Inquiries regarding reproduction beyond the scope of the above should be sent to the Legal Department, Oxford University Press, at the address above. A sagittal plane can pass through any part of the body, parallel to the median plane.
Terms of position
Where the median plane meets the anterior and posterior surfaces of the body are the anterior and posterior median lines. As you dissect the body, region by region, you will gain first-hand knowledge of the relative positions of structures in the body.
Terms of movement
In other parts of the body, it is loose and elastic, and the skin can move freely. It is thinnest in the eyelids, the nipples and areolas of the breasts, and in some parts of the external genitalia where fat is absent.
Deep fascia
Introduction to tissues of the body
Superficial fascia
Blood flow in the veins is slow and venous return to the heart is aided by: (1) the pressure exerted on the veins by contracting the leg muscles; The positions of the valves in the superficial veins can be seen as localized swellings along their course when the veins are distended with blood.
Lymph vessels
Communications between the superficial and deep veins allow the superficial veins to drain into the deep veins. When possible, you should open the veins in different parts of the body to see the position and structure of the valves.
Blood vessels
Nerves
Dorsal root fibers are outgrowths of cells in the spinal ganglion. They also enter the branches of the dorsal ramus by returning back to the ventral ramus.
Autonomic nervous system
Fibers from the white rami communicantes that terminate in the ganglia of the sympathetic trunk are known as preganglionic nerve fibers. Parasympathetic nerves arise from the second, third and fourth sacral segments of the spinal cord.
Skeletal muscles
More commonly, fibrous tissue forms long, inelastic cords known as tendons or thin, broad sheets called aponeuroses, depending on the arrangement of muscle fibers [Fig. Tendons usually extend over the surface or into the substance of the muscle, thus increasing the surface area for its attachment.
Bursae and synovial sheaths
Based on the shape of the articulating surface, synovial joints are further subclassified [Fig. In a planar synovial joint, the surfaces of the bones are flat, allowing only slight sliding movements (for example: some of the joints between the bones of the hand and foot).
Joints
The articular surfaces of the bones at synovial joints have many different shapes to allow certain movements and prevent others. In the hip, the nearly bulbous head of the femur becomes swollen, tight, and tender.
Bones
In short and irregular bones, ossification begins in the center of the cartilage model and continues outward. Those at the ends of long bones (secondary ossification centers) appear much later, at or after birth.
General instructions for dissection
Dissection instruments
Organization of dissections and commonly used terms
At such crossings, these superficial veins contain valves that prevent backflow of blood from the deep veins.
Deep dissection
Variations
Removal of the skin
The presence of air in the upper part of the peritoneal cavity indicates that this radiograph was taken when the patient was in an upright position. The student must understand the main processes of development and the effects of its abnormalities on the structure and functioning of various systems.
Anatomy of the living body
Special radiological techniques
Unfortunately, ultrasound cannot be used near air or bone, as it does not transmit through them, but it has the advantage that there is no evidence, unlike x-rays, that it has harmful effects on even the most sensitive tissues. It is therefore used as the preferred method to scan the pelvis when there is a chance of pregnancy and to detect gross abnormalities at an early stage.
Magnetic resonance imaging
Computerized tomography
Ultrasound
Introduction
The superior part of the armpit - the crest - lies lateral to the first rib and continues across the superior surface, with the superior opening of the thorax below and the root of the neck above. These vessels and nerves run across the superior surface of the first rib behind the clavicle [Fig. 3.2]).
Bones of the pectoral region and axilla
This continuity allows blood vessels from the chest and nerves from the neck to enter the axilla on their way to the upper limb.
Adjacency of the thorax, neck, and upper limb
Overview of the axilla
The sternoclavicular joint is the only articulation of an upper limb bone with a trunk bone. The scapular muscles either attach the scapula to the humerus or hold it against the thorax.
Surface anatomy of the pectoral region and axilla
Pectoral region
Cutaneous nerves
They supply the part of the skin between the parts supplied by the anterior cutaneous branches (midline anterior to the midclavicular line) and the dorsal ramus (midline of the back approximately 10 cm from the midline). Together, these three nerves supply the skin of the medial side of the arm and the floor of the axilla.
The breast
Skin reflection of the front and side of the chest Objectives
The supraclavicular nerves pass anteriorly to the clavicle to supply the skin of the upper part of the anterior thoracic wall and the shoulder. The clavipectoral fascia lies in the anterior wall of the axilla, deep to the pectoralis major.
The breast Objective
The lower abdominal fibers insert deep into the upper sternocostal fibers, while the intermediate fibers form the base of the U in the anterior axillary fold. The clavicular part passes inferolaterally, fuses with the anterior layer of the U-shaped tendon, and extends further inferiorly on the humerus.
Pectoralis minor
The clavicular part lies perpendicular to the abdominal and lower sternocostal parts and has a different function [fig. The muscle can also return the extended humerus to an anatomical position, then continue to flex the shoulder joint with the clavicular portion passing in front of the shoulder.
Pectoralis major
Pectoral region-1 Objectives
At the insertion, the abdominal part turns under the sternocostal part to form a U-shaped tendon with it. With the arm overhead, the lower fibers work together with the latissimus dorsi to pull the arm down or lift the body, like climbing a rope.
Subclavius
Pectoral region-2 Objectives
Sternoclavicular joint
Sternoclavicular joint Objectives
The convex medial wall is formed by the lateral chest wall (the first five ribs and the intercostal spaces) covered by the serratus anterior. It is continuous medially with the upper thoracic opening and the root of the neck.
Axilla
The top of the axilla is bounded by the clavicle, first rib and upper edge of the scapula. Through the apex vessels of the thorax and the nerves of the brachial plexus enter the axilla from the neck [Fig.
Boundaries and contents
The narrow lateral border is formed by the humerus covered by the upper parts of the biceps and coracobrachialis muscles. These vessels and nerves descend through the armpit to the arm and form the contents of the.
Serratus anterior
Axillary artery
Axilla-1 Objectives
It continues as the subclavian vein at the outer edge of the first rib [Fig.
Axillary lymph nodes
Axillary vein
The ventral rami of the fifth and sixth cervical nerves unite to form the superior trunk [Fig. The posterior cord supplies the extensor muscles and skin on the back of the limb.
Brachial plexus
Axilla-2 Objectives
In the axilla (infraclavicular part) the cords first lie posterior to the first part of the axilla. The musculocutaneous nerve originates in the axilla from the lateral cord of the brachial plexus and.
Surface anatomy of the back
Skin reflection of the back Objectives
Reflect the two skin flaps laterally, remove the skin and superficial fascia from the deep fascia by blunt dissection. This is more difficult than on the flexor surface because of the tighter connections between the superficial fascia and the deep fascia of the back.
Trapezius
Latissimus dorsi
Levator scapulae
Cutaneous nerves and arteries
Muscles that attach the scapula to the trunk
The back Objectives
Expose the upper part of the muscle at the attachments to the clavicle and acromion [Fig. Divide both rhomboid muscles midway between the vertebral spines and the medial edge of the shoulder blade.
Rhomboid minor
The rhomboid minor attaches where the spine of the scapula meets the medial border. Trace the dorsal scapular nerve and the deep branch of the transverse cervical artery deep into them.
Rhomboid major
Identify and trace the dorsal scapular nerve, the deep branch of the transverse scapular artery, and the suprascapular vessels and nerves. Cut the trapezius horizontally halfway between the clavicle and spine of the scapula, and vertically 5 cm lateral to the median plane.
Movements of the scapula
Protraction
Spinal accessory nerve
Dorsal scapular nerve
Transverse cervical artery
Elevation
Depression
Lateral rotation
Medial rotation
Retraction
This enables an easy assessment of the degree of paralysis of a certain movement, after the destruction of a certain nerve.
Muscles acting on, and movements of, the scapula
Answer: The medial border of the scapula would project posteriorly from the thoracic wall.). Unilateral trapezius weakness indicates damage to the spinal accessory nerve on that side.).
Surface anatomy
Regions of the free upper limb will be described and dissected in the following chapters. This chapter provides an overview of the free upper limb, with special attention to the superficial veins, nerves, and lymphatics that are best studied in continuity from the shoulder to the hand.
The arm
On its posterior surface is a triangular subcutaneous area that is distally continuous with the posterior margin (border) of the ulna. The ulna terminates distally in the styloid process which projects from the posteromedial aspect of the cylindrical, slightly expanded head of the bone [Fig.
The forearm
This palpable margin not only allows the entire length of the ulna to be examined for fractures, but also forms the dividing line between the anteromedial flexor group of muscles of the forearm (supplied by the median and ulnar nerves) and the posterolateral extensor group (supplied by the radial nerve) [see Fig. The radial tuberosity lies on the medial aspect of the radius, distal to the neck.
The wrist
Bones at the lateral ends of the proximal and distal rows of carpal bones (scaphoid and trapezius) and at the base of the metacarpal bone of the thumb [fig. The hook of the hamate can be palpated deep through the proximal parts of the muscles that form the ball of the little finger (hypothenar eminence), and the tubercle of the trapezius can be palpated deep through the proximal parts of the muscles that form the ball of the thumb (thenar eminence).
The palm
This is minimal due to the shape of the articular surfaces of the phalanges. The hollow between the proximal parts of the thenar and hypothenar eminence marks the position of the flexor retinaculum.
The digits
Skin reflection of the front of the arm and forearm-1
The other three fingers are not parallel to each other, but come together on flexion to meet the tip of the thumb. See Dissection 5.1 for instructions on skin reflection from the front of the arm and forearm.
Lymph vessels and nodes of the upper limb
Compare your superficial veins with those of the other students, noting their variability and the presence of a cephalic and a basilic vein in most cases.
Superficial veins
Cutaneous nerves of the upper limb
In both upper and lower limbs, the nerves passing to the anterior surface supply a larger area of skin than those passing to the posterior surface. The overlap of these dermatomes is due to the presence of nerve fibers from several ventral rami in each branch of the plexus.
Cutaneous nerves from the spinal nerves adjacent to the brachial plexus
Cutaneous nerves of the front of the arm and forearm-2
It supplies the skin on the back of the forearm at the level of the wrist or occasionally the back of the hand. iv). The area supplied by the nerve varies reciprocally with the other nerves with which it communicates on the back of the hand (ulnar, posterior cutaneous nerve of the forearm and median).
Cutaneous nerves from the lateral cord
It gives off some branches on the lateral side of the arm, descends posteriorly to the lateral epicondyle, and lies in the middle of the back of the forearm. It supplies the lateral two-thirds of the dorsum of the hand, the dorsal surfaces of the thumb and the lateral two and a half fingers by five dorsal digital nerves.
Cutaneous nerves from the medial cord
It descends on the forearm between the extensor and flexor muscle groups, passes back on the distal half of the forearm and pierces the deep fascia 5 cm above the styloid process of the radius.
Cutaneous nerves from the posterior cord
Cutaneous nerves of the upper limb.. called 'proper' when each is distributed to one finger or toe only.
Cutaneous nerves from branches of the medial and lateral cords
Palmar aponeurosis and cutaneous nerves of the palm Objectives
Distally, it is attached to the tubercle of the trapezium and the hook of the ulna and is continuous with the palmar aponeurosis. The extensor retinaculum extends from the lateral side and styloid process of the radius to the ulna.
Deep fascia of the upper limb
The posterior ends of the fibrous flexor sheath are attached to the edges of the palmar surfaces of the phalanges. Known complications: thrombosis formation with occlusion of the injected vein is a common consequence of intravenous injection.
69Surface anatomy
Supraspinatus
Infraspinatus
Muscles attaching the humerus to the scapula
Deltoid
Subscapularis
Teres major
Teres minor
Shoulder region-1 Objectives
Find the inferior border of the infraspinatus and separate it from the teres major and minor. It descends from the infraglenoid tubercle of the scapula and passes between the teres minor and the large muscles close to the humerus.
Shoulder region-2 Objectives
Axillary nerve
Shoulder region-3 Objectives
Circumflex humeral arteries
Suprascapular artery
Suprascapular nerve
Coracoacromial ligament
Coracoclavicular ligament
Articular capsule
Shoulder joint
Shoulder joint Objective
Make a vertical incision through the back of the articular capsule of the shoulder joint. Rotate the arm medially and move the humeral head through the incision in the capsule.
Flexion
The movement of the shoulder joint can take place independently, but it is usually accompanied by movements of the shoulder girdle. Even when the scapula is not moved, the muscles would be tense to maintain a stable scapula upon which the limb can move.
Movements of the limb at the shoulder joint
This action requires two separate movements:. i) lateral rotation of the scapula by the (1) upper and (2) lower fibers of the trapezius, and (3) lower fibers of the serratus anterior;. ii) abduction at the shoulder joint by (5) the deltoid, and (6) the supraspinatus. When adduction is produced against resistance, two separate movements are involved: (i) medial rotation of the scapula by (1) levator scapulae, (2) rhomboid minor, and (3) rhomboid major;. ii) adduction of the humerus by (5) teres major, (4) latissimus dorsi and pectoralis major (not shown).
Extension
Abduction
Adduction
Medial and lateral rotation of the humerus
This allows an easy assessment of the degree of paralysis of a given movement after the destruction of a given nerve. Axillary nerve injury and resultant paralysis of the deltoid and teres minor affect severely.
Muscles, movements, and nerves of the shoulder joint
The dorsal scapular artery and the suprascapular artery are branches of the thyrocervical trunk of the subclavian artery. The posterior humeral circumflex artery and the circumflex scapular arteries are branches of the axillary artery.
Anterior compartment
The deep fascia that surrounds the hand sends barriers between muscle groups to allow them to slide one after the other and increase the area for exit. Two of these septa – the lateral and medial intermuscular septa – run to the corresponding supracondylar lines and epicondyles of the humerus, thus dividing the distal part of the arm into anterior and posterior parts [Fig.
Biceps brachii and coracobrachialis
Front of the arm Objectives
Identify the lower lateral cutaneous nerve of the arm and the posterior cutaneous nerve of the forearm arising from the radial nerve. Locate the main neurovascular bundle of the arm immediately deep to the deep fascia, medial to the biceps.
Brachialis
Action of muscles of the front of the arm
It passes inferolaterally to the groove for the radial nerve on the posterior surface of the humerus. The bundle then contains the median nerve and the brachial artery and veins in the lower third of the arm.
Musculocutaneous nerve (C. 5, 6)
Gentle traction on that nerve will confirm its continuity with the nerve already exposed on the lateral side.
Principal neurovascular bundle of the arm
In the middle of the arm, it pierces the medial intermuscular septum and passes distally into the posterior compartment of the arm. It enters the forearm by passing over the posterior surface of the medial epicondyle [Fig.
Brachial artery
It enters the forearm by passing over the posterior surface of the medial epicondyle [Fig. artery leaves the fossa at the apex; leaves the ulnar artery by passing deep to the pronator teres. The tendon of the biceps passes between the bones of the forearm to reach the radial tuberosity.
Posterior compartment
The median nerve supplies its medial muscles and leaves the fossa through the pronator teres. If the elbow is flexed and the ends separated, the contents of the fossa are seen after the deep fascia covering it has been removed.
Triceps brachii
Radial nerve
Cubital fossa
Back of the arm Objectives
The medial head of the triceps originates in the humerus, inferior to the groove [Fig. The superficial branch is a sensory nerve to the back of the fingers and hand [see Fig.
Bones and surface anatomy of the forearm and hand
Muscles of the forearm
Front of the forearm and hand
Palmar aponeurosis
Front of the forearm Objectives
The flexor carpi ulnaris is immediately medial to the palmaris longus in the proximal third of the forearm. Note its attachment to the flexor retinaculum and its continuity with the apex of the palmar aponeurosis.
Superficial palmar arch
Palm of the hand-1 Objectives
Remove any remnants of the palmaris brevis, and follow the ulnar nerve and artery distally, superficial to the flexor retinaculum. Deep to the arch are the branches of the median and ulnaris nerves, and further deeper are the long flexor tendons [Fig.
Fibrous flexor sheaths
In eo sunt tendines flexoris carpi radialis, flexoris pollicis longus, flexor digitorum longus, flexor digitorum superficialis et nervus medianus [Fig.
Synovial sheaths of flexor tendons
Flexor retinaculum
The flexor pollicis longus, the median nerve, and the tendons of the two flexors (superficial and deep) of the digits are seen in the carpal tunnel. B) MR image of the hand at the same level. A window has been created in the fibrous flexor sheath to show the long flexor tendons.
Arteries of the flexor compartment of the forearm
Front of the forearm and palm of the hand Objectives
In the forearm, cut transversely through the humerulnar head of the flexor digitorum superficialis. Separate the median nerve from the deep surface of the flexor digitorum superficialis and trace it.
Nerves of the flexor compartment of the forearm and hand
Works together with the flexor carpi ulnaris and produces pure flexion of the wrist. 8.7], and gives a branch to it and to the medial half of the flexor digitorum profundus.
Muscles of the front of the forearm and hand
The flexor carpi radialis runs obliquely across the anterior surface of the forearm to the anterolateral surface of the wrist. Function: It flexes all joints of the thumb (including the carpometacarpal joint) and the wrist.
Fascial compartments of the palm
Palm of the hand-2 Objectives
Avoid damage to the branch of the median nerve and the deep branch of the ulnar nerve that supply these muscles. The deep branch of the ulnar nerve passes to the first dorsal interosseous muscle now exposed in the palm.
Movements of the thumb
The abductor pollicis brevis crosses the anterior surfaces of the same two joints but produces abduction primarily at the carpometacarpal joint. The sesamoid bones of the thumb are small, egg-shaped bones that lie within the tendons and attach to the capsule of the metacarpophalangeal joint.
Short muscles of the thumb
The muscles converge on the posteromedial surface of the base of the proximal phalanx of the thumb as a common tendon containing a small sesamoid bone. In a firm grip, sesamoid bones prevent compression of the tendons against the bone and facilitate their movements on the bone.
Deep palmar arch
In summary, the deep branch of the ulnar nerve supplies all the muscles of the palm, except the three muscles of the thenar eminence and the lateral two lumbricals. The flexor pollicis brevis frequently receives a branch from the ulnar nerve in addition to that from the median nerve, and occasionally the ulnar nerve is its only source of supply.
Extensor compartment of the forearm and hand
Short muscles of the little finger
Deep branch of the ulnar nerve
Back of the forearm Objectives
It is attached to the posterior border of the ulna by the thick deep fascia. Divide the fascia over the extensor carpi ulnaris in the proximal third of the forearm to demonstrate the anconeus [Fig.
Muscles of the back of the forearm
More medially, the extensor indicis lies medial to the tendons of the extensor digitorum [Fig. The anconeus is supplied by a branch of the radial nerve to the medial head of the triceps.).
Deep branch of the radial and posterior interosseous nerves
Arteries of the back of the forearm and hand
Extensor retinaculum and synovial sheaths of extensor tendons
Back of the hand-1 Objective
The poorly formed remnant of the artery descends between the deep and superficial muscles of the dorsal carpal rete [Fig. It descends on the membrane of the dorsal carpal rete with the terminal branch of the posterior interosseous nerve.
Back of the hand-2 Objectives
Just proximal to the metacarpophalangeal joint, the extensor digitorum tendon joins the extensor extensor. These thickened lateral edges pass obliquely back to the posterior surface of the proximal interphalangeal joint.
Extensor tendons of the fingers
The base of the triangle extends anteriorly on each side of the metacarpal head to join the deep transverse metacarpal ligament. As they do so, they send tendon bundles into the midline extensor longus tendon.
Extensor expansion
Part of the tendon passes deep into the extensor expansion at the base of the proximal phalanx. Nerve supply: all interossei are supplied by the deep branch of the ulnar nerve [Fig.
Movements of the fingers
The dorsal interossei go to the lateral sides of the index and middle fingers and to the medial sides of the middle and ring fingers. Actions: palmar interossei adducts the fingers and thumb to the line of the middle finger, lengthens the interphalangeal joints and plays a role in flexing the metacarpophalangeal joints.
Deep transverse metacarpal ligament and palmar ligaments
Actions: dorsal interossei abduct the fingers from the line of the middle finger, extend the interphalangeal joints, and play a role in flexion of the metacarpophalangeal joints (especially the first dorsal interosseous). The palmar interossei passes to the medial sides of the thumb and index finger and to the lateral sides of the ring and little fingers.
Muscles inserted into the extensor expansion
Abduction and adduction of the fingers (but not the thumb) occurs at the metacarpophalangeal interossei. These rotational movements are only possible in abduction, due to the shape of the saddle joint.
Extensors of the thumb
Thumb impingement is usually (but not necessarily) associated with flexion at the metacarpophalangeal and interphalangeal joints of the thumb. Flexor pollicis longus is primarily used when the tip of the thumb is opposite the tip of the finger or when power is required.
Elbow joint
Elbow joint Objective
Movements at the elbow joint
Synovial membrane
Interior of the elbow joint Objective
The anterior and posterior parts of the fibrous capsule contain fibers that travel obliquely downward and medially. The nerve supply is through the anterior and posterior interosseous nerves and the dorsal branch of the ulnar nerve.
Wrist joint
The synovial membrane, which covers the fibrous capsule and covers the carpal interosseous ligaments, may be continuous with that of the distal radio-ulnar joint through a defect in the triangular disc.
Fibrous capsule of the wrist joint
Wrist joint-1 Objective
Movements at the wrist joint
Wrist joint-2 Objective
Extensor digitorum Humerus, lateral epicondyle Extensor extensions of fingers Extension, prevented by radial and ulnar flexors of carpus. This is because flexion is prevented by radial and ulnar extensors of the wrist; and extension is prevented by radial and ulnar flexors of the wrist.
Distal radio-ulnar joint
Articular disc
Fibrous capsule of the distal radio-ulnar joint
Synovial membrane of the distal radio-ulnar joint
Radio-ulnar joints
Proximal radio-ulnar joint
Annular ligament of the radius
Interosseous membrane Objective
In pronation, the radius rotates about an axis that passes through the center of the head of the radius and the head of the ulna. The head of the radius rotates in the annular ligament, while the distal end rotates around the stationary ulna, carrying the hand and articular disc with it.
Interosseous membrane of the forearm
However, pronation and supination can be performed around the axis of one of the fingers. The pronator teres has the maximum mechanical advantage, as it inserts at the point of maximum lateral convexity of the radius.
Movements at the radio-ulnar joints
Superior and inferior radio-ulnar joints
As described above, the ulna remains stationary, and the little finger rotates on its own axis. Pronation is produced by muscles on the anterior surface of the forearm that run from medial to lateral—pronator teres, pronator quadratus, and flexor carpi radialis.
Intercarpal, carpometacarpal, and intermetacarpal joints
The main joint complex
The pizoform is held in position against the pull of the flexor carpi ulnaris by the pisohamate and pisometacarpal ligaments. The joint allows the pisiform to maintain proper alignment during adduction and abduction of the arm.
Medial four carpometacarpal joints
Carpometacarpal joint of the thumb
Articular surfaces and movements
Intercarpal joints
Pisiform joint
In full flexion, the plate rests on the palmar surface of the metacarpal body. In the medial four digits, the margins of the palmar plate provide attachment to:.
Intermetacarpal joints
When the joint is aligned, it moves to the palmar surface of the head and, in full extension, to its distal surface. It is essential in holding or grasping objects and allows the thumb to functionally represent half of the hand.
Nerve supply
Metacarpophalangeal joints
Fibrous capsules of
Interphalangeal joints
Sesamoid bones
Movements at metacarpophalangeal joints
The third and fourth lumbricals are paralyzed, resulting in clawing of the fourth and fifth fingers. The claw-like appearance of the hand is reduced (and not aggravated, as one would expect from a higher-level injury).
Motor distribution
A neurological examination of the upper extremity is part of the general neurological examination and is used to assess the integrity of the motor and sensory nerves supplying the upper extremity. Clinical Applications 10.1 and 10.2 at the end of this chapter will explore the practical application of this knowledge.
Median nerve
Ulnar nerve
Musculocutaneous nerve
Subscapular nerve
Thoracodorsal nerve
Impact on the wrist joint Weakened flexion of the wrist Flexor carpi ulnaris and part of the profundus flexor digitorum are paralyzed. Weak flexion is caused by the flexor digitorum superficialis Impact on the PIP joints of all.
Long thoracic nerve
- The supraclavicular nerves supply the skin down to a horizontal line at the level of
- The anterior axillary wall consists of the following muscles, EXCEPT
- The intercostobrachial nerve communicates with the
- The inferior angle of the scapula corresponds approximately to the level of the
- Retraction of the scapula is caused by the following muscles, EXCEPT
- The nerve supply of the latissimus dorsi is by the
- The bones that can be felt in the anatomical snuffbox are all, EXCEPT
- The upper lateral cutaneous nerve of the arm arises from the
- The following arteries are involved in the anastomosis around the scapula, EXCEPT
- The axis of movement of supination and pronation passes through the centre of the head of the radius proximally and the
- The structures that pass in the carpal tunnel are all, EXCEPT
- The anterior interosseous nerve is a branch of the
- Carpal tunnel syndrome is caused due to compression of the
- The muscle producing adduction of the wrist is
- The action of lumbricals is
Posteriorly, they articulate with the sides of the sacrum in two sacro-iliac joints. The proximal end of the fibula (the head) does not participate in the knee joint.
Surface anatomy and bones
Skin reflection Objective
Front of the thigh
Superficial veins Objectives
To expose the upper part of the long vein saphena and the tributaries in this area. Locate the long saphenous vein in the superficial fascia of the medial part of the anterior surface of the thigh.
Saphenous opening
The long and short saphenous veins form channels parallel to the deep veins (plantar and tibial veins) of the lower limbs. Blood in the deep veins is pushed against gravity by the pumping action produced by the contraction of the surrounding muscles.
Superficial inguinal lymph nodes
The pressure in the superficial veins increases, and they will eventually dilate and lead to further valve incompetence and worsening of the situation (see Clinical Application 18.1). Directly from the lumbar plexus: ilio-inguinal nerve, femoral branch of the genitofemoral nerve, lateral cutaneous nerve of the thigh.
Long saphenous vein
Superficial and cutaneous nerves
Strip the superficial fascia from the anterior and lateral aspect of the thigh with open dissection. From the deep surface of the fascia lata, three intermuscular septa pass into the linea aspera of the femur.
Fascia lata
Deep fascia of the thigh Objective
Fascia lata is attached to the length of the ligament, exerts traction on it and makes the inguinal ligament convex inferiorly. Lateral to the pubic tubercle, the deep surface of the inguinal ligament extends posteriorly to the pecten pubis and forms the lacunar ligament.
Femoral sheath
The inguinal ligament extends from the anterior superior iliac spine laterally to the pubic tubercle medially. The free base of the lacunar ligament lies medial to the opening, through which the femoral vessels included in the.
Patellar bursae
The free edge of the aponeurosis is curved back on itself to form a groove on the abdominal aspect.
Inguinal ligament
Here, muscles (psoas and iliacus) and nerves (femoral and lateral cutaneous nerve of the thigh) from the posterior abdominal wall enter the thigh behind the iliac fascia and the lateral portion of the inguinal ligament [Fig. Also deep in the medial part of the inguinal ligament, the external iliac vessels in the abdomen become the femoral vessels in the thigh.
Femoral triangle
Inferiorly, the canal lies behind the opening of the saphenous vein and cribriform fascia, and in front of the fascia covering the pectineus muscle.
Femoral canal
Femoral sheath, canal, and ring Objective
The deep external pudendal artery arises from the femoral artery near the base of the triangle. Three or four deep inguinal lymph nodes lie along the medial side of the femoral vein.
Femoral triangle Objective
It originates from the posterolateral side of the femoral artery, turns down behind it and goes posterior to the adductor longus. The lateral circumflex femoral artery runs laterally between the branches of the femoral nerve and runs posterior to the sartorius.
Adductor canal
When the knee is flexed, the muscle slides backward into the medial border of the popliteal fossa. Actions: it flexes the hip joint and the knee joint and rotates the thigh laterally to bring the limb into the position assumed when sitting cross-legged (sartorius comes from the Latin word sartor, meaning tailor. This name was chosen as a reference to the cross-legged position in which the tailors once sat).
Sartorius
Front of the thigh Objective
Femoral artery
The superficial veins of the groin terminate in the long saphenous vein, and the medial and lateral circumflex veins enter the femoral vein, although the corresponding arteries are usually branches of the profunda artery.
Femoral nerve
Femoral vein
It supplies a large part of the quadriceps and sends a long branch through the vastus lateralis to anastomose at the knee joint.
Tensor fasciae latae
Iliotibial tract
Lateral circumflex femoral artery
Intermuscular septa
Quadriceps femoris
Lateral intermuscular septum Objective
It has a long linear origin from the root of the greater trochanter to the lateral supracondylar line [Fig. The muscle fibers run downward and forward to the patella and the anterolateral part of the fibrous capsule of the knee joint.
Adductor longus
Medial side of the thigh
Medial compartment of the thigh-1 Objectives
Adductor brevis
Pectineus
Accessory obturator nerve
Medial circumflex femoral artery
Medial compartment of the thigh-2
An important action of the adductor muscles is to stabilize the hip bone on the femur. Distal to the adductor longus, it enters the adductor canal and forms a plexus with branches from the medial anterior cutaneous nerve of the thigh and the saphenous nerve.
Obturator externus
They are active in the supporting limb during the entire period in which it supports the body weight during walking (see also action of gluteal muscles: Gluteus maximus, p. 189; Actions of the gluteus medius and mini-mus, p. 196). It descends medially to the psoas muscle, to the lateral wall of the lower pelvis where it lies lateral to the ovary.
Obturator artery
The anterior branch descends into the thigh, anterior to the obturator externus and adductor brevis.
Gracilis
Adductor magnus
Actions of the adductor muscles
It also produces medial rotation of the thigh because its insertion is lateral to the axis of rotation of the femur. When the femoral neck is fractured, the iliopsoas causes marked lateral rotation of the distal femoral segment (and the distal limb).
Psoas major and iliacus
Skin reflection and cutaneous nerves-1
They are difficult to find because of the density of the superficial fascia, but it is usually possible to identify the branches of the median nerves [Fig.
Gluteus maximus
Structures deep to the gluteus maximus
Gluteus maximus Objective
