Nikolaos Kofotolis

Ankle Sprain Injuries and Risk Factors in Amateur Soccer Players During a 2-Year Period

Background Although ankle sprains are common in soccer, the role of various risk factors in amateur soccer players is unclear. Purpose To identify the incidence of ankle sprain injuries, associated time loss of participation, and risk factors during two consecutive seasons in amateur players. Study Design Descriptive epidemiology study. Methods Of 336 athletes enrolled in the study, 312 male amateur soccer players were observed during a 2-year period. Ankle sprain injury incidents, participation time loss, injury mechanisms, ankle region injured, and other risk factors were recorded in games and practice sessions using questionnaires. Results During the study 208 ankle injuries were recorded, of which 139 were ankle sprains. These led to 975 sessions lost (on average, 7 lost sessions per injury). Most incidents (80.6%) were contact injuries, occurring mostly in defenders. Injury rates were equal between games and practice, while 61.1% of injuries were observed toward the end of each half of the game (P < .05). The injury incidence rate was higher during the first 2 months of the season as opposed to the last month (P < .05). Multinomial logistic regression showed that previous ankle sprain (P < .05) is a significant predictor of ankle sprain injury. Conclusion Ankle sprain injuries in amateur soccer players are primarily contact injuries, occurring mainly in defenders and during both games and practice. It appears that more injuries occur in players with previous ankle injury. Injury rates are higher toward the end of a game and chiefly occur during the first 2 months of the season.

Proprioceptive neuromuscular facilitation training induced alterations in muscle fibre type and cross sectional area

Objectives: To compare the effects of proprioceptive neuromuscular facilitation (PNF) and isokinetic training on fibre type distribution and cross sectional area of the vastus lateralis muscle. Methods: Twenty four male university students were divided into two equal groups: PNF training and isokinetic training (ISO). The training regimen for the PNF group consisted of three sets of 30 repetitions against maximal resistance, alternating two patterns of sequential movements of the right lower extremity: (a) toe flexion and ankle plantar flexion and eversion; (b) knee extension and hip extension, abduction, and internal rotation. The ISO group performed three sets of 30 repetitions alternating knee extension and flexion of the right leg at angular velocities of 180 and 90°/s in an isokinetic dynamometer (Cybex). Both groups trained three times a week for a total of eight weeks. Muscle biopsy specimens were obtained from the right vastus lateralis muscle before and after training. Results: The mean percentage area of type IIB fibre was significantly decreased (p<0.01) after eight weeks of PNF training, whereas that of type IIA fibre was significantly (p<0.05) increased. The mean percentage area of ISO trained type IIAB fibres exhibited an augmentative pattern (p<0.01) with a parallel reduction (p<0.05) in type IIA. Percentage fibre type distribution exhibited a similar pattern. Conclusions: Both PNF and ISO training alter fibre type distribution and mean cross sectional area. These changes occur in the type II fibre subgroup.

Synergetic and antagonist muscle strength and activity in women with knee osteoarthritis.

Background and Purpose:People with knee osteoarthritis (OA) display limitations in daily activities and a lower quality of life. The purpose of this study was to investigate the differences in strength balance and activation during maximum strength efforts between women with knee OA and asymptomatic women. Methods:Twelve women with knee OA (age 60.33 ± 6.66 years) and 11 controls (age 56.54 ± 5.46 years) performed maximum isokinetic eccentric and concentric knee extension and flexion tests at 60°/s, 120°/s, and 150°/s. Surface electromyography (EMG) was recorded from the biceps femoris (BF), vastus lateralis (VL), and vastus medialis (VM). Hamstrings-to-quadriceps moment ratios (H/Q), the synergetic (VL/VM), and co-contraction (BF/[VM + VL]) EMG ratios were calculated. Results:Analysis-of-variance designs showed that women experiencing knee OA had significantly higher H/Q moment ratios and VM/VL EMG ratios than controls (P < 0.05). The co-contraction index was significantly lower in the OA group only during knee flexion (P < 0.05). Conclusions:Women with knee OA showed a higher H/Q moment ratios probably because of the need for better joint stability or a lower quadriceps capacity. This deficiency was accompanied by a higher VM activation, which probably serves to stabilize the patella upon maximum contraction as well as a higher activation of antagonist muscles.

Reliability of Single-leg and Double-leg Balance Tests in Subjects with Anterior Cruciate Ligament Reconstruction and Controls

The purpose of this study was to assess the test–retest reliability of postural balance in patients with anterior cruciate ligament reconstruction (ACL) and controls. Ten healthy subjects and 15 individuals with ACL reconstruction performed single-leg and double-leg balance tests. The center of pressure (COP) was recorded using a pressure platform. For the total COP path, the intraclass correlation coefficient (ICC) ranged from 0.79 to 0.91. For the COP standard deviation, the ICCs ranged from 0.68 to 0.94. For the COP velocity, the ICCs ranged from 0.72 to 0.91. The sway area and ellipse scores displayed ICCs values of 0.67 to 0.95 and 0.53 to 0.92, respectively. The ICCs were higher for double leg tests compared with single-stance ones. These results indicate that 30 s balance tests in double and single-leg stance are reliable tools to assess static balance. The use of such tests to monitor rehabilitation programs following ACL reconstruction is recommended.

Effects of Pilates and trunk strengthening exercises on health-related quality of life in women with chronic low back pain

BACKGROUND Pilates programs are widely used as a form of regular exercise in a broad range of populations investigating their effectiveness for chronic low back pain (CLBP) treatment. OBJECTIVE The aim of this study was to compare the effects of a Pilates program and a trunk strengthening exercise program on functional disability and health-related quality of life (HRQOL) in women with nonspecific CLBP. METHODS A total of 101 volunteer women with CLBP provided data with a 3-month follow-up. They were randomized to either a Pilates (n= 37), trunk strengthening exercise (n= 36) or a control group (n= 28), exercising for a period of 8 weeks, three times a week. Data were collected on HRQOL using the Short-Form 36 Health Survey (SF-36v2), and functional disability using the Roland Morris Disability Questionnaire prior to program initiation, mid-intervention, immediately after program termination, and three months post-intervention. RESULTS The Pilates participants reported greater improvements on self-reported functional disability and HRQOL compared with participants in the trunk strengthening exercise and control groups (p < 0.05). The effects were retained for a period of three months after program termination for the Pilates group and to a lesser extent for the trunk strengthening exercise group. CONCLUSIONS An 8-week Pilates program improved HRQOL and reduced functional disability more than either a trunk strengthening exercise program or controls among women with CLBP.

Effects of instructional and motivational self-talk on balance performance in knee injured

Abstract Aims: To examine the influence of motivational and instructional self-talk on balance test performance of knee injured active individuals with meniscectomy. Design: One between-groups factor with four levels (instructional, motivational, no self-talk, neutral self-talk) and one within-groups “time” factor with two levels (pre-test, post-test). Method: 35 men and 25 women physically active and knee injured following meniscectomy 6 months ago participated. After 2 days of familiarization, they completed four dynamic balance stability trials, spaced 3 min apart. After the first two trials (best value as pre-test score), the participants were randomly assigned to four groups: the motivational self-talk group, instructional self-talk group and control groups (no instruction and neutral self-talk). They repeated the two trials (best value as post-test score) expressing aloud the phrases assigned. Results: Analysis of variance repeated-measures and Sidak multiple comparisons tests were performed on the time variable to detect differences in each group for each time point (pre- and post-test). Statistical analysis showed that balance board time score increased significantly only for experimental groups after the intervention period and not for control groups, F(3,56) = 9.93, p < 0.05, η2 = 0.861 for time of keeping stability on the board. Conclusions: The findings of the present study indicate that injured active individuals with meniscectomy may enhance their balance test performance via the use of instructional and motivational self-talk.

Neuromuscular interactions around the knee in children, adults and elderly

Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose of this study is to review recent evidence on age differences in neural activation and muscle balances around the knee when performing single joint movements. Particularly, current evidence indicates that there are some interesting similarities in the neuromuscular mechanisms by which children or the elderly differ compared with adults. Both children and elderly display a lower absolute muscle strength capacity than adults which cannot fully be explained by differences in muscle mass. Quadriceps activation failure is a common symptom of all knee injuries, irrespective of age but it is likely that its effect is more evident in children or adults. While one might expect that antagonist co-activation would differ between age categories, it appears that this is not the case. Although hamstring: quadriceps ratio levels are altered after knee injury, it is not clear whether this is an age specific response. Finally, evidence suggests that both children and the elderly display less stiffness of the quadriceps muscle-tendon unit than adults which affects their knee joint function.

Effects of Stabilization Exercises on Health-Related Quality of Life in Women With Chronic Low Back Pain

BACKGROUND The study examined the effects of a 4-week intensive isometric and isotonic stabilization exercise program on dimensions of health-related quality of life (HRQL) in women with chronic low back pain (CLBP). METHODS A total of 39 women (27-72 years old) provided data in an experimental study with a 9-month follow-up. Random allocation was undertaken for the two treatment groups out of the 3 groups: isometric stabilization (n = 13), isotonic stabilization (n = 13), and a control group (n = 13) that did not participate in any form of exercise. Health-related quality of life measures using the Short-Form 36 Health Survey were assessed before program initiation, immediately after program termination, and 4 times postintervention for a period of 9 months. RESULTS The isometric stabilization group displayed large improvements in bodily pain and vitality for women with CLBP attending a 4-week intensive isometric stabilization exercise program. The effects were retained for a period of 9 months after program termination. CONCLUSIONS Isometric stabilization exercises reduce pain and enhance vitality as dimensions of HRQL among women with chronic low back pain with such effects lasting for at least 9 months.

Health-Related Quality of Life in Children Attending Special and Typical Education Greek Schools

Abstract The purpose of this study was to examine parental perceptions about Health Related Quality of Life (HRQoL) of typical education and special education students in Greece. The Pediatric Quality of Life Inventory (PedsQL) was administered to the parents of 251 children from typical schools, 46 students attending integration classes (IC) within a typical school and 97 students attending special education (segregated) schools. A two-way analysis of covariance indicated that, compared to their typically developing peers, children attending special education schools and IC were reported by their parents to have lower PedsQL scores. Compared to children attending special education schools, children attending IC showed no differences in all PedsQL domains but the emotional domain score (p < .05). Based on parents’ responses, further improvements in special education settings and environments in the Greek educational system might be necessary to improve the HRQOL of students with disabilities.

Hamstring Elongation Quantified Using Ultrasonography During the Straight Leg Raise Test in Individuals With Low Back Pain

Although the straight leg raise (SLR) test frequently is used to assess hamstring extensibility in individuals with low back pain (LBP), evidence relating LBP, SLR, and hamstring extensibility remains unclear. The SLR measures the angle between the lifted leg and the horizontal, however, and, as such, it is not a direct measure of the elongation capacity of the hamstrings.