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III. The deep layer of cervical fascia proper
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(lamina profunda fasciae colli propriae /глубокая пластинка собственной фасции шеи)
· This fascia is present only in the middle part of the neck and passes from the hyoid bone to the posterior border of the sternum and the clavicles.
· It forms the fascial sheaths for the infrahyoid muscles.
· The fascia fuses with the superficial layer of the cervical fascia proper along the omohyoid muscles and linea alba cervicalis.
· Between two layers of the cervical fascia proper there is the suprasternal space (spatium suprasternale /надгрудинное пространство), containing the superficial veins of the neck. Laterally this space communicates with the recessus lateralis – a blind space behind the inferior end of the sternocleidomastoid into which pus may penetrate.
IV. The endocervical fascia (fascia endocervicalis /внутришейная фасция)
· It encloses the organs located in the neck (larynx, trachea, thyroid gland, pharynx, oesophagus and the large vessels).
· This fascia consists of two layers:
- A visceral layer encloses each of these organs and forms a capsule for them.
- A parietal layer encloses all these organs and forms a sheath for the common carotid artery and the internal jugular vein.
· The space between the parietal and visceral layers of this fascia lies in front of the viscera and is therefore called the previsceral space (spatium previscerale /предорганное пространство), that in front of trachea, in particular, is called the pretracheal space (spatium pretracheale /предтрахеальное пространство). The later contains the isthmus of the thyroid gland and blood vessels.
· The pretracheal space extends into the anterior mediastinum.
V. The prevertebral fascia (fascia prevertebralis /предпозвоночная фасция)
· It covers anteriorly the deep muscles of the neck.
· The retrovisceral space (spatium retroviscerale /позадиорганное пространство) is between the endocervical and prevertebral fasciae. It continuous with the posterior mediastinum.
Topography of the neck
The neck is divided into four regions: posterior, lateral, the region of the sternocleidomastoid and anterior region.
· The posterior cervical region is behind the lateral border of the trapezius and is the nape, or nucha.
· The lateral cervical region is bounded in front by the sternocleidomastoid, below by the clavicle, behind by the trapezius. There are two triangles within lateral region:
- The omoclavicular triangle (trigonum omoclaviculare /лопаточно-ключичный треугольник) is bounded by the sternocleidomastoid in front, the inferior belly of the omohyoid above, the clavicle below.
- The omotrapezoid triangle (trigonum omotrapezoideum /лопаточно-трапециевидный треугольник) is bounded by the sternocleidomastoid in front, the inferior belly of the omohyoid below, the trapezius behind.
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· The sternocleidomastoid region corresponds to the projection of this muscle.
· The anterior cervical region is bounded posteriorly by the sternocleidomastoid, in front by the midline of the neck, above by the lower border of the mandible. There are three triangles within anterior region:
- The carotis triangle (trigonum caroticum /сонный треугольник) (transmitting the carotid artery) is bounded by the sternocleidomastoid posteriorly, the posterior belly of the digastric in front and above, the superior belly of the omohyoid in front and below.
- The submandibular triangle (trigonum submandibulare /поднижнечелюстной треугольник) (lodging the submaxillary gland) is bounded by the inferior border of the mandible above and two bellies of the digastric. There is Pirogov’s triangle (transmitting the lingual artery) within the submandibular triangle. It is bounded by the posterior border of the mylohyoid, intermediate tendon of the digastricus and the hypoglossal nerve.
- The omotracheale triangle (trigonum omotracheale /лопаточно-трахеальный треугольник) is bounded by the middle line of the neck medially, the sternocleidomastoideus behind and below, the superior belly of the omohyoid behind and above.
· A small area behind the mandibular angle and in front of the mastoid process is called the retromandibular fossa lodging the parotid gland.
· Between the anterior and middle scalene muscles is the interscalene space, bounded by the first rib below. It transmits the subclavian artery and the brachial plexus.
· In front of the anterior scalene muscle there is the antescalene space, transmitting the subclavian vein.
THE MUSCLES OF THORAX (musculi thoracis /мышцы груди)
Muscles related to the upper limb
Pectoralis major (m. pectoralis major /большая грудная мышца)
· Origin. From the sternum and the upper six costal cartilages and from the medial half of the clavicle.
· Insertion. The lateral lip of the intertubercular sulcus of the humerus.
· Actions. Adduction, flexion and medial rotation of the arm.
· Nerve supply. Medial and lateral pectoral nerves (brachial plexus).
Pectoralis minor (m. pectoralis minor /малая грудная мышца)
· Origin. The 3rd, 4th and 5th ribs.
· Insertion. The coracoid process of the scapule.
· Action. Depresses the tip of the shoulder.
· Nerve supply. Medial and lateral pectoral nerves (brachial plexus).
Serratus anterior (m. serratus anterior/передняя зубчатая мышца)
· Origin. The lateral surfaces of the upper eight ribs.
· Insertion. The medial border of the scapula.
· Actions. Protraction of the scapula and rotation so that the glenoid points upwards, thus helping in abduction of the upper limb. Helps to keep the scapula in contact with the chest wall.
· Nerve supply. Long thoracic nerve (brachial plexus).
Subclavius (m. subclavius /подключичная мышца)
· Origin. The cartilage of the first rib.
· Insertion. The inferior surface of the acromial end of the clavicle.
· Actions. It strengthens the sternoclavicular joint by the pulling the clavicle down and medially.
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· Nerve supply. Subclavius nerve (brachial plexus).
Autochthonous muscles
External intercostal muscles (mm. intercostales externi /наружные межрёберные мышцы)
· Origin. The inferior border of each rib. They descend anteriorly.
· Insertion. The superior border of the neighboring rib. Between the costal cartilages the muscles are replaced by a fibrous band with fibres lying in the same direction – external intercostal membrane (membrana intercostalis externa /наружная межрёберная мембрана).
· Actions. Raise the ribs.
Levatores costarum (mm. levatores costarum /мышцы, поднимающие рёбра)
· Origin. The transverse processes of the seventh cervical and thoracic (I-XI) vertebrae.
· Insertion. The angles of the neighboring ribs or they overlap one rib.
· Actions. Raise the ribs.
Internal intercostal muscles (mm. intercostales interni /внутренние межрёберные мышцы)
· Origin. The superior border of each rib. They ascend anteriorly.
· Insertion. The inferior border of the neighboring rib. Posteriorly these muscles reach only the costal angles and are further replaced by the internal intercostal membrane (membrana intercostalis interna /внутренняя межрёберная мембрана).
· Actions. Draw the ribs downwards.
Subcostales (mm. subcostales /подрёберные мышцы)
· These muscles are thin muscular bundles found on the inner surface of the lower part of the thoracic cage in the region of the costal angles. Their fibres are directed like the fibres of the internal intercostal muscles, but they overlap one or two rib.
· Actions. Draw the ribs downwards.
Transversus thoracis (m. transversus thoracis /поперечная мышца груди)
· Origin. The inner surface of the xiphoid process and the inferior part of the body of sternum.
· Insertion. The inner surface of the II-VI ribs.
· Actions. Draw the ribs downwards.
Nerve supply of the autochthonous muscles. Intercostal nerves.
Diaphragm (diaphragma /диафрагма)
The diaphragm forms the partition between the thoracic and abdominal cavity. It is flat dome-shaped muscle, covered above and below with fasciae and serous membranes.
· Origin.
- The costal part (pars costalis diaphragmatis /рёберная часть диафрагмы) originates from the inner surfaces of the lower six ribs.
- The sternal part (pars sternalis diaphragmatic /грудинная часть диафрагмы) originates from the back of the xiphoid process of the sternum.
- The lumbar part (pars lumbalis diaphragmatic /поясничная часть диафрагмы) originates from the right and left crura (crus dextrum, sinistrum /правая, левая ножка) which are attached, respectively, to the upper three and the upper two lumbar vertebrae and from the medial and lateral arcuate ligaments (lig. arcuatum mediale, laterale /медиальная, латеральная дугообразная связка) which bridge over the psoas major and quadratus lumborum.
· Insertion. The fibres (striated muscle) are inserted into the central tendon (centrum tendineum /сухожильный центр).
· The diaphragm has openings:
- The aortic hiatus (hiatus aorticus /аортальное отверстие) is between right and left crura and the spine. It transmits the aorta.
- The oesophageal hiatus (hiatus oesophageus /пищеводное отверстие) is just above and to the left of the aortic hiatus. It and transmits the oesophageus.
- The caval opening (foramen venae cavae /отверстие нижней полой вены) is in the central tendon. It transmits the inferior vena cava.
· There are two paired spaces – the sternocostal and lumbocostal triangles (trigonum sternocostale, lumbocostale /грудино-рёберный, пояснично-рёберный треугольник) between the corresponding parts of the diaphragma. They are covered by the pleura and endothoracic fascia above and by the endoabdominal fascia and peritoneum below.
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· Actions. The diaphragm is involved in respiration. When the muscle fibres contract, the diaphragm is lowered, thus increasing, the vertical dimension of the thorax. In the later stages of contraction, using the liver as a fulcrum it raises the lower ribs, thus increasing the width of the lower thorax. At the same time, it increases the intra-abdominal pressure and is thus used in expulsive efforts – defecation, micturition, parturition, etc.
· Nerve supply. Phrenic nerve (cervical plexus).
The fasciae of thorax
The superficial fascia (fascia superficialis /поверхностная фасция)
It is the part of the common superficial fascia of the body. The mammary gland is most important of all contents of this fascia. The fibrous septa given off by the fascia support the lobes of the gland, and the skin covering the gland.
The pectoral fascia (fascia pectoralis /грудная фасция)
It covers the muscles related with the upper limb. In the clavipectoral triangle it is called the clavipectoral fascia (fascia clavipectorale /ключично-грудная фасция).
The thoracic fascia (fascia thoracica /собственная грудная фасция)
It lines the outer surface of the thoracic cage and the external intercostal muscles.
The endothoracic fascia (fascia endothoracica /внутригрудная фасция)
It lines the inner surface of the thoracic wall.
Topography of the thorax
There are three triangles within pectoral region:
· The clavipectoral triangle (trigonum clavipectorale /ключично-грудной треугольник) is bounded by the clavicle and the superior border of the pectoralis minor.
· The pectoral triangle (trigonum pectorale /грудной треугольник) corresponds to the pectoralis minor.
· The subpectoral triangle (trigonum subpectorale /подгрудной треугольник) is bounded by the inferior borders of the pectoralis minor and pectoralis major and the anterior border of the deltoideus.
The lines of the thorax
· Theanterior median line passes along the middline of the sternum.
· The sternal line passes along the border of the sternum.
· The midclavicular line passes through the middle of the clavicle.
· The parasternal line passes through the middle between the sternal and midclavicular lines.
· The anterior axillar line passes through the anterior wall of the axillary fossa.
· The posterior axillary line passes through the posterior wall of the axillary fossa.
· The midaxillary line through the middle between the anterior and posterior axillary lines.
· The scapular line passes through the inferior angle of the scapule.
· The paravertebral line passes through the tubercles of the ribs.
· The posterior median line passes through the vertebral spinous processes.
THE MUSCLES OF Abdomen (musculi abdominis /мышцы живота)
All the muscles of the anterior abdominal wallserve to protect the viscera bytheir contraction, to produce movement and to increase the intra-abdominal pressure, as in defecation, coughing, parturition, etc.
External oblique (m. obliquus externus abdominis /наружная косая мышца живота)
· Origin. From the outer surfaces of the lower eight ribs to the iliac crest as far forward as the anterior superior spine.
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· Insertion. The free lower border forms the inguinal ligament (lig. inguinale /паховая связка) between the anterior superior iliac spine and the pubic tubercle. The muscle becomes aponeurotic and reaches the midline where it interdigitates with the opposite side to form the linea alba.The aponeurosis contributes to the anterior layer of the rectus sheath.
· Actions. Flexion of the spine, side flexion and rotation of the trunk – the rightexternal oblique produces rotation to the left.
Internal oblique (m. obliquus internus abdominis /наружная косая мышца живота)
· Origin. From the thoracolumbar fascia, the iliac crest and the lateral half of the inguinal ligament.
· Insertion. Into an aponeurosis which is attached to the costal margin, and at the linea semilunaris (linea semilunaris /полулунная линия) the aponeurosis is divided into anterior and posterior layers, thus contributing to the rectus sheath.
· Actions. Flexion of the spine, side flexion and rotation of the trunk – the rightinternal oblique produces rotation to the right.
Transversus abdominis (m. transversus abdominis /поперечная мышца живота)
· Origin. From the thoracolumbar fascia, the iliac crest and the lateral one third of the inguinal ligament. Also from the innersurfaces of the lower six ribs, interdigitating with the diaphragm.
· Insertion. The aponeurosis passes to the linea semilunaris contributing to the rectus sheath. The lower fibres help to form the inquinal falx.
· Actions. Most of the fibres are transverse and thus pull in and flatten the abdominal wall.
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