net angular displacements of the pelvis were calculated for each plane within the 5th and 95th percentile. The Student's t-test demonstrated significant differences (P<0.001) between the corset/no-corset conditions in the frontal plane. An average 40% decrease in the relative pelvis up- and downward movement occurred in the frontal plane (4.1 degrees+/-2.9 degrees vs. 7.1 degrees+/-3.3 degrees). The analysis revealed no significant differences of net angular displacements in the sagittal (2.9 degrees+/-1.4 vs. 3.4 degrees+/-1.7 degrees) and the transverse planes (4.4 degrees+/-2.6 degrees vs. 4.3 degrees+/-2.1 degrees).