Posterior Calf Muscles Research Articles

Isolated Calf Muscle Venous Thrombosis: A Review of Anticoagulation Strategies.

Deep vein thrombosis (DVT) of the lower extremities is divided into 2 categories according to the extent of thrombosis involvement. Thrombosis involving the popliteal vein, femoral vein, and iliac vein is classified as proximal DVT, while thrombosis involving the anterior tibial vein, posterior tibial vein, peroneal vein, and calf muscles vein is regarded as distal DVT. There are updated guidelines for the anticoagulant treatment for proximal DVT, but the best anticoagulant treatment for distal DVT is still controversial, especially for isolated calf muscular vein thrombosis (CMVT). The risk of isolated CMVT extending to the proximal deep veins and developing into pulmonary embolism is lower than with distal DVT. Some scholars believe that isolated CMVT has the risk of evolving into proximal deep vein thrombosis and pulmonary embolism, and active early anticoagulation therapy can reduce the risk and benefit patients. In addition, based on the characteristics of CMVT and the bleeding risk of anticoagulation therapy, some studies have recommended use of non-anticoagulation methods such as compression therapy. There is still a lack of multicenter, big-data, randomized, controlled trials on the benefits or risks of anticoagulation therapy. Among scholars who support anticoagulation therapy, there is still a lack of consensus on the optimal duration. This article reviews the current evidence on anticoagulant therapy for patients with isolated CMVT and how long the anticoagulation course should be if anticoagulation is required. Our research will provide a theoretical basis for subsequent research. More prospective studies with larger sample sizes are needed to provide more clinical evidence.

Whole-Body Muscle Magnetic Resonance Imaging in 81 Patients with Spinal and Bulbar Muscular Atrophy: A Prospective Study.

Spinal and bulbar muscular atrophy (SBMA) is characterized by slow, progressive bulbar and limb muscle weakness; however, the pattern of progression of muscle fat infiltration remains unclear. We assessed the progression of muscle involvement in 81 patients with SBMA using whole-body muscle magnetic resonance imaging (MRI), alongside clinical and laboratory findings. This prospective study included patients with genetically confirmed SBMA who underwent whole-body muscle MRI. We analyzed muscle fat infiltration and the pattern of involved muscles using cluster analysis, visualizing the sequential progression of fat infiltration. Muscle clusters demonstrated correlation with clinical scales and laboratory findings. Additionally, linear regression analysis was performed to identify the MRI section most strongly associated with 6-minute walk test (6MWT). We included 81 patients with SBMA (age = 54.3 years). After categorizing the patients into 6 clusters based on the pattern of muscle fat infiltration, we observed that muscle involvement began in the posterior calf and progressed to the posterior thigh, pelvis, trunk, anterior thigh, medial thigh, anterior calf, and upper extremity muscles. These muscle clusters correlated significantly with disease duration (τ = 0.47, p < 0.001), 6MWT (τ = -0.49, p < 0.001), and serum creatinine level (τ = -0.46, p < 0.001). The whole-body MRI indicated the thigh as the section most significantly correlated with 6MWT. We used whole-body muscle MRI to determine the sequential progression of the fat infiltration in SBMA. Our findings may enable the identification of objective and reliable imaging outcome measures in the study of the natural history or future clinical trials of SBMA. ANN NEUROL 2024;95:596-606.

Shape estimation of flexible ultrasound arrays using spatial coherence: A preliminary study

A flexible ultrasound array can potentially provide a larger field-of-view, enhanced imaging resolution, and less operator dependency compared to conventional rigid transducer arrays. However, such transducer arrays require information about relative element positions for beamforming and reconstructing geometrically accurate sonograms. In this study, we assess the potential utility of using spatial coherence of backscattered radiofrequency data to estimate transducer array shape (inverse problem). The methodology is evaluated through 1) simulation of flexible arrays and 2) blinded in vivo experiments using commercial rigid transducer arrays on various anatomical targets (shoulder, forearm, scapular, posterior calf muscles, and abdomen) and multi-purpose ultrasound phantoms. The average Euclidean error of shape estimation is below 0.1 wavelengths for simulated arrays and below 1.4 wavelengths (median: 0.58 wavelengths) for real arrays. The complex wavelet structural similarity index between the B-mode images reconstructed with estimated and ground truth array shapes is above 99 % and 96 %, for simulations and experiments, respectively. These findings suggest that optimizing for spatial coherence may be an effective way to estimate the unknown shape of conformal ultrasound arrays.

Comparison of Structural Diagnosis and Management (SDM) approach and MyoFascial Release (MFR) for improving plantar heel pain, ankle range of motion and disability: A randomized clinical trial

ABSTRACT [Purpose] The purpose of this study was to compare the effectiveness of the Structural Diagnosis and Management (SDM) approach with Myofascial Release (MFR) in improving plantar heel pain, ankle range of motion, and disability. [Subjects] Sixty-four subjects, aged 30–60 years, with a diagnosis of plantar heel pain, plantar fasciitis, or calcaneal spur by a physician according to ICD-10, were equally allocated to the MFR (n = 32) and SDM (n = 32) groups by hospital randomization and concealed allocation. [Methods] In this assessor-blinded randomized clinical trial, the control group performed MFR to the plantar surface of the foot, triceps surae, and deep posterior compartment calf muscles, while the experimental group performed a multimodal approach utilizing the SDM concept for 12 sessions over 4 weeks. Both groups also received strengthening exercises, ice compression, and ultrasound therapy. Pain, activity limitations and disability were assessed as primary outcomes using the Foot Function Index (FFI) and Range of motion (ROM) assessment of the ankle dorsiflexors and plantar flexors using a universal goniometer. Secondary outcomes were measured using the Foot Ankle Disability Index (FADI) and a 10-point manual muscle testing process for the ankle dorsiflexors and plantar flexors. [Results] Both MFR and SDM groups exhibited significant improvements from baseline in all outcome variables, including pain, activity level, disability, range of motion, and function after the 12-week intervention period (p < .05). The SDM group showed more improvements than MFR for FFI pain (p < .01), FFI activity (p < .01), FFI (p < .01) and FADI (p = <.01). [Conclusion] Both MFR and SDM approaches are effective in reducing pain, improving function, ankle range of motion, and reducing disability in plantar heel pain, however, the SDM approach may be a preferred treatment option.

Effect of vitamin K2 in the treatment of nocturnal leg cramps in the older population: Study protocol of a randomized, double-blind, controlled trial.

Nocturnal leg cramps (NLCs) are sudden contractions of the leg muscles, usually in the posterior calf muscles at night, affecting sleep quality. Because the precise pathophysiology of NCLs is unclear, different interventions have been proposed. There is conflicting evidence regarding the efficacy of conventional interventions in preventing cramps. Thus, the present study aims to investigate the effects of vitamin K2 for NLCs in a prospective randomized, double-blind, controlled trial. This multicenter, randomized, double-blind, placebo-controlled clinical study will enroll older age (≥65-year-old) with two or more documented episodes of NLCs during 2 weeks of screening. Participants will be randomized to receive vitamin K2 or a similar-looking placebo for 8 weeks in a 1:1 ratio. Follow-up visits will be scheduled each week at the beginning of 4-week intervention, then participants will be visited semimonthly. The primary outcome is the difference in the mean number of NLCs per week in the vitamin K2 and placebo arms. The secondary outcomes include the severity and duration of NLCs in the vitamin K2 and placebo arms. Two hundred patients will be needed, for this two-treatment parallel design study, to achieve a probability is 90% that the study will detect a treatment difference at a two-sided 0.04 significance level, if the difference between treatments is 3.6 (difference in means between treatment arms) NLC events. Nocturnal Leg Cramps (NLCs) are a common musculoskeletal disorder in the general population, but effective and safe interventions have not been established. Our previous study has shown vitamin K2 was effective to reduce the frequency, severity, and duration of dialysis-related muscle cramps with a good safety profile. This randomized controlled trial (RCT) of rigorous methodological design will help to establish the effectiveness of vitamin K2 for the management of NLCs in older population. The findings of this RCT will encourage the studies of vitamin K2 in musculoskeletal disorders. www.ClinicalTrials.gov, identifier, NCT05547750.

Contribution of lower extremity muscles to center of mass acceleration during walking: Effect of body weight

Overweight or obesity is known to be associated with altered activations of lower extremity muscles. Such changes in muscular function may lead to the development of mobility impairments or joint diseases. However, little is known about how individual lower extremity muscles contribute to the whole-body center of mass (COM) control during walking and the effect of body weight. This study examined the contribution of individual lower extremity muscle force to the COM accelerations during walking in overweight and non-overweight individuals. Musculoskeletal simulations were performed for the stance phase of walking with data collected from 11 overweight and 13 non-overweight adults to estimate lower extremity muscle forces and their contributions to the COM acceleration. Mean time-series data from each parameter were compared between body size groups using Statistical Parametric Mapping. Compared to the non-overweight group, the overweight group revealed a greater gastrocnemius contribution to the mediolateral (p = 0.006) and vertical (p < 0.001) COM accelerations during mid-stance, and had a lower vastus contribution to the anteroposterior COM acceleration (p < 0.001) during pre-swing. Increased contributions from the large posterior calf muscles to the mediolateral COM acceleration may be related to efforts to alleviate COM sway in overweight individuals.

Muscle volume evaluation using 3DCT for congenital clubfoot.

BackgroundIn congenital clubfoot, the lower leg is very thin and the calf muscles are hypoplasic. However, there are few studies reporting real muscle volume.PurposeThe purpose of this study is to assay the muscle volume in congenital clubfoot using 3DCT and to quantify the degree of the hypoplasia.Material and methodsFrom January 2015 to December 2016, nine consecutive patients, seven male and two female, with unilateral congenital clubfeet were recruited for CT scans. Axial transverse sectional CT scans were acquired from the delineation of the fibular head to the tibial plafond. From the data, we rendered the entire muscle in 3D for muscle volume assay, and further segmented the posterior musculature for comparison between the normal and affected sides.ResultsThe whole muscle volume on the normal side was 291.23 cm3 (181.23–593.49) and that on the affected side was 225.08 cm3 (120.71–429.08), for an affected side to normal side ratio of 0.79 (0.72–0.9), which was significantly smaller (p < .01). Posterior muscle volume on the normal side was 175.81 cm3 (103.72–376.32) and that on the affected side was 106.52 cm3 (58.3–188.39). The ratio of posterior muscle to whole muscle on the normal side was 0.62 (0.46–0.75), and that on the affected side was 0.48 (0.4–0.55), such that the affected side was significantly smaller (p < .01)ConclusionThis study contributes quantitative data supporting the longstanding observations that the posterior calf muscles are significantly smaller on the affected side compared to the normal side in congenital clubfoot, and further underscores the importance of the extending the excursion of these muscles.

Effect of dynamic tape on postural sway in individuals with chronic ankle instability

ObjectiveTo examine the effects of dynamic tape on balance control in subjects with chronic ankle instability (CAI). MethodsThis two group experimental pre- and post-treatment design included 18 individuals with CAI and 18 controls. The single-limb stance test with eyes open and closed, standing on a force plate (Accusway Plus; AMTI) for 30 s, was conducted before, 10 min (T1) and 24 h (T24) after a dynamic tape application over the gastrocnemius muscle. Outcome measurements were: mean sway velocity, sway area (circular area), and standard deviation of the body center of pressure path length in both mediolateral and anteroposterior directions. Individuals with poor (unable to perform a single leg test for at least 30 s, eyes closed) vs. good postural stability, were also compared. ResultsIn both groups, a repeated analysis of variance demonstrated a significant time main effect on sway velocity (F = 14.95; p < 0.001) and path length (F = 14.95; p < 0.001) during eyes closed. Post-hoc analysis revealed a significant decrease in T1 values compared to baseline. When comparing individuals with poor vs good stability amongst the CAI group, a statistically significant interaction was observed between group, time on sway velocity and path length (F = 3.92; p < 0.05) during eyes closed. In the poor postural group, most T1 values were significantly lower than baseline. ConclusionsDynamic tape when applied to posterior calf muscles, enhanced balance control with no difference between CAI individuals and controls. The contribution of the tape was greater in those with poor postural stability.

Efficiency of mesenchymal stromal cells (MSCs) in the treatment of patients with critical limb-threatening ischemia

Relevance. The relevance of the study is determined by the fact that hopes are placed in the cell therapy for patients with critical limb-threatening (CLI) ischemia as a method of the restoration of blood circulation in the affected limb in patients who cannot undergo surgical or endovascular intervention. Aim. To evaluate the efficiency of allogeneic MSCs for the treatment of critical lower limb ischemia (randomized placebo-controlled study).Materials and methods. The study included 34 patients with critical lower limb ischemia (grade 4 according to Pokrovsky). There were 18 patients in the MSC group, and 16 patients in the placebo group). The groups were comparable concerning age, disease duration, and comorbidities. Allogeneic MSCs (phenotype CD73+, CD90+, CD105+, CD45–, CD34–, CD14–) were injected into the posterior calf muscles. Clinical outcome, ankle pressure, transcutaneous oxygen tension (tcpO2), and pain-free walking distance (PFWD) were evaluated. The patients were followed-up for 12–36 months. According to the clinical outcome in each group, the patients were divided into subgroups with «effect (+)» or «effect (–)». In 2 patients, there was an «uncertain clinical outcome». When analyzing the results, these patients were assigned to one or another subgroup.Results. In the MSC and placebo groups, the clinical outcome assessed as «effect (+)» or «effect (–)» did not differ (OR 1.5; 95 % CI 0.34–6.7). With different variants of group formation and with the assignment of patients with an «uncertain clinical outcome» to a one or another subgroup, the final results neither differed. According to instrumental research methods (PFWD, tcpO2, ankle pressure, angiography), there were no differences in the MSC and placebo groups. Conclusion. With different variants of analysis and group formation, no convincing evidence that allogeneic MSCs can be effective for the treatment of critical lower limb ischemia have been obtained.

Effects of Short-Term Limitation of Movement of the First Metatarsophalangeal Joint on the Biomechanics of the Ipsilateral Hip, Knee, and Ankle Joints During Walking.

BackgroundWe analyzed the effect of limitation of movement of the first metatarsophalangeal joint (FMJ) on the biomechanics of the lower limbs during walking.Material/MethodsEight healthy college students completed walking under barefoot (BF) and FMJ constraint (FMJC) conditions. We synchronously collected kinematics and dynamics data, and calculated the torque, power, and work of hip, knee, and ankle joints.ResultsCompared with normal conditions, when the FMJ is restricted from walking, the maximum ankle dorsiflexion angle is significantly increased (P<0.001), the maximum plantar flexion angle is significantly reduced (P<0.001), the maximum plantar flexion torque (P<0.001) and the maximum dorsiflexion torque (P<0.05) increased significantly, the maximum power increased significantly (P<0.001), the minimum power decreased significantly (P<0.001), and the negative work increased significantly (P<0.001). The torque of hip and knee joints increased significantly (P<0.05).ConclusionsAfter the movement of the FMJ is restricted, the human body mainly compensates and transfers compensation by increasing the angle of dorsiflexion, increasing work and the activity level of surrounding muscles through the ankle joint, thereby increasing the torque load of the knee and hip joints to maintain the dynamic balance of kinematics. FMJC condition increases the energy consumption of the human ankle, knee, and hip joints during walking. The load is compensated by the gradual attenuation of the ankle, knee, and hip. Long-term limitation may cause damage to the posterior calf muscles and increase the incidence of knee arthritis.

Rodent model of disuse-induced bone loss by hind limb injection with botulinum toxin A

Bone loss materializes rapidly after immobilization or mechanical unloading. Hind limb injection with botulinum toxin A (BTX) is a highly reproducible animal model for disuse-induced bone loss. Here we describe an easy-to-use and enhanced version of the method employing multiple hind limb injections with BTX to induce a pervasive muscle paralysis and thereby disuse of the hind limb. Thirty-six 12–14-week-old female Wistar rats were stratified into three groups: Baseline (Base), Control (Ctrl), and BTX. Disuse was achieved by injecting BTX directly into the right quadriceps femoris muscle, the hamstring muscles, and the posterior calf muscles. The rats were sacrificed after six weeks, and the right rectus femoris muscle and femur were isolated and analyzed. Hind limb disuse resulted in a significant and substantial loss of both muscle mass and bone mass. The loss of bone mass was accompanied by a reduction of trabecular bone mass and a deterioration of the trabecular micro-architecture with a reduction of trabecular thickness and trabecular number compared to Ctrl. In addition, the trabeculae changed from a more plate-like towards a more rod-like shape as indicated by an increase in the structure model index.•Multiple injections with BTX targeting muscles on both the anterior and posterior thigh and the calf ensure a uniform and pervasive muscle paralysis and hind limb disuse.•Hind limb injections with BTX results in a substantial loss of muscle and bone mass and deterioration of the trabecular micro-architecture.•The induction of hind limb disuse with BTX is highly reproducible.

A pilot study assessing T1-weighted muscle MRI in amyotrophic lateral sclerosis (ALS).

The authors set out to study the role of T1-weighted muscle MRI in the diagnostic phase of ALS, comparing images from ten patients and nine age-matched healthy controls (HCs). All subjects underwent MRI of 68 muscles in the hands, paraspinal regions and lower limbs; the images were semi-quantitatively scored. Atrophy was more frequent in muscles of ALS patients than HCs (p < 0.0001); fatty infiltration was particularly marked in iliopsoas (p = 0.046), anterior (p = 0.020) and posterior (p = 0.047) calf muscles in patients. A trend towards agreement was found between MRI and clinic-EMG data for the first dorsal interosseous, paraspinal, and tibial anterior muscles. Muscle T1-weighted MRI can distinguish ALS patients from HCs for specific regions (i.e., legs). MRI abnormalities could be found in pauci-symptomatic spinal muscles in bulbar-onset patients. Muscle MRI may be a useful diagnostic tool in ALS, in particular for muscles difficult to investigate using clinical-EMG methods.

Proton-decoupled carbon magnetic resonance spectroscopy in human calf muscles at 7 T using a multi-channel radiofrequency coil

13C magnetic resonance spectroscopy is a viable, non-invasive method to study cell metabolism in skeletal muscles. However, MR sensitivity of 13C is inherently low, which can be overcome by applying a higher static magnetic field strength together with radiofrequency coil arrays instead of single loop coils or large volume coils, and 1H decoupling, which leads to a simplified spectral pattern. 1H-decoupled 13C-MRS requires RF coils which support both, 1H and 13C, Larmor frequencies with sufficient electromagnetic isolation between the pathways of the two frequencies. We present the development, evaluation, and first in vivo measurement with a 7 T 3-channel 13C and 4-channel 1H transceiver array optimized for 1H-decoupled 13C-MRS in the posterior human calf muscles. To ensure minimal cross-coupling between 13C and 1H arrays, several strategies were combined: mutual magnetic flux was minimized by coil geometry, two LCC traps were inserted into each 13C element, and band-pass and low-pass filters were integrated along the signal pathways. The developed coil array was successfully tested in phantom and in vivo MR experiments, showing a simplified spectral pattern and increase in signal-to-noise ratio of approximately a factor 2 between non-decoupled and 1H-decoupled spectra in a glucose phantom and the human calf muscle.

Acute Effect of 2 Self-Myofascial Release Protocols on Hip and Ankle Range of Motion.

Self-myofascial release (SMR) is an intervention popularly used by rehabilitation, fitness, and sports professionals to improve recovery and performance. In SMR, the athlete/patient applies pressure to the muscle and fascia using various tools, such as balls, rods, foam rolls, and massagers. This study aimed to evaluate the acute effect of 2 SMR protocols (short term and long term) of the posterior thigh and calf muscles on hip and ankle range of motion (ROM) in physically active men. A total of 14 adult males (24.9 [3.2]y, 77.2 [13.2]kg, and 1.75 [0.06]m) who exercise regularly (at least twice a week, 45min per session) participated in this study. Participants performed a short-term SMR protocol (2 × 10 repetitions, SSMR) and a long-term SMR protocol (2 × 20 repetitions, LSMR) of the posterior thigh (using a foam roller) and calf (using a massage stick) muscles in counterbalanced order, on 2 different days with a 48-hour interval. Ankle dorsiflexion and hip-flexion ROM, evaluated at 5 moments: pre- and post-SSMR, pre- and post-LSMR, and in the control condition, which was always performed at the first visit. The SMR promoted significant gains for both dorsiflexion (F1,13 =202.67, P < .001, ) and hip flexion (F1,13 = 66.46, P < .001, ), regardless of the protocol and limb analyzed. The average increase for both limbs corresponded, approximately, to 11% for ankle dorsiflexion and to 6% for and in hip flexion. The results suggest that SMR of the posterior thigh and calf muscles acutely increases the ROM of both hip flexion and ankle dorsiflexion and that duplicating the SMR volume from 10 to 20 repetitions per set seems not to promote additional gains.

Musculotendinous Disorders in the Lower Leg.

AbstractMusculotendinous injury in the lower leg is associated with a variety of athletic activities. Myotendinous strain is typically localized to the posterior calf muscles, with involvement of the medial head of gastrocnemius muscle most common. Nontraumatic soft tissue injuries of the lower leg, including muscle herniation, are less frequently imaged. Ruptured popliteal cysts and deep vein thrombosis are important differential considerations in the patient presenting with acute calf pain and swelling.

Hyperckemia and myalgia are common presentations of anoctamin-5-related myopathy in French patients.

Patients with anoctamin-5 (ANO5) mutations may present not only with limb-girdle muscular dystrophy type 2L or adult-onset Miyoshi-type myopathy but also with asymptomatic hyperCKemia, exercise intolerance, or rhabdomyolysis. Data from 38 patients in France with ANO5 mutations with and without muscle weakness on first examination were compared. Twenty patients presented without muscle weakness. Median age at symptom onset or discovery of hyperCKemia was 23 years. Creatine kinase levels ranged from 200 to 40,000 U/L. Electromyography showed a myopathic pattern in 5 patients, and muscle imaging showed involvement of posterior calf muscles in 10 patients. Mild cardiac involvement was observed in 2 patients. Sixteen patients remain free of weakness after a median follow-up period of 5 years. Asymptomatic, sometimes mild hyperCKemia or exercise intolerance is a presentation of ANO5-related myopathy and may remain isolated or precede muscle weakness by many years. Muscle Nerve 56: 1096-1100, 2017.

1. Fashion victim: Rhabdomyolysis and bilateral peroneal and tibial neuropathies as a result of squatting in skinny jeans

A 35 year old woman presented with bilateral foot drop and numbness following repetitive squatting while wearing “skinny” jeans. Her examination demonstrated bilateral, severe, global weakness of ankle and toe movements, somewhat more marked on the right, absent ankle jerks and impaired sensation over the lateral aspects of both lower legs and the dorsum and soles of both feet. Her lower limbs were markedly oedematous and the jeans had to be cut off for removal. Investigations showed a creatine kinase level of 73215 IU/L with normal renal function. CT scan of the lower limbs demonstrated myonecrosis in the posterior calf muscles. Nerve conduction studies showed bilateral conduction block between the popliteal fossa and fibular head of the common peroneal nerves. Compound muscle action potential amplitudes of the tibial nerves were also diminished with stimulation in the popliteal fossa, compared with the ankle. The sural and superficial peroneal sensory responses were normal but the right medial plantar SAP was absent and the left medial plantar SAP was markedly reduced in amplitude. With conservative therapy, the patient’s oedema and neurological function improved and she was discharged after regaining independence with her mobility four days later. We postulate that the patient’s peroneal neuropathies were the result of compression between the biceps femoris tendon and fibular head as a result of squatting while the tibial neuropathies were likely caused by compression of the nerves in the posterior compartment of the calf by oedematous muscles which had undergone ischaemic myonecrosis as a result of squatting. The wearing of “skinny” jeans had likely potentiated the tibial neuropathies by causing a compartment syndrome as the lower legs swelled.

Deep massage to posterior calf muscles in combination with neural mobilization exercises as a treatment for heel pain

Deep massage to posterior calf muscles in combination with neural mobilization exercises as a treatment for heel pain

Relevance and reproducibility of three clinical tests in weight-bearing for chronic plantar heel pain syndrome

Conclusion(s): Data indicated that both treatment protocols resulted in an overall short-term improvement, however, DMS treatment was significantly more effective in treating PHPS than USS treatment. Further research is recommended to assess and validate this approach, and its rationale, for treatment of PHPS. Implications: This study introduces an easily implemented, novel treatment protocol for physiotherapeutic intervention in individuals with PHPS. The deep massage therapy to posterior calf muscles combined with stretching exercises was shown as an effective treatment in providing improvement of function and relief of pain.

Low grade malignant schwannoma of tibial nerve

The aim of this paper is to report a rare case of a sizeable low grade malignant schwannoma of the posterior tibial nerve and to underline the method of treatement. A 37-year-old white male presented himself with a slowly growing mass in his left calf. According to the slower rate of growing and to the mobility of the tumor diagnosis was oriented to a benign lesion of posterior calf muscles. The decision was to perform a excisional biopsy of the tumor. The examined tumor was classified as low-grade malignant peripheral nerve sheath tumor. We did not have a suspicion of malignancy in our case due to the slowly growing rate. The treatment performed was surgical excision of the tumor with adequate exposure of normal nerve proximally and distally. Clinical and imagistic findings of this case suggested a benign tumor. According to this, the decision was to perform a excisional biopsy of the tumoral mass and not only a biopsy first.