Head Of Gastrocnemius Muscle Research Articles

INTRARATER AND INTERRATER RELIABILITY OF MUSCLE TONE, ELASTICITY AND STIFFNESS CHARACTERISTICS MEASUREMENTS BY MYOTON-3 IN HEALTHY CHILDREN AGED 5–7 YEARS

Background. Research literature highlights the need to use objective assessment tools to quantify muscle tone because all typically used clinical scales of muscle tone have reliability problems. Though hand-held device Myoton-3 has been used in research with children, its reliability has not been established. The aim of this study was to investigate intrarater and interrater reliability of muscle tone, elasticity and stiffness measurements by Myoton-3 in healthy children aged 5–7 years. Methods. A total of 30 healthy children aged between 5 and 7 years participated in the study. Myoton-3 device was used by two measurers to assess tibialis anterior (TA), rectus femoris (RF), biceps brachii (BB), medial head of gastrocnemius (GM), biceps femoris (BF), trapezius (TR) and triceps brachii (TB) muscle tone, elasticity and stiffness values. Measurements were conducted for intrarater reliability on two consecutive days and for interrater reliability on the same day. Results. Intrarater reliability expressed as intra-class correlation of frequency, decrement and stiffness characteristics measurements was moderate to high, between 0.60–0.72, while TR muscle ICC was low. Interrater reliability expressed as intra-class correlation of the frequency, decrement and stiffness characteristics measurements was high to very high, between 0.72–0.91, while TR muscle ICC was low. Conclusion. Moderate to high (0.60–0.72) intrarater reliability and high to very high interrater reliability (0.72– 0.91) was established for Myoton-3 measurements in healthy children aged 5–7 years. The Myoton-3 is a reliable device for measuring skeletal muscle tone, elasticity and stiffness in preschool children.

Advances in muscle imaging for Emery-Dreifuss muscular dystrophy

Laminopathies are a heterogeneous group of disorders related to alterations on genes coding for proteins of the nuclear envelope. Among these clinical entities, there are several diseases affecting mainly the cardiac and skeletal muscles. These disorders include forms with a selective cardiac compromise and muscular dystrophies (autosomal and X-linked forms of Emery-Dreifuss muscular dystrophy, Limb girdle muscular dystrophy 1B, LMNA-related congenital muscular dystrophy and other rare clinical entities). We performed imaging studies on a large cohort of subjects bearing either LMNA or EMD gene mutations; each patient enrolled displayed variable compromise on posterior legs’ muscles, ranging from mild compromise on soleus and medial head of gastrocnemius to overt alterations on soleus, medial head of gastrocnemius [1,3]. Of note, we saw that even subjects presenting with clinically selective cardiac compromise displayed, on imaging studies, variable alterations on skeletal muscles. This findings showed a continuum in skeletal muscles compromise among different phenotypes related to LMNA or EMD gene mutations and lead to hypothesize a common mechanism in the process of damage of skeletal muscles fibers.

Medial Sural Artery Perforator Flap: Using the Superficial Venous System to Minimize Flap Congestion.

Use of the pedicled medial sural artery perforator (MSAP) fasciocutaneous flap has been widely reported in the literature for ipsilateral lower limb reconstruction. Depending on defect location, the MSAP flap may be utilized as a propeller or V-Y advancement flap [1]. This perforator flap is typically based on the proximal perforator of the medial sural artery supplying the gastrocnemius muscle. One of the main issues encountered when performing an MSAP flap is venous congestion [2], a commonly described complication in other perforator based flaps [3]. We describe a useful technique to overcome this problem by including the superficial vein into the original flap design. A 57-year-old woman was referred to our department with a malignant melanoma in the left popliteal fossa. Histologically the lesion was reported as having a 0.8 mm Breslow thickness. The resulting defect was 5 cm×5.5 cm (Fig. 1). Handheld Doppler was used to locate and mark the perforators preoperatively across the medial head of gastrocnemius. Although more accurate methods can be used to map the perforator, handheld Doppler offers time efficiency and reduces input from radiological investigations [4]. Flap harvest commenced with an incision placed above the medial border of the medial head of the gastrocnemius. A branch of the long saphenous vein superficial to the fascia was encountered and preserved and seen to enter the medial side flap (Fig. 2). Two perforators were identified. The vein was mobilized free from the lateral skin flap to provide enough mobility for flap advancement. The flap was raised subfascially from distal to proximal with identification and preservation of two MSAP (Fig. 3). The two perforators were skeletonised with minimal intra-muscular dissection. This ensured the flap could be advanced proximally 5 cm in a V-Y fashion and inset (Fig. 4). No venous congestion was encountered following flap inset (Fig. 5). This case report suggests that venous augmentation with the superficial branch of the long saphenous vein in MSAP flap improves venous drainage, as has previously been described by Hallock [2]. It can most effectively be utilized in V-Y advancement MSAP flaps, where the movement is unidimensional, as no rotation of the flap is required which may lead to vascular compromise and consequent flap compromise. In the distally based flap, the technique of phlebotomy to relieve flap congestion via an exteriorised segment of short saphenous vein has been described, contributing to favourable flap survival [5]. Short saphenous branch preservation is a useful and relatively simple method of reducing the risk of MSAP flap congestion without prolonging dissection time. Fig. 1 Wide local excision of malignant melanoma left popliteal fossa with resulting 5 cm ×5.5 cm defect. V-Y advancement flap designed based on a dominant perforator marked with an X. Fig. 2 The medially located superficial branch of the short saphenous vein. Fig. 3 Two median sural artery perforators were identified and dissected on the lateral aspect of the flap. Fig. 4 V-Y flap raised subfascially and advanced into defect. Fig. 5 Medial sural artery perforator flap 4 months postoperatively.

Gastrocnemius tendinosis—A frequent finding on MRI knee examination

ObjectiveGastrocnemius tendinosis (GT) is one potential cause for posterior knee pain, commonly overlooked on clinical examinations and imaging. This study assesses the frequency of GT on MR imaging in a convenience sample based on a database search and associations with other articular pathologies and clinical findings. Subjects and methodsWith IRB approval, retrospective review was completed on 300 randomly selected MR knee exams performed from February 2009 to June 2010. Following de-identification, axial T2 and sagittal PD images, with or without fat suppression, were reviewed by 2 radiologists. The gastrocnemius tendon femoral attachments were graded as normal, mild (few cysts, thickening, intermediate signal) or severe GT (multiple cysts, marrow edema, tear). Select associated MR findings of internal derangement were documented. Clinical charts were reviewed for clinical presentation, physical exam findings, and select demographics. ResultsThe inter-observer reliability for presence/grading of GT was very high (kappa statistic=0.97). Frequency of GT was 50.33%, most frequently involving medial head of gastrocnemius (63.6%). Grades of GT were 41.7% and 17.2% for mild and severe respectively. Univariate analysis showed statistically significant relationship between grade of GT with arthrosis (p=0.05) and clinical joint effusion (p=0.02). Multivariate analysis showed higher odds of severe GT for individuals with medial plus lateral GT. Statistical significance was noted for presence of both GT and ACL tear (13.9%; p=0.02). ConclusionSignificant findings of our analysis included GT presented with predominant involvement of medial head of gastrocnemius tendon, mild in severity, strong association with ACL tear, presented frequently as posterior knee pain, limited joint motion and clinical joint effusion. However, there was no statistically significant association between demographic features and medical comorbidities in the patients. Increased understanding of frequency of GT allows more accurate reporting of MR knee exam and systematic search for associated abnormalities.

A novel mutation in DNAJB6, p.(Phe91Leu), in childhood-onset LGMD1D with a severe phenotype

To identify and characterize genetic mutation in a Korean family with limb-girdle muscular dystrophy 1 (LGMD1), we analyzed in the affected family members clinical features, DNAJB6 by Sanger sequencing, muscle structures by magnetic resonance imaging (MRI), and functional consequences of the identified mutation using a zebrafish model. The clinical phenotypes along with identification of a novel c.271T > C (p.(Phe91Leu)) mutation in DNAJB6 led to the diagnosis of LGMD1D in the affected family members. This mutation presents unique clinical and radiological features compared with other DNAJB6 mutants. All affected members examined showed reduced pulmonary function, and had nasal voice and dysphagia except the two members who were thirteen and twelve years of age at the time of examination. Muscle phenotypes developed between 8 and 11 years of age and were more severe as compared to previously reported LGMD1D patients with mutant DNAJB6. Patients' MRI scans exhibited early involvement of the lateral head of gastrocnemius, in contrast to its late involvement in reported LGMD1D cases. Functional study using zebrafish embryos demonstrated that p.Phe91Leu elicits more severe muscle defects than the reported p.Phe93Leu and p.Pro96Arg mutations. We conclude that a novel p.(Phe91Leu) mutation in DNAJB6 is associated with severe childhood-onset LGMD1D.

Pattern of Fascicular Involvement in Midportion Achilles Tendinopathy at Ultrasound

Background:The Achilles tendon is composed of fascicles from the soleus and gastrocnemius muscles, which are identifiable as discrete components at anatomical dissection.Hypothesis:The pattern of fascicular involvement in Achilles tendinopathy may be characterized at ultrasound, and this characterization is reliable between different observers.Study Design:Cross-sectional diagnostic study.Level of Evidence:Level 3.Methods:One hundred cases of Achilles tendinopathy were retrospectively evaluated by 2 blinded musculoskeletal radiologists. Using a short-axis anatomical map, each case was categorized as involving the fascicular territories of the medial head of gastrocnemius, lateral head of gastrocnemius, soleus, or combinations of these, or as indeterminate.Results:Both radiologists agreed on the fascicular involvement pattern in 93 of 100 cases; 20 involved only medial gastrocnemius territories, 8 lateral gastrocnemius, 15 soleus, 3 medial and lateral gastrocnemius, 21 medial gastrocnemius and soleus, 9 soleus and lateral gastrocnemius, and 16 the entire tendon, and 1 case was classified as indeterminate. In 7 cases, the interpretations were discordant. The kappa value was calculated as 0.92 (95% CI, 0.86-0.98) in keeping with a high level of interobserver agreement.Conclusion:As assessed at ultrasound, most cases of Achilles tendinopathy involve the medial head of gastrocnemius and/or soleus fascicles.Clinical Relevance:The provided observational data will increase understanding of patterns of Achilles tendinopathy.

An Unusual Presentation of Bilateral Hypothenar Hammer Syndrome

popliteal artery with medial displacement suggestive of PAES. The patient was taken to the operating room for right popliteal artery exploration via posterior approach. A type III PAES was identified intraoperatively (Fig). The accessory slip of muscle from the medial head of gastrocnemius muscle was divided. A balloon thromboembolectomy was performed through a longitudinal arteriotomy and the artery was patched with bovine pericardium. Results: Postoperatively, the patient recovered well and was neurologically intact with normal pedal pulses. She was seen by obstetrics and underwent fetal heart rate monitoring. She was started on 81-mg aspirin daily and was discharged home on postoperative day 4. She was seen in follow-up by vascular surgery and in consultation with maternal fetal medicine because she was previously cared for by nurse midwives. Conclusions: Nonatheromatous popliteal artery pathology should be considered in young active patients who present with intermittent claudication or acute limb ischemia. The pregnant woman warrants a discussion of safe imaging modalities to establish a diagnosis and anesthesia considerations for surgical repair. Although we know strenuous exercise predisposes patients to symptomatic PAES, pregnancy is a hypercoagulable state and may be an independent risk factor.

Ultrasound Imaging of Torn Soleus Muscle

Figure 1. In comparison with the normal side, the left calf appeared markedly swollen, without noticeable ecchymosis. A 51-year-old man was referred for ultrasound (US) examination because of persistent left calf swelling for 3 months. The swelling developed abruptly after he had stumbled against a stone, sustaining an inversion injury to his ankle. He described calf pain and swelling but no ecchymosis. Three months after injury, active and passive range of motion of the ankle and toes were not limited, including ankle plantar flexion and toe flexion. Skin color and sensation also appeared normal over the swollen area (Figure 1). US imaging revealed a hyperechoic, homogeneous mass originating beneath the mid-portion of the Achilles tendon and ending at the posterior proximal tibia, with an intact distal musculotendinous junction of the medial gastrocnemius muscle (Supplemental Video and Figure 2A). The mass was observed to occupy the space between both heads of the gastrocnemius and deep plantar flexors (tibialis posterior, flexor digitorum profoundus and flexor hallucis longus), with overlying anechoic fluid (Supplemental Video and Figure 2B). The patient was eventually diagnosed with tear of the soleus muscle and an organized hematoma. The soleus muscle, originating from the fibula and medial border of the tibia, merges with the gastrocnemius muscle, forming the Achilles tendon and attaching on the calcaneus. Tear of the medial head of the gastrocnemius muscle at the musculotendinous junction (ie, “tennis leg”) is the more common calf muscle tear, and is typically caused by abrupt extension of the knee and simultaneous forced dorsiflexion of the ankle [1,2]. In this patient, there had been a severe ankle sprain with simultaneous knee buckling. As such, although his gastrocnemius muscle had been protected from overload, the soleus muscle had become vulnerable to the twisting force. In addition, we conclude that the lack of ecchymosis could be attributed to the intact

A posterior reversed L-shaped approach for the tibial plateau fractures—A prospective study of complications (95 cases)

PurposeThis study was aiming to investigate intraoperative and postoperative complications and outcomes of a posterior reversed L-shaped approach (PRLA) in the treatment of the tibial plateau fractures. MethodsInclusion criterion was tibial plateau fractures treated through the PRLA either separated or combined with other approaches. Main exclusion criterion was poly-trauma patients. Ninety-five patients with tibial plateau fractures from a prospectively collected database were included and followed in this study. The intraoperative and postoperative complications consisted of vascular and nerve injury, wound infection, dehiscence, haematoma, nonunion, skin necrosis and skin paresthesia. Hospital for Special Surgery Knee Score (HSS) was adopted to evaluate patients’ knee function while Short Form 36 Health Survey (SF-36) was used to investigate the patients’ general health status. ResultsPatients’ average age was 46.2 years old (range, 22.0–89.0). The fractures were mainly from high energy injuries involving posterior (and medial) column. 78 of 95 cases were combined with an additional anterolateral approach due to the lateral column involvement. The average follow-up was 52.0 months (range, 12.4–102.6). The total complications rate was 4.2% (4/95). Intraoperative complications occurred in two patients (2.1%). One suffered a popliteal artery injury resulted from an antero-posteriorly drilled K-wire. The patient had a loss of 7° knee extension at one year's follow-up. The other endured an injury of nutrient vessel within the medial head of gastrocnemius. Postoperative skin paresthesia occurred in two patients (2.1%). The other complications associated with the PRLA were not observed. The mean HSS score was 96.1 (range, 80–100). The mean SF-36 score was 94.2 (range, 80–100). ConclusionsThe posterior reversed L-shaped approach allows satisfied visualization of the medial and posterior tibial plateau and has promising clinical results with low complication occurrence. It can be recommended as a routine approach for the treatment of the tibial plateau fractures involving the posterior column.

Frequency analysis of electromyogram of the triceps surae muscle taken while the stroke patients walk

Background: Many groups have reported results of frequency analysis of electromyogram (EMG) while the muscle with spasticity contracts in stroke patients.However, very few reports on characteristics of the muscle with spasticity during exercise have been published, and the majority is static evaluation using Fast Fourier Transform (FFT). Purpose: We carried out and examined dynamic frequency characteristics of contraction characteristics of the triceps surae while the stroke patients walk using Wavelet Transform (WT) which analyzes temporal information and frequency information of conventional FFT at same time. Methods: Subject of the present study was nine healthy men (age 28.0± 2.83), healthy group (HG), and nine stroke patients (age 70.17± 9.38), stroke group (SG), who were in the recovery stage and the rehabilitation ward of our hospital. These patients have their hemiplegia after stroke, and can walk by themselves or while being supervised. We measured the dominant feet of the HG and the paralyzed legs of the SG. Surface EMGmonitored muscle activation while the subjects freely walked 10m on a walkway at the optimum speed. Also, a foot switch sensor was attached on the plantar part to identify a single walking cycle. EMGMaster (Ozawa Medical Instruments) was used for surface EMG to monitor medial and lateral heads of gastrocnemius muscle. The data after fourth steps from walking starts were analyzed. Integral EMG analysis and wavelet transform (12.5Hz to 200Hz) were carried out to any given data of three walking cycles. Calculated integrated values of both groups were normalized using the integrated values during a single walking cycle. Also, the frequency range was divided into two categories; a low-frequency band (LFB) of 45Hz and lower and highfrequency band of 75Hz and higher (HFB) to calculate the power density of HFB to LFB, H/L ratio, of each muscle. As a statistical analysis, the Wilcoxon signed-rank test was used to compare the integrated values and H/L ratio between the HG and SG. Results: Each evaluation item of the HG and SG was compared. The HG has a significantly high integrated value (p< 0.05), and the SG has significantly high H/L ratio (p< 0.05). Conclusion(s): Although muscle activity characteristics of the triceps surae of the stroke patients is low as an integrated value, the ratio of HFB is high as dynamic frequency characteristics. This indicates strong activity of fast fibers. By taking the facts of low integrated value and atrophy of the presence of fast-twitch fibers into account, synchronization defect in the motor units possibly caused a frequency rise. Implications: These findings are expected to help treatment to improve quality of muscle activity in rehabilitation for stroke patients to walk.

Bakers Cyst: A Case Report and its clinical significance

The Bakers or Popliteal cyst is a bursa seen between medial head Gastrocnemius and Semimembranosus. This bursa when present usually communicates with the cavity of Knee joint, most of the times being asymptomatic. They can occur due to any intra-articular pathology including bony inflammation, cartilaginous lesions, meniscal or ligament tear, etc. The symptomatic cases are mainly leading to pressure effects due to anatomical vulnerability of surrounding structures. Symptoms related to Popliteal vein compression and Tibial nerve entrapment are the most common clinical presentations. Although, Bakers cyst is a chronic disorder and after treatment also requires follow up to prevent relapses, it causes difficulty in differential diagnosis while presenting in acute state. Ultrasonographic examination and Magnetic Resonance Imaging are important tool to avoid misdiagnosis and inappropriate treatment. Surgical resection of the cyst is rarely indicated when intra-articular pathology cannot be diagnosed or its treatment is not responding.

Activity of lower limb muscles during treadmill running at different velocities.

[Purpose] The present study aimed to determine changes in muscle activity while moving on a treadmill at various speeds. [Subjects] The activities of the left vastus lateralis, vastus medialis, hip adductors, lateral head of gastrocnemius, medial head gastrocnemius, soleus, and tibialis anterior of 10 healthy male university students were analyzed. [Methods] University students walked, jogged, and ran for 10 minutes each in random order, and then myogenic potentials were measured 10 minutes later for 30 seconds. The flexion angle of the lower limb upon initial contact, mid stance, and toe off were measured. [Results] The average walking, jogging, and running speeds were 3.6 ± 0.4, 6.7 ± 0.6, and 10.4 ± 1.3 km/h, respectively. The average electromyographic activities of the vastus medial, tibialis anterior, medial head of gastrocnemius, and lateral head of gastrocnemius significantly differed. All muscles were more active during jogging and running than walking. Only the soleus was more active during running than walking, and the activities of the hip adductors and vastus lateralis did not significantly differ. [Conclusion] Velocity is faster and the angles of the lower limbs and ground reaction force (GRF) are larger during running than walking. The vastus medialis and soleus worked more easily according to the angle of the knee joint, whereas the tibialis anterior worked more easily at faster velocities and the medial and lateral heads of the gastrocnemius worked more easily with an increased GRF.

Clinical outcome with Botulinum toxin-A in spastic cerebral palsy children with equinus gait

Objective: Analysis of spastic equinus gait, ankle movements, and spasticity change in Indian cerebral palsy (CP) children. Design: Prospective study with follow up at 2 weeks and 2 months after injection. Setting: Department of Physical Medicine and Rehabilitation, AIIMS, New Delhi between 2009 and 2011. Participants: 22 Spastic CP children (12 diplegic and 10 hemiplegic), 14 males and 8 females aged 2-8 years (mean 4.44 years) having gastrocnemius spasticity with equinus gait. Intervention: Botulinum Toxin-A marketed as Botox® (Allergan, Inc.) was administered in both the medial and lateral heads of gastrocnemius. Dosage: 4 Unit/kg/muscle, maximum of 50 U per injection site, 50 U/ml with 0.9% normal saline dilution. After injection, the children continued participating in routine rehab exercise therapy and provided ankle foot orthosis. Main Outcome Measure(s): Temporospatial parameter of gait (stride, step length, cadence, velocity, percentage contact of foot with ground), Spasticity as per modified Ashworth Scale, active and passive range of motion at ankle. Results: Significant improvement (n = 34, P 90% of children in terms of comfort, ease of care, and walking. The improvement lasted for 2 months. Conclusions: Botulinum Toxin-A injection is effective in treatment of equinus gait with easy OPD procedure and minimal side effects which are very tolerable.

A-34 装着型筋硬度計によるストレッチング時の筋粘弾性計測 : 腓腹筋内側頭・外側頭の筋粘弾性変化の類似性調査(筋特性の計測と動作への影響)

A-34 装着型筋硬度計によるストレッチング時の筋粘弾性計測 : 腓腹筋内側頭・外側頭の筋粘弾性変化の類似性調査(筋特性の計測と動作への影響)

Bilateral popliteal entrapment syndrome associated with plantar flexion of a phenomenon

Popliteal artery entrapment syndrome (PAES) presents with intermittent claudication; however, in the later stages, acute ischemia can occur as a result of complete arterial occlusion or embolism. We present a patient that symptomatic with plantar flexion. PAES was diagnosed with magnetic resonance imaging (MRI) and angiography. In operation medial head of gastrocnemius was resected and popliteal artery resection end to end anastomosis technic was performed. After surgery patient discharged with no symptom and problem. Ischemic symptoms in the lower leg in young patients with extremity movement, PAES must be considered. Correct diagnosis for PAES are important for preventing deterioration in the patient’s clinical condition. Key words: Popliteal entrapment syndrome, Claudication intermittans, Plantar flexion, Medial head of gastrocnemius.

MORPHOLOGICAL VARIATIONS OF MUSCLE PLANTARIS: ANATOMICAL AND CLINICAL INSIGHT

Address for Correspondence: Dr. Mohini M. Joshi, Associate Professor, Department of Anatomy, Rural Medical College, Pravra Institute of Medical Sciences Loni, Dist. Ahmadnagar Maharashtra, India. Mobile No: +919762601050. E-Mail: atharvamohini@gmail.com Access this Article online Quick Response code Web site: *1 Associate Professor, Department of Anatomy, Rural Medical College, Pravra Institute of Medical Sciences, Loni, Dist.Ahmadnagar Maharashtra, India. 2 Dean, Arbindo Institute of Medical Sciences, Indore, India. 3 Professor and Head, Department of Anatomy, Arbindo Institute of Medical Sciences, Indore, India. Background: Plantaris is the largest muscle in mammals other than primates. Plantaris muscle has been a subject of much confusion and Evolutionists have speculated on its phylogenetic significance, as a vestigial organ, while surgeons have removed it ‘useless vestige’ to employ its tendon as a spare part for the surgical repair. In humans it is reduced greatly in size, power, and function and may even be absent. Aim: With this background the aim of the present work is to study morphology, describe the observed variations of the Plantaris muscle, and to discuss the functional significance of Plantaris muscle. Methodology: For the present work 84 limbs available in the department of Anatomy were dissected. The posterior aspect of the knee was dissected using standard surgical equipment and dissection techniques. The Plantaris muscle was isolated and length of fleshy belly and tendon were measured. Any variations in origin, insertion and size were recorded. Result: Variation in insertion of the Plantaris has observed like insertion along medial margin of tendocalcaneus on to calcaneus, in front of tendocalcaneus on to calcaneus, fused to tendocalcaneus and insertion of the Plantaris on deep fascia of leg at the level of ankle. Other variations noted were two bellies of the Plantaris one from lateral supracondylar ridge and other from deep surface of Gastrocnemius, two heads of Plantaris: Both bellies were fused in the lower part producing bipennate arrangement, thin & thick belly of the Plantaris muscle. Variations also observed in relation to origin that the muscle is originating from deep surface of lateral head of Gastrocnemius & in other case origin from capsule. Bicipital Plantaris was seen where one head was originating from capsule of knee joint and other from lateral condyle. Conclusion: In order to avoid any inadvertent injury during surgical operations, variation of the Plantaris must be borne in mind. Awareness of the insertion pattern of the Plantaris tendon is also important for clinicians in the diagnosis of muscle tears and for surgeons performing reconstructive procedures. Considering the above facts, the existence and importance of the Plantaris muscle cannot be undermined.

Task-dependent inhibition of slow-twitch soleus and excitation of fast-twitch gastrocnemius do not require high movement speed and velocity-dependent sensory feedback.

Although individual heads of triceps surae, soleus (SO) and medial gastrocnemius (MG) muscles, are often considered close functional synergists, previous studies have shown distinct activity patterns between them in some motor behaviors. The goal of this study was to test two hypotheses explaining inhibition of slow SO with respect to fast MG: (1) inhibition occurs at high movement velocities and mediated by velocity-dependent sensory feedback and (2) inhibition depends on the ankle-knee joint moment combination and does not require high movement velocities. The hypotheses were tested by comparing the SO EMG/MG EMG ratio during fast and slow motor behaviors (cat paw shake responses vs. back, straight leg load lifting in humans), which had the same ankle extension-knee flexion moment combination; and during fast and slow behaviors with the ankle extension-knee extension moment combination (human vertical jumping and stance phase of walking in cats and leg load lifting in humans). In addition, SO EMG/MG EMG ratio was determined during cat paw shake responses and walking before and after removal of stretch velocity-dependent sensory feedback by self-reinnervating SO and/or gastrocnemius. We found the ratio SO EMG/MG EMG below 1 (p < 0.05) during fast paw shake responses and slow back load lifting, requiring the ankle extension-knee flexion moment combination; whereas the ratio SO EMG/MG EMG was above 1 (p < 0.05) during fast vertical jumping and slow tasks of walking and leg load lifting, requiring ankle extension-knee extension moments. Removal of velocity-dependent sensory feedback did not affect the SO EMG/MG EMG ratio in cats. We concluded that the relative inhibition of SO does not require high muscle velocities, depends on ankle-knee moment combinations, and is mechanically advantageous for allowing a greater MG contribution to ankle extension and knee flexion moments.

Release of the medial head of the gastrocnemius for Achilles tendinopathy in sedentary patients: a retrospective study.

Our aim was to ascertain whether releasing the medial head of he gastrocnemius improves clinical and functional outcomes of sedentary patients with long-standing tendinopathy of the main body of the Achilles tendon and allows return to daily activities. Eighteen patients (seven men, 11 women) underwent release of the gastrocnemius medial head to manage chronic unilateral Achilles tendinopathy. Pre- and postoperatively, each patient completed the Victorian Institute of Sports Assessment-Achilles tendon (VISA-A) questionnaire. The maximum calf circumference and isometric plantar flexion strength of the gastrocsoleus complex were measured in both the affected and the contralateral leg. Function was scored using the 4-point Boyden scale at the last assessment. At the last appointment, at an average follow-up of 54months, maximum calf circumference and strength of the operated leg were not significantly different than pre-operatively and were significantly lower than the contralateral leg. All patients could satisfactorily perform the same work and daily activities as before symptom onset. At the last follow-up, the average VISA-A score was improved from a preoperative average value of 52.3 to 75 (range 51-94) (p < .001). This approach to managing isolated Achiles tendinopathy is safe, effective, low cost and allows safe return to preinjury daily activities.

The anatomy and clinical application of sural blood vessel combined with free skin flap

Objective To study the anatomical characteristics of sural blood vessel, and to explore the clinical effect of sural blood vessel combined with free skin flap in repairing large tissue defect of calf. Methods 10 fresh adult cadavers were col-lected for experimental studies. Chose 8 cadavers randomly and ligate the sural medial vessel （4 cases） or sural lateral vessel （4 cases） of one limb, leaving the contralateral limb un-ligated as control. Angiography was performed to observe the blood supply of the gastrocnemius muscle after the ligation of the sural medial vessel or sural lateral vessel. For the remaining 2 cadavers, the ori-gin, diameter, and location of the communicating branch of the gastrocnemius muscle were observed by macroscopic anatomy and vascular cast. The data of 19 patients with large tissue defect of calf from October 2006 to September 2013 were analyzed retro-spectively for clinical research. There were 11 males and 8 females aged from 10-40 years （mean, 32 years）. 12 patients took sural medial blood vessels as recipient vessels, and 7 patients took sural lateral blood vessels. 6 patients were grafted with free chest na-vel flaps, 8 with anterolateral thigh flap, 2 with lateral thoracic flap, and 3 with latissimus dorsi flap. The areas of wound surface were ranging from 5 cm×10 cm-8 cm×37 cm. The areas of the flap dissected were ranging from 7 cm×10 cm-10 cm×30 cm. Re-sults The study found that the blood supply of gastrocnemius muscle of the calf was multifocal, and was mainly by sural artery. When the blood supply of sural artery was cut off from one side, the gastrocnemius muscle could be supplied by the communicat-ing branches between medial and lateral head of gastrocnemius muscle and the communicating branches of soleus muscle. The communicating branches were at constant anatomical locations, with larger diameter and rich branches. All the 19 cases of free skin flip transplantation were survived. Healing time of wound was ranging from 13-29 d, among which 11 cases were primary healing, and 8 were secondary healing. The follow-up duration was ranging from 12-24 months. The flaps could endure friction of certain degree. No sensory dysfunction was reported. For the cases that split thick skin graft or split-thickness thin skin flap taken from abdomen or huckle were autografted to cover the donor site, primary healing was all gained. Conclusion The sural blood vessels are deeply located in the gastrocnemius muscle at constant anatomical locations, with a long pedicle and a large diameter, and are easy to be dissected, thus they are suited for anastomosis. Sural vessel combined with free skin flip provides a new treat-ment option for the repair of large tissue defect of calf. Key words: Blood vessels Surgical flaps Transplantation; autologous Leg

Vascular anatomy of the medial sural artery perforator flap: A new classification system of intra-muscular branching patterns

The medial sural artery perforator (MSAP) flap is a versatile fasciocutaneous flap. The main difficulty encountered when raising the MSAP flap is in obtaining adequate pedicle length during intra-muscular dissection. The objective of this study was to determine the pattern of intra-muscular course of the MSAP flap pedicle. 14 cadaveric specimens were dissected and CT angiograms of 84 legs were examined. The intra-muscular branching pattern and depths of the medial sural artery branches were analyzed. The number of perforators, position of the dominant perforator and both intra-muscular and total pedicle length were also recorded and compared to existing anatomical data. Three types of arterial branching pattern were identified within the medial gastrocnemius, demonstrating one (31%), two (59%) or three or more (10%) main branches. A dominant perforator from the medial sural artery was present in 92% of anatomical specimens (13/14). Vertically, the location of the perforator from the popliteal crease was on average 13cm (±2cm). Transversely, the perforator originated 2.5cm (±1cm) from the posterior midline. Using CT angiography it was possible in 10 consecutive patients to identify a more superficial intra-muscular branch and determine the leg with the optimal branching pattern type for flap harvest. This study is the first to describe the variability of the intra-muscular arterial anatomy of the medial head of gastrocnemius muscle. Surgeons utilizing the MSAP flap option should be aware of the possible branching pattern types and consequently the differing perforator distribution and depths of intra-muscular branches. Routine use of pre-operative CT angiogram may help determine which leg has the most favorable branching pattern type and intra-muscular course for flap harvest.