Soleus Gastrocnemius Research Articles

1P1-H09 局所振動刺激に対する重心動揺変化に着目した腰痛に関する考察

We investigated the response of postural sway during local vibratory stimulation of elderly people with/without low back pain in standing position by using our developed variable frequency vibratory stimulation device and a gravicorder. The vibratory stimulations of 30, 60, 150, or 240Hz were applied to the subjects' lumbar multifidus or gastrocnemius soleus muscles. As a result, statistical significant differences appeared in the relative proprioceptive weighting (RPW) ratios with_30Hz and 240Hz between elderly people with/without low back pain. Moreover it was found that there are correlations between the RPW with 30Hz and the Japanese Orthopaedic Association score, and between the RPW with 240Hz and the visual analogue scale of low back pain.

Changes in the Gene c-fos Expression in the Rat Spinal Cord after Suppression of Activity of the Cerebral Monoaminergic Systems

We detected changes in the gene c-fos expression induced by activation of muscle afferents in the rat spinal cord after systemic introduction of reserpine (irreversible suppressor of vesicular transporter of monoamines, 1.5 mg/kg, intraperitoneally) and with no action of this agent. Numbers of Fosimmunoreactive (Fos-ir) neurons were calculated in the gray matter of the lumbar spinal segments after unilateral vibrational stimulation (VS) of the Achilles tendon of the mm. gastrocnemius–soleus. In the spinal cord of rats preliminarily injected with reserpine, greater numbers of Fos-ir neurons were observed; these units were localized mostly in layers 4–7 and in the nucl. intermediolateralis (35.4 ± 1.6 and 16.7 ± 0.9 positive neurons per 40 μm-thick slice) of segments L1–L2, and also in layers 4–7 and layer 9 (Fos-ir motoneurons) of segments L4–L5 (51.7 ± 3.4 and 11.4 ± 1.5 labeled units, respectively). The numbers of activated cells in the above structures of the spinal cord after VS but without preliminary injections of reserpine were, on average, 25.6 ± 1.4 and 3.5 ± 0.5, 27.8 ± ± 0.9 and 6.9 ± 0.3 units, respectively. Most ipsilateral Fos-ir motoneurons (86%) were localized in the lateral pool of layer 9, and only 14% of labeled motoneurons were localized in its medial regions. The results obtained show that weakening of monoaminergic influences resulting from administration of reserpine is accompanied by increase in the activity of intraspinal neuronal networks activated by proprioceptive afferent volleys, and the effects of the above inputs on spinal motoneurons and sympathetic preganglionic neurons are intensified. Weakening of inhibitory control, realized by inhibitory interneurons in the pathways of transmission of excitatory influences from muscle afferents to motoneurons, which was observed in our experiments after suppression of monoaminergic modulatory systems, can be considered a significant factor responsible for the development of rigidity/spasticity of the limb muscles manifested in neurodegenerative diseases and after traumas of the spinal cord.

Use of local muscle flaps to cover leg bone exposures.

To evaluate the use of the medial gastrocnemius muscle and/or soleus muscle flaps as surgical treatment of the leg bone exposure. We retrospectively analyzed the medical records of patients undergoing transposition of the medial gastrocnemius and / or soleus for treating exposed bone in the leg, from January 1976 to July 2009, gathering information on epidemiological data, the etiology the lesion, the time between the initial injury and muscle transposition, the muscle used to cover the lesion, the healing evolution of the skin coverage and the function of the gastrocnemius-soleus unit. 53 patients were operated, the ages varying between nine and 84 years (mean age 41); 42 were male and 11 female. The main initial injury was trauma (84.8%), consisting of tibia and / or fibula fracture. The most frequently used muscle was the soleus, in 40 cases (75.5%). The rank of 49 patients (92.5%) was excellent or good outcome, of three (5.6%) as regular and of one (1.9%) as unsatisfactory. the treatment of bone exposure with local muscle flaps (gastrocnemius and/or soleus) enables obtaining satisfactory results in covering of exposed structures, favoring local vascularization and improving the initial injury. It offers the advantage of providing a treatment in only one surgical procedure, an earlier recovery and reduced hospital stay.

Muscle edema of the lower limb determined by MRI in Asian hypokalaemic periodic paralysis patients

Objective:To determine the pattern of muscle edema occurring in the lower limb muscles of Asian hypokalaemic periodic paralysis (hypoPP) patients using magnetic resonance imaging (MRI). Specifically, the relationship between muscle edema and muscle activity during daily use was examined by comparing the lower limb muscle MRI of healthy subjects following exercise and hypoPP patients.Methods:Twenty Asian patients (mean age: 29·3±7·53 years) clinically diagnosed with hypoPP were enrolled in the present study. Ten healthy subjects were also enrolled. Direct automated DNA sequencing of the S4 regions of CACNA1S and SCN4A in all hypoPP patients was performed. The upper and lower legs of all hypoPP patients during the time interval between attacks and healthy subjects pre- and post-exercise were examined on a 3 T system with T2-weighted fat saturation sequence. Images were evaluated by means of a region of interest analysis. A scoring from 0 to 3 was used to compare the degree of muscle edema among individual muscles.Results:Three hypoPP patients were identified with mutations in the screened genes: R1239H and R900S of CACNA1S and R672H of SCN4A. The lower leg muscles of both hypoPP patients and healthy subjects after exercise displayed significantly higher MRI signal intensities compared to healthy subjects before exercise (P < 0·0001 and P < 0·0001, respectively). In contrast, there was no significant change in the upper leg muscle signal intensities of hypoPP patients and healthy subjects following exercise compared to pre-exercise healthy subjects (P = 0·7598 and P = 0·9651, respectively). In the hypoPP patient group, high signal intensity in the upper leg muscles was seen only in the patient with the R1239H mutation. In the lower legs, muscle edema was most frequently seen in the gastrocnemius lateralis, soleus, and gastrocnemius medialis in the hypoPP patient group. Furthermore, the degree of muscle edema was the greatest in these muscles. This similar pattern of muscle edema was also seen in healthy subjects after exercise.Conclusions:In Asian hypoPP patients, muscle edema as well as the underlying abnormal ion distributions across the muscle membrane is present even during the time interval between attacks of muscle weakness. The muscles of the lower leg are more likely to be edematous than muscles of the upper leg since these muscles are more actively used in daily life. Thus, muscles subjected to high activity are more likely to be edematous and sodium-overloaded.

Histomorphometric Evaluation of Soleus and Lateral Gastrocnemius Muscles of Animals Submitted to Pharmacological Manipulation with Fluoxetine

La manipulacion farmacologica con inhibidores selectivos de la recaptacion de la serotonina (ISRS) pueden cambiar el funcionamento del sistema serotoninergico y facilitar o inhibir la accion de este sistema, induciendo cambios en la morfologia del musculo esqueletico de ratones. El objetivo fue analizar los efectos de la manipulacion farmacologica neonatal con fluoxetina en el desarrollo de la masa muscular, numero de nucleos y area de la seccion transversa de las fibras de los musculos soleo y gastrocnemio lateral. Se utilizaron 24 ratones Wistar machos, de 30 y 90 dias de edad, tratados con solucion salina (NaCl 0,9%, 1m/100 g de peso corporal) y fluoxetina (1 mg; 1 ml/100 g de peso corporal). Los animales fueron divididos en grupos con solucion salina (GS-30 y GS-90) y fluoxetina (GF-30 y GF-90). El grupo tratado con fluoxetina mostro una reduccion de peso (g) de los musculos soleo (p=0,0046) y gastrocnemio lateral (p=0,02) en 90 dias. Ademas, se observo en este mismo grupo una reduccion de nucleos en 30 dias (M. soleo, p<0,001; M. gastrocnemio lateral, p0,007) asi como en el periodo de 90 dias (M. soleo, p=0,002; M. gastrocnemio lateral, p0,038). Tambien se observo reduccion del area de la seccion transversal en los animales tratados con fluoxetina durante el periodo de 30 dias (M. soleo, p=0,03; M. gastrocnemio lateral, p= 0,041;) y 90 dias (M. soleo, p=0,042; M. gastrocnemio lateral, p=0,012). El tratamiento con fluoxetina durante el periodo critico del desarrollo del sistema nervioso de ratones, induce cambios prematuros en la estructura de la fibra muscular, los que parecen estar relacionados con la reduccion de peso de los musculos soleo y gastrocnemio en una fase tardia de vida del animal. En consecuencia, la dosis utilizada de ISRS, sugiere un efecto inhibidor de la 5-HT, en relacion a las variables estudiadas sobre el desarrollo del tejido muscular esqueletico de ratones.

Range of motion, neuromechanical, and architectural adaptations to plantar flexor stretch training in humans

The neuromuscular adaptations in response to muscle stretch training have not been clearly described. In the present study, changes in muscle (at fascicular and whole muscle levels) and tendon mechanics, muscle activity, and spinal motoneuron excitability were examined during standardized plantar flexor stretches after 3 wk of twice daily stretch training (4 × 30 s). No changes were observed in a nonexercising control group (n = 9), however stretch training elicited a 19.9% increase in dorsiflexion range of motion (ROM) and a 28% increase in passive joint moment at end ROM (n = 12). Only a trend toward a decrease in passive plantar flexor moment during stretch (-9.9%; P = 0.15) was observed, and no changes in electromyographic amplitudes during ROM or at end ROM were detected. Decreases in H(max):M(max) (tibial nerve stimulation) were observed at plantar flexed (gastrocnemius medialis and soleus) and neutral (soleus only) joint angles, but not with the ankle dorsiflexed. Muscle and fascicle strain increased (12 vs. 23%) along with a decrease in muscle stiffness (-18%) during stretch to a constant target joint angle. Muscle length at end ROM increased (13%) without a change in fascicle length, fascicle rotation, tendon elongation, or tendon stiffness following training. A lack of change in maximum voluntary contraction moment and rate of force development at any joint angle was taken to indicate a lack of change in series compliance of the muscle-tendon unit. Thus, increases in end ROM were underpinned by increases in maximum tolerable passive joint moment (stretch tolerance) and both muscle and fascicle elongation rather than changes in volitional muscle activation or motoneuron pool excitability.

P324: CNE study of H reflex topography in human calf muscles discloses a dynamic field of motor unit potentials (MUPs) in health and disease

P324: CNE study of H reflex topography in human calf muscles discloses a dynamic field of motor unit potentials (MUPs) in health and disease

Gastrocsoleus recession techniques: an anatomical and biomechanical study in human cadavers.

Lengthening of the conjoined tendon of the gastrocnemius aponeurosis and soleus fascia is frequently used in the treatment of equinus deformities in children and adults. The Vulpius procedure as described in most orthopaedic texts is a division of the conjoined tendon in the shape of an inverted V. However, transverse division was also described by Vulpius and Stoffel, and has been reported in some clinical studies. We studied the anatomy and biomechanics of transverse division of the conjoined tendon in 12 human cadavers (24 legs). Transverse division of the conjoined tendon resulted in predictable, controlled lengthening of the gastrocsoleus muscle-tendon unit. The lengthening achieved was dependent both on the level of the cut in the conjoined tendon and division of the midline raphé. Division at a proximal level resulted in a mean lengthening of 15.2 mm (sd 2.0, (12 to 19), which increased to 17.1 mm (sd 1.8, (14 to 20) after division of the midline raphé. Division at a distal level resulted in a mean lengthening of 21.0 mm (sd 2.0, (18 to 25), which increased to 26.4 mm (sd 1.4, (24 to 29) after division of the raphé. These differences were significant (p < 0.001).

Does patellar tendon shortening improve the outcome of multilevel surgery in CP children with flexed knee gait?—A randomized clinical trial

The identification of gait patterns in cerebral palsy offers a common language for clinicians and contributes to management algorithms. We describe a quantitative classification of sagittal gait patterns based on the plantarflexor–knee extension couple index. This consists of a scatter plot based on ankle and knee scores, and allows objective identification of the sagittal gait pattern.Sagittal kinematic data from 200 limbs of 100 patients with bilateral spastic cerebral palsy were utilized to validate the algorithm against the assessment of a clinician with expertise in gait pattern identification. A dataset of 776 cerebral palsy patients, 1552 limbs, was used to compare the sagittal gait patterns against k-means statistical clustering. The classification was further explored with respect to the knee kinetics during the middle of stance and physical examination measurements of the gastrocnemius–soleus complex. Two supplementary materials (Appendices 2 and 3) provide in-depth discussion about statistical properties of the plantarflexor–knee extension couple index as well as its relationship with statistical clustering.The plantarflexor–knee extension index achieved 98% accuracy and may be suitable for the computational classification of large patient cohorts and multicentre studies. The sagittal gait patterns were strongly related to k-means statistical clustering and physical examination of the gastrocnemius–soleus complex. Patients in crouch gait had normal soleus and gastrocnemius lengths but spasticity in the gastrocnemius. Patients in jump gait exhibited a short gastrocnemius and soleus and gastrocnemius spasticity. Patients in true equinus presented with a moderately contracted soleus and gastrocnemius and gastrocnemius spasticity. Patients in apparent equinus did not show abnormal physical examination measurements for the gastrocnemius–soleus complex.

Reflex inhibition of cutaneous and muscle vasoconstrictor neurons during stimulation of cutaneous and muscle nociceptors

Cutaneous (CVC) and muscle (MVC) vasoconstrictor neurons exhibit typical reflex patterns to physiological stimulation of somatic and visceral afferent neurons. Here we tested the hypothesis that CVC neurons are inhibited by stimulation of cutaneous nociceptors but not of muscle nociceptors and that MVC neurons are inhibited by stimulation of muscle nociceptors but not of cutaneous nociceptors. Activity in the vasoconstrictor neurons was recorded from postganglionic axons isolated from the sural nerve or the lateral gastrocnemius-soleus nerve in anesthetized rats. The nociceptive afferents were excited by mechanical stimulation of the toes of the ipsilateral hindpaw (skin), by hypertonic saline injected into the ipsi- or contralateral gastrocnemius-soleus muscle, or by heat or noxious cold stimuli applied to the axons in the common peroneal nerve or tibial nerve. The results show that CVC neurons are inhibited by noxious stimulation of skin but not by noxious stimulation of skeletal muscle and that MVC neurons are inhibited by noxious stimulation of skeletal muscle but not by noxious stimulation of skin. These inhibitory reflexes are mostly lateralized and are most likely organized in the spinal cord. Stimulation of nociceptive cold-sensitive afferents does not elicit inhibitory or excitatory reflexes in CVC or MVC neurons. The reflex inhibition of activity in CVC or MVC neurons generated by stimulation of nociceptive cutaneous or muscle afferents during tissue injury leads to local increase of blood flow, resulting in an increase of transport of immunocompetent cells, proteins, and oxygen to the site of injury and enhancing the processes of healing.

OmijaFruit Extract Improves Endurance and Energy Metabolism by UpregulatingPGC-1α Expression in the Skeletal Muscle of Exercised Rats

This study was conducted to examine the effects of omija fruit extract on the endurance and energy metabolism of rats trained under a progressive loaded exercise program. Thirty male Sprague-Dawley rats (6 weeks old) were divided into three groups according to exercise and experimental diets for 6 weeks: the sedentary control (SC) group (n=10), the exercise control (EC) group (n=10), and the exercise group supplemented with 0.6% w/w omija extract (OM; n=10). The omija supplement significantly extended the running endurance time compared with the EC group. The soleus muscle weight was significantly higher in the OM group compared with the EC group and the plasma lactate and ammonia levels were significantly lower in the OM group than in the EC group. Plasma glucose, free fatty acid, and gastrocnemius muscle glycogen concentrations were also significantly lower in the OM group compared with the EC group. The lactate dehydrogenase activity was significantly higher in the gastrocnemius muscle of the OM group compared with the EC group. Expression of the peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) mRNA in the gastrocnemius muscle and soleus muscle were significantly elevated in the OM group and the soleus muscle peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyltransferase 1b (CPT1b), and β-hydroxyacyl coenzyme A dehydrogenase (β-HAD) mRNA expressions showed the same tendency. Taken together, these results show that supplementation of omija fruit extract enhances endurance and energy metabolism by upregulating the PGC-1α expression in the skeletal muscle.

Effects of supramalleolar osteotomies for ankle osteoarthritis on foot kinematics and lower leg muscle activation during walking

BackgroundEarly stages of asymmetric ankle osteoarthritis can be treated by joint preserving supramalleolar osteotomies that surgically realign the ankle and unload degenerated cartilage. While studies have already shown pain relief and functional improvements, the effects on gait biomechanics are largely unknown. This study investigated patients' gait pattern after supramalleolar osteotomies by focusing on foot kinematics and lower leg muscle activation. MethodsAn instrumented three-dimensional gait analysis with simultaneous electromyography of gastrocnemius medialis and lateralis, soleus, peroneus longus, and tibialis anterior muscles was performed on 12 patients with ankle osteoarthritis, seven of which were followed up 12–18months postoperatively. Additionally, seven different long-term follow-up patients (8–9years postoperatively) and 15 healthy control subjects were measured. The waveforms of the foot kinematics and muscle activation were analyzed using principal component analysis. FindingsCompared to healthy controls, principal component scores that affected the sagittal range of motion of the hindfoot and hallux were lower in all patient groups, while scores that affected the timing of the peaks in the sagittal forefoot motion were mainly altered in short-term follow-up patients. Lower principal component scores in patients with ankle osteoarthritis and short-term follow-up patients resulted in a less pronounced peak activation of gastrocnemius medialis and soleus. InterpretationBoth postoperative patient groups showed similar adaptations in their gait pattern as those observed in patients with ankle osteoarthritis. These changes are probably related to the lower ankle mobility. However, the reduced mobility seems to affect the patients' well-being less than a painful joint.

Changes in Tetrodotoxin-Resistant C-Fibre Activity during Fatiguing Isometric Contractions in the Rat

It is by now well established that tetrodotoxin-resistant (TTX-R) afferent fibres from muscle in the rat exhibit a multisensitive profile, including nociception. TTX-R afferent fibres play an important role in motor control, via spinal and supraspinal loops, but their activation and function during muscle exercise and fatigue are still unknown. Therefore, the specific effect of isometric fatiguing muscle contraction on the responsiveness of TTX-R C-fibres has been investigated in this study. To quantify the TTX-R afferent input we recorded the cord dorsum potential (CDP), which is the result of the electrical fields set up within the spinal cord by the depolarisation of the interneurons located in the dorsal horn, activated by an incoming volley of TTX-R muscle afferents. The changes in TTX-R CDP size before, during and after fatiguing electrical stimulation of the gastrocnemius-soleus (GS) muscle have been taken as a measure of TTX-R C-unit activation. At the end of the fatiguing protocol, following an exponential drop in force, TTX-R CDP area decreased in the majority of trials (9/14) to 0.75±0.03% (mean ± SEM) of the pre-fatigue value. Recovery to the control size of the TTX-R CDP was incomplete after 10 min. Furthermore, fatiguing trials could sensitise a fraction of the TTX-R C-fibres responding to muscle pinch. The results suggest a long-lasting activation of the TTX-R muscle afferents after fatiguing stimulation. The role of this behaviour in chronic muscle fatigue in connection with pain development is discussed. Accumulation of metabolites released into the interstitium during fatiguing stimulation might be one of the reasons underlying the C-fibres’ long-lasting activation.

A rodent model of partial muscle re-innervation

BackgroundThere is limited appreciation of the risks and benefits of the few salvage treatment options available for inadequate motor function following incomplete spontaneous recovery or surgical repair of major peripheral nerve injuries. The lack of a reliable and economical animal model has hindered laboratory investigation into this difficult clinical problem. We propose a straightforward and reproducible rodent model of partial re-innervation of a hind limb muscle. New methodTwelve Sprague-Dawley rats underwent identical surgical manipulations: the left tibial nerve was isolated, partially transected (2/3rds), and the remaining intact portion crushed. Eight weeks later, bilateral (1) gastrocnemius (2) soleus and (3) flexor digitorum longus muscles underwent maximal isometric contraction force testing before being excised and weighed. ResultsOnly the gastrocnemius muscles were statistically weaker (p<0.05) in the experimental limb compared with the contralateral (control) limb. There was no difference in muscle weights between experimental and control sides. Comparison with existing methodsOur model differs from other published models by: allowing time for compensatory axonal sprouting as would be seen in clinical scenarios, precisely identifying the portion of the tibial nerve to be transected to ensure reproducibility, and achieving temporary but complete denervation by crushing the intact portion of the nerve. ConclusionsControlled partial transection and crushing of the rodent tibial nerve results in a consistently partially re-innervated and clinically weakened gastrocnemius muscle that can serve as a model in studying incomplete recovery following nerve injury.

Lengthening of the Gastrocnemius-Soleus Complex

Lengthening of the gastrocnemius-soleus complex is frequently performed for equinus deformity. Many techniques have been described, but there is uncertainty regarding the precise details of some surgical procedures. The surgical anatomy of the gastrocnemius-soleus complex was investigated, and standardized approaches were developed for the procedures described by Baumann, Strayer, Vulpius, Baker, Hoke, and White. The biomechanical characteristics of these six procedures were then compared in three randomized trials involving formaldehyde-preserved human cadaveric lower limbs. After one of the lengthening procedures was performed, a measured dorsiflexion force was applied across the metatarsal heads with use of a torque dynamometer. Lengthening of the gastrocnemius-soleus complex was measured directly, by measuring the gap between the ends of the fascia or tendon. The gastrocnemius-soleus musculotendinous unit was subdivided into three zones. In Zone 1, it was possible to lengthen the gastrocnemius-soleus complex in either a selective or a differential manner-i.e., to lengthen the gastrocnemius alone or to lengthen the gastrocnemius and soleus by different amounts. The procedures performed in this zone (Baumann and Strayer procedures) were very stable but were limited with regard to the amount of lengthening achieved. Zone-2 lengthenings of the conjoined gastrocnemius aponeurosis and soleus fascia (Vulpius and Baker procedures) were not selective but were stable and resulted in significantly greater lengthening than Zone-1 procedures (p < 0.001). In Zone 3 (Hoke and White procedures), lengthenings of the Achilles tendon were neither selective nor stable but resulted in significantly greater lengthening than Zone-1 or 2 procedures (p < 0.001). Surgical procedures for the correction of equinus deformity by lengthening of the gastrocnemius-soleus complex vary in terms of selectivity, stability, and range of correction. Procedures for the correction of equinus deformity have different anatomical and biomechanical characteristics. Clinical trials are needed to determine whether these differences are of clinical importance. It may be appropriate for surgeons to select a procedure involving the zone best suited to the clinical needs of a specific patient.

Relation between microcurrent therapy and satellite cells in the regeneration of induced skeletal muscle injury in rat

Background Severe injuries in skeletal muscle result in muscle weakness, which delays recovery and contributes to progressive decline in muscle function. Microcurrent therapy is a novel treatment method used in soft-tissue injury and tissue regeneration therapy. The regenerative capacity of skeletal muscle tissue resides in satellite cells, the quiescent adult stem cells. Aim The present work aimed at investigating the possible relation between microcurrent therapy and satellite cells in regeneration of induced skeletal muscle injury in albino rats. Materials and methods Twenty-four male albino rats were divided into 2 groups: Control group and experimental group (II): rats were subjected to gastrocnemius-soleus muscle injury (subgroup IIa), they were subdivided into subgroups IIa1 & IIa2 sacrificed 1 and 3 weeks after injury respectively. Subgroup IIb: Rats were subjected to muscle injury and micro-current electric stimulator, was applied for 20 minutes for three sessions per week. The animals were subdivided into subgroups IIb1 and IIb2 sacrificed 1 and 3 weeks following the day of injury. Muscle sections were stained with hematoxylin and eosin, alpha smooth muscle actin (α-SMA) and CD34 immunostaining. Morphometric studies and statistical analysis were performed. Results Atypical fibers were widely separated by connective tissue cells and revealed partial loss of striations in subgroup IIa. Some fibers recruited strong acidophilic sarcoplasm with focal vacuolations in subgroup IIa1. In subgroup IIb1, some typical fibers, some centrally located nuclei, and a few deeply acidophilic fibers were found. Striations were found in some areas of the sarcoplasm. In subgroup IIb2 striations were found in most areas of the sarcoplasm. A significant decrease in the mean area of atypical fibers, a significant increase in the mean area% of α-smooth muscle actin-positive cells, and a significant increase in the mean area% of CD34-positive cells were found in subgroup IIb compared with subgroup IIa. Conclusion A definite therapeutic effect of the microcurrent was found on induced skeletal muscle injury, which was time dependent. This effect was proved to be related to satellite cell activation.

The Effectiveness of a Gastrocnemius–Soleus Stretching Program as a Therapeutic Treatment of Plantar Fasciitis

Clinical Scenario:Injury to the plantar fascia, whether acute or chronic, is common among many populations. A conventional multiple-treatment approach is commonly administered by health care providers, consisting of controlling inflammation, managing pain, and promoting healing. Frequently, the initial treatment for plantar fasciitis is targeted at increasing dorsiflexion range of motion by stretching the gastroc-soleus musculature. It has been theorized that inflexibility of the gastroc-soleus complex can lead to excessive pronation and overcompensation of the plantar fascia at the first metatarsal phalangeal joint, therefore increasing the stress at the medial calcaneal insertion. Therefore, it is deemed that gastrocnemius–soleus stretches are a beneficial treatment in the initial stage of a plantar fasciitis treatment or rehabilitation program.Focused Clinical Question:Is a gastrocnemius–soleus stretching program, as a stand-alone treatment variable, effective in the treatment of plantar fasciitis?

Arylpiperazines as fatty acid transport protein 1 (FATP1) inhibitors with improved potency and pharmacokinetic properties

The discovery and optimization of a novel series of FATP1 inhibitors are described. Through the derivatization process, arylpiperazine derivatives 5k and 12a were identified as possessing potent in vitro activity against human and mouse FATP1s as well as excellent pharmacokinetic properties. In vivo evaluation of triglyceride accumulation in the liver, white gastrocnemius muscle and soleus is also described.

Electrical and Force Responses of the Shin Muscles of Rats after Unilateral Compression of the Sciatic Nerve and Systemic Introduction of Gamma-Hydroxybutyrate

In acute experiments on rats, we examined the effects of course systemic introduction of sodium gammahydroxybutyrate (NaGHB, 100 mg/kg, i.p., daily within 3 weeks) on consequences of compression of the right sciatic nerve, SN. In the control group, the nerve was compressed, but NaGHB was not injected. Electrical and force responses of the m. gastrocnemius+soleus (GS) and m. tibialis anterior (TA) evoked by stimulation of the n. tibialis comm. and n. peroneus comm., respectively, at the side of SN impairment and the opposite intact side were recorded. Compression of the SN induced in animals of the control group (with no injections of NaGHB) considerable increases in the values of the threshold and chronaxia of the stimulated nerve, decreases in the amplitude of EMG responses of the muscles, increases in the latencies of these reactions, and also decreases in the force responses developed at single and tetanic isometric contractions of the above muscles. At the side of SN compression, graphs of recovery of the second muscle response under conditions of paired stimulation of the nerves were shifted toward greater interstimulus intervals. Course introduction of NaGHB resulted in more than a twofold increase in the thresholds upon stimulation of the nerves; at the same time, the chronaxia values decreased. The amplitudes of EMG responses of the muscles after NaGHB injections became smaller than in the control, and the latencies of these responses increased. Under these conditions, curves of recovery of the second response at paired stimulation were shifted toward shorter interstimulus intervals. Introduction of NaGHB provided noticeable increases in the force responses of the tested muscles. Such changes were observed bilaterally, and the relative intensities of the corresponding modifications at the side of SN compression and the intact side were close to each other. Possible mechanisms of the effect of NaGHB on the state of the nerve/muscle apparatus of the limb after compression of a large nerve trunk resulting in the development of traumatic neuropathy are discussed.

Dose–response effects of customised foot orthoses on lower limb muscle activity and plantar pressures in pronated foot type

Customised foot orthoses (FOs) featuring extrinsic rearfoot posting are commonly prescribed for individuals with a symptomatic pronated foot type. By altering the angle of the posting it is purported that a controlled dose–response effect during the stance phase of gait can be achieved, however these biomechanical changes have yet to be characterised. Customised FOs were administered to participant groups with symptomatic pronated foot types and asymptomatic normal foot types. The electromyographic (EMG) and plantar pressure effects of varying the dose were measured. Dose was varied by changing the angle of posting from 6° lateral to 10° medial in 2° steps on customised devices produced using computer aided orthoses design software. No effects due to posting level were found for EMG variables. Significant group effects were seen with customised FOs reducing above knee muscle activity in pronated foot types compared to normal foot types (biceps femoris p=0.022; vastus lateralis p<0.001; vastus medialis p=0.001). Interaction effects were seen for gastrocnemius medialis and soleus. Significant linear effects of posting level were seen for plantar pressure at the lateral rearfoot (p=0.001), midfoot (p<0.001) and lateral forefoot (p=0.002). A group effect was also seen for plantar pressure at the medial heel (p=0.009). This study provides evidence that a customised FOs can provide a dose response effect for selected plantar pressure variables, but no such effect could be identified for muscle activity. Foot type may play an important role in the effect of customised orthoses on activity of muscles above the knee.