Dorsal surface of the upper limb

SDU. SDU. LIZHENHUALIZHENHUA

Dorsal surface of the upper limb

山东大学医学院解剖教研室李振华


The Muscles of Back

Superficial group

Trapezius 斜方肌

Levator scapulae 肩胛提肌

Rhomboid minor 小菱形肌

Rhomboid major 大菱形肌

Latissimus dorsi 背阔肌

Thoracolumbar fascia

胸腰筋膜


The Muscles of Back

Deep group Splenius 夹肌 Erector spinae 竖脊肌


Major Muscles of BackTrapezius 斜方肌 Origin: superior nuchal line, external oc

cipital protuberance, ligamentum nuchae and spinous processes of seventh cervical and all thoracic vertebrae

Insertion: lateral third of clavicle, acromion, and spine of scapular

Acton: upper fibers elevate scapula, lower fibers depress scapula; if scapula is fixed, one side acting along, draws head toward the same side, and turn face to opposite side; both sides together, draw head directly backward

Nerve supply: accessory nerve ( craⅪnial nerve)


Major Muscles of Back

Latissimus dorsi 背阔肌 Origin:

Spinous processes of lower six thoracic and all lumbar vertebrae

Median sacral crest Posterior part of iliac crest

Insertion: floor of intertubercular groove of humerus.

Action: trunk fixed, extends, adducts and medially rotates arm ; arm fixed, elevates trunk.

Nerve supply: thoracodorsal nerve


Thoracolumbar Fascia 胸腰筋膜

Posterior layerMiddle layer

Anterior layer


Trapezius

Deltoid

Ausculatory triangle

Latissimus dorsiThoracolumbar fascia

Levator scapular

Rhomboideus

Inferior lumbar triangle


Superior lumber triangle腰上三角


The Muscles of shoulder

Deltoid 三角肌 Supraspinatus 冈上肌 Infraspinatus 冈下肌 Teres minor 小圆肌 Teres major 大圆肌 Subscapularis 肩胛下肌


Deltoid 三角肌

Origin: lateral third of clavicle, acromion, and spine of scapula

Insertion: deltoid tuberosity of humerus Action: abducts the arm ， anterior fibers f

lex and medially rotate arm; posterior fibers extend and laterally rotate arm

Nerve supply: axillary nerve


Teres major 大圆肌 Origin: dorsal surface of inferior angl

e of scapula Insertion: crest of lesser tubercle of

humerus Action: medially rotates and adducts

arm Nerve supply: subscapular nerve


Contents of posterior osseofascial compartment of the arm

Muscle: Triceps brachii 肱三头肌

Nerve supply to the muscle: Radial nerve

Blood supply: deep brachial a. ulnar collateral a.

Structures passing through the compartment:

radial nerve ulnar nerve


Triceps brachii 肱三头肌

Origin: Long head from infraglenoid tubercle of

scapula lateral head from above the spiral groo

ve medical head from below the spiral gro

ove Insertion: olecranon of ulna Action: extends elbow joint, long hea

d can extend and adduct shoulder joint

Nerve supply: Radial nerve


Humeromuscular tunnel 肱骨肌管

Composition: Formed by triceps brachii and groove for radial nerve of humerus

Structures passing through the tunnel Radial nerve Deep brachial artery


Radial nerve 桡神经

Origin: From the posterior cord of the br

achial plexus Course: Winds around the back of the a

rm in the spinal groove of the back of the

humerus between the heads of the trice

ps. It pierces the lateral fascial septum a

bove the elbow and divides into superfici

al and deep branches. Distribution: Tricps and skin on back o

f arm


Contents of posterior osseofascial compartment of the forearm

Muscle (10) Blood supply to the muscles: post

erior interosseous artery. Nerve supply to the muscles: radi

al nerve


Posterior group Muscles of forearm

Superficial layer (5) Extensor carpi radialis longus

桡侧腕长伸肌 Extensor carpi radialis brevis

桡侧腕短伸肌 Extensor digitorum 指伸肌 Extensor digiti minimi 小指伸肌 Extensor carpi ulnaris 尺侧腕伸肌


Posterior group Muscles of forearm

Deep layer (5) Supinator 旋后肌 Abductor pollicis longus 拇长展肌 Extensor pollicis brevis 拇短伸肌 Extensor pollicis longus 拇长伸肌 Extensor indicis 示指伸肌

Action: extend radiocapral joint and fi

ngers, and supinate forearm


Supinator 旋后肌

Origin: lateral epicondyle of humerus

and upper part of lateral border of ulna Insertion: upper third of anterior surfa

ce of radius Action: supination of forearm Nerve supply: radial nerve


Nerves and vessels of posterior osseofascial comprtment of the forearm

Deep branch of radial nerve Distribution:

Extensor muscles of forearm brachioradialis skin on back of forearm

Injury: Wristdrop Posterior interosseous artery


Skin incision

Make the skin incision shown in figure and remove the skin and tela superficial fascia. Reflect the skin as far as the midaxillary line.

As you skin the back, notice small nerves and vessels piercing the muscles and coursing upward in to the skin.


The Muscles of Back

Retract the should posterior to relax the trapezius and separate the muscle from underlying structures by passing your hand or scissors beneath the muscle, cut the muscle very close to the spinous processes all the way to inion and cut its attachment to the scapular spin and acromion, leaving the trapezius attached only to the clavicle.

Accessory n.


Back and should region

Define the borders of the deltoid muscle and detach the muscle from the spine and the acromion, leaving the muscle attached of clavicle.

Reflecting the deltoid anteriorly, identify the axiiary n. and posterior circumflex humeral a. on its deep surface. Note that these structures pass through the quadrangular space.


Posterior compartment of the arm

Identify the long head of the triceps brachii and note that it passes between the teres minor and teres major.

Using your fingers, separate the long head from the lateral head of the triceps.

Identify the three heads of the triceps, the long, lateral and medial.

Expose the radial n. and deep brachial a. by carefully cutting the lateral head of the triceps. The nerve and artery lie in the humeromuscular tunnel.


Axillary n.

Posterior humeral circumflex a.

Deep brachial a.

Radial n.

Suprascapular n.& a.

Supraspinatus

Infraspinatus

Teres minor

Teres major

Back and should region


Posterior compartment of the arm

Radial n.Deep brachial a.


Superficial extensors

Identify and clean the extensor carpi radialis longus, and extensor carpi radialis brevis.

More medially, clean the extensor digitorum, extensor digiti minimi, and extensor carpi ulnaris.

Study the arrangement of the tendons as they pass through the extensor retinaculum.

Once you have thoroughly studied their arrangement, cut the retinaculum and reflect the muscle tendons medially to expose the deeper muscles.


Superficial extensors

Extensor carpi radialis brevis 桡侧腕短伸肌Extensor digitorum 指伸肌

Extensor carpi ulnaris 尺侧腕伸肌

Extensor digiti minimi 小指伸肌

Extensor carpi radialis longus 桡侧腕长伸肌


Deep extensors

Identify and clean the abductor pollicis longus, extensor pollicis brevis, and extensor pollicis longus. Then clean the supinator and the extensor indicis (to index finger).

Note that the deep branch of the radial nerve pierces the supinator and then runs along the interosseous membrance supplying innervation to the extensors.


Deep extensors

Supinator

Abductor pollicis longus

Extensor pollicis brevis

Extensor pollicis longus Extensor indicis


Cephalic v.

Radial n.

Basilic v.

Ulnar n.


★You must identify follow structures ！

Muscles Trapezius 斜方肌 Levator scapulae 肩胛提肌 Rhomboideus 菱形肌 Latissimus dorsi 背阔肌 Thoracolumbar fascia 胸腰筋膜 Deltoid 三角肌 Supraspinatus 冈上肌 Infraspinatus 冈下肌 Teres minor 小圆肌 Teres major 大圆肌 Triceps brachii 肱三头肌

Extensor carpi radialis longus 桡侧腕长伸肌

Extensor carpi radialis brevis 桡侧腕短伸肌

Extensor digitorum 指伸肌 Extensor digiti minimi 小指伸肌 Extensor carpi ulnaris 尺侧腕伸肌 Supinator 旋后肌 Abductor pollicis longus 拇长展肌 Extensor pollicis brevis 拇短伸肌 Extensor pollicis longus 拇长伸肌 Extensor indicis 示指伸肌


★You must identify follow structures ！

Vessels Suprascapular a. Posterior humeral circumflex a. Deep brachial a.

Nerves Accessory n. Suprascapular n. Axillary n. Radial n. deep branch of the radial n.

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Dorsal surface of the upper limb