趾长屈肌的亚部化研究及其临床意义

目的　探讨趾长屈肌的亚部划分，为临床外科“半肌”移位手术提供解剖学基础。 方法　大体解剖法、肌构筑法、改良Sihler’s 染色法。 结果　①可依劈开趾长屈肌肌内腱板，把该肌分为胫侧和腓侧两个亚部；②胫侧亚部各构筑学值大于腓侧亚部；③两亚部存在单独神经支配。 结论　①趾长屈肌可分为胫侧亚部和腓侧亚部，两亚部有独立的神经支配；②趾长屈肌的两个亚部均为半羽肌，胫侧亚部产生的肌力大于腓侧亚部。     

家兔趾深屈肌肌构筑、肌内神经和运动终板分布

目的:探讨家兔趾深屈肌的肌构筑与肌内神经和运动终板分布的关系。方法:肌构筑法、改良Sihler s染色法、乙酰胆碱酯酶染色法。结果:家兔趾深屈肌为环羽肌。肌质量为(2.30±0.02)g,肌纤维长(1.00±0.01)cm,肌生理横切面积(2.17±0.12)cm2。肌的起端,神经干于腱板上方发出内侧和外侧两条初级支,初级支在肌内发出数目不等的次级支,继而向肌的深面和边缘发出终末支。有的次级支穿越腱板到达对侧。肌表面内、外两缘有线状排列的运动终板带,两带在肌止端相接,呈“V”形。结论:家兔趾深屈肌是环羽肌,倾向力量型设计;肌内神经分支存在越边支配;肌内神经和运动终板的分布与肌纤维排列有关;趾深屈肌有划分亚部的形态学特征。     

带蒂尺侧腕屈肌转位重建屈肘功能的应用解剖

在３１侧成人上肢标本上，按因管神经蒂转位重建屈肘功能要求，观测了尺侧腕屈肌及其血供和神经支配。尺侧腕屈肌的管蒂主要是尺侧返血管和尺血管的分支，以尺侧反血管分支为首选。支配尺侧腕屈肌的尺神经肌支长度多数不影响肌转位。按照保留尺侧腕屈肌主要血管和支配切断肌起止两端，经肌下和皮下道转位到肱二头肌正常解剖位置的术式设计，分析了血管神经蒂的选择和保护，讨论了术中应注意的问题和术式的优缺点。     

尺神经手部分支的显微解剖学研究及其意义

目的完善尺神经手部分支显微解剖结构特点及易卡压部位,探讨其临床意义。方法在头戴式放大镜下,对10具尸体标本20侧手部的尺神经分支进行纤维解剖,观察其走行及分布特点,测量相关数据。结果尺神经于腕关节近侧5 cm处发出尺神经手背支,穿过尺侧腕屈肌,经尺骨头尺侧进入腕背,分为桡侧分支和尺侧分支,桡侧分支又分为2支。尺神经在腕尺侧管内分为深、浅2支,浅支为感觉支,支配小指及环指尺侧半前面的皮肤和软组织;深支为肌支,分四段,发出分支支配大部分手肌。结论明确手部尺神经分支的走行、分布及其与周围结构的毗邻关系,对诊断手部神经卡压、定位探查手部尺神经分支损伤以及手术中避免破坏尺神经具有重要临床意义。     

尺动脉近段穿支蒂皮神经营养血管皮瓣的解剖基础

目的　为尺动脉近段穿支蒂前臂内侧皮神经营养血管皮瓣提供解剖学基础。 方法　在30侧动脉内灌注红色乳胶的成人上肢标本上解剖观测：①前臂内侧皮神经的走行与分布;②尺动脉近段穿支与前臂内侧皮神经营养血管间吻合关系。另在1侧新鲜标本上进行摹拟手术设计。 结果　①前臂内侧皮神经前支较粗长,与贵要静脉伴行,在前臂沿尺侧腕屈肌内侧缘或尺侧腕屈肌与掌长肌肌腱之间的浅筋膜中下行,分布于前臂掌面尺侧,远侧可达腕横纹;②营养血管为多节段、多源性,其中尺动脉近段穿支的位置相对恒定,自尺动脉起始后,先经指浅、深屈肌之间,后沿指浅屈肌与尺侧腕屈肌之间下行,在肱骨内上髁下8.7 cm处穿过深筋膜浅出至皮下组织中,并分出众多的细小血管与前臂内侧皮神经的神经旁和神经干血管链的分支密切吻合,在指浅屈肌与尺侧腕屈肌之间形成顺沿肌间隙和前臂内侧皮神经纵轴的血管丛。穿支蒂干长( 2.0±0.2) cm, 外径( 0.9±0.2) mm。 结论　可形成尺动脉近段穿支蒂前臂内侧皮神经营养血管皮瓣转位修复肘部软组织缺损。     

上肢神经肌支的显微解剖及其在痉挛性瘫痪治疗中的意义

目的：为寻求解除上肢痉挛性瘫痪的新途径提供理论依据。方法：在手术显微镜下,对43例成人上肢标本解剖观测,了解痉挛性脑瘫所致上肢痉挛性屈肘,旋前和屈腕畸形的主动肌神经肌支的来源,直径,可分离长度及发出部位。结果：肱二头肌肌支平均2．72支,来源于肌皮神经（97．5％）和正中神经（2．5％）,肱肌肌支平均2．74支,来源肌皮神经（80．5％）,其余分别来源于桡神经（15．3％）,正中神经（4．2％）,肱桡肌肌支平均1．77支,来源于桡神经,旋前圆肌肌支平均2．33支,来源于正中神经;尺侧腕屈肌肌支平均1．72支,来源于尺神经,它们的可分离长度分别为：肱二头肌肌支23．94mm,肱肌肌支21．63mm,肱桡肌肌支21．38mm,旋前圆肌肌支27．27mm,尺侧腕屈肌肌支21．70mm,神经肌支的横径分别为：0．99,1．00,0．86,0．84,0．83mm,在起始与进入肌门处的横径比较（t)检验无显著性差异（P＞0．05）。结论：神经肌支的横径考虑与神经所含数量有关,术中可在志始处选择性切断,切除的长度以术后不再出现神经再连续为度。     

关于尺神经在臂及前臂的分支及其与正中神经的吻合

共统计50个(男性、女性各25个)1—9岁儿量尸体共计100例上肢。观察尺神经在臂及前臂发出肌肢及肘关节支的情况以及尺神经与正中神经在前臂吻合的情况。 1.尺神经发出关节支至肘关节,关节支的数量是1—3支,其发出的部位有三:在肱骨内上髁以上发出的37例,占37％;在平肱骨内上髁处发出的36例,占36％;在肱骨内上髁以下发出的27例,占27％;由第一支起始点至肘关节囊的距离为0.2—1.8厘米。 2.尺神经发出肌支,以总干分支支配尺侧屈腕肌及屈指深肌的8例,占8％;支配屈指浅肌的9例,占9％;以总干分支支配尺侧屈腕肌及肘关节的14例,占14％;分别分支支配尺侧屈腕肌及屈指深肌的69例,占69％。其第一肌支发出的部位有三:在肱骨内上髁以上发出的七例,占7％;在平肱骨内上髁处发出的4例,占4％;在肱骨内上髁以下发出的89例,占89％。其最后肌支都在肱骨内上髁以下发出。第一肌支支配尺侧屈腕肌的80例,占80％;支配屈指浅肌的4例,占4％;以总干分细支支配尺侧屈腕肌及屈指深肌的1例,占1％;以总干分细支支配尺侧屈腕肌及屈指浅肌的1例,占1％;以总干分细支支配尺侧屈腕肌与肘关节的14例,占14％。最后肌支支配尺侧屈腕肌的18例,占18％;支配屈指深肌的77例,占77％,支配屈指浅肌的2例,占2％;以总干分两支分别支配屈指浅肌及尺侧屈腕肌的1例,占1％;以总干分两支分别支配屈指深肌及尺侧屈腕肌的1例,占1％;以总干分为两支分别支配屈指浅肌及屈指深肌的1例,占1％。至各肌的肌支数量是1—4支。 3.100例上肢中发现尺神经与正中神经之间在前臂前面有吻合的30例,占30％,较高于国外作者统计的百分率。其中对称的9例,不对称的21例。吻合的部位都是在屈指浅肌尺侧头与屈指深肌近侧端之间,或在屈指深肌之内;根据吻合支结合的形态特征可将吻合区分为襻型(17例)、“V”字型(4例)、“Y”字型(3例)及直綫型(6例)四种。     

三角肌神经入肌点定位及肌内神经分布的研究

目的　揭示三角肌神经入肌点和肌内神经分支分布 ,为其临床应用提供较为详尽的形态学资料。方法　①用经甲醛固定 2年以上的成人尸体 (2 0～ 5 0岁 ) 12具 (男 9,女 3)共 2 4侧。以肩峰后角为骨性标志 ,测量三角肌各亚部神经支入肌点的位置。②用经甲醛固定 1年以内的童尸 3具 (3～ 10岁 )及成人尸体 2具 (2 0、4 0岁 )完整取下三角肌 ,采用Sihler′s肌内神经染色法观察肌内神经分支分布。结果　①三角肌各亚部神经入肌点的体表投影 :三角肌前亚部、中亚部、后亚部的神经入肌点分别在距肩峰后角下方 (5 7± 0 7)cm、(5 9± 0 8)cm、(4 8± 0 5 )cm处的水平线上 ,距三角肌前缘外后方 (3 6± 0 4 )cm处及距三角肌后缘外前方 (3 5± 0 6 )cm、(2 3± 0 3)cm处 ,上述三点均在肌的中 1/3部。②肌内神经分布 :三角肌前、后亚部的肌内神经支在肌内为直接横过肌纤维中部 ,沿途再发出分支与肌纤维并行走行 ;而中亚部肌内神经支在各个羽内 ,与肌纤维相交 ,行向短肌纤维的起止端。结论　①三角肌的神经入肌部位及入肌形式与该肌的形态和功能有关联 ;②三角肌的肌内神经分支分布可能与该肌的肌纤维长度及肌纤维型有关 ;③三角肌中亚部的肌内神经吻合网较宽而致密 ,推测有着更精细的神经调节。     

人背阔肌的亚部化研究

目的为背阔肌亚部肌移植的临床应用提供形态学资料。方法用大体解剖法和Sihler′s肌内神经染色法对35具尸体背阔肌行亚部化研究。结果(1)胸背神经主要(91.43%)发出两支一级分支,即内上支和外下支,其中内上支发出2~3支二级神经支,外下支发出3~5支二级神经支;二级神经支在肌内发出树枝状分支,并在肌中部构成网格状的神经分支密集区。(2)背阔肌内上部和外下部的肌质部表面积分别为134.33±16.82cm2、226.93±32.05cm2。结论背阔肌有较恒定的胸背神经分支分布,可分为两个亚部:内上部和外下部。外下部的肌质部表面积是内上部的1.69倍。     

小鱼际肌肌内神经和肌梭密度分布

目的揭示小鱼际肌肌内神经和肌梭密度的分布规律。方法对成年20具尸体(40例)小鱼际标本用改良Sihler肌内神经染色法和苏木精-伊红(HE)染色法。结果小鱼际肌肌外神经干长0.49～1.64 cm,从肌起端深面入肌。小指展肌内尺侧和桡侧有独立的神经支配,可分为两个神经肌亚部;小指短屈肌的肌内神经干斜行穿越肌实质中央;小指对掌肌内神经吻合形式多样,"U"型吻合更明显。3块肌的桡侧部神经分支分布密集。小指对掌肌肌梭密度最高为(19.33±2.72)个/g;小指短屈肌其次,有(15.79±1.33)个/g;小指展肌最少,为(12.86±1.69)个/g。结论三块肌桡侧部更多地参与精细调节;肌块越小,肌梭密度越高。     

Electromechanical delay in human skeletal muscle under concentric and eccentric contractions

Summary In contraction of skeletal muscle a delay exists between the onset of electrical activity and measurable tension. This delay in electromechanical coupling has been stated to be between 30 and 100 ms. Thus, in rapid movements it may be possible for electromyographic (EMG) activity to have terminated before force can be detected. This study was designed to determine the dependence of the EMG-tension delay upon selected initial conditions at the time of muscle activation. The rigth forearms of 14 subjects were passively oscillated by a motor-driven dynamometer through flexion-extension cycles of 135 deg at an angular velocity of 0.5 rad/s. Upon presentation of a visual stimulus the subjects maximally contracted the relaxed elbow flexors during flexion, extension, and under isometric conditions. The muscle length at the time of the stimulus was the same in all three conditions. An on-line computer monitoring surface EMG (Biceps and Brachioradialis) and force calculated the electromechanical delay. The mean value for the delay under eccentric condition, 49.5 ms, was significantly different (p<0.05) from the delays during isometric (53.9 ms) and concentric activity (55.5 ms). It is suggested that the time required to stretch the series elastic component (SEC) represents the major portion of the measured delay and that during eccentric muscle activity the SEC is in a more favorable condition for rapid force development.     

Muscle hypertrophy in bodybuilders

Summary Muscle biopsy samples were obtained from m. vastus lateralis and m. deltoideus of three high caliber bodybuilders. Tissue specimens were analysed with respect to relative distribution of fast twitch (FT) and slow twitch (ST) fiber types and different indices of fiber area. In comparison to a reference group of competitive power/weight-lifters the following tendencies were observed: the percentage of FT fibers was less, mean fiber area was smaller and selective FT fiber hypertrophy was not evident. Values for fiber type composition and fiber size were more similar to values reported for physical education students and non-strength trained individuals. The results suggest that weight training induced muscle hypertrophy may be regulated by different mechanisms depending upon the volume and intensity of exercise.     

Effect of low frequency fatigue on human muscle strength and fatigability during subsequent stimulated activity

Summary Fatiguing contractions of the adductor pollicis muscle were produced by intermittent supramaximal stimulation of the ulnar nerve in a set frequency pattern, in six normal subjects. At the end of an initial fatiguing contraction series, low frequency fatigue (LFF) had been induced and persisted at 15 min of recovery. Stimulated fatiguing activity was then repeated in an identical fashion to the initial series. At high frequencies, declines in force were similar for both series. At low frequencies, declines in force were greater during the second series despite similar changes in compound muscle action potential amplitude. This confirmation that LFF persists during subsequent stimulated activity, and reduces low but not high frequency fatigue resistance, suggests that the impaired endurance of fatigued muscle during voluntary activity primarily results from peripheral changes at low frequency. These findings also have implications for therapeutic electrical stimulation of muscle.     

Contractile and histochemical properties of regenerating cross-transplanted fast and slow muscles in the rat

Summary The soleus (SOL) or extensor digitorum longus (EDL) muscles of month-old rats were denervated for 14 days and then cross-transplanted so that the fast muscle was placed into the bed of the slow muscle and vice versa. At 17, 30, 60, and 90 days the transplants were tested for certain contractile and histochemical properties. By 90 days the cross-transplanted SOL showed complete conversion of the full contraction time and nearly complete conversion of the half relaxation time to those of the normal EDL. In contrast, the contraction and relaxation times of the cross-transplanted EDL became considerably slowed, but did not attain the values of the normal SOL. Histochemical staining for ATPase and SDH activity demonstrated similar transformations of fiber types. The degree of transformation of twitch and histochemical characteristics in cross-transplanted muscles was greater than the values reported after cross-innervation of the same muscles. The cross-transplantation model has certain advantages over nerve cross-union experiments because the cross-transplanted muscle is placed in the normal functional environment of the other muscle.Supported by grants from the Muscular Dystrophy Associations of America and a scientific exchange between the Academies of Sciences of Czechoslovakia and the United States.     

Changes in stiffness induced by hindlimb suspension in rat soleus muscle

Soleus muscle atrophy was induced by hindlimb suspension of rats for 3 weeks with the intention of inducing a relative increase in the percentage of fast twitch fibres and assessing modifications in muscle stiffness. A method of dual controlled releases was used to obtain tension/extension curves and force/velocity relationships characterizing the mechanical behaviour of the soleus. Fibre typing was achieved by myofibrillar adenosine 5-triphosphatase staining. Results showed that hindlimb suspension decreased the percentage of slowtwitch fibres (–31%) to the profit of fast-twitch fibres (+370%) and intermediate fibres (+255%). This led to an increase in maximal shortening velocity. Tension/extension curves indicated a decrease in soleus stiffness after 3 weeks of unloading. Changes in elastic properties are interpreted in terms of modifications occurring in the active part and the passive part of the so-called series elastic component. These changes also suggest that the parameters derived from a twitch are inappropriate to account for modifications in speed-related properties of muscle.     

The relationships among peak torque, mean power output, mechanomyography, and electromyography in men and women during maximal, eccentric isokinetic muscle actions

The purpose of the present investigation was to examine the velocity-related patterns of peak torque (PT), mean power output (MP), mechanomyographic (MMG) amplitude, and electromyographic (EMG) amplitude of the vastus lateralis (VL) muscle in men and women during maximal, eccentric isokinetic muscle actions of the leg extensors. Eight women [mean (SD)] [aged 23 (3) years] and seven men [aged 23 (2) years] volunteered for this investigation. Their PT was measured on a calibrated dynamometer at randomly ordered velocities of 30, 90, and 150°·s^–1. A piezoelectric MMG recording sensor was placed between bipolar surface EMG electrodes (Ag-AgCl) over the VL muscle. Their MP was determined using the dynamometer software. The results indicated no sex-related differences (P>0.05) for the patterns of PT, MP, MMG amplitude, or EMG amplitude across velocity. The normalized values for MP and MMG amplitude increased (P<0.05) from 30 to 150°·s^–1 (30°·s^–1<90°·s^–1<150°·s^–1), while PT and EMG amplitudes remained unchanged across velocity. The results indicated close associations between the velocity-related patterns of MP and MMG amplitudes as well as PT and EMG amplitudes. Thus, MMG amplitude reflected the velocity-related changes in muscle power output, but not torque production, while EMG amplitude reflected torque production, but not muscle power output. During maximal, eccentric isokinetic muscle actions, EMG and MMG signals provided unique information regarding the electrical and mechanical aspects of muscle strength and power. Electronic Publication     

Regeneration in grafts of normal and denervated rat muscles

Summary The soleus or extensor digitorum longus muscles of young rats were freely grafted into the bed of the corresponding contralateral muscle. The grafts were of normal muscle or muscles which had been denervated for 14 days. Grafts of normal muscle were characterized by little or no contractile activity for the first 2–4 days after transplantation. In contrast, denervated grafts contracted weakly, but consistently, throughout this early period. The patterns of contraction were complex. In early transplants, the contractions were due entirely to surviving muscle fibers in the graft, and the contractile characteristics were those of denervated muscle fibers. After the first week, contractions of newly regenerating muscle fibers within the grafts were superimposed upon and later took over those from the fibers that survived the original transplantation. The contraction time approached those of the normal soleus or extensor muscles during the second month after grafting, and the grafts contracted like fast or slow muscles.     

Mechanical influence of the extrafusal muscle on the static behaviour of deefferented primary muscle spindle endings in cat

Summary In 16 anesthetized cats 24 afferents of deefferented primary muscle spindle endings from the extensor digitorum longus muscle (EDL) were functionally isolated and their sensitivity to static stretches was tested. Each spindle was carefully located within the EDL using direct focal stimulation. Muscle spindle endings with poor static length sensitivity of stretch were always found in the most peripheral parts of the muscle fibre bundles, near to the aponeurotic and tendineous insertions. Endings having good static sensitivity to stretch were exclusively found in more central portions of the muscle fibre bundles. Using a photographic method, the alterations in the distance between designated points on the muscle surface ware measured during maintained muscle stretch. Only medial portions were markedly extended, whereas little or no increases in length occurred in peripheral parts of the muscle fibre bundles.Quantitatively, a direct relationship was found between the lengthening of those muscle portions, in which the muscle spindles were localized, and the receptors' sensitivity to maintained stretch.Preliminary reports of some of the results were given at the 1. Wissenschaftliche Tagung der Deutschen Gesellschaft für medizinische Physik (Rieboldet al., 1970; Robrechtet al., 1970) and at the Muscle-Spindle Symposium of the Anatomical Society of Great Britain and Ireland, April 4–6, 1974, at the University of Durham (Henatschet al., 1974). The results were presented in more detail in Meyer-Lohmann's Habilitationsschrift (1972).Supported by a grant from the Deutsche Forschungsgemeinschaft (Schwer-punktprogramm Rezeptorphysiologie).     

Effects of resistance exercise combined with vascular occlusion on muscle function in athletes

The effects of resistance exercise combined with vascular occlusion on muscle function were investigated in highly trained athletes. Elite rugby players (n=17) took part in an 8 week study of exercise training of the knee extensor muscles, in which low-intensity [about 50% of one repetition maximum] exercise combined with an occlusion pressure of about 200 mmHg (LIO, n=6), low-intensity exercise without the occlusion (LI, n=6), and no exercise training (untrained control, n=5) were included. The exercise in the LI group was of the same intensity and amount as in the LIO group. The LIO group showed a significantly larger increase in isokinetic knee extension torque than that in the other two groups (P<0.05) at all the velocities studied. On the other hand, no significant difference was seen between LI and the control group. In the LIO group, the cross-sectional area of knee extensors increased significantly (P<0.01), suggesting that the increase in knee extension strength was mainly caused by muscle hypertrophy. The dynamic endurance of knee extensors estimated from the decreases in mechanical work production and peak force after 50 repeated concentric contractions was also improved after LIO, whereas no significant change was observed in the LI and control groups. The results indicated that low-intensity resistance exercise causes, in almost fully trained athletes, increases in muscle size, strength and endurance, when combined with vascular occlusion. Electronic Publication     

Responses of old men to repeated bouts of eccentric exercise of the elbow flexors in comparison with young men

A bout of eccentric exercise confers protection against subsequent bouts of the same exercise. This study investigated whether the protective effect would be produced similarly between old and young adults. Eight old men (70.5 ± 4.1 years) and ten young men (20.4 ± 2.0 years) performed two bouts of eccentric exercise of the elbow flexors (six sets of five eccentric actions) separated by 4 weeks. Changes in maximal isometric strength, range of motion (ROM), upper arm circumference (CIR), plasma creatine kinase (CK) activity, myoglobin (Mb) concentration, and muscle soreness (SOR) before, immediately after, and 1, 24, 48, 72 and 96 h following exercise were compared between bouts, and between groups by a two-way repeated measures ANOVA. Changes in the measures following the first bout were significantly (P < 0.05) smaller for the old than the young group. The young group showed significantly (P < 0.05) smaller changes in all measures following the second bout than the first bout; however, the old group had the protective effect only for ROM, Mb, and SOR. The magnitude of the effect observed for ROM and Mb concentration in the old group was significantly (P < 0.05) smaller compared with that of the young group. These results suggest that the protective effect conferred by the first bout was less for the old than the young group. This may be due to the less muscle damage after the first bout in the old subjects, but it is also possible that the protective effect of old adults does not last as long as that of young adults.