Anatomic motor point localization for the treatment of gastrocnemius muscle spasticity

The location of the motor point of the gastrocnemius muscle was accurately defined relative to surrounding bony landmarks to facilitate the approach to the nerve of the gastrocnemius muscle during treatment for gastrocnemius muscle spasticity. Anatomic dissection of 40 cadaver knees was undertaken for morphometric measurement. The distances from the epicondyle of the femur to the motor branch, and from the motor branch to the motor point of the nerve to the medial head of the gastrocnemius muscle were 3.68 +/- 11.44 mm, and 37.79 +/- 7.80 mm, respectively; while those of the nerve to lateral head of the gastrocnemius muscle were 4.45 +/- 11.96 mm, and 32.16 +/- 4.64 mm, respectively. The tibial nerve lay 44.57 +/- 5.45% and 56.30 +/- 4.73% from the lateral margins of the epicondyle and the fibular head, respectively. Careful consideration of the morphometry of the motor point of the gastrocnemius muscle may provide accurate anatomical guidance, and hence reduce complications during the chemical blockage of these nerves.     

Anatomic variations of the musculotendinous junction of the soleus muscle and its clinical implications

The soleus muscle, like the gastrocnemius, is a powerful plantarflexor muscle in the lower limb. The soleus muscle joins the aponeurosis of the gastrocnemius muscle to form the calcaneal (Achilles) tendon. While the basic anatomy of the soleus muscle has been previously described, no study has addressed the anatomical variations of its distal attachment. We found considerable anatomic variation in the distance between this musculotendinous junction and the most proximal point of the proximal edge. This distal measuring point was defined as the most proximal point of the proximal edge of the posterior surface of the calcaneal tuberosity. Eighty human cadaver specimens were preserved according to Thiel's method; we examined one limb from each cadaver, studying 80 lower extremities in total. Following careful dissection of the lower limb, we measured the distance between the distal point of attachment of the soleus muscle fibers (the musculotendinous junction) and the designated measuring point. Our findings were divided into three groups: Group 1 (10 cases, 12.5%), where the distance between the musculotendinous junction and the designated point on the calcaneal tuberosity was between 0 and 1 inches; Group 2 (56 cases, 70%), where the distance was between 1 and 3 inches; and Group 3 (14 cases, 17.5%), where the distance was greater than 3 inches. Detailed knowledge of the anatomic variations of the soleus muscle at its insertion point onto the calcaneal tendon has clinical implications in calcaneal tendon repair following rupture and in the planning of reconstructive surgery using soleus muscle flaps.     

膝后外侧部结构的断层解剖及临床意义

目的：为MRI诊断膝后外侧部结构损伤提供断层解剖学依据。方法：用火棉胶包埋技术对8侧成人尸体膝部进行矢状和冠状位l～2mm厚的连续切片，观察膝后外侧部结构在断面上的形态、位置和毗邻关系。结果：腓侧副韧带和弓状韧带在冠状切片显示较好；小豆腓骨韧带在矢状切片显示较好；胭腓韧带在矢状和冠状切片均可显示；胭肌的肌腹部、肌腹一肌腱连接部和胭肌腱股骨部在冠状层面可显示，胭肌腱斜行部在矢状面显示较好。结论：膝部矢状和冠状断层切片能清晰显示膝后外侧部结构，有利于正确辨认这些结构的影像学表现。     

The plantaris tendon and a potential role in mid-portion Achilles tendinopathy: an observational anatomical study

The source of pain and the background to the pain mechanisms associated with mid-portion Achilles tendinopathy have not yet been clarified. Intratendinous degenerative changes are most often addressed when present. However, it is questionable if degeneration of the tendon itself is the main cause of pain. Pain is often most prominent on the medial side, 2-7cm from the insertion onto the calcaneus. The medial location of the pain has been explained to be caused by enhanced stress on the calcaneal tendon due to hyperpronation. However, on this medial side the plantaris tendon is also located. It has been postulated that the plantaris tendon might play a role in these medially located symptoms. To our knowledge, the exact anatomy and relationship between the plantaris- and calcaneal tendon at the level of complaints have not been anatomically assessed. This was the purpose of our study. One-hundred and seven lower extremities were dissected. After opening the superficial fascia and paratendon, the plantaris tendon was bluntly released from the calcaneal tendon moving distally. The incidence of the plantaris tendon, its course, site of insertion and possible connections were documented. When with manual force the plantaris tendon could not be released, it was defined as a 'connection' with the calcaneal tendon. In all specimens a plantaris tendon was identified. Nine different sites of insertion were found, mostly medial and fan-shaped onto the calcaneus. In 11 specimens (10%) firm connections were found at the level of the calcaneal tendon mid-portion. Clinical and histological studies are needed to confirm the role of the plantaris tendon in mid-portion Achilles tendinopathy.     

Musculo-tendinous junction of the flexor carpi ulnaris muscle. An anatomical study

The aim of the study was to evaluate the occurrence of the anatomical variations of the musculotendinous junction of the flexor carpi ulnaris (FCU) muscle and the variations of its insertion onto the pisiform. One hundred cadaver specimens preserved according to Thiel’s method were assessed. Following careful dissection, the distance between the musculotendinous junction and the pisiform and the width of the muscle belly were determined. Three typical anatomical variations were found 1) a large muscle belly running distally almost to the insertion onto the pisiform 2) the muscle belly ending more proximally, with some large fibres running parallel to the tendon and almost reaching the pisiform 3) the musculotendinous junction ending more proximally, with only single fibres continuing distally. The length of the tendon was greater than 10 mm. A number of variations of the distal region of FCU were observed. The presence of muscle fibres almost reaching the insertion point onto the pisiform have to be considered when interpreting MRI or ultrasound findings of this region.     

Influence of a fabella in the gastrocnemius muscle on the common fibular nerve in Japanese subjects

The fabella is a sesamoid bone located in the proximal tendon of the gastrocnemius muscle. In rare cases, its presence may lead to a variety of clinical problems, including fabella syndrome and common fibular (CF) nerve palsy. The purpose of this study was to analyze the morphology of the fabella and CF nerve and discuss the influence of any existing fabellae on the size of the CF nerve. The morphology of the fabella and CF nerve in the popliteal region of the lateral head of the gastrocnemius muscle was investigated in 102 knees of 51 Japanese cadavers. The maximum circumference of the thigh, knee, and calf and the frequency, position, and size of the fabella were measured. In addition, the CF nerve width and thickness were measured proximal to the fabellar region and again as the CF nerve passed posterior, lateral, or medial to the region. A fabella was observed in 70 knees (68.6%). The CF nerve adjacent to the fabella was significantly wider and thinner than in the region proximal to the fabella (P < 0.001). In cases in which a bony fabella was present, there was a significant relationship between the thickness of the CF nerve and the circumference of the thigh and knee. The following factors were observed to contribute to the presence of a fabella causing alterations in the size of the CF nerve: a bony fabella, a CF nerve path posterior or lateral to the fabella, and subjects with a thin physique and bony fabella. Clin. Anat. 26:893–902, 2013. © 2012 Wiley Periodicals, Inc.     

Structure of the human tibialis anterior tendon

The structure and vascular pattern of the human tibialis anterior tendon was investigated using injection techniques, light and transmission electron microscopy and immunohistochemistry. From the well vascularised peritenon, blood vessels penetrate the tendon tissue and anastomose with a longitudinally oriented intratendinous network. The distribution of blood vessels within the tibialis anterior tendon was not homogenous. The posterior part of the tendon had a complete vascular network that extends from the musculotendinous junction to the insertion at the first metatarsal and medial cuneiform bones. In the anterior half, the tissue was avascular in a zone with a length of 45–67 mm. This zone was covered by a single layer (∼30 μm) of oval shaped cells. Transmission electron microscopy showed that these cells have the characteristics of chondroid cells. This region was stained by Alcian blue at pH 1 which indicates a high concentration of acid glycosaminoglycans and immunohistochemical staining for chondroitin-4-sulphate, chondroitin-6-sulphate and aggrecan was positive. However, immunostaining for the typical cartilage specific type II collagen within this zone was negative. The location of the avascular zone corresponds to the region where the tibialis anterior tendon wraps around the superior and inferior retinacula which serve as fibrous pulleys. This is the region where most spontaneous ruptures of the tibialis anterior tendon occur. The presence of fibrocartilage within gliding tendons is a functional adaptation to compressive and shearing forces. In contrast to reports from the literature about the structure of gliding tendons wrapping around a bony pulley, the gliding zone of the tibialis anterior tendon has only a narrow layer of chondroid cells and proof of type II collagen is lacking.     

Musculo-tendinous junction of the flexor carpi ulnaris muscle. An anatomical study

The aim of the study was to evaluate the occurrence of the anatomical variations of the musculotendinous junction of the flexor carpi ulnaris (FCU) muscle and the variations of its insertion onto the pisiform. One hundred cadaver specimens preserved according to Thiel's method were assessed. Following careful dissection, the distance between the musculotendinous junction and the pisiform and the width of the muscle belly were determined. Three typical anatomical variations were found: 1) a large muscle belly running distally almost to the insertion onto the pisiform; 2) the muscle belly ending more proximally, with some large fibres running parallel to the tendon and almost reaching the pisiform; 3) the musculotendinous junction ending more proximally, with only single fibres continuing distally. The length of the tendon was greater than 10 mm. A number of variations of the distal region of FCU were observed. The presence of muscle fibres almost reaching the insertion point onto the pisiform have to be considered when interpreting MRI or ultrasound findings of this region.     

锤状指治疗中固定指位的应用解剖研究

目的 探讨成人新鲜上肢标本指间关节活动对伸肌腱Ⅰ~Ⅱ区伸肌腱的影响,为临床锤状指治疗中固定指位的选择提供解剖学基础。方法 纳入成人新鲜上肢标本16侧,取示、中、环、小指各16指,分别于各指在近侧指间关节0°伸直位、45°屈曲位和90°屈曲位时,测量远侧指间关节的最大被动屈曲角度。显露伸肌腱Ⅰ~Ⅱ区,制作锤状指畸形模型,克氏针在中节指骨颈水平垂直于指骨长轴穿透指骨作为参照,于伸肌腱Ⅱ区上做标记,测量肌腱滑动距离。固定远侧指间关节于0°伸直位,近侧指间关节自0°伸直位至90°屈曲位,观察伸肌腱Ⅱ区断端间隙距离的变化,并测量肌腱的滑动距离。结果 实验显示,当近侧指间关节于90°屈曲位时,远侧指间关节的最大被动屈曲角度较近侧指间关节于0°伸直位时增加约21%;近侧指间关节处于0°伸直位时,示指、中指、环指及小指的伸肌腱Ⅱ区末端断端间隙距离分别为(0.35±0.06)mm、(0.42±0.05)mm、(0.46±0.06)mm、(0.51±0.08)mm;固定远侧指间关节,屈曲近侧指间关节至90°屈曲位时,近侧断端向远侧滑移,示指、中指、环指及小指的滑移距离分别为(0.69±0.09)mm、(0.74±0.03)mm、(0.80±0.07)mm、(0.81±0.10)mm,且最终远近两侧断端重叠。结论当远侧指间关节于轻度过伸位、近侧指间关节于屈曲位时,断端间隙消失,此时伸肌腱Ⅰ~Ⅱ域区松弛,张力降低。在锤状指治疗应用上述指位可降低肌腱张力,利于肌腱愈合。     

Structure of the Achilles tendon at the insertion on the calcaneal tuberosity

Findings on the twisting structure and insertional location of the AT on the calcaneal tuberosity are inconsistent. Therefore, to obtain a better understanding of the mechanisms underlying insertional Achilles tendinopathy, clarification of the anatomy of the twisting structure and location of the AT insertion onto the calcaneal tuberosity is important. The purpose of this study was to reveal the twisted structure of the AT and the location of its insertion onto the calcaneal tuberosity using Japanese cadavers. The study was conducted using 132 legs from 74 cadavers (mean age at death, 78.3 ± 11.1 years; 87 sides from men, 45 from women). Only soleus (Sol) attached to the deep layer of the calcaneal tuberosity was classified as least twist (Type I), both the lateral head of the gastrocnemius (LG) and Sol attached to the deep layer of the calcaneal tuberosity were classified as moderate twist (Type II), and only LG attached to the deep layer of the calcaneal tuberosity was classified as extreme twist (Type III). The Achilles tendon insertion onto the calcaneal tuberosity was classified as a superior, middle or inferior facet. Twist structure was Type I (least) in 31 legs (24%), Type II (moderate) in 87 legs (67%), and Type III (extreme) in 12 legs (9%). A comparison between males and females revealed that among men, 20 legs (24%) were Type I, 57 legs (67%) Type II, and eight legs (9%) Type III. Among women, 11 legs (24%) were Type I, 30 legs (67%) Type II, and four legs (9%) Type III. No significant differences were apparent between sexes. The fascicles of the Achilles tendon attach mainly in the middle facet. Anterior fibers of the Achilles tendon, where insertional Achilles tendinopathy is most likely, are Sol in Type I, LG and Sol in Type II, and LG only in Type III. This suggests the possibility that a different strain is produced in the anterior fibers of the Achilles tendon (calcaneal side) where insertional Achilles tendinopathy is most likely to occur in each type. We look forward to elucidating the mechanisms generating insertional Achilles tendinopathy in future biomedical studies based on the present results.     

带腓肠肌肌腱的腓肠神经营养血管复合皮瓣修复跟腱并皮肤缺损

目的探讨带腓肠肌肌腱的腓肠神经营养血管复合皮瓣修复跟腱并皮肤缺损的效果。方法复合皮瓣修复跟腱并皮肤缺损6例,其中3例跟腱背侧部分缺损,2例跟腱内侧部分缺损,1例跟腱完全缺损。切取带腓肠肌肌腱的腓肠神经营养血管复合皮瓣时,保持肌腱与皮瓣深筋膜的联系。皮瓣大小7cm×5cm～11cm×10cm,腓肠肌肌腱大小为5cm×3cm～9cm×4cm。结果6例皮瓣均完全成活,感染控制;6例术后随访3～50个月,皮瓣外观满意,无跟腱再断裂者。患侧踝关节屈伸范围基本正常,功能评定,优5例,良1例。结论带腓肠肌肌腱的腓肠神经营养血管复合皮瓣修复跟腱并皮肤缺损具有手术操作简单,术后跟腱粘连轻,功能恢复好的优点。     

Gliding characteristics of flexor tendon and tenosynovium in carpal tunnel syndrome: a pilot study

The characteristic pathological finding in carpal tunnel syndrome (CTS) is noninflammatory fibrosis of the synovium. How this fibrosis might affect tendon function, if at all, is unknown. The subsynovial connective tissue (SSCT) lies between the flexor tendons and the visceral synovium (VS) of the ulnar tenosynovial bursa. Fibrosis of the SSCT may well affect its gliding characteristics. To investigate this possibility, the relative motion of the flexor tendon and VS was observed during finger flexion in patients undergoing carpal tunnel surgery, and for comparison in hands without CTS, in an in vitro cadaver model. We used a camera to document the gliding motion of the middle finger flexor digitorum superficialis (FDS III) tendon and SSCT in three patients with CTS during carpal tunnel release and compared this with simulated active flexion in three cadavers with no antemortem history of CTS. The data were digitized with the use of Analyze Software (Biomedical Imaging Resource, Mayo Clinic, Rochester, MN). In the CTS patients, the SSCT moved en bloc with the tendon, whereas, in the controls the SSCT moved smoothly and separately from the tendon. The ratio of VS to tendon motion was higher for the patients than in the cadaver controls. These findings suggest that in patients with CTS the synovial fibrosis has altered the gliding characteristics of the SSCT. The alterations in the gliding characteristics of the SSCT may affect the ability of the tendons in the carpal tunnel to glide independently from each other, or from the nearby median nerve. These abnormal tendon mechanics may play a role in the etiology of CTS.     

Musculotendon excursion potential,tendon slack and muscle fibre length: the interaction of the canine gastrocnemius muscle and tendon

Although the form‐function relation of muscles and tendons has been studied extensively, little in vivo data exist on the musculotendon properties of the gastrocnemius complex in dogs. Using a combination of ultrasound and 3D motion tracking, musculotendon parameters were obtained in vivo from the lateral gastrocnemius muscle and the gastrocnemius tendon in nine healthy Labrador Retrievers. These parameters include musculotendon length and excursion potential, tendon slack length, muscle belly length, muscle fibre length, pennation angle and architectural index. This study also examined the variation of muscle and tendon length contributions to musculotendon length, as well as the relation between musculotendon excursion potential and muscle fibre length or tendon length. To facilitate comparison between dog breeds, the femur length as a potential scaling parameter was examined. In the Labrador gastrocnemius musculotendon complex, the tendon contributes 41% (± 9%) of musculotendon length. In longer musculotendon complexes, the contribution of the muscle belly increases while the tendon contribution decreases. Longer muscle belly and musculotendon complexes were, however, associated with shorter muscle fibres. No significant relations were found between musculotendon excursion potential and muscle fibre length or tendon slack length, and femur length did not prove to be a reliable scale factor for the length‐related musculotendon parameters examined in this study. Longer musculotendon complexes exhibit relatively longer muscle bellies, which are in turn associated with shorter muscle fibre lengths. This trade‐off between gastrocnemius muscle belly length and muscle fibre length might have the advantage that muscle volume stays constant regardless of the length of the limbs.     

Effect of ageing on ultrastructure of slow and fast skeletal muscle tendon in rabbit Achilles tendons

This reports presents the changing morphological characteristics of collagen and fibroblasts in the soleus and gastrocnemius muscle tendon of female Japanese white rabbits with ageing. The fibroblasts decreased in number per 37 μm² with ageing in each group, and their morphology became longer and more slender through ageing. The mean fibril area and diameter of the collagen fibrils of soleus muscle tendon (SMT) and lateral gastrocnemius muscle tendon (GMT) in 8- to 10-month old rabbits were significantly higher than those of 3-wk-old rabbits during growth (P < 0.01). The mean area and diameter of collagen fibrils of SMT and GMT decreased during senescence: the values for 4- to 5-yr-old rabbits were lower than those for 8- to 10-month-old rabbits, but the difference was not significant. Statistically significant differences in fibril area and diameter between the SMT and GMT were not found during ageing. The number of thick fibrils increased during growth, but decreased in senescence. There were more thin fibrils (30–60 nm) in the 3-wk-old rabbits than in the 8- to 10-month old and 4 to 5-yr-old groups, and the large-diameter collagen (300–360 nm) was more abundant in the 8- to 10-month-old group than in the 3-wk-old and 4- to 5-yr-old groups. Differences in fibril size between slow and fast muscle tendons were not observed during ageing.     

小腿有关肌腱转位修复跟腱的生物力学评价

目的：为临床选用自体肌腱转位修复跟腱提供生物力学依据。方法：选用防腐固定成年和新鲜青年下肢各７例。制备拉伸试件，在ＳＷＤ－１０型材料试验机上，进行单向拉伸破坏实验。结果：跟腱、腓骨长肌腱、腓骨短肌腱、胫骨后肌腱及展肌腱固定组分别为２２９２．６Ｎ、１０２０．５Ｎ、７５２．０Ｎ、９３８．９Ｎ和７２１．３Ｎ，新鲜组分别为１９２７．１Ｎ、８１９．５Ｎ、３４６．７Ｎ、６９９．７Ｎ、３０３．８Ｎ。结论：腓骨长肌腱是跟腱缺损修复术较理想的自体材料。     

Revision of hip flexor anatomy and function in modern humans,and implications for the evolution of hominin bipedalism

Hip flexor musculature was instrumental in the evolution of hominin bipedal gait and in endurance running for hunting in the genus Homo. The iliacus and psoas major muscles were historically considered to have separate tendons with different insertions on the lesser trochanter. However, in the early 20th century, it became “common knowledge” that the two muscles insert together on the lesser trochanter as the “iliopsoas” tendon. We revisited the findings of early anatomists and tested the more recent paradigm of a common “iliopsoas” tendon based on dissections of hips and their associated musculature (n = 17). We rediscovered that the tendon of the psoas muscle inserts only into a crest running from the superior to anterior aspect of the lesser trochanter, separate from the iliacus. The iliacus inserts fleshly into the anterior portion of the lesser trochanter and into an inferior crest extending from it. We developed 3D multibody dynamics biomechanical models for: (a) the conjoint “iliopsoas” tendon hypothesis and (b) the separate insertion hypothesis. We show that the conjoint model underestimates the iliacus' capacity to generate hip flexion relative to the separate insertion model. Further work reevaluating the primate lower limb (including human) through dissection, needs to be performed to develop those datasets for reconstructing anatomy in fossil hominins using the extant phylogenetic bracket approach, which is frequently used for tetrapods clades outside of paleoanthropology.     

A previously unreported variation related to the insertion of the tibialis anterior muscle and the superficial fibular (peroneal) nerve

During dissection classes in 2003 in the Department of Anatomy at Ege University Faculty of Medicine, an unexpected variation of the insertion of the tibialis anterior tendon was determined on the right side of a formalin-fixed cadaver of a 40-year-old man without any trace of scars, adhesions or signs of trauma or operation. The insertion of the tibialis anterior tendon was very abnormal, not on the medial side of the foot but on the lateral side. The tibialis anterior is an important muscle because of its function and use in tendon transfer as a treatment of recurrent congenital clubfoot and paralytic equinovarus foot deformities in cerebral palsy and arthroscopy, as discussed herein.     

Anatomical and computed tomography study of the eighth costochondral junction: topography for costochondral graft harvesting

Introduction

Costochondral grafts have long been used in maxillofacial reconstruction, but have been little used in trauma and orthopedic cases. This surgical technique requires that a graft be harvested from the thorax in the area of the eighth rib. Pleuropulmonary complications are very rare. Although the harvesting technique is simple, it needs to be demystified.

Goal of study

This study was performed to define anatomical relationships in the eighth costochondral junction and identify topographical and anatomical landmarks that will make it easier to harvest this structure.

Method

This was a two-part study. First, an anatomical study was carried out on human cadaver thoraxes to define topographical landmarks and study the anatomical surroundings of the eighth costochondral junction. Second, an imaging study was performed using a database of existing patient computed tomography (CT) scans of the chest and abdomen to confirm the topographical landmarks defined in the first part of the study. The spine was used as a reference for both studies. The location of the eighth costochondral junction was defined relative to the spinal processes along with its location on the lower rib cage hemiperimeter in the transverse plane starting at the corresponding spinous process.

Results

The eighth costochondral junction was in line with the spinal process of the twelfth thoracic vertebra in the vast majority of cases and located at two-thirds of the lower rib cage hemiperimeter from the posterior median sulcus, regardless of the patient’s chest shape, age and gender. This junction was always located under a single muscle (external oblique) and protected by a thick perichondrium layer, which separates it from the intercostal pedicles, endothoracic fascia and parietal pleura.

Discussion

This two-part study has identified reliable landmarks for harvesting of an osteochondral graft at the eighth costochondral junction and, by describing its anatomical surroundings, helps take the mystery out of its harvesting. These landmarks were identified in supine cadavers and in free-breathing patients lying in supine for the CT portion. This position must be used when identifying these landmarks in a patient undergoing costochondral autograft harvesting for cartilage reconstruction.

     

bFGF复合膜对同种异体肌腱移植的作用的实验研究

目的　用bFGF复合膜 ,包裹在腱移植处 ,探讨腱内部再生是否快于腱周结缔组织增生 ,从而达到防止或减轻腱粘连的目的。方法　用 - 80℃冰箱冷存 10天的同种异体跟腱缝接 30只兔左肢跟腱缺损 2 .0cm处 ,分两组 :A组在腱移植处包裹bFGF复合非降解膜 (药膜 )为实验组 ,B组在腱移植处包裹无药的非解降解膜 (无药膜 )为对照组 ,术后不同时间 ,切取腱移植部位 ,常规制成光、电镜标本 ,再行镜下观察 ,图像分析仪测定和腱周粘连定量测定。结果　包药膜腱移植段内部的成纤维细胞和胶原纤维明显较无药膜的多 (<0 0 1) ,包无药膜腱周结缔组织的成纤维细胞和胶原纤维明显较包膜的多 (<0 0 1) ,包药膜腱移植段内部的成纤维细胞和胶原纤维明显较腱周结缔组织的多 (<0 1) ,无药膜的明显较腱周的少 (<0 0 1)。结论　bFGF复合膜有增强腱内部再生和减轻或防止腱粘连的作用     

腹外斜肌移位代股四头肌的应用解剖学

在50侧成人尸体上测量观察了邻外斜肌的面积、厚度、纤维长度 肌门数目、位置及穿过肌门的血管神经束长和动脉管径。讨论了小儿麻痹后遗症以腹外斜肌腱移位代替股四头肌手术中关于肌力、肌力与肌纤维方向的关系,并指出分离腹外斜肌时如何注意出血。