胸大肌合并背阔肌额外肌束变异1例

<正>笔者在一具男尸(约65岁)的解剖中,发现左侧胸大肌和背阔肌同时有变异肌束出现,为积累国人解剖形态学资料,现从胸大肌与背阔肌额外肌束的起止、走行、形态、血供以及神经支配等方面予以报道。1.胸前壁变异肌束位于左侧胸大肌下缘,呈扁条状,斜向外上走行,大体分三段(图1):起始部以三角形腱膜附于剑突下腹直肌前鞘,腱膜起始部宽4.85 cm,长6.9 cm,移行至肌腹部宽1.2 cm;中段为肌腹部分,行于胸大肌下缘,与胸大肌下     

肌皮神经变异1例

作者在解剖1具10%福尔马林固定的被解离的成年男性左上肢时,发现其肌皮神经变异,查阅相关文献,本例变异未经报道,为积累解剖学资料,报道如下:本例左侧臂丛外侧束发出1细支,穿进喙肱肌并支配该肌,该分支横径约1.2 mm;正中神经合成正常,在下行过程中发出肌皮神经。以喙突平面为测量点,左侧肌皮神经发出点距胸小肌下缘4.4 cm,横径3.2 mm。左侧肌皮神经下行4.3 cm发出分支支配肱二头肌,继续下行4.6 cm发出另一分支支配肱肌,主干走行在肱二头肌与肱肌之间并从肱二头肌外侧缘穿出延续为前臂外侧皮神经(图1)。     

胸锁乳突肌、背阔肌起止点变异1例

胸锁乳突肌、背阔肌起止点变异１例杨连柱①姜常勇①李佳林①在解剖１具成年女尸时，发现其右侧胸锁乳突肌分三束起始，即胸骨头、内侧锁骨头、外侧锁骨头。右侧背阔肌除固有止端腱至肱骨小结节嵴外，尚有一分离肌束延为腱膜并与胸大肌止端腱融合。此类变异甚少见，报道如...     

双侧背阔肌止点变异合并右侧高位尺动脉一例

我们在教学解剖过程中,发现双侧背阔肌多处止点合并右侧高位尺动脉一例,此种变异情况罕见,特报道如下。男尸,40岁左右,身高约175cm,体态匀称。双侧背阔肌均在肌前缘又发出一个变异肌束,肌腱走行于腋窝淋巴结群及腋窝血管神经的前方,与腋窝血管神经鞘的筋膜相连。左侧肌束宽10mm     

左侧肌皮神经缺如变异一例

<正>笔者在局部解剖学实验课解剖一成年男尸过程中,发现其左侧肌皮神经缺如变异,原肌皮神经支配和分布范围由正中神经各分支所代替,且正中神经在臂部行程也有变异,右侧肌皮神经正常。为积累资料及提供临床医生参考,现报道如下。该例左侧臂丛内侧束发出正中神经内侧根(横径为3.04mm),外侧束发出2个根,即正中神经外侧根(横径为5.66 mm)和正中神经外侧附根(横径为1.6 mm)。附根越腋动脉第2段前方先与内侧根吻合。正中神经内、外侧根分别沿腋动脉内、外侧下行至胸大肌下缘,距喙突75.00 mm处,外侧根越腋动脉前方与     

双侧胸小肌止点变异1例

在解剖一具６０岁左右男性尸体过程中,发现其双侧胸小肌止点变异,报道如下：其双侧胸小肌起点正常,起于第３、４、５肋骨前面;止点以肩胛骨喙突为滑车,以肌腱绕过喙突在冈上肌肌腱上方止于内侧肩关节囊的内层。腱长度为３ｃｍ。在胸小肌肌腱绕行喙突的行程中,有一束增厚的扇形纤维将该肌腱与喙锁韧带相连。胸小肌血液供应是来自胸肩峰动脉和胸外侧动脉,神经支配为胸前神经。作者单位：１１６０２７　大连医科大学生物塑化研究所附图　双侧胸小肌止点变异双侧胸小肌止点变异1例@孟文件!116027$大连医科大学生物塑化研究所@常宝林!1160…     

左侧肌皮神经缺如1例

笔者在解剖1成年女尸,发现其左侧肌皮神经缺如变异,原肌皮神经支配和分布范围由正中神经各分支所代替,右侧肌皮神经正常.为积累资料及提供临床医生参考,现报道如下: 该例左侧臂丛的内侧束、外侧束及后束分别位于腋动脉的后方、前外侧及内侧.内侧束和外侧束分别发出正中神经内侧根和外侧根,两根在胸小肌下缘,腋动脉前方合并成正中神经干,下行距两根汇合点2.3 cm处又分成正中神经内侧支和外侧支,2支并行下行10.4 cm再次汇合为正中神经干.在臂上部,正中神经行于肱动脉前外侧;约在臂中部,斜过肱动脉后方至其内侧下行至肘窝.     

背阔肌复合组织瓣转位重建上肢运动功能的解剖学研究

目的　为背阔肌复合组织瓣转位重建上肢运动功能提供解剖学依据。  方法　通过解剖16侧10%福尔马林液固定成人尸体标本,观察背阔肌形态变化及其起点处与腰背肌的解剖结构关系。使用SPSS 13.0统计软件进行数据统计。  结果　背阔肌起点处肌质薄,肌束分两大部分,肌束方向不一致,胸背神经分两支分别支配。背阔肌起点处与腰背肌表面的胸腰筋膜愈着紧密,此处胸腰筋膜腱膜增厚;背阔肌起点处与腰背肌之间有血管、神经自肌肉深面穿过,解剖位置恒定。  结论　背阔肌解剖形态特点及胸背神经支配特点是肌肉转位后前臂力量不足的主要原因;背阔肌携带起点处的浅层腰背肌肉的背阔肌复合组织瓣可以增强转位术后前臂肌力,且无需吻合血管。     

胸大肌腹部及背阔肌异常一例

作者在解剖一具青年男性尸体时发现其右侧胸大肌腹部和背阔肌变异。该例右侧胸大肌腹部可被明显的分为两部分肌束,上方部分起于腹直肌鞘前层的上份,肌束斜向后外上方与胸大肌的胸部和锁骨部共同止于肱骨大结节嵴,其肌腹长16.8cm,最宽处宽1.4cm,最宽处厚0.4cm;下方部分也起于腹直肌鞘前层的上份,肌束斜向后外上方,在腋中线附近以腱性结构止于背阔肌,此肌束长13.1cm,止点处宽0.8cm,止点处厚0.7cm。     

腋弓肌与锁枕肌一例

成年男尸身高1.7米,年龄约45岁,外观发育正常,但发现四块肌肉异常——双侧腋弓肌与锁枕肌:1.左侧胸大肌与左侧背阔肌:左胸大肌下缘发现一肌束长20 cm、宽1～1.5 cm、厚0.7 cm,起于腹直肌鞘外上方,肌束外上2/3游离并与背阔肌前上缘分出的长3cm、宽3cm、厚0.6cm一肌束融合后,移行为一长7 cm,宽1.5～5.5 cm的鸭蹼状腱,腱     

Axillopectoral muscle (Langer's muscle)

In a routine dissection of the axillary fossa, a muscle originating from the coracoid process of the scapula and extending to the long head of triceps brachii muscle was observed. The mentioned muscle was adhering to both the triceps brachii muscle and the tendinous part of the latissimus dorsi muscle. This anatomical variation is referred to as axillary arch (Langer's muscle or axillopectoral muscle). The muscle mass was measured 9.6 cm in length and 1.4 cm in width. The accessory muscle can be a reason of an axillary mass and can exert pressure on the neighboring neurovascular bundle or lymph routes; thus, exposing a wide range of symptoms. Therefore, variations of this area should be kept in mind in surgical interventions.     

Distribution of slow muscle fiber of muscle spindle in postnatal rat masseter muscle

We investigated the properties of the muscle spindle in the masseter muscle at an immunohistochemical level in rats fed for 6 weeks. Slow myosin heavy chain (MyHC) isoforms were measured and intrafusal fibers in the muscle spindle were studied to determine the relationship between the superficial and deep regions of rat masseter muscle after alternated feeding pattern. However, muscle spindles were found in both regions, mainly in the deep region of the posterior superficial region of masseter muscle. The total number of the slow fiber in the intrafusal fiber and number of muscle spindle in the deep region were high from 5 to 8 weeks old in spite of various dimensions of data such as diameter and the compositions of the intrafusal fiber. The relationship of the protein expression of slow MyHC in the two regions at 5 weeks old reversed five weeks later (10 weeks old). This period is an important stage because the mastication system in masseter muscle with muscle spindle may be changed during the alternated feeding pattern of suckling to mastication. The changes may be a marker of the feeding system and of the control by the tension receptor of muscle spindle in this stage of masseter muscle after postnatal development.     

Peroneotalocalcaneous muscle

Variations within the musculature of the lateral compartment of the leg are uncommon. However, clinicians and radiologists should be aware of anatomical alterations in this region when involved in diagnosis or imaging interpretation. The present report describes a well-developed muscle of the lateral compartment of the leg that inserted distally onto the talus and calcaneus. This muscle could be considered a variation of the so-called peroneus quartus muscle. To the authors’ knowledge this muscle variation has not been described as having an attachment onto the talus thus the term ‘peroneotalocalcaneus muscle’ is proposed.     

Thermosensitivity of muscle: high-intensity thermal stimulation of muscle tissue induces muscle pain in humans

Small-calibre afferent units responding to thermal stimuli have previously been reported to exist in muscle. The question as to whether these receptors in humans mediate subjective thermal sensations from muscle remains unresolved. The aims of the present study were to determine in humans whether intramuscular injection of warm and cold isotonic saline elicits temperature sensations, muscle pain or any other sensations. In 15 subjects, no thermal sensations assessed on a temperature visual analogue scale (VAS) could be detected with intramuscular injections of isotonic saline (1.5 ml) into the anterior tibial muscle at temperatures ranging from 8 to 48 °C. The same subjects recorded strongly increasing scores on a temperature VAS when thermal stimuli in the same intensity range were applied to the skin overlying the muscle by a contact thermode. However, i.m. isotonic saline of 48 °C induced muscle pain with peak scores of 3.2 ± 0.8 cm on a VAS scale ranging from 0 to 10 cm. Using the the McGill pain questionnaire a subgroup, of subjects qualitatively described the pain using the 'thermal hot' and 'dullness' word groups. Temperature measurements within the muscle during the stimulating injections showed that the time course of the pain sensation elicited by saline at 48 °C paralleled that of the intramuscular temperature and far outlasted the injection time. The present data show that high-intensity thermal stimulation of muscle is associated with muscle pain. High-threshold warm-sensitive receptors may mediate the pain following activation by temperatures of 48 °C or more. Taken together, the data indicate that thermosensation from a given volume of muscle is less potent than nociception.     

Role of nitric oxide in muscle regeneration following eccentric muscle contractions in rat skeletal muscle

We examined the role of nitric oxide (NO) in muscle repair and regeneration following repetitive eccentric contractions (ECC). A standardized exercise protocol was used to create eccentric contraction-induced injury to the left tibialis anterior muscle of 48 male Wistar rats (body wt 250–350 g), using a customized isokinetic test device and a bout of 40 ECCs under electrical stimulation. A nitric oxide synthase inhibitor, N(G)-nitro-l-arginine-methyl ester (l-NAME; 35 mg kg^?1 day^?1), was included in the diet for half the animals (n = 24) beginning 3 days prior to the ECC and continuing throughout the experiment, whereas the other half (n = 24) received a control diet. ECC/+l-NAME and ECC/?l-NAME were killed after the ECC protocol at 0, 1, 3 and 7 days (n = 6 on each day). An unexercised contralateral limb with and without l-NAME infusion served as a respective control muscle at each time point. Muscle NO content, skeletal muscle damage, leukocyte infiltration, calpain activity, and MyoD and myogenin expression were assessed. NO has both pro-inflammatory and anti-inflammatory properties, and several possible roles for NO in skeletal muscle damage have been postulated. NO content was greater in the ECC/?l-NAME group at all time points (p < 0.05) compared to ECC/+l-NAME. Additionally, significant differences in NO content were observed on day 0 (p < 0.05), and day 3 (p < 0.05), ECC/+l-NAME versus ECC/?l-NAME. One day following the bout of ECC, and NO levels were increased in the ECC/?l-NAME group. Three days following ECC, there was greater myofiber damage (measured by β-glucuronidase activity) and leukocyte invasion in the ECC/?l-NAME group as compared to the ECC/+l-NAME group. One day after ECC, calpain activity was significantly increased in ECC/?l-NAME compared with control muscles (p < 0.05). On days 3 and 7, Myo-D and myogenin gene expression was increased in both groups; however, the degree of regeneration was less in the ECC/+l-NAME-treated animals. These data suggest that NO dynamics have important implications in the regulation of various factors during skeletal muscle regeneration following damaging eccentric muscle contractions.     

Elevator muscle of the tendon of latissimus dorsi muscle

Muscular dispositions in the axilla acquire importance under certain surgical procedures that involve the axillary artery ligature. These supernumerary muscles make the approach to the axillary fossa and their content difficult. We dissected 108 formalized corpses from adult male individuals. The specimens belong to the topographic Anatomy Unit of the Faculty of Medicine, Universidad de La Frontera, Chile. In all dissections, a rare and infrequent muscular variation attributed to the presence of a elevator muscle at the dorsal part of the latissimus muscle on the right upper limb from an adult individual was found. This muscle was fusiform and originated at the coracoid process by a short tendon of cylindrical form inserted in the dorsal superior part of the tendon of the latissimus dorsi muscle. Muscular belly and tendons of origin and insertion were closely related to the brachial plexus and the axillar vessels that they crossed.     

Complement activation promotes muscle inflammation during modified muscle use

Modified muscle use can result in muscle inflammation that is triggered by unidentified events. In the present investigation, we tested whether the activation of the complement system is a component of muscle inflammation that results from changes in muscle loading. Modified rat hindlimb muscle loading was achieved by removing weight-bearing from the hindlimbs for 10 days followed by reloading through normal ambulation. Experimental animals were injected with the recombinant, soluble complement receptor sCR1 to inhibit complement activation. Assays for complement C4 or factor B in sera showed that sCR1 produced large reductions in the capacity for activation of the complement system through both the classical and alternative pathways. Analysis of complement C4 concentration in serum in untreated animals showed that the classical pathway was activated during the first 2 hours of reloading. Analysis of factor B concentration in untreated animals showed activation of the alternative pathway at 6 hours of reloading. Administration of sCR1 significantly attenuated the invasion of neutrophils (-49%) and ED1(+) macrophages (-52%) that occurred in nontreated animals after 6 hours of reloading. The presence of sCR1 also reduced significantly the degree of edema by 22% as compared to untreated animals. Together, these data show that increased muscle loading activated the complement system which then briefly contributes to the early recruitment of inflammatory cells during modified muscle loading.     

Nascent muscle fiber appearance in overloaded chicken slow-tonic muscle

The application of a weight overload to the humerus of chickens induces a hypertrophy of anterior latissimus dorsi (ALD) muscle fibers. This growth is accompanied by a rapid and almost complete replacement of one slow-tonic myosin isoform, SM-1, by another slow-tonic isoform, SM-2. In addition, a population of small fibers appears mainly in extrafascicular spaces and, concurrently, three additional myosin bands are detected by gel electrophoresis. Five antibodies against myosin heavy chain (MHC) isoforms were selected as immunocytochemical probes to determine the cellular location and nature of these myosins. The antibodies react with ventricular, fast skeletal muscle and either SM-1 or SM-2, or both the slow-tonic MHCs. The antifast and antiventricular antibodies react with myosin present in the 10-day embryonic ALD muscle but do not react with myosin in posthatch ALD muscle. The small fibers in overloaded muscle contain a myosin isoform characteristically expressed during the embryonic stage of ALD muscle development and therefore are named nascent myofibers. Some of the nascent myofibers do not react with the antibody to both slow-tonic MHCs, indicating the lack of the normal adult slow-tonic myosins which are expressed in 10-day embryos. In order to explore the origin of the nascent fibers, an electron microscopic study was performed. Stereological analysis of the existing fibers shows a stimulation of numbers and sizes of satellite cells. In addition, the volume occupied by nonmuscle and undifferentiated cells increases dramatically. Myotube formation with incipient myofibrils is seen in extrafascicular spaces. These data suggest that new muscle fiber formation accompanies hypertrophy in overloaded chicken ALD muscle, and the process may involve satellite cell migration.     

Inspiratory muscle training attenuates the human respiratory muscle metaboreflex

We hypothesized that inspiratory muscle training (IMT) would attenuate the sympathetically mediated heart rate (HR) and mean arterial pressure (MAP) increases normally observed during fatiguing inspiratory muscle work. An experimental group (Exp, n = 8) performed IMT 6 days per week for 5 weeks at 50% of maximal inspiratory pressure (MIP), while a control group (Sham, n = 8) performed IMT at 10% MIP. Pre- and post-training, subjects underwent a eucapnic resistive breathing task (RBT) (breathing frequency = 15 breaths min⁻¹, duty cycle = 0.70) while HR and MAP were continuously monitored. Following IMT, MIP increased significantly ( P < 0.05) in the Exp group (−125 ± 10 to −146 ± 12 cmH₂O; mean ± s.e.m. ) but not in the Sham group (−141 ± 11 to −148 ± 11 cmH₂O). Prior to IMT, the RBT resulted in significant increases in HR (Sham: 59 ± 2 to 83 ± 4 beats min⁻¹; Exp: 62 ± 3 to 83 ± 4 beats min⁻¹) and MAP (Sham: 88 ± 2 to 106 ± 3 mmHg; Exp: 84 ± 1 to 99 ± 3 mmHg) in both groups relative to rest. Following IMT, the Sham group observed similar HR and MAP responses to the RBT while the Exp group failed to increase HR and MAP to the same extent as before (HR: 59 ± 3 to 74 ± 2 beats min⁻¹; MAP: 84 ± 1 to 89 ± 2 mmHg). This attenuated cardiovascular response suggests a blunted sympatho-excitation to resistive inspiratory work. We attribute our findings to a reduced activity of chemosensitive afferents within the inspiratory muscles and may provide a mechanism for some of the whole-body exercise endurance improvements associated with IMT.     

Cytokeratins in smooth muscle cells and smooth muscle tumours

A keratin positive metastatic leiomyosarcoma in the lung, which resulted in diagnostic error, is reported. The results of additional studies of 17 benign and malignant leiomyogenic tumours with various keratin antibodies are presented and discussed in the light of recent bibliographical data.