Spyros I Athanasopoulos - Academia.edu (original) (raw)

Papers by Spyros I Athanasopoulos

American Journal of Physical Medicine & Rehabilitation, 1995

Dickstein R, Pillar T, Abulaffio N: Electromyographic activity of the biceps brachii muscles and ... more Dickstein R, Pillar T, Abulaffio N: Electromyographic activity of the biceps brachii muscles and elbow flexion during associated reactions in hemiparetic patients. Am J Phys Med Rehabil 1995;74:427—431 Activity of the biceps brachii muscles and movements of the elbows were studied during associated reactions in hemiparetic patients and in healthy volunteers. Onset time and increase in electromyographic (EMG) activity during associated reactions and onset of elbow flexion and its maximal magnitude were measured. Testing was performed while standing with a footswitch attached to the sole of the nonparetic foot in patients and to the sole of the right foot in controls. Lifting of that foot generated a trigger signal that served to time the dependent variables. Bilateral EMG activity associated with one foot stance appeared in the two upper extremities in both patients and controls. Elbow flexion occurred in the majority of patients bilaterally, whereas in controls it frequently took place on one side only. There was a significant difference between patients and controls in onset of EMG activity and elbow flexion. This difference indicates an earlier preparatory activity to one foot stance in the upper limbs of patients than in healthy controls. The greatest excursion into flexion was measured in the paretic upper extremity of patients; it significantly exceeded both the flexion angle measured in controls and increase in flexion angle on the nonparetic side. Further understanding of the nature of associated reactions seems to be required for their adequate treatment by physical procedures.

Knee pain and dysfunction have been often associated with an ineffective pull of the patella by t... more Knee pain and dysfunction have been often associated with an ineffective pull of the patella by the vastus medialis (VM) relative to the vastus lateralis (VL), particularly in individuals with knee joint malalignment. Such changes in muscular behavior may be attributed to muscle inhibition and/or atrophy that precedes the onset of symp-toms. The aim of this study was to investigate possible effects of knee joint malalignment, indicated by a high quadriceps (Q) angle (HQ angle 15°), on the anatomic cross-sectional area (aCSA) of the entire quadriceps and its individual parts, in a group of 17 young asymptomatic men compared with a group of 19 asymptomatic individuals with low Q angle (LQ angle 15°). The aCSA of the entire quadriceps (TQ), VM, VL, vastus intermedius (VI), rectus femoris (RF), and patellar tendon (PT) were measured during static and dynamic magnetic resonance imaging (MRI) with the quadriceps relaxed and under contraction, respectively. A statistically significant

The Foot, 2009

Excessive subtalar pronation causes significant changes in the biomechanics of the lower leg, adv... more Excessive subtalar pronation causes significant changes in the biomechanics of the lower leg, adversely influences proprioceptive feedback and neuromuscular reflex behavior and consequently, affects stability of the foot. However, the changes in muscle strength, caused by hyperpronation are unclear. The purpose of the present study was to compare the evertor and invertor peak torque between hyperpronated and normal individuals as well as between their dominant and non-dominant foot. 20 healthy male participants volunteered for this study. Leg dominance was assessed on the basis of a questionnaire and navicular drop measurements were used to classify participants into two groups: hyperpronated (&amp;gt; or =10 mm) and normals (5-9 mm). Isokinetic concentric eversion and inversion muscle group strength was tested at 30 degrees and 120 degrees/s using the Con-Trex MJ isokinetic dynamometer. In all cases, inversion peak torque was greater than eversion peak torque and declined with increasing angular velocity. No significant differences were found for inversion and eversion concentric strength at both speeds tested, neither between normal and hyperpronated individuals neither between their dominant and non-dominant foot. These results indicate the need re-evaluation of navicular drop values in order to identify normal and abnormal subtalar pronation. The assessment of eccentric contractions is also proposed when examining invertors and evertors isokinetic strength.

The Foot, 2005

Ankle bracing is widely used by sports participants in order to prevent lateral ankle sprains. Cu... more Ankle bracing is widely used by sports participants in order to prevent lateral ankle sprains. Current evidence on the various effects of ankle orthoses reveals that not only they are effective in minimizing the risk of injury, but also they do not hinder athletic performance and other parameters related to function. This review attempts to present all currently existing evidence regarding the effects of protective ankle braces and even more importantly, to discuss issues that have not been adequately investigated and identify areas for future research.

Surgical and Radiologic Anatomy, 2010

The purpose of the present study was to investigate whether an increased quadriceps angle (Q-angl... more The purpose of the present study was to investigate whether an increased quadriceps angle (Q-angle) has an effect on patellar positioning and/or the thickness of the medial and lateral tibiofemoral and patellofemoral articular cartilage and menisci, in a group of young asymptomatic individuals. These individuals were detected in a previous study with a decreased anatomical crosssectional area of the vastus medialis and lateralis as a result of an increased Q-angle. Patellar positioning and the thickness of the articular cartilages were determined in 19 asymptomatic male individuals with high Q-angle (HQ-angle) (18.5°± 2.6°) using magnetic resonance imaging (MRI). Seventeen male counterparts with low Q-angle (10.1°± 1.9°) were used for comparison. The position of the patella was determined by measuring the sulcus angle, the lateral patella tilt, the patella-lateral condyle index and the bisect offset (BSO) with the quadriceps relaxed. The BSO, was also measured with the quadriceps under maximum isometric voluntary contraction. The thickness of the articular cartilages of the lateral and medial femoral condyles, the tibial condyles, the patellar facets and the menisci were also measured. Our data revealed that healthy individuals with HQ-angle are unlikely to demonstrate any changes in the position of the patella and/or the thickness of the knee articular cartilages. The decreased anatomical area of the vastus medialis and an almost equally atrophied vastus lateralis, which was previously observed in this group of individuals may prevent in part the misalignment of the patella and early wear of the tibiofemoral and patellofemoral articular cartilages.

NeuroImage, 2006

Studies of unilateral finger movement in right-handed subjects have shown asymmetrical patterns o... more Studies of unilateral finger movement in right-handed subjects have shown asymmetrical patterns of activation in primary motor cortex and subcortical regions. In order to investigate the existence of an analogous pattern during lower limb joints movements, functional magnetic resonance imaging (fMRI) was used. Eighteen healthy, right leg dominant volunteers participated in a motor block design study, performing unilateral right and left repetitive knee, ankle and toes flexion/extension movements. Aiming to relate lower limb joints activation to the well-described patterns of finger movement, serial finger-to-thumb opposition was also assessed. All movements were auditory paced at 72 beats/min (1.2 Hz). Brain activation during movement of the nondominant joints was more bilateral than during the same movement performed with the dominant joints. Finger movement had a stronger lateralized pattern of activation in comparison with lower limb joints, implying a different functional specialization. Differences were also evident between the joints of the lower limb. Ankle and toes movements elicited the same extend of MR signal change in the majority of the examined brain regions, whereas knee joint movement was associated with a different pattern. Finally, lateralization index in primary sensorimotor cortex and basal ganglia was significantly affected by the main effect of dominance, whereas the lateralization index in cerebellum was significantly affected by the joint main effect, demonstrating a lateralization index increase from proximal to distal joints.

Journal of Medical Engineering & Technology, 2008

The aim of this study was to develop a new apparatus capable of accurately recording and analysin... more The aim of this study was to develop a new apparatus capable of accurately recording and analysing torque-time curve during isometric muscle contractions of the elbow flexors. A total of 25 (age 29.3 + 5.0 years) non-athlete male volunteers participated in this study. To establish the measurement precision of the new testing apparatus and to determine possible sources of error in the results, a series of tests was performed. Instrument validity was assessed by comparing each selected measure (lever arm angular position, torque and maximal isometric torque) to a criterion (external inclinometer, calibrated weights and isokinetic dynamometer, respectively), while trial-to-trial and day-today comparisons of measurements were made to estimate the reproducibility of the instrument. The statistical outcomes of validity tests demonstrated high agreement between measures and associated criteria (Pearson correlation coefficient's values 4.97). Trial-to-trial correlations for maximal isometric torque in different elbow angles showed excellent reproducibility, as values of intraclass correlation coefficient (ICC [2,1]) ranged from 0.889 to 0.971, with higher value in the middle angle (908). The value of ICC [2,1] (day-today) for maximal isometric torque in 90 degrees was 0.986 and the respective standard error of measurement (SEM) was 1.5 Nm. Our results indicate that the isometric evaluation of elbow flexor muscles with the new dynamometer is accurate and reproducible.

Journal of Bodywork and Movement Therapies, 2006

European Journal of Applied Physiology, 2005

It has been reported that exercise with eccentric contractions can induce damage and inflammation... more It has been reported that exercise with eccentric contractions can induce damage and inflammation in human muscle tissue, the severity of which depends on the duration and the intensity of exercise. Platelet activating factor (PAF) is a potent inflammatory mediator implicated in a series of pathophysiological conditions. We sought to investigate the relationship between PAF and eccentric exercise induced muscle damage. Thirteen healthy, recreationally active male subjects (27.5+/-3.78 year) performed 36 maximum voluntary eccentric contractions on a motorized muscle dynamometer using the elbow flexor muscles of the non-dominant arm. Venous blood samples were collected immediately before and after exercise at 2, 24, 48, 72 and 96 h. PAF was isolated, purified and determined by a platelet aggregation assay. Serum levels of creatine kinase (CK), lactate dehydrogenase (LDH), C-reactive protein (CRP) and complement C3 (C3), plasma level of fibrinogen and whole blood level of leukocytes (and their subsets) were determined. Established indicators of muscle damage as maximum isometric torque (MIT), range of motion (ROM), relaxed arm angle (RANG), flexed arm angle (FANG), arm circumference (CIRC) and muscle soreness were also measured at the same time points. PAF, leukocytes, CK and LDH were elevated after exercise, while other biochemical parameters such as CRP, C3 and fibrinogen were unchanged. We also observed an inverse association between PAF and MIT and ROM, as well as a positive association with other markers of muscle injury, i.e. CK, LDH, FANG and CIRC (all P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05). Our findings may imply a role for PAF in the mechanism of eccentric exercise induced muscle damage.

Cortex, 2007

Functional magnetic resonance imaging (fMRI) was used 1) to describe the pattern of whole brain a... more Functional magnetic resonance imaging (fMRI) was used 1) to describe the pattern of whole brain activity during motion of isolated joints of the lower limb, 2) to examine the somatotopic organization of lower limb joint representations in the primary sensorimotor cortex and the anterior lobe of the cerebellum and 3) to quantify the degree of overlap between these lower limb joint activations. Eighteen healthy, right leg dominant volunteers participated in a motor block-design study, performing repetitive knee, ankle and toes flexion/extension movements. In order to relate lower limb joints activation to the well-described patterns of finger movement, serial finger-to-thumb opposition was also assessed. All movements were auditory paced at 72 beats/min (1.2 Hz). Isolated lower limb joints movement activated a distributed sensorimotor network, including primary and non-primary sensorimotor areas. Although a large overlap was evident in primary sensorimotor cortex (SM1) and cerebellum representations of the three lower limb joints, a somatotopic arrangement was recognizable with reference to center of mass coordinates of each individual joint in the above areas. Detection of active brain regions during movement of the lower limb joints is feasible with fMRI although a carefully optimized methodology protocol is required.

British Journal of Sports Medicine, 2007

First, to document the injuries sustained during the 2004 Olympic Games in a sample of patients v... more First, to document the injuries sustained during the 2004 Olympic Games in a sample of patients visiting the physiotherapy department of the Olympic Village polyclinic. Second, to provide information and data about the physiotherapy services for planning future Olympics and other mass gatherings. Observational study. Olympic Village polyclinic. 457 patients aged 15-72 years visited the physiotherapy department from 30 July through 30 August. The department&amp;amp;amp;amp;amp;amp;amp;#39;s workload was at a peak during the last 15 days of the Olympic Games (periods B and C). The most common injuries were overuse injuries (47.3%). The most common pathology for physiotherapy attendance was myofascial pain/muscle spasm (32.5%), followed by tendinopathy (19.2%) and ligament sprain (18.7%). The most prevalent site of injury was the thigh (21%), followed by the knee (14.1%) and the lumbar spine (13.5%). Most injuries had symptoms of &amp;amp;amp;amp;amp;amp;amp;lt;7 days&amp;amp;amp;amp;amp;amp;amp;#39; duration. The geographical region with the greatest demand for physiotherapy services was Africa (40.6%). Most patients were athletes (74.8%), although team officials accounted for a considerable number (14%). The smallest national teams--especially those from developing countries--were more likely to take advantage of services, probably because the larger teams had their own medical and physiotherapy staff. The characteristics of patients, their sustained injuries and the subsequent treatment varied by the accreditation status of the patients. The physiotherapy department&amp;amp;amp;amp;amp;amp;amp;#39;s workload was dependent on the Olympic Games schedule.

The American Journal of Sports Medicine, 2009

Background The mechanoreceptors located in anterior cruciate ligament (ACL) constitute an afferen... more Background The mechanoreceptors located in anterior cruciate ligament (ACL) constitute an afferent source of information toward the central nervous system. It has been proposed that ACL deficiency causes a disturbance in neuromuscular control, affects central programs and consequently the motor response resulting in serious dysfunction of the injured limb. Purpose The objective of this study was to investigate whether chronic anterior cruciate ligament injury causes plastic changes in brain activation patterns. Study Design Case control study; Level of evidence, 3. Methods Seventeen right leg–dominant male participants with chronic anterior cruciate ligament deficiency and 18 matched healthy male participants with no special sport or habitual physical activity participated in this study. Patient selection criteria comprised a complete right unilateral anterior cruciate ligament rupture ≥6 months before testing. Brain activation was examined by using functional magnetic resonance ima...

Scandinavian Journal of Medicine & Science in Sports, 2007

The effect idiopatbc of aerobic .. scollosls e. . 0. training in girls with Athanasopoulos S. Pax... more The effect idiopatbc of aerobic .. scollosls e. . 0. training in girls with Athanasopoulos S. Paxinos T. Tsafantakis E. Zachariou K. Chatziconstantinou S. The effect of aerobic training in girls with idiopathic scoliosis.

Knee pain and dysfunction has been often associated with an ineffective pull of the patella by th... more Knee pain and dysfunction has been often associated with an ineffective pull of the patella by the vastus medialis relative to the lateralis, particularly in individuals with knee joint malalignment. Such changes in muscular behaviour may be attributed to muscle inhibition and/or atrophy that precede the onset of symptoms. The aim of this study was to investigate possible effects of knee joint malalignment, indicated by a high Q-angle (HQ-angle>15º), on the anatomical cross-sectional area (a-CSA) of the entire quadriceps and its individual parts, in a group of 17 young asymptomatic males compared to a group of 19 asymptomatic individuals with low Q-angle (LQ-angle <15º). The a-CSA of the entire quadriceps (TQ), vastus medialis (VM), vastus lateralis (VL), vastus intermedius (VI), rectus femoris (RF) and patellar tendon (PT) were measured during static and dynamic magnetic resonance imaging (MRI) with the quadriceps relaxed and under contraction, respectively. A statistically s...

… journal of sports …, 2002

The purpose of this study was to investigate the effects of aerobic training, strength training a... more The purpose of this study was to investigate the effects of aerobic training, strength training and their combination on joint range of motion of inactive older individuals. Thirty-two inactive older men (65 - 78 yr) were assigned to one of four groups (n = 8 per group): control (C), ...

Journal of Applied Physiology, 2008

Knee pain and dysfunction have been often associated with an ineffective pull of the patella by t... more Knee pain and dysfunction have been often associated with an ineffective pull of the patella by the vastus medialis (VM) relative to the vastus lateralis (VL), particularly in individuals with knee joint malalignment. Such changes in muscular behavior may be attributed to muscle inhibition and/or atrophy that precedes the onset of symptoms. The aim of this study was to investigate possible effects of knee joint malalignment, indicated by a high quadriceps (Q) angle (HQ angle >15°), on the anatomic cross-sectional area (aCSA) of the entire quadriceps and its individual parts, in a group of 17 young asymptomatic men compared with a group of 19 asymptomatic individuals with low Q angle (LQ angle <15°). The aCSA of the entire quadriceps (TQ), VM, VL, vastus intermedius (VI), rectus femoris (RF), and patellar tendon (PT) were measured during static and dynamic magnetic resonance imaging (MRI) with the quadriceps relaxed and under contraction, respectively. A statistically significa...

Inflammation and oxidative stress have been implicated in the mechanism of eccentric exercise-ind... more Inflammation and oxidative stress have been implicated in the mechanism of eccentric exercise-induced muscle injury. This study examined whether baseline serum levels of selenium (Se), a trace element that participates in both antioxidant and anti-inflammatory systems, affects the overall response to injury. Thirteen males performed 36 maximal eccentric actions with the elbow flexors of the non-dominant arm on a motorized dynamometer. Venous blood samples were collected immediately before and after exercise at 2, 24, 48, 72 and 96 hours. Established indicators of muscle damage such as maximum isometric torque (MIT), range of motion (ROM), relaxed arm angle (RANG), flexed arm angle (FANG), arm circumference (CIRC), muscle soreness and serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) were determined at the same time points. Baseline serum levels of Se were also measured. Complementary data regarding assessment of Se status were retrieved by the use of a semi-quantitative food frequency questionnaire. All measures changed significantly (p < 0.05) after exercise. The main finding of this study was that baseline Se serum levels were associated inversely with CK, LDH and FANG and positively with MIT and ROM (p < 0.05). These data suggest that beyond overt Se deficiency, suboptimal Se status possibly worsens muscle functional decrements subsequent to eccentric muscle contractions.

Gait & Posture, 2013

Kinematic studies have shown that experimentally-induced overpronation or oversupination of the s... more Kinematic studies have shown that experimentally-induced overpronation or oversupination of the subtalar joint may alter the position of the legs, hips and pelvis and consequently the trunk and upper limb. The purpose of the present study was to examine whether such foot deformity affects the activity of muscles that act on the trunk and upper limb. Twenty-eight healthy individuals (11 males and 17 females) 21.4±1.9 years of age without skeletal deformity, leg length discrepancy (LLD), overpronated or oversupinated feet or excessive lateral pelvic inclination volunteered for the study. Bilateral EMG recordings of the latissimus dorsi, pectoralis major and rectus abdominis were undertaken for 30-s with each subject in the relaxed standing position and at 5° and 10° bilateral or unilateral overpronation or oversupination of the foot on the dominant side using wooden wedge-shape blocks. The recorded EMG activity was normalised based on the EMG activity produced by the muscles under investigation during maximum isometric voluntary contraction. The findings of the present study revealed that neither bilateral nor unilateral overpronation/oversupination of the feet induced a significant alteration of the EMG activity of the latissimus dorsi, pectoralis major and rectus abdominis on either the dominant or non-dominant side. These findings suggest that in the absence of other major structural deformity bilateral or unilateral foot overpronation or oversupination does not affect the EMG activity of muscles that act on the trunk and upper limb in quiet standing.

British Journal of Sports Medicine, 2011

To identify the intrinsic risk factors of non-contact strains in the hamstrings and quadriceps mu... more To identify the intrinsic risk factors of non-contact strains in the hamstrings and quadriceps muscles of professional soccer players via a cohort prospective design. A total of 100 professional soccer players (aged 19.4-27.8 years) from four professional teams underwent a composite musculoskeletal assessment at preseason. Intrinsic risk factors included dichotomies of asymmetries in muscle strength, flexibility, proprioception, anthropometry and knee joint stability, and of previous injuries. Muscle strains were prospectively monitored during the subsequent season using questionnaires. The data were analysed via binary logistic regression. Thirty-eight percent of the players sustained one or more lower-extremity muscle strains. Sixteen (42.1 %) and seven (18.4 %) of them were clinically diagnosed as having non-contact muscle strains at their hamstrings and quadriceps, respectively. Players with eccentric hamstring strength asymmetries (OR=3.88; 95% CI 1.13 to 13.23), functional leg length asymmetries (OR=3.80; 95% CI 1.08 to 13.33) and no previous hamstrings injuries (OR=0.15; 95% CI 0.029 to 0.79) were at greater risk of sustaining a hamstring muscle strain. Players with eccentric strength (OR=5.01; 95% CI 0.92 to 27.14) and flexibility asymmetries (OR=4.98; 95% CI 0.78 to 31.80) in their quadriceps as well as heavier (OR=10.70; 95% CI 0.73 to 156.37) and shorter players (OR=0.08; 95% CI 0.00 to 1.35) were at greater risk of sustaining a strain in this muscle group. Professional soccer players with functional asymmetries possess a higher risk of sustaining hamstring strains. Previous injury seems not to constitute a risk factor. The systematic isokinetic evaluation of the lower extremities during the preseason period can provide therapists and trainers with valuable data regarding the predictive elements of non-contact hamstring strains in professional soccer players.

The Foot, 2005

Electromyographic peroneal reaction time measurements is a well established and reliable method o... more Electromyographic peroneal reaction time measurements is a well established and reliable method of assessing the dynamic defence mechanism of the ankle joint against ankle sprains. Ankle bracing has been proved to be an effective prophylactic measure against injury since it restricts joint ROM. However, its role in improving the dynamic defence mechanism of the ankle according to the skin-brace interface application pressure, is unclear. The aim of this study was to investigate the effect of different pressures of ankle brace application in the peroneus longus reaction time. Thirty-three young, male, uninjured, physical education students were measured under three conditions: (1) without brace, (2) with brace and 30 kPa application pressure and (3) with brace and 60 kPa application pressure, as measured by a pressure sensitive sensor. Peroneal reaction time was assessed with surface electromyography, during a sudden inversion stress test on a trapdoor. The results demonstrated significant differences between the control (no brace condition) and the two brace conditions, with a significant increase of the peroneal reaction time, with increasing ankle brace application pressures, more pronounced in the 60 kPa pressure. The findings of this study show that prophylactic ankle bracing when applied tightly, seems to have a detrimental effect in the dynamic defence mechanism of the ankle joint, since it delays the peroneous longus activation onset during a simulated ankle sprain. Whether different brace application pressures introduced in this study can affect the incidence of ankle sprains remains to be examined.

American Journal of Physical Medicine & Rehabilitation, 1995

The Foot, 2009

The Foot, 2005

Surgical and Radiologic Anatomy, 2010

NeuroImage, 2006

Journal of Medical Engineering & Technology, 2008

Journal of Bodywork and Movement Therapies, 2006

European Journal of Applied Physiology, 2005

Cortex, 2007

British Journal of Sports Medicine, 2007

The American Journal of Sports Medicine, 2009

Scandinavian Journal of Medicine & Science in Sports, 2007

… journal of sports …, 2002

Journal of Applied Physiology, 2008

Knee pain and dysfunction have been often associated with an ineffective pull of the patella by t... more Knee pain and dysfunction have been often associated with an ineffective pull of the patella by the vastus medialis (VM) relative to the vastus lateralis (VL), particularly in individuals with knee joint malalignment. Such changes in muscular behavior may be attributed to muscle inhibition and/or atrophy that precedes the onset of symptoms. The aim of this study was to investigate possible effects of knee joint malalignment, indicated by a high quadriceps (Q) angle (HQ angle >15°), on the anatomic cross-sectional area (aCSA) of the entire quadriceps and its individual parts, in a group of 17 young asymptomatic men compared with a group of 19 asymptomatic individuals with low Q angle (LQ angle <15°). The aCSA of the entire quadriceps (TQ), VM, VL, vastus intermedius (VI), rectus femoris (RF), and patellar tendon (PT) were measured during static and dynamic magnetic resonance imaging (MRI) with the quadriceps relaxed and under contraction, respectively. A statistically significa...

Gait & Posture, 2013

British Journal of Sports Medicine, 2011

The Foot, 2005