The tendon of the fibularis brevis muscle - Systematic overview and new classification system.

The fibularis brevis muscle belongs to the lateral compartment of the leg. It originates from the lower two-thirds of the lateral surface of the fibula bone and it also is attached to the anterior intermuscular septum. Its insertion is normally located on the tuberosity at the base of the fifth metatarsal bone, on its lateral side. However, distal attachment of this muscle is morphologically variable. Different variations have been identified and some classification systems have been created for both adults and foetuses. Based on various literature references, we have created a new classification system and compared the frequency of each type. The main aim of this review is to present morphological variations of the fibularis brevis tendon with their clinical significance, especially in autografting in case of surgical treatment of fibularis brevis tendon rupture. The clinical aspect of this pathology and some medical cases will also be presented.

Peroneus tertius revisited: The morphological variability of the bifurcated peroneus tertius insertion - An anatomical study.

BACKGROUND: The peroneus tertius muscle (PT) is one of the extensor muscles of the lower leg, often described as a variable separation from the extensor digitorum longus muscle (EDL). According to literature it has six different types of insertion, one of them (Olewnik Type IV) having two tendons inserting to the fifth metatarsal bone (FMTB). Morphometric data about this type of insertion is sparse, especially the relation between the two tendons, albeit the PT is suspected to contribute to stress fractures of the FMTB. Therefore, we examined this type of insertion to give detailed information on the tendons, the insertion points and the respective relations. METHODS: We examined 27 lower extremities of embalmed human bodies (12 paired, 15 single sided; 12 right and 15 left) with a distinguishable PT with two tendons inserting to the FMTB (Olewnik IV). The specimens were obtained of an undergrad dissection program, which in turn obtained them from a body donation program. After dissection of the PT and photo documentation in situ, resection and measurement of morphological properties of the tendons were performed with the PT attached to the fifth metatarsal bone. RESULTS: Results of the respective measurements yielded a wide range of variation, especially in the insertion point of the anterior tendon on the fifth metatarsal and the relation between the two tendons, but with no significant difference between sides or sex, except for the length of the posterior tendon between sex. The distance between the base of the FMTB and posterior tendon varies from 0 to 9 mm, with one outlier at 24 mm (mean = 3.9 ± 4.8 mm), the distance between the insertions from 0 to 15 mm (mean = 4.7 ± 4.7 mm), resulting in how far of the FMTB the anterior tendon reaches varying from 17 to 60 mm (mean = 39.6 ± 11.5 mm) or 22-98% (mean = 64 ± 19%). CONCLUSION: Our findings give a detailed overview of the morphological features the PTT can have, when attached with two tendons to the FMTB. Especially the varying relationship between those two insertions and varying point of the anterior insertion are of interest, as they might support its complex role in the occurrence of fractures of the fifth metatarsal by providing different amounts of torsional stress and its tendons can be used as tendon-grafts.

Anatomical patterns of the sural nerve: a meta-analysis with clinical and surgical considerations.

BACKGROUND: The sural nerve (SN) supplies the posterolateral aspect of the leg and the lateral aspects of the ankle and foot and descends through the gastrocnemius muscle along the lower third of leg. Because in-depth knowledge about SN anatomy is essential for clinical and surgical approaches, our study aims to review SN anatomical patterns. METHODS: We searched the PubMed, Lilacs, Web of Science, and SpringerLink databases to find relevant articles for meta-analysis. We assessed the quality of the studies using the Anatomical Quality Assessment tool. We used proportion meta-analysis to analyze the SN morphological variables and simple mean meta-analysis to analyze the SN morphometric variables (nerve length and distance to anatomical landmarks). RESULTS: Thirty-six studies comprised this meta-analysis. Overall, Type 2A (63.68% [95% CI 42.36-82.64]), Type 1A (51.17% [95% CI 33.16-69.04]) and Type 1B (32.19% [95% CI 17.83-48.38]) were the most common SN formation patterns. The lower third of leg (42.40% [95% CI 32.24-52.86]) and middle third of leg (40.00% [95% CI 25.21-53.48]) were the most common SN formation sites. The pooled SN length from nerve formation to the lateral malleolus was 144.54 mm (95% CI 123.23-169.53) in adults, whereas the SN length was 25.10 mm (95% CI 23.20-27.16) in fetuses in the second trimester of gestation and 34.88 mm (95% CI 32.86-37.02) in fetuses in the third trimester of gestation. CONCLUSIONS: The most prevalent SN formation pattern was the union of the medial sural cutaneous nerve with the lateral sural cutaneous nerve. We found differences regarding geographical subgroup and subject age. The most common SN formation sites were the lower and middle thirds of the leg.

Association between calf circumference and incontinence in Chinese elderly.

BACKGROUND: The objective of this study was to analyze the association between calf circumference and incontinence in Chinese elderly, and to find out the maximal cut-off point by gender for the use of calf circumference in screening for incontinence. METHODS: In this study, participants were from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS). The maximal calf circumference cut-off point and other incontinence-related risk factors were explored using receiver operating characteristic (ROC) curves and logistic regression analysis. RESULTS: The study included 14,989 elderly people (6,516 males and 8,473 females) over 60. The prevalence of incontinence in elderly males was 5.23% (341/6,516), significantly lower than females, which was 8.31% (704/8,473) (p < 0.001). There was no correlation between calf circumference < 34 cm in males and < 33 cm in females and incontinence after adjusting the confounders. We further stratified by gender to predict incontinence in elderly based on the Youden index of ROC curves. We found the association between calf circumference and incontinence was the strongest when the cut-off points were < 28.5 cm for males and < 26.5 cm for females, with an odds rate (OR) value of 1.620 (male, 95%CI: 1.197-2.288) and 1.292 (female, 95%CI: 1.044-1.600) after adjusting the covariates, respectively. CONCLUSIONS: Our study suggests that calf circumference < 28.5 cm in males and < 26.5 cm in females is a risk factor for incontinence in the Chinese elderly population. Calf circumference should be measured in routine physical examination, and timely interventions should be made to reduce the risk of incontinence in subjects with calf circumference less than the threshold.

The Lower Limbs of Sprinters Have Larger Relative Mass But Not Larger Normalized Moment of Inertia than Controls.

PURPOSE: Sprinters exhibit inhomogeneous muscularity corresponding to musculoskeletal demand for sprinting execution. An inhomogeneous morphology would affect the mass distribution, which in turn may affect the mechanical difficulty in moving from an inertia perspective; however, the morphological characteristics of sprinters from the inertia perspective have not been examined. Here we show no corresponding differences in the normalized mass and normalized moment of inertia between the sprinters and untrained nonsprinters. METHODS: We analyzed fat- and water-separated magnetic resonance images from the lower limbs of 11 male sprinters (100 m best time of 10.44-10.83 s) and 12 untrained nonsprinters. We calculated the inertial properties by identifying the tissue of each voxel and combining the literature values for each tissue density. RESULTS: The lower-limb relative mass was significantly larger in sprinters (18.7% ± 0.7% body mass) than in nonsprinters (17.6% ± 0.6% body mass), whereas the normalized moment of inertia of the lower limb around the hip in the anatomical position was not significantly different (0.044 ± 0.002 vs 0.042 ± 0.002 [a. u.]). The thigh relative mass in sprinters (12.9% ± 0.4% body mass) was significantly larger than that in nonsprinters (11.9% ± 0.4% body mass), whereas the shank and foot relative masses were not significantly different. CONCLUSIONS: We revealed that the mechanical difficulty in swinging the lower limb is not relatively larger in sprinters in terms of inertia, even though the lower-limb mass is larger, reflecting their muscularity. We provide practical implications that sprinters can train without paying close attention to the increase in lower-limb mass and moment of inertia.

Calf circumference change and all-cause mortality among community-dwelling Chinese older people.

BACKGROUND: Previous studies have described an association between single time point calf circumference (CC) and mortality. Evidence of associations between CC change and mortality is lacking. We aimed to determine the relationship between the CC change over time and all-cause mortality. METHODS: We conducted a retrospective cohort study of 906 participants in the 2014-2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS). Restricted cubic splines were used to analyze associations between the relative CC change (exposure) and all-cause mortality (primary outcome). When there was evidence of non-linearity, a piecewise Cox regression model was next fitted, adjusting for sociodemographic characteristics, health behaviours, health status and baseline CC. RESULTS: The mean (SD) age was 83.8 (12.2) years old, and 50.2% (455/906) of participants were male. We observed a U-shaped association between the relative CC change (%) and all-cause mortality (P for non-linearity <0.001). Participants with stable CC over time had the lowest risk of death. After adjusting for covariates, when CC decreased over time, the hazard ratio per 10% higher in CC change was 1.32 (1.01-1.69). When CC increased over time, the hazard ratio per 10% higher in CC change was 1.35 (1.10-1.66). CONCLUSION: Stable CC over time was associated with the lowest mortality risk. Our findings indicate the practical significance of monitoring CC change in older adult.

Clinical and variational evaluation of peroneus tertius muscle.

This research was conducted to define the typology of the peroneus tertius, which is considered to be a part of the musculus extensor digitorum muscle and plays a role in dorsiflexion and eversion of the foot. In addition, another aim of the study was to examine the relationship of the peroneus tertius with the extensor digitorum longus and to investigate the possible effects of the tendon/insertio properties of the peroneus tertius on the fifth metatarsal. In this study; classical anatomical dissection was performed on 30 lower limbs. In this study, various parameters related to muscle origin, insertion, tendon and muscle dimensions were measured. It has been found that PTM was absent in 26.6% of the specimens and in 23.3% (n = 7) of the cases PTM was directly originated from the EDL. In 56.7% of the specimens (n = 17), the PTM tendon was mutually inserted into the dorsomedial surface of the 5th metatarsal and dorsolateral of the 4th metatarsal, while in 10.0% of the specimens it has thin medial bands (2 × 1 mm) towards the 5th digit. At the end of the study, the PTM origin was categorized into three different types and PTM insertion was categorized into five different types. Variation of PTM, muscle morphology and tendon diameter are extremely important in terms of minimally invasive surgical technique. Since the accessory tendon must have the properties close to the tendon that will be replaced, we believe that the results of our research provide unique useful information to clinicians. This study is the cadaver research.

Fast NURBS-based parametric modeling of human calves with high-accuracy for personalized design of graduated compression stockings.

BACKGROUND AND OBJECTIVES: Accurate human body models are increasingly demanded by high-quality human-centered ergonomic applications, especially the design and manufacturing of compressive functional apparels. However, existing parametric models in related works are not capable to accurately describe detailed local shape features of human. METHODS: In this work, a high-accuracy parametric modeling approach for human limb was proposed. 3D Scans of human calves were studied. Key data points of the scanned human calves were identified according to human anatomy, forming a quasi-triangular mesh of feature points. Then, non-uniform rational B-splines (NURBS) method was implemented. Control points were calculated from the key data points, with which the human calf shapes can be reconstructed by the smooth NURBS surface, giving rise to a new parametric model of human calves. Error between the scanned and reconstructed calf shapes were analyzed to verify the effectiveness of this model. RESULTS: Error analysis showed that, this proposed method delivers a high-efficiency and high-accuracy parametric shape modeling approach with averaged error observed as only 0.37% for all the 260 subjects, much less compared to previous relative works (around 5%). For tentative application, customized medical compression stockings were designed based on this model and proved as valid to exert desired gradient compression on the according calf mannequin. CONCLUSIONS: By introducing the non-uniform rational B-splines method, a parametric model capable of characterizing human limbs with high-accuracy was proposed. Using very small amount of data, this model is expected to highly facilitate remote customized design and provide 3D shape references for design of compressive garments. Moreover, the proposed methods can inspire developments of other mixed modeling methods for high-accuracy applications.

Comparison of the soleus and plantaris muscles in humans and other primates: Macroscopic neuromuscular anatomy and evolutionary significance.

In humans, the soleus is more developed compared to other primates and has a unique architecture composed of anterior bipennate and posterior unipennate parts, which are innervated by different nerve branches. The anterior part of the human soleus was proposed to be important for bipedalism, however, the phylogenetic process resulting in its acquisition remains unclear. Providing insights into this process, the anterior part of the soleus was suggested to be closely related to the plantaris based on the branching pattern of their nerve fascicles. To reveal the phylogeny of the soleus and plantaris in primates, the innervation patterns of the posterior crural muscles were compared among a wide range of species. From their branching pattern, posterior crural muscles could be classified into superficial and deep muscle groups. The anterior part of the soleus and plantaris both belonged to the deep muscle group. In all the examined specimens of ring-tailed lemurs and chimpanzees, as well as in one out of two specimens of siamang, the nerve branches corresponding to those innervating the anterior part of the human soleus were found. The muscular branches innervating the anterior part of the soleus and plantaris formed a common trunk or were connected in all the specimens. These results indicate that the anterior part of the soleus is closely related to the plantaris across different species of primates. In turn, this suggests that the anterior part of the soleus is maintained among primates, and especially in humans, where it develops as the characteristic bipennate structure.

The morphological variability of fibularis tertius origin in human foetuses.

BACKGROUND: The purpose of this study was to characterize the morphology of the fibularis tertius (FT) in human fetuses, and to provide a classification based on its modes of origin in human fetuses. METHODS: The material comprised 100extremities from 50 spontaneously aborted human fetuses (19 male, 31 female, 100 lowerlimbs in total), aged 18-38 weeks of gestation. These were dissected and the presence or absence of the FT muscle as well as the type of its proximal attachment were determined, and the FT was measured morphometrically. RESULTS: The FT was present in 50% of fetuses. Four types of FT muscle origin were identified. The most common was Type 2, characterized by an origin on the middle third of the fibula and the intermuscular septum. Three other types were observed: Type 1 with an origin located on proximal third of the fibula and to the intermuscular septum, Type 3 characterized by an absent muscle belly, and an independent tendon originating from the that of the extensor digitorum longus, and Type 4 with an origin located on the distal third of the fibula and the intermuscular septum. CONCLUSIONS: The fibularis tertius demonstrates high morphological variability, with the most common origin located on third of the fibula and to the intermuscular septum.

Case report of unusual insertion of the fibularis brevis muscle.

The fibularis brevis and fibularis longus muscles belong to the lateral compartment of the leg. The fibularis brevis is morphologically variable, especially in the number of tendons and place of insertion. Its type of insertion is correlated with the presence of a fibularis digiti quinti, which is also anatomically variable. We present a case study based on dissection of a seventy-three-year-old female cadaver with an unusual insertion of the fibularis brevis muscle. The tendon had three bands inserting into the fifth metatarsal bone. There was a coexisting fibularis digiti quinti, which was fused with the fibularis tertius muscle. Awareness of such anatomical variation could be useful during reconstructive surgery and planning rehabilitation protocols.

Supernumerary muscles in the posterior leg compartment: a case report / Músculos supernumerarios en el compartimento posterior de la pierna: reporte de un caso

SUMMARY: The leg muscles are organized in anterior, lateral and posterior compartments. The posterior compartment is usually divided in two layers: superficial and deep. The deep muscles of the posterior compartment of the leg are known to mainly plantar flexion and toes flexion. In comparison to the other leg compartments, variations of the posterior one are rare. These variants often involve the presence or absence of one or more muscles, and they have differences among origin and insertion, which leads to confusion between anatomists. We aim to describe a case of a male cadaver that possessed three supernumerary muscles in the lateral and posterior compartments of both legs: the peroneus quartus muscle and two accessory bellies of the flexor digitorum longus. This presentation seems to be very rare and scarcely reported in the literature. These variants have the potential of causing nervous or vascular compression, thus leading to tarsal tunnel syndrome or a symptomatic peroneus quartus. The clinical and surgical implications of this abnormal presentation is discussed.

RESUMEN: Los músculos de la pierna están organizados en compartimentos anterior, lateral y posterior. El compartimento posterior por lo general es dividido en dos capas: superficial y profunda. Se sabe que los músculos profundos del compartimento posterior de la pierna se caracterizan principalmente por participar de la flexión plantar y la flexión de los dedos de los pies. En comparación con los otros compartimentos de la pierna, las variaciones musculares en el compartimiento posterior son raras. Estas variantes suelen implicar la presencia o ausencia de uno o más músculos y presentan diferencias en el origen y en la inserción, lo que conduce a confusión entre los anatomistas. Nuestro objetivo fue describir el caso de un cadáver masculino que poseía tres músculos supernumerarios en los compartimentos lateral y posterior de ambas piernas: el músculo fibular cuarto y dos vientres accesorios del músculo flexor largo de los dedos. Esta presentación parece ser muy rara y escasamente reportada en la literatura. Estas variantes musculares tienen el potencial de causar compresión nerviosa o vascular, lo que conduce al síndrome del túnel del tarso o un cuarto músculo fibular sintomático. Se discuten las implicaciones clínicas y quirúrgicas de esta presentación anormal.

Agreement between upper and lower limb measures to identify older adults with low skeletal muscle strength, muscle mass and muscle quality.

BACKGROUND: Identifying low skeletal muscle strength (SMS), skeletal muscle mass (SMM) and skeletal muscle quality (SMQ) is pivotal for diagnosing sarcopenia cases. Age-related declines in SMS, SMM, and SMQ are dissimilar between the upper (UL) and lower limbs (LL). Despite this, both UL and LL measures have been used to assess SMS, SMM and SMQ in older adults. However, it is not clear whether there is agreement between UL and LL measures to identify older adults with low SMS, SMM and SMQ. OBJECTIVE: To investigate the agreement between UL and LL measures to identify older adults with low SMS, SMM and SMQ. METHODS: Participants (n = 385; 66.1 ± 5.1 years; 75,4% females) performed the handgrip strength test (HGS) and the 30-s chair stand test (CST) to assess UL- and LL-SMS, respectively. The SMM was assessed by dual-energy X-ray absorptiometry (DXA). The UL-SMQ was determined as: handgrip strength (kgf) ÷ arm SMM (kg). LL-SMQ was determined as: 30-s CST performance (repetitions) ÷ leg SMM (kg). Results below the 25th percentile stratified by sex and age group (60-69 and 70-80 years) were used to determine low SMS, SMM and SMQ. Cohen's kappa coefficient (κ) was used for the agreement analyses. RESULTS: There was a slight and non-significant agreement between UL and LL measures to identify older adults with low SMS (κ = 0.046; 95% CI 0.093-0.185; p = 0.352). There was a moderate agreement to identify low SMM (κ = 0.473; 95% CI 0.371-0.574; p = 0.001) and a fair agreement to identify low SMQ (κ = 0.206; 95% CI 0.082 to 0.330; p = 0.005). CONCLUSION: The agreement between UL and LL measures to identify older adults with low SMS, SMM and SMQ is limited, which might generate different clinical interpretations for diagnosing sarcopenia cases.

Musculus peroneus longus in foetal period.

BACKGROUND: The lateral compartment of the leg, due to its distal and concurrent superficial positioning, is a multiple trauma site. Detailed knowledge of compartimentum lateralis cruris (CLC) structure is crucial for physicians. Musculus peroneus longus (MPL) is located within the structures of the CLC most superficially. There is a lot of data on the morphology of the MPL but there is no publication analysing in detail its anatomy in the foetal period. The aim of the study was to determine the variability of metric and morphological parameters of MPL in a studied period of prenatal ontogenesis. MATERIALS AND METHODS: The analysis included 207 human foetuses (101 males and 106 females) at calendar age from 113 to 222 days. The analysed material comes from the local anatomy collection. Foetuses were stored in typical preservation solutions. Access to the muscle was obtained on the basis of standard preparation techniques. The authors evaluated the metric parameters of the muscle showing the presence of variable dynamics of metric increments of the examined muscle in particular age classes. RESULTS: In the studied period of prenatal ontogenesis, MPLs of the foetuses increased by about 60% in the length and width dimension and by about 100% in the thickness dimension. The topography of the initial and final muscle attachment was also evaluated. Statistically significant dimorphic differences were found in some aspects of muscle attachment topography. CONCLUSIONS: The analysis of the place of the origin and insertion of MPL showed a relatively large variety of these features.

Morphological variability of the fibularis tertius tendon in human foetuses.

BACKGROUND: In adults, the fibularis tertius (FT) demonstrates great morphological variation. The present study classifies the types of FT insertion in human foetuses and compares their prevalence to the prevailing classification among adults. MATERIALS AND METHODS: Fifty spontaneously-aborted human foetuses (19 male, 31 female, 100 upper limbs in total) aged 18-38 weeks of gestation at death were examined. The foetuses were obtained from spontaneous abortion after parental consent. The study was performed in accordance with the legal procedures in force in Poland and with the Body Donation Programme for both adults and foetuses. RESULTS: The most common type of FT found was type VI (32%), characterised by a bifurcated distal attachment: a main tendon inserting onto the base of the fourth metatarsal bone, and accessory bands inserting onto the fourth interosseous space. Five other types were observed: type IV (20%), with a single tendon inserting distally to the fascia covering the fourth interosseous space; type I (18%), with a single tendon inserting distally onto the shaft of the fifth metatarsal bone; type V (14%), with a bifurcated arrangement comprising a main tendon characterised by a very wide insertion onto the base of the fifth metatarsal bone and an accessory band inserting onto the base of the fourth metatarsal bone; and type III (12%) with a single tendon inserting distally onto the shaft of the fourth metatarsal bone and fascia covering the fourth interosseous space. Finally, type II (4%) was characterised by a single tendon inserting onto the base of the fifth metatarsal bone via a very wide distal insertion. CONCLUSIONS: The FT demonstrates high morphological variability, with the most common configuration found in adults - a single insertion onto metatarsal 5 - being actually uncommonly found in foetuses.

Associations of Sarcopenia, Handgrip Strength and Calf Circumference with Cognitive Impairment among Chinese Older Adults.

OBJECTIVE: To evaluate the associations of sarcopenia, handgrip strength and calf circumference with cognitive impairment among Chinese older adults. METHODS: Totally 2,525 older adults were recruited from the Healthy Aging and Biomarkers Cohort Study. Cognitive impairment was assessed by the Chinese Mini-Mental State Examination. Handgrip strength was calculated from the means of the right and left hand values. Calf circumference was measured at the site of maximum circumference of the non-dominant leg. The formula developed by Ishii was used to define sarcopenia. Multiple logistic regression was performed to evaluate the associations of sarcopenia, handgrip strength, and calf circumference with cognitive impairment. RESULTS: The prevalence of cognitive impairment was 34.36%. The adjusted odds ratio ( OR) for cognitive impairment in individuals with sarcopenia was 2.55 [95% confidence interval (95% CI): 1.86-3.50]. Compared with individuals in the first quartile (Q 1) of calf circumference, the adjusted ORs in the second, third, and fourth quartiles (Q 2, Q 3, and Q 4) were 0.75 (95% CI: 0.58-0.96), 0.59 (95% CI: 0.44-0.79), and 0.62 (95% CI: 0.45-0.8), respectively. Compared with individuals in Q 1 of handgrip strength, the adjusted ORs for Q 2, Q 3, and Q 4 were 0.49 (95% CI: 0.38-0.62), 0.31 (95% CI: 0.23-0.41), and 0.30 (95% CI: 0.21-0.44), respectively. CONCLUSION: Sarcopenia, identified by low handgrip strength and low calf circumference, was positively associated with cognitive impairment.

Leg length measures appear inaccurate in the early phase following total hip arthroplasty.

The aims of this study were to (1) assess reliability of leg length discrepancy (LLD) measurements at different anatomical landmarks, (2) longitudinally investigate LLD in patients within the first year following total hip arthroplasty (THA) and to (3) correlate changes in LLD with functional outcome. Ninety-nine patients with short stem THA (53.3% males, mean age: 61.0 ± 8.1 years) were prospectively included. Upright pelvic anteroposterior (a.p.) radiographs taken at 6 timepoints (preoperatively, discharge, 6, 12, 24, 52 weeks postoperatively) were used to assess LLD at 5 anatomical landmarks (iliac crest, upper sacroiliac joint, lower sacroiliac joint, tear drop figure, greater trochanter). WOMAC and Harris Hip Score (HHS) were obtained preoperatively and at 6 and 52 weeks. LLD measures significantly increased in the initial phase following THA, from discharge to 6 weeks postoperatively and remained constant thereafter. Documentation of LLDs is dependent on measurement site: LLDs varied significantly between trochanter and iliac crest to tear drop figure (p < 0.001). Functional assessments did not correlate with the occurrence of LLDs [WOMAC (p = 0.252); HHS (p = 0.798)]. Radiographic assessment of LLD following THA may not be performed early postoperatively, as measurements appear to inaccurately reflect actual LLDs at this time, potentially due incomplete leg extension and/or inhibited weight-bearing.

Anatomical consideration of deep calf veins: application to catheter-directed thrombolysis.

PURPOSE: An antegrade approach is frequently used in catheter-directed thrombolysis to remove deep-vein thrombosis. However, the antegrade approach is difficult when accessing veins with small diameters; therefore, understanding the variation of deep calf vein is important. METHODS: This study measured the diameters and surface areas of the proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein to determine which are preferable for venous access. This study dissected 132 legs from Korean and Thai cadavers. The proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein were scanned and measured. RESULTS: The mean diameter and surface area were largest for the proximal tibial vein, at 6.34 mm and 0.312 cm2, respectively, followed by the anterior tibial vein (5.22 mm and 0.213 cm2), distal posterior tibial vein (3.29 mm and 0.091 cm2), and peroneal vein (3.43 mm and 0.081 cm2). The proximal posterior tibial vein and anterior tibial vein have large diameters and surface areas, which make them ideal for applying an antegrade approach in catheter-directed thrombolysis. CONCLUSIONS: The distal posterior tibial vein and peroneal vein are not recommended due to their smaller surface areas and also the anatomical variations therein.

An accessory muscle of the posterior compartment of leg of clinical significance: a cadaveric case report / Un músculo accesorio del compartimento posterior de la pierna de importancia clínica: reporte de un caso cadavérico

SUMMARY: Accessory and anomalous muscles are common in humans, although their unique morphologic characteristics can make accurate identification difficult. In this case report, we attempt to identify an anomalous accessory muscle of the posterior compartment of the leg [Compartimentum posterius cruris] detected during cadaveric dissection and discuss its clinical significance. The muscle was found on the right lower limb of an 81-year-old female cadaver and extended from the distal femur to attach to the gastrocnemius muscle at the point where the medial and lateral heads fuse. At its origin, the muscle was found lateral to the popliteal vessels and crossed posterior to these vessels and tibial nerve. It displayed characteristics similar to both an accessory plantaris muscle and gastrocnemius tertius, thus making its ultimate identification difficult. Though the muscle displayed a morphologically similar appearance to the plantaris, we suggest that its common insertion with the gastrocnemius best identifies it as a gastrocnemius tertius. In addition, due to its relationship with the popliteal neurovasculature, it is possible that this muscle could have resulted in neurovascular entrapment although it is unknown whether or not this cadaver exhibited symptoms.

RESUMEN: Los músculos accesorios y anómalos son comunes en los seres humanos, aunque sus características morfológicas pueden dificultar la identificación precisa. En este reporte de caso, intentamos identificar un músculo accesorio anómalo del compartimento posterior de la pierna [Compartimentum posterius cruris] detectado durante la disección cadavérica y discutir su importancia clínica. El músculo fue encontrado en el miembro inferior derecho de una mujer de 81 años de edad y se extendía desde la parte distal del fémur para unirse al músculo gastrocnemio en la fusión de sus cabezas medial y lateral. En su origen, el músculo se encontraba lateral a los vasos poplíteos y cruzaba posteriormente a estos vasos y al nervio tibial, presentando características similares tanto al músculo plantar accesorio como al gastrocnemio tercero, lo que dificultaba su identificación final. Similar al músculo plantar, sugerimos que debido a su inserción común con el gastrocnemio lo identifica mejor como un músculo gastrocnemio tercero. Además, debido a su relación con la neurovasculatura poplítea, es posible que este músculo haya dado lugar a un síndrome de compresión neurovascular aunque se desconoce si este individuó presentó síntomas o no en vivo.

Muscle Activity and Morphology in Slalom Skiing by a Single-Leg Amputee Ski Racer: A Case Study of a Paralympic Athlete.

The aim of this study was to clarify the characteristics of skiing by a single-leg amputee ski racer from the viewpoints of muscle activity, morphology, and the relationship between both elements through comparisons with those of a non-disabled ski racer. One elite athlete, classified as LW2 (left thigh amputation), and one non-disabled athlete, as a control, participated in this study. The cross-sectional area of thigh muscles was measured through magnetic resonance imaging. Additionally, muscle activities and joint and segment kinematics during slalom skiing were measured using electromyography and inertial measurement units, respectively. The muscle activities and joint kinematics of the amputee racer in the turn in which he performed with the inside edge of the ski were similar to those of the outside leg of the non-disabled racer over a turn. In contrast, at the turn in which the amputee racer performed with the outside edge (more difficult side), the amputee racer largely activated the biceps femoris (BF) in the first half of the turn compared to the non-disabled racer. The reason could be to control the angular momentum of the trunk during the forward tilting motion. This is because a greater activity of the BF was observed during the period in which the forward tilt of the trunk was increased, and the mean activity of the BF was the greatest during the first half of the right turn in which the range of the motion of the forward tilt was the greatest. In terms of muscle morphology of the amputee racer, a significant hypertrophy of the BF and vastus lateralis was observed compared to the non-disabled racers. The well-developed BF was considered to be related to the large activity during the turn performed with the outside edge of the ski.