Ankle Plantarflexor Muscle Groups Research Articles

EFFECT OF FOOTBALL ON REHABILITATION OF ANKLE INJURY PATIENTS

ABSTRACT Introduction: Brief introduction: Ankle tendon and ligament sports injuries are common in football players. Objective: To continue to improve special strength training related to the characteristics of football after rehabilitation of injured ankle tendons and ligaments. Methods: Two master football sportsmen were rehabilitated by multi-point equal-length, short-arc and long-arc equal-speed training combined with balance ability exercises. Results: There were two long muscle L be maintain muscle tone plantar flexors force four times of 96 n/m, n/m 121, 140 n/m, 145 n/m than back flexors force of 63 n/m, 52 n/m, 60 n/m, 74 n/m tall. Plantar flexor fatigue was 57%, 30%, 29%, 12%, 28%, 18%, 20%, 21%. Conclusions: With the passing of time, the relative peak moment value of the right ankle plantar flexor muscle group of the two patients kept rising, the dorsiflexor muscle was basically flat, and the work fatigue index decreased step by step, indicating that the right ankle muscle strength level was significantly improved, the anti-fatigue ability was improved, and the rehabilitation treatment had a good effect. Level of evidence II; Therapeutic studies - investigation of treatment results.

Musculoskeletal modelling based estimates of load dependent relative muscular effort during resistance training exercises

ABSTRACT The purpose of this study was to investigate the relative muscular effort (RME) of the hip and knee extensor and ankle plantarflexor muscle groups during the back squat (BS) and split squat (SS) exercises across four external load conditions. Motion capture and force plate data were collected as participants performed the BS and SS at 0%, 25%, 50%, and 75% of their body-mass. These data were used to calculate net joint moments (NJM) at the hip, knee, and ankle of the front leg during the SS and the matched leg during the BS. A musculoskeletal model, which accounted for force-length-velocity properties of 52 muscles, was used to estimate the maximal possible NJM (NJMmax) of the hip and knee extensor and ankle plantarflexor muscle groups. RME was calculated as the ratio between NJM and NJMmax, and compared across exercises and loads. The results indicated that while hip extensor RME increased across all loads, the increases in hip extensor RME were disproportionately greater during the SS at loads of 50% and 75%. Knee extensor RME increased linearly across loads and did not differ between exercises. These results provide coaches and athletes with detailed information about how to optimise resistance training specificity.

Hind foot drumming: Volumetric micro-computed tomography investigation of the hind limb musculature of three African mole-rat species (Bathyergidae).

Several species of African mole-rats use seismic signalling by means of hind foot drumming for communication. The present study aimed to create three-dimensional reconstructions and compare volumetric measurements of 27muscles of the hind limb of two drumming (Georychus capensis and Bathyergus suillus) and one non-drumming (Cryptomys hottentotus natalensis) species of African mole-rats. Diffusible iodine contrast-enhanced micro-computed tomography (diceCT) scans were performed on six specimens per species. Manual segmentation of the scans using VGMAX Studio imaging software allowed for individual muscles to be separated while automatically determining the volume of each muscle. The volume of the individual muscles was expressed as a percentage of the total hind limb volume and statistically compared between species. Subsequently, three-dimensional reconstructions of these muscles were created. Musculus gracilis anticus had a significantly larger percentage of the total hind limb muscle volume in both drumming species compared to the non-drumming C. h. natalensis. Furthermore, several hip and knee extensors, namely mm. gluteus superficialis, semimembranosus, gluteofemoralis, rectus femoris and vastus lateralis, had significantly larger muscle volume percentages in the two drumming species (G. capensis and B. suillus) compared to the non-drumming species. While not statistically significant, G. capensis had larger muscle volume percentages in several key hip and knee extensors compared to B. suillus. Additionally, G capensis had the largest summed percentage of the total hind limb volume in the hip flexor, hip extensor, knee extensor and ankle plantar flexor muscle groups in all the three species. This could be indicative of whole muscle hypertrophy in these muscles due to fast eccentric contractions that occur during hind foot drumming. However, significantly larger muscle volume percentages were observed in the scratch digging B. suillus compared to the other two chisel tooth digging species. Moreover, while not statistically significant, B. suillus had larger muscle volume percentages in several hip extensor and knee flexor muscles compared to G. capensis (except for m. vastus lateralis). These differences could be due to the large relative size of this species but could also be influenced by the scratch digging strategy employed by B. suillus. Therefore, while the action of hind foot drumming seems to influence certain key muscle volumes, digging strategy and body size may also play a role.

A clinically applicable tool for rapidly estimating muscle volume using ultrasound images

PurposeThis study aimed to identify a safe, rapid, and accessible method of estimating muscle volume of key lower limb muscle groups to reduce the time-demand of acquiring this measurement and potentially facilitate its application as a clinical monitoring tool.MethodsUnilateral MRI images were acquired from the 12th thoracic vertebrae to the base of the foot in 18 recreationally active males. Panoramic B-mode ultrasound images were acquired from the same leg at the mid-hip, 25%, 50%, and 75% of thigh length, and 25% of shank length. Body mass, height, limb lengths, and circumferences at the sites corresponding to the ultrasound images were acquired. A single investigator manually analysed all images. Regression analyses were conducted to identify models for estimating volume of the hip extensor, knee extensor and flexor, and ankle plantarflexor muscle groups.ResultsModels were developed for estimating hip extensor (SEE = 8.92%, R2 = 0.690), knee extensor (SEE = 5.24%, R2 = 0.707) and flexor (SEE = 7.89%, R2 = 0.357), and ankle plantarflexor (SEE = 10.78%, R2 = 0.387) muscle group volumes. The hip and knee extensor models showed good potential for generalisation. Systematic error was observed for the knee flexor and ankle plantarflexor models.ConclusionsHip extensor, knee extensor and flexor, and ankle plantarflexor muscle group volumes can be estimated using B-mode ultrasound images and anthropometric measurements. The error shown for each of the models was sufficient to identify previously reported differences in muscle volume due to training or injury, supporting their clinical application.

COMPARISON OF EFFECT OF BALANCE DISC AND BOSU BALL ON ANKLE DORSIFLEXOR AND PLANTARFLEXOR MUSCLE STRENGTH

Purpose of this study is to compare effect of balance disc (duradisk, dynadisk, balance ball, inflatable disc, etc.) and bosu ball on the strength development of ankle dorsiflexor and plantarflexor muscles of sedentary children. 74 sedentary children with a mean age of 9.71 years (sd =0,370) were granted permission from their parents in accordance with the Helsinki Declaration. In the study, a balance disk group and a bosu group were formed by random sampling. Balance disk group with the balance disk to the bosu group with bosu balls, three days a week, the same training program was applied for 8 weeks. The pre and post test ankle strength measurements of all groups were measured using the ’Lafayette’ digital hand dynamometer and the differences between the groups were examined. The participants were asked to perform a right-left foot dorsiflexion, and right-left foot plantarflexion force measurements were performed for 5 seconds. Each measurement is repeated twice and the best result was recorded. Two-way analysis of variance was used for parametric results and Kruskall Wallis test for non-parametric results. Before the study, it was seen that there was no significant difference between the groups in the measurements (p>.05). Therefore, gender difference is not considered. After the research, both groups showed improvement according to the pre-tests. There was a significant difference between the balance disk group and the bosu group in favor of the balance disk group (p <.05). In our study, it was found that the training performed with balance disk and bosu ball significantly improved the strength of both ankle dorsiflexor muscle groups and ankle plantarflexor muscle groups. This result shows that the exercises with balance disc and bosu can increase the strength development of dorsiflexor and plantarflexor muscle groups in sedentary children. Therefore, it may be suggested that training with balance disc and bosu can be used as an alternative method for strength development for these muscle groups. Article visualizations:

Effects of a Fall Prevention Exercise Program on Muscle Strength and Balance of the Old-old Elderly.

[Purpose] The purpose of this study was to investigate the effects of an 8-week balance exercise and elastic-resistance exercise program on muscle strength and balance of the old-old elderly (over the age of 75). [Subjects and Methods] Fifty-five elderly persons were recruited from the community and assigned to three groups for convenience: balance exercise (intervention group 1; INT 1), resistance exercise (intervention group 2; INT 2), and control (CON) groups. The intervention was performed twice a week at a senior center and three times a week at home for 8 weeks. Muscle strength and balance were evaluated before and at the end of the trial, using a PowertrackIIand Tetrax. [Results] There were significant improvements in the strength of all seven muscle groups and balance in the INT 2 group. In the INT 1 group, there were significant improvements in the strength of all muscle groups except for the knee flexor and ankle plantar flexor muscle groups. [Conclusion] This study demonstrated that an intervention using balance exercises or elastic-resistance exercises is effective at improving the muscle strength and balance of the old-old elderly. These type of exercises should be appropriate for the physical characteristics of the subjects.

Overexpression of insulin‐like growth factor‐1 attenuates skeletal muscle damage and accelerates muscle regeneration and functional recovery after disuse

Skeletal muscle is a highly dynamic tissue that responds to endogenous and external stimuli, including alterations in mechanical loading and growth factors. In particular, the antigravity soleus muscle experiences significant muscle atrophy during disuse and extensive muscle damage upon reloading. Given that insulin-like growth factor-1 (IGF-1) has been implicated as a central regulator of muscle repair and modulation of muscle size, we examined the effect of virally mediated overexpression of IGF-1 on the soleus muscle following hindlimb cast immobilization and upon reloading. Recombinant IGF-1 cDNA virus was injected into one of the posterior hindlimbs of the mice, while the contralateral limb was injected with saline (control). At 20 weeks of age, both hindlimbs were immobilized for 2 weeks to induce muscle atrophy in the soleus and ankle plantarflexor muscle group. Subsequently, the mice were allowed to reambulate, and muscle damage and recovery were monitored over a period of 2-21 days. The primary finding of this study was that IGF-1 overexpression attenuated reloading-induced muscle damage in the soleus muscle, and accelerated muscle regeneration and force recovery. Muscle T2 assessed by magnetic resonance imaging, a non-specific marker of muscle damage, was significantly lower in IGF-1-injected compared with contralateral soleus muscles at 2 and 5 days reambulation (P<0.05). The reduced prevalence of muscle damage in IGF-1-injected soleus muscles was confirmed on histology, with a lower fractional area of abnormal muscle tissue in IGF-1-injected muscles at 2 days reambulation (33.2±3.3 versus 54.1±3.6%, P<0.05). Evidence of the effect of IGF-1 on muscle regeneration included timely increases in the number of central nuclei (21% at 5 days reambulation), paired-box transcription factor 7 (36% at 5 days), embryonic myosin (37% at 10 days) and elevated MyoD mRNA (7-fold at 2 days) in IGF-1-injected limbs (P<0.05). These findings demonstrate a potential role of IGF-1 in protecting unloaded skeletal muscles from damage and accelerating muscle repair and regeneration.

Factors Associated with the Timed Up and Go Test Score in Elderly Women

[Purpose] The purpose of this study was to determine the relationship between the Timed Up and Go (TUG) test score and the physical performance of women aged 75 years and over according to orthopedic status. [Subjects] The participants were 832 elderly women (mean age, 78.6 ± 2.7 years) who carried out their daily activities independently in their own homes and did not have histories of stroke or osteoarthritis of the hip. [Methods] Maximal voluntary contractions of the knee extensor and ankle plantar flexor muscle groups were measured using a hand-held dynamometer. One-leg standing time and usual walking speed were assessed as balance and walking performances. [Results] The TUG score was more strongly correlated with walking speed (r = -0.776) than the other measures of physical performance (r = -0.228 to -0.399). Correlations between the TUG score and walking speed were strongest for participants with knee osteoarthritis (r = -0.824) and fractures after 60 years of age (r = -0.809). A linear regression model of data from all participants showed that all performance scores and age were determinants of the TUG score (R2 = 0.634). The determinants of the TUG score for participants with osteoarthritis or fractures were walking speed and one-leg standing score, and age (R2 = 0.701) and walking speed, age, and knee strength (R2 = 0.688). Beta estimates of walking speed for all participants and for the subgroups were higher (-0.69 to -0.76) than those for the other determinants (-0.06 to 0.14). [Conclusion] Walking speed is a stronger determinant of the TUG score than muscle strength or balance for elderly women.

Lower extremity skeletal muscle function in persons with incomplete spinal cord injury

A cross-sectional study design. To characterize and specifically quantify impairments in muscle function after chronic incomplete spinal cord injury (SCI). University of Florida, Gainesville, FL, USA. Voluntary and electrically elicited contractile measurements were performed and voluntary activation deficits were quantitatively determined in the knee extensor and ankle plantar flexor muscle groups in 10 individuals with chronic incomplete SCI (C5-T8, ASIA C or D) and age-, gender-, height- and body weight matched healthy controls. Persons with incomplete-SCI were able to produce only 36 and 24% of the knee extensor torque and 38 and 26% of the plantar flexor torque generated by noninjured controls in the self-reported less-involved and more-involved limbs, respectively (P<0.05). In addition, both indices of explosive or instantaneous muscle strength, torque200 (absolute torque reached at 200 ms) and the average rate of torque development (ARTD) were dramatically reduced in the ankle plantar flexor and knee extensor muscle groups in persons with incomplete-SCI. However, the deficit in instantaneous muscle strength was most pronounced in the ankle plantar flexor muscles, with an 11.7-fold difference between the torque200 measured in the self-reported more involved limb and a 5-fold difference in the less-involved limb compared to control muscles. Voluntary activation deficits ranged between 42 and 66% in both muscle groups. Interestingly, electrically elicited contractile properties did not differ between the groups. The resultant impact of incomplete-SCI is that affected muscles not only become weak, but slow to develop voluntary torque. We speculate that the large deficit in torque200 and ARTD in the ankle plantar flexors muscles of persons with incomplete-SCI may limit locomotor function. The results presented in this study provide a quantitative and sensitive assessment of muscle function upon which future research examining rehabilitation programs aimed at restoring muscle function and promoting functional recovery after incomplete-SCI may be based.

Frontal plane knee angle affects dynamic postural control strategy during unilateral stance.

Center of plantar pressure (COPP) location moves toward the forefoot as ankle plantar flexor muscles attempt to maintain postural control during single leg stance. This study evaluated relationships between frontal plane tibiofemoral joint angulation during relaxed bilateral stance and mean COPP locations during vision-denied single leg stance at 20 degrees knee flexion. Fifty-six nonimpaired athletes (29 female, 27 male) were evaluated for frontal plane tibiofemoral joint angulation and standing foot angle by using two-dimensional videography (30 Hz). Mean anterior-posterior and mediolateral COPP locations were assessed during single leg stance on a mat (25 Hz, 15 s). One-way ANOVA and Tukey HSD tests evaluated group differences (P < or = 0.05) based on frontal plane tibiofemoral joint angulation. Group 1 (genu varus or genu valgus < 5 degrees ) displayed a mean anterior-posterior COPP location of 54.2 +/- 6% from the (0,0) coordinate starting point at the anterolateral foot (10.3 +/- 2 cm from the posterior sensor edge). Group 2 (genu varus angulation > or = 5 degrees ) and group 3 subjects (genu valgus angulation > or = 5 degrees ) displayed mean anterior-posterior COPP locations of 60.6 +/- 8% and 60.7 +/- 7% (8.8 +/- 2 cm and 8.7 +/- 2 cm from the posterior sensor edges), respectively. Group 2 (12.5 +/- 3 N x kg(-1)) and group 3 (12.4 +/- 3.1 N x kg(-1)) subjects also displayed greater mean plantar force magnitude/body weight than group 1 (10.3 +/- 2 N x kg(-1)) subjects. Mean ankle plantar flexor moment magnitudes did not differ between groups. Rearfoot directed mean anterior-posterior COPP locations and greater plantar force magnitudes/body weight suggests that subjects with genu varus or genu valgus relied more on the subtalar and midtarsal joint control function of the ankle plantar flexor muscle group for lower extremity dynamic postural control.

Strength of lower limb related to gait velocity and cadence in stroke patients

This study was undertaken to determine the relationship between two temporal components of gait (velocity and cadence) and the standardized static strength of seven lower extremity muscle groups of the paretic side of 20 patients who were hemiplegic following cerebrovascular accidents. Velocity and cadence were calculated from a timed gait trial over an eight-metre expanse of floor. Static strength was tested by a hand-held dynamometer, and the scores standardized against body weight. The muscles tested were hip flexors, extensors and abductors; the knee flexors and extensors; and the ankle dorsiflexors and plantar flexors. Correlations were significant (p &lt; 0.05) between both gait variables and the standardized strength of the hip extensor, knee flexor, ankle dorsiflexor, and ankle plantar flexor muscle groups. Also significant were the correlations between cadence and the standardized strength of the hip abductor and knee extensor muscles. These relationships suggest that the strength of some muscle groups of the paretic lower extremity may be of functional importance and worthy of measurement.

Plantar flexor strength testing using the cybex isokinetic dynamometer.

Twenty male subjects and twenty female subjects in each of three age categories, 6 to 8 years, 14 to 16 years, and 23 to 28 years, were tested on the Cybex Isokinetic Dynamometer to obtain normative strength values for the ankle plantar flexor muscle group. Values were established for both isokinetic and isometric contractions at two speeds. The results indicate that age and weight are the significant variables in determining strength scores.