Is it possible to establish reference values for ankle muscle isokinetic strength? A meta-analytical study

BACKGROUND: The importance of measuring ankle muscle strength (AMS) has been demonstrated in a variety of clinical areas. Much data has been accumulated using the Cybex Norm isokinetic dynamometer but a uniform framework does not exist. OBJECTIVE: To identify pertinent studies which have used the Cybex Norm to measure AMS in order to establish reference values. METHODS: A narrative review of the literature was used to identify papers that have used the Cybex Norm to measure isokinetic concentric and eccentric AMS. RESULTS: Fifty five research papers were identified but each study used a different isokinetic protocol. CONCLUSIONS: It is not possible to produce AMS reference values due to the wide variation in data collection methods. This is therefore an area of research that needs further exploration

THE EFFECTS OF EXERCISE ON THE REHABILITATION OF KNEE LIGAMENT INJURIES IN ATHLETES

The purpose of the present study was to examine the effects of exercise on the rehabilitation of knee ligament injuries in athletes and to identify what the injured athletes consider as the most effective treatment concerning their rehabilitation, through the administration of a reported condition inquiry. Two hundred ninety six healthy subjects, 22,59+6,31 years old, participated in the research. All the subjects were active or former athletes, competed or had competed in athletic clubs throughout Greece, in various team sports or individual sports and competing categories and had suffered a knee ligament injury in their career as athletes. The effects of exercise on the rehabilitation of knee ligament injuries were measured through a scale of measurements. For data analysis was used the descriptive analysis of the SPSS version 20 for Windows. Data processing showed that the highest percentage of the knee injuries (43,80%) concerns anterior cruciate ligament (ACL) rupture, 34,40% partial or total meniscus rupture, 15,60% ligament injuries and 6,20% medial collateral ligament (MCL) or lateral collateral ligament (LCL) rupture. More than half of the knee injuries (53,10%), namely ruptures of ACL (76,50%), the partial-total rupture of meniscus (17,60%), and the patella dislocations and partial ruptures of MCL and LCL (5,90%), were treated surgically, combined with abstaining from training and matches, medication, bandage usage, immobilization with plaster-brace, medical examinations, physiotherapies, and special therapeutic exercise. The rest of the cases of the knee injuries (46,90%), namely all the cases of ligament over-voltages, ¾ of the meniscus ruptures, half of the patella dislocations and partial ruptures of MCL and LCL, as well as 1,25% of ACL rupture, were treated conservatively, with different combinations of  physiotherapies, special therapeutic exercises, abstention from training and games, medication, bandage usage, immobilization with plaster-brace, further medical examinations. In addition, almost all the injured athletes (except a 6,20%) did a combination of exercise modes for the rehabilitation of their knee ligament injury. More specifically, 18,80% did exercises with straps, resistance bands, weightbearing and isokinetic machine. In addition, 15,60% did exercises with straps, resistance bands, weightbearing, exercises in the water and isokinetic machine and the same percentage (15,60%) did exercises with straps, resistance bands, weightbearing and exercises in the water. 12,50% did exercises with resistance bands and weightbearing, 9,40% did exercises with resistance bands and in smaller percentages the athletes did exercises in the water and gaiting (6,20%), exercises with straps, resistance bands and weightbearing (6,20%), exercises with straps and resistance bands (3,10%), exercises with isokinetic machine and exercises in the water (3,10%), as well as exercises with resistance bands, exercises in the water and in the isokinetic machine (3,10%). In addition, 93,80% of the athletes stated that their knee ligament injury is completely or partially restored. Concerning the athletes’ opinions,  43,80% consider that the most effective treatment for the rehabilitation of their knee ligament injury was strengthening with weightbearing and resistance bands. Likewise, 35,30% of the athletes who underwent surgery consider strengthening mainly by weightbearing and resistance bands as the most effective treatment for the rehabilitation of their injury. In conclusion, according to the opinions of the athletes, who treated their knee ligament injury both non-operatively and operatively, the most effective treatment for the rehabilitation of the knee ligament injury was exercise in the mode of weightbearing and resistance bands. Thus, it could be said that exercise brings about significant positive effects on the rehabilitation of the knee ligament injury. Consequently, exercise should be an integral part of the knee ligament injury rehabilitation and prevention.   Article visualizations

The Relationship among Ankle Function, Functional Capacity, and Body Composition to Balance in Geriatric Populations

The primary purpose of this research study was to identify significant relationships among measures of ankle strength, ankle range of motion, body composition, and functional capacity to balance ability in geriatric populations which may potentially assist in identifying older individuals with increased risk of falling. A battery of five test (ankle strength assessments, ankle range of motion , DXA, functional fitness, and balance) were administered to 20 participants (6 males, 14 females, mean age 69.78 ± 3.98) that had indicated to be at least 65 years of age or older and no history of falls within the previous 12 months. Results demonstrated that no significant statistical relationships exist between functional components (R2 = .240, Part2 = .11, p = .358), relative strength (R2 = .240, Part2 = .09, p = .358), range of motion (R2 = .240, Part2 = .00, p = .358) and body composition (R2 = .240, Part2 = .07, p = .358) as each relates to balance. Additionally, the data failed to demonstrate any significant relationship of relative ankle strength (R2 = .19, Part2 = .08, p = .221) and ankle range of motion (R2 = .10, Part2 = .08, p = .221) as compared to functional capacity. Although the data failed to demonstrate statistical significance or strong correlations, the individual components effect on balance may be more appropriately observed when combined with more complex indicators of fall risk such as gait analysis or biomechanical measures in dynamic balance conditions

INFLUENCE OF ANKLE PASSIVE RANGE OF MOTION ON THE PERFORMANCE OF THE STAR EXCURSION BALANCE TEST

The purpose of this study was to measure the association between ankle passive range of motion (PROM) and the horizontal distance reached during the Star Excursion Balance Test (SEBT). Nineteen participants without any musculoskeletal and neurological injury performed the SEBT on eight directions proposed in the original protocol. The ankle PROM was measured with a manual goniometric device prior to the performance of the test. To determine the association between the distance reached during SEBT and the ankle PROM, we used the Pearson Correlation Coefficient Test (“r”). All directions of SEBT showed low correlation with the ankle PROM without significant differences for any variable. We concluded that the ankle PROM is not a confounding variable that should be monitored for use the SEBT for healthy individuals

HIP AND LUMBO-PELVIC STRENGTH IN SUBJECTS WITH PATELLOFEMORAL PAIN SYNDROME: A SYSTEMATIC REVIEW OF THE LITERATURE

The aim of this work was to: (i) review the current state of art about the strength of hip and lumbo-pelvic muscles in patients with Patellofemoral Pain Syndrome (PFPS), (ii) examine and (iii) establish considerations of the findings of the studies. Several databases were searched from 1980 to 2009 containing keywords related to PFPS and strength of Core muscles. After application of inclusion/exclusion criteria, 12 studies were selected in the literature search. The results suggest that most part of the studies found indicated that PFPS group showed a decreased ability to generate force, mainly by hip abductors, extensors and external rotators and trunk lateral flexors. These results point to a demand for training of these muscles during rehabilitation. None of these studies demonstrated a causal relationship between strength and appearance of PFPS

OBJECTIVE EVALUATION OF FUNCTIONAL ANKLE INSTABILITY AND BALANCE EXERCISE TREATMENT

Functional ankle instability (FAI) is a poorly defined entity but commonly used to describe patients who sustain multiple ankle injuries with slight or no external provocation and have a subjective feeling of ankle "giving way". There have been conflicting results reported in literature regarding the role of suggested etiological factors of FAI including deficit in joint proprioception, strength, and stiffness (laxity). Diagnosis of FAI has been mainly relied on a subjective reporting, so is the assessment of FAI treatments. In spite of controversies regarding FAI factors, balance training has been widely used in sports medicine clinics for patients with FAI. Most of past studies reported its effect for FAI, but strong evidence with definitive result is still missing. Furthermore, the mechanism that explains the effect of balance training on FAI is still unclear. Recently, it was suggested that altered threshold to the unloading reaction may be behind ankle giving way episodes in patients with ankle instability. Therefore, we wanted to duplicate this finding in individuals with FAI during sudden ankle inversion test and examine the effects of a four-week balance training program on unloading reactions in individuals with FAI. Twenty four recreationally active individuals with unilateral FAI were evaluated for unloading reactions on the involved and uninvolved limbs using a sudden ankle inversion test. In seven out of twenty-four subjects, we observed a drastic reaction (hyper-reactivity) in that they were unable to maintain upright standing position when a combination of dynamic ankle stretching and nociceptive stimuli was applied on their affected ankles. The subjects were then randomized to either a control or intervention group. Subjects in the intervention group were trained on the affected limb with static and dynamic components using a Biodex balance stability system for 4-weeks. The control group received no intervention. The results suggested that balance training may desensitize the hyper-reactivity to unloading reaction in FAI subjects, suggesting a possible mechanism for reducing the ankle "giving way" episodes. In addition, balance training was found to improve the subjective self-reported ankle instability and passive ankle joint position sense. No effect was observed on isometric and isokinetic peroneal muscle strength and ankle stiffness (laxity). In summary, this dissertation work provides evidence that balance training is effective in patients with FAI, however a further study with more sample size and additional outcome measures is required to better understand the mechanism of balance training in these individuals. The findings of this work have implications for research/rehabilitation of not only individuals with FAI but also in individuals with functional joint instability, such as functional knee instability which shares many common symptoms with FAI

New Trends in Neuromechanics and Motor Rehabilitation

Neuromechanics has been used to identify optimal rehabilitation protocols that successfully improve motor deficits in various populations, such as elderly people and individuals with neurological diseases (e.g., stroke, Parkinson’s disease, and essential tremor). By investigating structural and functional changes in the central and peripheral nervous systems based on neuromechanical theories and findings, we can expand our knowledge regarding underlying neurophysiological mechanisms and specific motor impairment patterns before and after therapies to further develop new training programs (e.g., non-invasive brain stimulation). Thus, the aim of this Special Issue is to present the main contributions of researchers and rehabilitation specialists in biomechanics, motor control, neurophysiology, neuroscience, and rehabilitation science. The current collection provides new neuromechanical approaches addressing theoretical, methodological, and practical topics for facilitating motor recovery progress

THE RELATIONSHIP BETWEEN MUSCULOSKELETAL STRENGTH, PHYSIOLOGICAL CHARACTERISTICS, AND KNEE KINESTHESIA FOLLOWING FATIGUING EXERCISE

Fatiguing exercise may result in impaired functional joint stability and increased risk of unintentional injury. While there are several musculoskeletal and physiological characteristics related to fatigue onset, their relationship with proprioceptive changes following fatigue has not been examined. The purpose of this study was to establish the relationship between musculoskeletal and physiological characteristics and changes in proprioception, measured by threshold to detect passive motion (TTDPM), following fatiguing exercise. Twenty, physically active females participated (age: 28.65 ± 5.6 years, height: 165.6 ± 4.3 cm, weight: 61.8 ± 8.0 kg, BMI: 22.5± 2.3 kg/m2, BF: 23.3 ± 5.4%). During Visit 1, subjects completed an exercise history and 24-hour dietary questionnaire, and body composition, TTDPM familiarization, isokinetic knee strength, and maximal oxygen uptake/lactate threshold assessments. During Visit 2, subjects completed TTDPM and isometric knee strength testing prior to and following a fatiguing exercise protocol. Wilcoxon signed rank tests determined TTDPM and isometric knee strength changes from pre- to post- fatigue. Spearman’s rho correlation coefficients determined the relationship between strength and physiological variables with pre- to post-fatigue changes in TTDPM and with pre-fatigue and post-fatigue TTDPM in extension and flexion (α=0.05). No significant differences were demonstrated from pre-fatigue to post-fatigue TTDPM despite a significant decrease in isometric knee flexion strength (P<0.01) and flexion/extension ratio (P<0.05) following fatigue. No significant correlations were observed between strength or physiological variables and changes in TTDPM from pre- to post-fatigue in extension or flexion. Flexion/extension ratio was significantly correlated with pre-fatigue TTDPM in extension (r=-0.231, P<0.05). Peak oxygen uptake was significantly correlated with pre-fatigue (r=-0.500, P<0.01) and post-fatigue (r=-0.520, P<0.05) TTDPM in extension. No significant relationships were demonstrated between musculoskeletal and physiological characteristics and changes in TTDPM following fatigue. The results suggest that highly trained individuals may have better proprioception, and that the high fitness level of subjects in this investigation may have contributed to absence of TTDPM deficits following fatigue despite reaching a high level of perceptual and physiological fatigue. Future studies should consider various subject populations, other musculoskeletal strength characteristics, and different modalities of proprioception to determine the most important contributions to proprioceptive changes following fatigue