Myology 肌学

Section 1. Introduction 总论 全身肌由于构造不同可分为 smooth m.平滑肌 cardiac m.心肌 skeleton m.骨骼肌 skeletal muscle具有收缩的特性，是运动系统的动力部分，其收缩受神经支配，接受人的意志控制，故称voluntary m.随意肌。 全身有600余块肌，占体重40%。 每块肌都是一个器官：有一定形态、构造，有血管、淋巴管，受神经支配，执行一定功能。

Ⅰ. Shape and structure of the muscle 肌的形态和构造 1. Classification long m. 长肌 short m .短肌 flat m. 扁(阔)肌 orbicular m. 轮匝肌

1.Classification Acording the position of the muscles may be divided into M.of head 头肌 M.of neck 颈肌 M. of trunk 躯干肌 M.of limbs四肢肌 m. of back 背肌 m. of thorax胸肌 m. of abdomen 腹肌 diaphragm 膈

2. Structure muscle belly 肌腹 tendon 肌腱： aponeurosis 腱膜 二腹肌 腱膜 腱划

Ⅱ. Origin and insertion 肌的起、止 1、起于一块骨，止于另一块骨,跨过一个或多个关节。     2、 Origin起点（定点）、 insertion止点（动点），起止点可互换。    3、肌在关节周围配布的方式和多少与关节的运动类型密切相关。沿一个运动轴周围一般配布相对应的两组肌。    agonist 原动肌、 synergist 协同肌、 antagonist 拮抗肌 fixator 固定肌、

Ⅲ. Name of muscles 肌的命名 Location of the muscle. Shape of the muscle. Size of the muscle Direction of muscle

Ⅳ. Accessory structure 辅助结构 Ⅰ) fascia 筋膜 1、 superficial fascia 浅筋膜 位于真皮之下，又称皮下筋膜， 包被全身，由疏松结缔组织构成，富含脂肪。内有浅动脉、浅静脉、皮神经和浅淋巴管穿行。

2、 deep fascia 深筋膜： 又称固有筋膜，致密结缔组织构成，位于浅筋膜深面，包被体壁、四肢的肌和血管神经等。形成肌间隔、血管神经鞘 Ⅱ） synovial bursa 滑膜囊 ：为封闭的结缔组织囊，位于肌腱与骨面接触处。    

Ⅲ）Tendinous sheath 腱鞘 : 包围在肌腱外的鞘管，存在于腕、踝、手指和足指处。 fibrous layer 纤维层、 Synovial layer 滑膜层 或 synovial sheath of tendon 腱滑膜鞘 Viscerasl layer 脏层 Parietal layer 壁层 腱系膜

Section2 The muscles of head and neck 头肌和颈肌

Ⅰ. The muscles of head 头肌

一、Muscles of head Facial muscles 面肌: includ Epicranius 颅顶肌 (or occipitofrontalis) 枕额肌 Frontal belly 额腹 Occipital belly 枕腹 Galea aponeurotica 帽状腱膜 Orbicularis oculi 眼轮匝肌 Buccinator 颊肌 Orbicularis oris 口轮匝肌 Nasalis 鼻肌

Frontal belly of occitofrontalis orbicularis oculi Levator labii superioris提上唇肌 Levator anguli oris 提口角肌 Depressor labii inferioris降下唇肌 Orbicularis oris Depressor anguli oris降口角肌

（二） masticatory muscles 咀 嚼 肌 masseter 咬 肌 ： Origin－inferior border and medial surface of zygomatic arch Insertion－lateral surface of ramus of mandible and angle of mandible temporalis 颞 肌 ： Origin－temporal fossa Insertion－coronoid process of mandible action： masseter, temporalis --- elevates mandible— close the mouth

（二） masticatory muscles咀 嚼 肌 medial pterygoid 翼内肌 ： lateral pterygoid 翼外肌 ： action： medial pterygoid --- elevates mandible—close the mouth lateral pterygoid ：pull the head of mandible forwards--- open the mouth

Ⅱ. Muscles of neck 颈肌

Origins: manubrium and medial1/3 of clavicle （一）颈浅层肌和颈外侧肌 Platysma 颈阔肌 Sternocleidomastoid 胸锁乳突肌 Origins: manubrium and medial1/3 of clavicle Insertion: mastoid process of temporal bone; Actions: acting alone, the head is inclined ipsilateral and the face is rotated to opposite side; acting together, they extend the head.

（二）颈前肌 舌骨上肌群 digastric二腹肌 Mylohyoid 下颌舌骨肌 Stylohyoid 茎突舌骨肌 1、suprahyoid muscles 舌骨上肌群 Anterior belly 前腹 Posterior belly 后腹 digastric二腹肌 Mylohyoid 下颌舌骨肌 Stylohyoid 茎突舌骨肌 Geniohyoid 颏舌骨肌 Action: elevate (raise) hyoid bone and depress mandible.

（二）颈前肌 2、infrahyoid muscles 舌骨下肌群 sternohyoid 胸骨舌骨肌 omohyoid 肩胛舌骨肌 sternothyroid 胸骨甲状肌 Thyrohyoid 甲状舌骨肌 Action: depress hyoid or larynx

颈深部肌 scalene fissure 斜角肌间隙： （三）The deep cervical m. 可分为内、外两群 1、lateral goup scalenus anterior 前斜角肌 scalenus medius 中斜角肌 scalenus posterior 后斜角肌 scalene fissure 斜角肌间隙： it is bounded by the scalenus anterior and medius and first rib ，it contains the subclavian a and brachial plexus. 2、medial group： longus colli 颈长肌 longus capitis 头长肌

section 3 The muscles of trunk 躯干肌

Ⅰ. The muscles of back 背肌

1、superficial group （ 1）Trapezius 斜方肌 a large, triangular m. lying on the back of the neck and thorax; Origin: external occipital protuberance, superior nuchal line, ligamentum nuchae, the spinous processes of 7th cervical vertebrae and all thoracic vertebrae; Insertion: lateral 1/3 of clavicle, acromion and spine of scapula.

1、superficial group （ 1）Trapezius 斜方肌 Action： raises, descends, and rotates the scapula and extends the head. 使肩胛骨向脊柱靠拢；上部肌束可上提肩胛骨；下部肌束使肩胛骨下降。如果肩胛骨固定，一侧肌收缩使颈向同侧屈、脸转向对侧，两侧同时收缩可使头后仰。

1、superficial group （2）Latissimus Dorsi 背阔肌 It is a largest and triangular m. lying the back and lateral wall of thorax; Origins: the spinous processes of lower 6 thoracic vertebrae and all lumbar vertebrae; Insertion: inserted into the floor of the intertubercular sulcus Action: Extend, adduct， and rotate the shoulder joint medially 当上肢上举被固定时，可 引体向上。 Latissimus dorsi 背阔肌

（3）levator scapulae 肩胛提肌 1、superficial group （3）levator scapulae 肩胛提肌 origin：the transverse processes of the upper 4 cervical vertebrae; insertion：superior angle of scapula. Action：raise the scapula. Levator scapulae Rhomboideus （4）rhomboideus 菱形肌 Lies deep to the trapezius，可拉肩胛骨向脊柱靠拢。

2、The deep group Erector Spinae 竖脊肌 Splenius 夹肌 position： It lies in the vertebral groove on each side of vertebral spines; Action：extend the spinal column and head 使脊柱后伸和仰头。 Splenius 夹肌 position：位于斜方肌深面， Action： 单侧收缩，可使头转向同侧， 两侧收缩使头后伸。

3. Thoracolumbar facia：胸腰筋膜 指在竖脊肌周围的筋膜，可分为三层： Superficial layer：竖脊肌后面； Middle layer ：分隔竖脊 肌 和腰方肌； Deep layer：覆盖在腰方 肌前面

Ⅱ. The muscles of thorax 胸肌

1. Extrinsic muscles Pectoralis major Pectoralis minor Serratus anterior

Pectoralis major 胸大肌 Origin: medial half of clavicle,sternum,1th-6th costal cartilages. Insertion: crest of greater tubercle of humerus. Action: flexes, adducts and rotates arm medially; arm fixed, elevates trunk; elevates ribs 1-6,aidding in forced inspiration.

Pectoralis minor 胸小肌 Origin: 3rd-5th ribs Deep to the pectoralis major Origin: 3rd-5th ribs Insertion: coracoid process of scapula Action: Draw the scapula forwards and downwards,when the scapula is fixed it helps the inspiration(by elevation the ribs)

Serratus anterior 前锯肌 It overlies the laeral wall of thorax Origin: external surfaces of the upper 8~9 ribs Insertion: medial border of scapula Action: holds the scapula against the chest wall；Pulls the scapula forwards in throwing and pushing.

Intercostales externi 肋间外肌 2. Intrinsic muscles Intercostales externi 肋间外肌 Origin: lower border of rib Insertion: upper border of rib below origin external intercostals membrane 肋间外膜. Action: elevate ribs adding in forced inspiration

Intercostales interni 肋间内肌 Origin: upper border of rib； Insertion: lower border of rib above origin Replaced posteriorly by internal intercostals membrane. Action: depress ribs for forced expiration

Ⅲ. Diaphragm 膈 (1) Position and division: Sternal part: Costal part: dome-shaped between thorax and abdomen, consists of Central tendon 中心腱 muscular part 肌部 Sternal part: Costal part: Lumbar part: arises by left and right crus from upper 2-3 lumbar vertebrae Insertion: central tendon

③ Vena caval foramen腔静脉孔 (2) Openings of diaphragm ① Aortic hiatus 主动脉裂孔 at the level of 12th thoracic vertebra, the thoracic aorta and thoracic duct pass through it inferior vena cava T8 ② Esophageal hiatus 食管裂孔 at the level of 10th thoracic vertebra, the esophagus and vagus n. pass throught it T10 esophagus thoracic aorta T12 ③ Vena caval foramen腔静脉孔 at the level of 8th thoracic vertebra, inferior vena cava through it

(3) Action Contraction: the dome moving downward, increases the volume of thoracic cavity which results in inspiration. Relaxation: the dome returns to the former position, reduces the volume of the thoracic cavity, resulting in expiration.

(2) Weak areas: triangular spaces without muscular tissue Lumbocostal triangle 腰肋三角 between costal and lumbar parts. Sternocostal triangle 胸肋三角: between costal and sternal parts.

Muscles of abdomen Anterolateral group Obliquus externus abdominis 腹外斜肌 Obliquus internus abdominis 腹内斜肌 Transversus abdominis 腹横肌 Rectus abdominis 腹直肌

Obliquus externus abdominis 腹外斜肌 Origin: Arises from the lower 8 ribs, and the muscular fibers run obliquely from the superolateal to the inferomedial, the anterior part of the m. change gradually into aponeurosis, which pass over the rectus Abdominis; insertion: Linea alba 白线 .

Obliquus externus absominis 腹外斜肌 Structures formed by aponeurosis of this m. include： Inguinal ligament 腹股沟韧带 Superficial inguinal ring Superficial inguinal ring 腹股沟浅环 －triangular-shaped hiatus above pubic tubercle Lacunar ligament 腔隙韧带 Lacunar ligament

Obliquus internus abdominis 腹内斜肌 Origin: thoracolumbar fascia 胸腰筋膜 , iliac crest and the lateral half of the ingunal lig. Insertion: Linea alba 白线 The muscular fibers run upwards and forwards, and become the aponeurosis close the lateral border of the rectus abdominis. Its aponeurosis divided into two layers to inclose the rectus abdominis.

Transversels abdominis 腹横肌 is the deepest one of the three flat abdominal m. Origin: it arises from the costal cartilages of the lower 6 ribs，the thoracolumbar fascia , the iliac crest and the lateral 1/3 of the ingunal lig. , Insertion: Linea alba 白线 The muscular fibers run transversly ,and pass deep to rectus abdominis.

Transversels abdominis 腹横肌 Inguinal falx(conjoined tendon) 腹股沟镰or 联合腱: is a common aponeurosis joined by obliquus internus abdominis腹内斜肌 and transverse abdominis腹横肌, it turns downwards to insert the pubic crest and pecten pubis耻骨梳. Cremaster 提睾肌: around the spermatic cord and testis

The Sheath of rectus abdominis 腹直肌鞘 Anterior layer－ formed by the aponeurosis of obliquus externus abdominis ； anterior leaf of aponeurosis of obliquus internus abdominis Posterior layer：formed by posterion leaf of aponeurosis of obliquus internus abdominis ； aponeurosis of transverses abdominis

The Sheath of rectus abdominis 腹直肌鞘 arcuate line 弓状线 或semicircular line 半环线 at about 4-5cm below the umbilicus脐, the lower free border of the posterior layer of the sheth present arcuated. Below this line the rectus abdominis in contact with transverse fascia directly.

Linea alba 白线 －tendinous raphe between right and left rectus abdominis from xiphoid process to pubic symphysis.

The functions of the four pairs of muscles Support and protect the abdominal viscera Maintain and increase intra-abdominal pressure, aid in vomiting, coughing, sneezing, defecation, urination and childbirth. Flex, lateral flex, and rotate vertebral column

Posterior group Quadratus lumborum 腰方肌 Psoas major 腰大肌

Inguinal canal 腹股沟管 Position: oblique passage about 4cm long, and passes downwards and medially, it lies parallel to, and immediately above medial half of inguinal lig. It has two openings and four walls.

Four walls Anterior wall Aponeurosis of obliquus externus abdominis Obliquus internus abdominis (lateral third of wall)

Roof－ lower fibers of obliquus internus and transversus abdominis Post wall — Transverse fascia ； Inguinal flax medially Roof－ lower fibers of obliquus internus and transversus abdominis Floor－inguinal ligament．

Two openings Superficial inguinal ring 腹股沟浅环 Deep inguinal ring 腹股沟深环 －defect in transverse fascia，lies at about 1.5cm above midpoint of inguinal ligament

Structures passing through the inguinal canal Male: Spermatic cord 精索 female: Round ligament of uterus 子宫圆韧带