Isokinetic ankle muscle strength is reduced in recreational runners with medial tibial stress syndrome and is not associated with pain

Abstract Aim: The purpose of this study was to investigate the strength and ratios of the plantar flexors and ankle dorsiflexors in recreational runners with medial tibial stress syndrome and to assess the association between muscle strength and the level of pain in this population. Methods: Two groups (control and medial tibial stress syndrome) of eighteen runners each participated in this cross-sectional study. Isokinetic dynamometry was used to evaluate muscle strength, and for the analysis, the normalized isokinetic peak torque controlled by gender was used. Results: The medial tibial stress syndrome group showed lower normalized isokinetic peak torque in the dorsiflexors in the concentric (p = 0.008) eccentric (p = 0.011) contraction, as well as a lower plantar flexor, normalized isokinetic peak torque in the concentric (p = 0.001) and eccentric (p = 0.02) when compared to the control group. However, there was no difference in the normalized isokinetic peak torque ratio representative of the stance (p = 0.62) and swing phase (p = 0.16), and the level of pain was not correlated with the strength concentric (p = 0.32) and eccentric (p = 0.621) of plantar flexors, nor to the concentric (p = 0.21) and eccentric of dorsiflexors (p = 0.54). Conclusion: Recreational runners with MTSS showed decreased muscle strength in the sagittal plane of the ankle, no correlation with the level of pain, and no changing the ratio between plantar flexors and dorsiflexors.

Lesiones deportivas por sobreuso en niños y adolescentes / Sports injuries due to overuse in children and adolescents

La actividad deportiva en niños y adolescentes ha presentado un aumento sostenido en nuestro país en los últimos años; esto ha generado un aumento de las lesiones deportivas por sobreuso. Éstas pueden tener múltiples orígenes, dependiendo de la edad y la actividad del paciente. La mayoría son de manejo conservador, sin embargo, algunas requieren manejo quirúrgico. Lo más importante es la prevención de estas lesiones mediante el uso de equipo apropiado, regulando la intensidad y tipo de entrenamiento y tratando precozmente las lesiones.

Sports activity in children and adolescents has presented a sustained increase in our country in recent years, generating an increase in sports-related overuse injuries. These injuries vary in nature, depending on the patient ́s age and level of training. Most are conservatively managed; although, some will require surgical treatment. It is important, however, to try to prevent these injuries by using appropriate equipment, regulating the intensity and type of training and treating injuries early

Factores asociados a fractura por estrés: estudio de casos y controles en un centro médico de la marina de guerra de Perú / Factors associated with stress fracture: a case-control study in a Peruvian navy medical center

INTRODUCCIÓN: Las fracturas por estrés son lesiones producidas por el sobreuso de ciertas extremidades, generando fatigas repetitivas en el hueso con insuficientes periodos de descanso, trastornos hormonales, entre otras. Se produce una elevada actividad osteoclástica y una menor actividad de los osteoblastos a nivel cortical. OBJETIVO: Determinar los factores asociados a fractura por estrés en un centro médico de la Marina de Guerra de Perú. METODOLOGÍA: Se realizó una investigación de tipo observacional analítica de casos y controles. La variable dependiente fue la fractura por estrés, confirmada por resonancia magnética de los pacientes. Las variables independientes fueron edad, sexo y nivel de calcemia tomadas a partir de la historia clínica; el nivel socioeconómico y tiempo de actividad física diaria fueron datos recogidos mediante encuesta. Se obtuvieron los Odds ratio crudos y ajustados con un intervalo de confianza de 95%. RESULTADOS: Se trabajó con un total de 238 pacientes (119 casos y 119 controles), de los cuales 79,8% fueron varones y 20,2% fueron mujeres; la media de edad fue de 20,25 años. En el análisis bivariado se encontró asociación de fracturas por estrés con el sexo masculino (Odds ratio: 3,00; intervalo de confianza 95%: 1,51 a 5,95), hipocalcemia (Odds ratio: 2,83; intervalo de confianza 95%: 2,32 a 3,44), más de dos horas de actividad física diaria (Odds ratio: 24,74; intervalo de confianza 95%: 12,51 a 48,95) y un nivel socioeconómico C (Odds ratio: 6,66; intervalo de confianza 95%: 2,82 a 15,74). Mantuvieron su asociación en el análisis multivariado el tiempo de actividad física (Odds ratio: 44,46; intervalo de confianza 95%: 17,93 a 110,22) y el nivel socioeconómico C (Odds ratio: 22,57; intervalo de confianza 95%: 7,03 a 72,74). CONCLUSIÓN: Las fracturas por estrés estuvieron asociadas al tiempo de actividad física y a un nivel socioeconómico menor. Son necesarios más estudios para evaluar la relación con otros factores en la población militar de Perú.

INTRODUCTION: Stress fractures are injuries produced by the overuse of certain extremities, generating repetitive fatigue in the bone with insufficient rest periods and hormonal disorders, among others. High osteoclastic activity and lower activity of the osteoblasts at the cortical level occurs. OBJECTIVE: To determine the factors associated with a stress fracture in a single medical center of the Peruvian navy. METHODS: We conducted an observational, analytical case-control study. The dependent variable was stress fracture confirmed by magnetic resonance imaging of the patients; the independent variables were age, sex, calcemia, socioeconomic status, and time of daily physical activity. All data were extracted from the medical records. Crude and adjusted odds ratios were calculated with 95% confidence intervals. RESULTS: The sample was comprised of 238 patients (119 cases and 119 controls), of which 79.8% were male, and 20.2% were female; the average age was 20.25. In the bivariate analysis, stress fractures were associated with male sex (odds ratio 3.00; 95% confidence interval 1.51 to 5.95), hypocalcemia (2.83; 2.32 to 3.44), more than two hours of daily physical activity (24.7; 12.51 to 48.95) and socioeconomic level C (6.66; 2.82 to 15.74). Time dedicated to physical activity (adjusted odds ratio 44.46; 95% confidence interval 17.93 to 110.22) and socioeconomic level C (adjusted odds ratio 22.57; 95% confidence interval 7.03 to 72.74) were associated in the multivariate analysis. CONCLUSION: We found that stress fractures were associated with physical activity time and a lower socioeconomic level. Further studies are needed to evaluate the relationship with other factors in the military population of Peru.

Regulatory mechanism of the extracellular matrix during the development of bone-tendon junction overuse injury / 中国组织工程研究

BACKGROUND: Overuse tendinopathy is a common disease with no ideal treatment because the pathogenesis of tendinopathy is still unclear. OBJECTIVE: To explore the effects of enzymes affecting collagen synthesis on the metabolism of collagen I and collagen III during load accumulation in a model of patella-patellar tendon junction overuse injury. METHODS: Thirty-two adult female New Zealand white rabbits were randomly divided into a jumping group (n=16) and a control group (n=16). In the jump group, rabbits were subjected to jump training for 2, 4, 6, and 8 weeks, 150 jumps per day, 5 days per week. No intervention was performed in the control group. Bilateral patella-patellar tendon junction samples were taken at 24 hours after 2-, 4-, 6-, and 8- week training. The time-series changes of matrix metalloproteinase 1 (MMP1), tissue inhibitor of metalloproteinase 1 (TIMP1), collagen I, and collagen III were measured by immunohistochemistry. The study was performed with an ethic approval from the Animal Ethical Committee of Beijing Sport University, China (approval No. BSU2015022). RESULTS AND CONCLUSION: Compared with the control group, the MMP1 activity was significantly lower within the first 6 weeks of training, TIMP1 activity was significantly higher at 4-8 weeks of training, and TIMP1/MMP1 was significantly higher at 4-8 weeks of training. Compared with the control group, the expression of collagen I was significantly increased in the first 6 weeks of training, but the expression of collagen III was significantly lowered after 8 weeks of training. TIMP1 activity was significantly positively correlated with collagen I expression, and MMP1 activity was significantly negatively correlated with collagen I expression. To conclude, the patella-patellar tendon junction, during jumping load accumulation, mainly responded to load stimulation by increasing collagen I expression. In the first 2 weeks of load accumulation, the expression of collagen I was mainly increased by inhibiting MMP1 activity; in the period of 4 to 6 weeks of load accumulation, the expression of collagen I was mainly increased by increasing the activity of TIMP1 and inhibiting the activity of MMP1; and after 8 weeks of load accumulation, TIMP1 could promote collagen synthesis but with inability to antagonize the degradation of collagen I and III by MMP1. Then the expression of collagen I decreased from the peak level after 6 weeks of training to the control group level, and the level of collagen III decreased to be less than the level of the control group.

Overuse Capsuloligamentous Injury of the First Metatarsophalangeal Joint: A Case Report / 대한족부족관절학회지

Capsuloligamentous injury at the first metatarsophalangeal (MTP) joint is a common traumatic injury during physical activity, particularly on artificial turf. Mechanism of injury include excessive flexion, extension, or valgus stress. We report a non-operatively treated capsuloligamentous injury at the first MTP joint, which did not occur traumatically but developed by a stress-related mechanism in a collegiate rower.

Corredores: bases científicas para la elección de calzado y prevención de lesiones / Runners: scientific basis for the choice of footwear and injury prevention

El diseño de calzado deportivo para corredores aumenta en tecnología aplicada con el fin de disminuir las lesiones propias de este deporte como las tendinopatias y fascitis plantar. Existen múltiples opciones para conseguirlo, estas son principalmente los acolchados especiales en pacientes supinadores y las suelas con control de la pronación en hiperpronadores. Otros puntos en discusión son los materiales y su duración, el tipo y superficie de entrenamiento. Distintos trabajos asociaron el uso de varios calzados deportivos a la disminución de lesiones, pero aun no existe literatura sólida que avale con buen nivel de evidencia esta asociación. Siendo principalmente el mercado y la moda los responsables de su utilización. Resulta necesario aumentar aun más el conocimiento, desarrollo tecnológico y mejorar los estudios científicos actuales con el fin de poder ayudar a los corredores en la elección del calzado para su práctica deportiva.(zzAU)

Technologies applied to runner’s footwear design have increased over time in order to reduce specific-sport injuries such as Achilles tendinopathy and plantar fasciitis. Localized padding and controlled soles for pronators and supinator have shown good clinical results, respectively. There are still controversies in runner’s footwear design, such as, material selection and duration, training surface and type. Several studies have shown that the use of specific sport footwear reduces the incidence of these lesions. However there is lack of evidence type 1 or 2 to support these findings. Currently footwear selection is based according to fashion and market offers.

Influência das órteses plantares no ciclismo / Effects of foot ortheses on cycling Performance

A pronação excessiva da articulação subtalar é uma disfunção anatômica que provoca um desalinhamento do membro inferior alterando parâmetros biomecânicos (e. g. rotação medial da tíbia e joelho valgo). Esta disfunção contribui para o desenvolvimento de lesões por uso repetitivo no ciclismo. O objetivo desta revisão de literatura foi analisar a função e a prescrição de órteses para correção da pronação da articulação subtalar e antepé de ciclistas. Quarenta e nove textos, entre artigos científicos e livros, publicados de 1985 a 2011 foram analisados. Foi observado que não há estudos científicos suficientes para demonstrar a efetividade da prescrição do uso de órteses como medida preventiva de lesões por uso repetitivo decorrente da pronação excessiva da articulação subtalar em ciclistas.

The overpronation of subtalar joint is an anatomical dysfunction that results in misalignment of the lower limb by changing biomechanical parameters (e. g. tibial internal rotation, knee valgus). The misalignment contributes to the development of overuse injuries in cycling. The purpose of this reviewwas to evaluate the role and prescription of orthotics to correct overpronation of the subtalar joint and forefoot in cyclists. Forty-nine texts, including scientific articles and books, published from 1985 to 2011 were used. It was observed that there are not enough scientific studies to support the existing prescription of orthotics for injury prevention resulting from overpronation of the subtalar joint in cyclists.

Risk Factors of Past Injuries among of the Rowing Athletes Who Participated in the National Sports Festival / 대한스포츠의학회지

The purposes of this study were basic data collection and evaluation of the risk factors regarding rowing injuries through an epidemiologic study. We performed a questionnaire survey from rowers who participated in the 91th Annual Sports Festival in Jinju, Gyeongnam, in October 2010. 145 rowers (male: 84, female: 61) responded to the survey. The t-test was used for comparisons for the type of injury, age, and gender. The multiple linear regression analysis and the logistic regression analysis was used for the evaluation of risk factors. Overall, 100 (69.0%) rowers had a history of injury. The incidence of overuse injuries was significantly higher than the incidence of traumatic injuries (2.07+/-2.59/rower vs. 1.46+/-2.08/rower, p=0.027). The incidence of injuries for the adult group was significantly higher than those in the youth group (4.42+/-4.45/rower vs. 2.61+/-3.63/rower, p=0.008). There was no significant difference between males and females (3.85+/-4.33/rower vs. 3.08+/-3.87/rower, p=0.275). Also, the incidence of cross-training related injury was significantly higher in traumatic injuries rather than in overuse injuries (0.92+/-1.54/rower vs. 0.5+/-1.07/rower, p=0.008). In addition, rowing injuries were more related with overuse injuries. Risk factors regarding overall rowing injuries were training time, and training using stairs. Traumatic injuries were related with diverse cross-training and time spent cross-training. Therefore, in order to reduce the incidence of rowing injuries, time and the number of cross-training sessions should be reduced. Moreover, highly risky training such as using stairs should be replaced with other low risk training methods.

The value of three-phase bone scintigraphy in the assessment of stress fractures

Stress fractures are overuse injuries of the bones resulting from repetitive stresses. Since symptoms are non-specific, an imaging modality is mandatory for accurate diagnosis. Bone scintigraphy used to be the gold standard in evaluating stress fracture, but the advent of MRI led to its underutilization. This study aims to determine the role of three-phase bone scintigraphy in the assessment of stress fracture, and to determine the sensitivity, specificity, positive and negative predictive values and the accuracy rate of bone scan. In a tertiary hospital in Metro Manila, 15 patients referred for three-phase bone scintigraphy to assess for stress fracture from 2004 to 2006 were included in the study. Of these 15 patients, 12 also underwent MRI. Sensitivity, specificity, positive and negative predictive values, and the accuracy rate were computed with MRI as the gold standard. The sensitivity of bone scans approach 100 percent. However, its specificity is low due to other conditions that can produce a positive scan. Because of the limitations inherent to scintigraphy, MRI could be a valid first-line imaging technique in diagnosing stress fracture. MRI provides a greater anatomic detail of the area in question. It may secure an accurate diagnosis if the fracture line is demonstrated. However, extensive marrow edema precludes the visualization of the fracture line in some cases. Bone scintigraphy together with an accurate history is still a very useful tool in diagnosing stress fracture. MRI should be reserved for cases where the radiographic and scintigraphic findings are indeterminate.

In-line Skating Injuries and Rehabilitation

In-line skating is one of the fastest growing recreational sport activities all over the world, particularly in Korea. Fractures, dislocations, sprains and avulsions account for 60~70% of all acute injuries from in-line skating. The wrist area, including the wrist and the lower arm, is the most commonly injured site. To decrease the incidence and severity of acute injuries, the use of safety gears is critical. Also, overuse injuries can occur in the shoulder area, low back, knee, foot and ankle. Avoidance of overwork, rest, stretching and strengthening exercise, well-fit boots, and the proper skating posture can prevent or minimize the overuse injuries.

Clinical Manifestations of Overuse Injury in Musicians

OBJECTIVE: To know the clinical features of overuse injury in performing musicians and to evaluate related factors that may affect the overuse injury and playing related pain. METHODS: Eighty professional musicians and music college students were examined during 1 year. All were examined by a history taking, physical examination, radiologic exam and if needed electromyography. Nonparametric Sperman's correlation were used for the statistic analysis and 5 interval grading system, visual analog scale for pain, and stress, criteria of joint hypermobility were used for various measurements. RESULTS: Fifty four men were studied in 3 music colleges and a professional orchestra. Frequency of symptom was 46.3%. The string players were most frequently affected (65%), whereas the wind instrument players were least frequently affected (11.5%). The most commonly affected site was the hand and wrist (54.2%) followed by the spine. Patients were divided by the severity into 5 groups and among them the grade 1 was most common (29.6%). No significant correlation was seen between the practice hours per week but a significant correlation was noted between the stress and playing related pain. Joint hypermobility plays an important role in music playing which is dependent on the kind of instruments. CONCLUSION: Incidence of the overuse injury in musicians is high in Korea and the prevention and early treatment are essential for the good outcome of overuse syndrome.