Bones of the upper limbs and their connections. Skeleton of the human upper extremities: meaning and main functions Structure of the upper extremities of the human anatomy in detail
The bones of the upper limb are represented by the upper limb girdle (scapula and clavicle) and the free upper limb (humerus, ulna, radius, tarsals, metatarsals and phalanges, Fig. 42).
Upper limb belt (shoulder girdle) is formed on each side by two bones - the collarbone and the scapula, which are attached to the skeleton of the body with the help of muscles and the sternoclavicular joint.
Collarbone is the only bone that connects the upper limb to the skeleton of the body. The collarbone is located in the upper part of the chest and can be easily felt along its entire length. Above the clavicle are the major and minor supraclavicular fossa, and below, closer to its outer end - subclavian fossa. The functional significance of the clavicle is great: it sets the shoulder joint at the proper distance from the chest, providing greater freedom of movement of the limb.
Rice. 42. Skeleton of the upper limb.
Rice. 43. Clavicle: (A - top view, B - bottom view):
1-acromial end, 2-body, 3-sternal end.
Collarbone- a paired S-shaped bone, it has a body and two ends - medial and lateral (Fig. 43). The thickened medial or sternal end has a saddle-shaped articular surface for articulation with the sternum. The lateral or acromial end has a flat articular surface - the place of articulation with the acromion of the scapula. On the lower surface of the clavicle there is a tubercle (a trace of ligament attachment). The body of the clavicle is curved in such a way that its medial part, closest to the sternum, convexes anteriorly, and the lateral part posteriorly.
Spatula(Fig. 44) is a flat triangular bone, slightly curved backwards. The anterior (concave) surface of the scapula is adjacent at the level of the II–VII ribs to the posterior surface of the chest, forming subscapular fossa. The muscle of the same name is located in the subscapular fossa. The vertical medial edge of the scapula faces the spine.
Rice. 44. Shoulder blade (posterior surface).
The lateral angle of the scapula, with which the upper epiphysis of the humerus articulates, ends in a shallow glenoid cavity, having an oval shape. Along the anterior surface, the glenoid cavity is separated from the subscapularis fossa neck of the scapula. Above the upper edge of the depression is supraglenoid tubercle(attachment site of the tendon of the long head of the biceps brachii muscle). At the lower edge of the glenoid cavity there is subarticular tubercle, from which the long head of the triceps brachii muscle originates. Above the neck, a curved coracoid process, protruding above the shoulder joint in front.
A relatively high ridge runs along the posterior surface of the scapula, called spine of the scapula. Above the shoulder joint the spine forms a wide process - acromion, which protects the joint from above and behind. It contains an articular surface for articulation with the collarbone. The most prominent point on the acromion (acromial point) is used to measure shoulder width. The depressions on the posterior surface of the scapula, located above and below the spine, are called respectively supraspinatus And infraspinatus fossae and contain muscles of the same name.
Skeleton of the free upper limb formed by the bones of the shoulder, forearm and hand. In the shoulder area there is the humerus, on the forearm there are two bones - the radius and the ulna, the hand is divided into the wrist, metacarpus and fingers (Fig. 42).
Brachial bone(Fig. 45) refers to long tubular bones. It consists of diaphysis And two epiphyses– proximal and distal. In children, between the diaphysis and epiphyses there is a layer of cartilaginous tissue - metaphysis, which is replaced by bone tissue with age. Upper end ( proximal epiphysis) has a spherical articular head, which articulates with the glenoid cavity of the scapula. The head is separated from the rest of the bone by a narrow groove called anatomical neck. Behind the anatomical neck are two tubercles(apophyses) – large and small. The greater tubercle lies laterally, the lesser tubercle lies slightly anterior to it. Bone ridges extend from the tubercles downwards (for muscle attachment). Between the tubercles and ridges there is a groove in which the tendon of the long head of the biceps brachii muscle is located. Below the tubercles at the border with the diaphysis is located surgical neck(the site of the most common shoulder fractures).
Rice. 45. Humerus.
In the middle of the bone body on its lateral surface there is deltoid tuberosity, to which the deltoid muscle is attached, a groove of the radial nerve runs along the posterior surface. The lower end of the humerus is widened and slightly bent anteriorly ( distal epiphysis) ends on the sides with rough protrusions - medial And lateral epicondyles, serving for attachment of muscles and ligaments. Between the epicondyles there is an articular surface for articulation with the bones of the forearm - condyle. It has two parts: medially lies block, having the form of a transversely located roller with a notch in the middle; it serves for articulation with the ulna and is covered by its notch; above the block are located in front coronoid fossa, behind - olecranon fossa. Lateral to the block there is an articular surface in the form of a ball segment - head of the condyle of the humerus, serving for articulation with the radius.
Bones of the forearm are long tubular bones. There are two of them: the ulna, lying medially, and the radius, located on the lateral side.
Elbow bone (Fig. 46) – long tubular bone. Her proximal epiphysis thickened, it has trochlear notch, serving for articulation with the block of the humerus. The cutting ends ahead coronoid process, behind - elbow. This is also where radial notch, forming a joint with the articular circumference of the head of the radius. On the bottom distal epiphysis there is an articular circle for articulation with the ulnar notch of the radius and a medially located styloid process.
Radius (Fig. 46) has a more thickened distal end than the proximal one. At the upper end it has head, which articulates with the head of the condyle of the humerus and with the radial notch of the ulna. The head of the radius is separated from the body neck, below which the radial one is visible on the anteroulnar side tuberosity– insertion site of the biceps brachii muscle. At the lower end are located articular surface for articulation with the scaphoid, lunate and triquetrum bones of the wrist and ulnar notch for articulation with the ulna. The lateral edge of the distal epiphysis continues into styloid process.
Hand bones(Fig. 47) are divided into the bones of the wrist, metacarpus and the bones that make up the fingers - the phalanges.
Rice. 47. Hand (back surface).
Wrist is a collection of eight short spongy bones arranged in two rows, each of four ossicles. Proximal or first row of wrist, closest to the forearm, is formed, counting from the thumb, by the following bones: scaphoid, lunate, triquetrum and pisiform. The first three bones, connecting, form an elliptical articular surface convex towards the forearm for articulation with the radius. The pisiform bone is sesamoid and does not participate in articulation. Distal or second row of wrist consists of bones: trapezium, trapezoid, capitate and hamate. On the surfaces of each bone there are articular platforms for articulation with neighboring bones. On the palmar surface of some carpal bones there are tubercles for the attachment of muscles and ligaments. The bones of the wrist together represent a kind of arch, convex on the back and concave on the palm. In humans, the bones of the wrist are firmly strengthened by ligaments, which reduce their mobility and increase their strength.
Pastern is formed by five metacarpal bones, which belong to the short tubular bones and are named in order from 1 to 5, starting from the side of the thumb. Each metacarpal bone has base, body And head. The bases of the metacarpal bones articulate with the bones of the wrist. The heads of the metacarpal bones have articular surfaces and articulate with the proximal phalanges of the fingers.
Finger bones - small, short tubular bones lying one after another, called phalanges. Each finger consists of three phalanges: proximal, middle and distal. The exception is the thumb, which has a proximal and distal phalange. Each phalanx has a middle part - a body and two ends - proximal and distal. At the proximal end is the base of the phalanx, and at the distal end is the head of the phalanx. At each end of the phalanx there are articular surfaces for articulation with adjacent bones.
Connections of the bones of the upper limb girdle (Table 2). The belt of the upper limb is connected to the skeleton of the body through sternoclavicular joint; at the same time, the collarbone seems to move the upper limb away from the chest, thereby increasing the freedom of its movements.
Sternoclavicular joint(Fig. 48) formed sternal end of the clavicle And clavicular notch of the sternum. Located in the joint cavity articular disc. The joint is strengthened ligaments: sternoclavicular, costoclavicular and interclavicular. The joint is saddle-shaped in shape, however, due to the presence of a disc, movement in it they occur around three axes: around the vertical - movement of the clavicle forward and backward, around the sagittal - raising and lowering the clavicle, around the frontal - rotation of the clavicle, but only with flexion and extension in the shoulder joint. The scapula moves along with the collarbone.
AC joint(Fig. 49) flat in shape with little freedom of movement. This joint is formed by the articular surfaces of the acromion of the scapula and the acromial end of the clavicle. The joint is strengthened by powerful coracoclavicular and acromioclavicular ligaments.
Rice. 48. Sternoclavicular joint (front view, on the left
side, the joint is opened with a frontal incision):
1-clavicle (right), 2-anterior sternoclavicular ligament, 3-interclavicular ligament, 4-sternal end of the clavicle, 5-intraarticular disc, 6-first rib, 7-costoclavicular ligament, 8-sternocostal joint ( 11th rib), 9-intra-articular sternocostal ligament, 10-cartilage of the 11th rib, 11-synchondrosis of the manubrium of the sternum, 12-radiate sternocostal ligament.
Rice. 49. Acromioclavicular joint:
1-acromial end of the clavicle; 2-acromio-clavicular ligament;
3-coracoclavicular ligament; 4-acromion of the scapula;
5-coracoid process; 6-coracoacromial ligament.
table 2
Main joints of the upper limb
| Joint name | Articulating Bones | Joint shape, axis of rotation | Function |
| Sternoclavicular joint | Sternal end of the clavicle and clavicular notch of the sternum | Saddle-shaped (there is an intra-articular disc). | Axes: vertical, sagittal, frontal |
| Movements of the clavicle and the entire girdle of the upper limb: up and down, forward and backward, circular movement | Shoulder joint | Head of the humerus and glenoid cavity of the scapula | Globular. Axes: vertical, transverse, sagittal |
| Movements of the shoulder and the entire free upper limb: flexion and extension, abduction and adduction, supination and pronation, circular movement | Elbow joint (complex): 1) humerus, 2) humerohumeral, 3) proximal radioulnar | Condyle of the humerus, trochlear and radial notches of the ulna, head of the radius | Block-shaped. |
| Axes: transverse, vertical | Flexion and extension, pronation and supination of the forearm | Wrist joint (complex) | Carpal articular surface of the radius and first row of carpal bones |
Ellipsoidal.
Axes: transverse, sagittal. Flexion and extension, adduction and abduction, pronation and supination (simultaneously with the bones of the forearm)
The movements of the scapula occur up and down, forward and backward. The scapula can rotate around the sagittal axis, while the lower angle moves outward, as happens when the arm is raised above the horizontal level.
1-joint capsule, 2-articular cavity of the scapula, 3-head of the humerus, 4-articular cavity, 5-tendon of the long head of the biceps brachii muscle, 6-articular labrum, 7-inferior inversion of the synovial membrane of the joint.
Shoulder joint(Fig. 50) connects the humerus, and through it the entire free upper limb with the girdle of the upper limb, in particular with the scapula. The joint is formed humeral head And glenoid cavity of the scapula. Along the circumference of the cavity there is cartilaginous labrum, which increases the volume of the cavity without reducing mobility, and also softens shocks and shocks when the head moves. The joint capsule is thin and large in size. It is strengthened by the coracohumeral ligament, which comes from the coracoid process of the scapula and is woven into the joint capsule. In addition, the fibers of the muscles passing near the shoulder joint (supraspinatus, infraspinatus, subscapularis) are woven into the capsule. These muscles not only strengthen the shoulder joint, but also, when moving in it, pull back its capsule, protecting it from pinching.
Due to the spherical shape of the articular surfaces, it is possible in the shoulder joint movements around three mutually perpendicular axes: around the sagittal (abduction and adduction), transverse (flexion and extension) and vertical (pronation and supination). Circular movements (circumduction) are also possible. Flexion and abduction of the arm is possible only to the level of the shoulders, since further movement is inhibited by the tension of the articular capsule and the support of the upper end of the humerus into the acromion. Further raising of the arm is carried out due to movements in the sternoclavicular joint.
Elbow joint(Fig. 51) is a complex joint formed by the connection in the common capsule of the humerus with the ulna and radius. There are three joints in the elbow joint: the humeroulnar, humeroradial and proximal radioulnar.
Block-shaped humeroulnar joint form the trochlea of the humerus and the trochlear notch of the ulna (Fig. 52). Globular humeroradial joint consists of the head of the condyle of the humerus and the head of the radius. Proximal radioulnar joint connects the articular circumference of the head of the radius with the radial notch of the ulna. All three joints are enclosed in a common capsule and have a common articular cavity, and therefore are combined into one complex elbow joint.
The joint is strengthened by the following ligaments (Fig. 53):
- ulnar collateral ligament, running from the medial epicondyle of the humerus to the edge of the trochlear notch of the ulna;
- radial collateral ligament, which starts from the lateral epicondyle and attaches to the radius;
- annular ligament of the radius, which covers the neck of the radius and is attached to the ulna, thus fixing this connection.
Rice. 52. Humeral-ulnar joint (vertical section):
4-trochlear notch of the ulna, 5-coronoid process of the ulna.
Rice. 53. Ligaments of the elbow joint:
1-articular capsule, 2-ulnar collateral ligament, 3-radial collateral ligament, 4-radial ligament.
In the complex elbow trochlear joint, flexion and extension, pronation and supination of the forearm are carried out. The humeral-ulnar joint allows flexion and extension of the arm at the elbow. Pronation and supination occur due to the rotational movement of the radius around the ulna, carried out simultaneously in the proximal and distal radioulnar joints. In this case, the radius bone rotates along with the palm.
The bones of the forearm are interconnected by combined joints - proximal and distal radioulnar joints, which function simultaneously (combined joints). Throughout the rest of their length, they are connected by an interosseous membrane (Fig. 19). The proximal radioulnar joint is included in the capsule of the elbow joint. Distal radioulnar joint rotational, cylindrical. It is formed by the ulnar notch of the radius and the articular circumference of the head of the ulna.
Wrist joint(Fig. 54) is formed by the radius and the bones of the proximal row of the wrist: scaphoid, lunate and triquetrum, connected by interosseous ligaments. The ulna does not reach the surface of the joint; between it and the bones of the wrist there is an articular disc.
In terms of the number of bones involved, the joint is complex, and in terms of the shape of the articular surfaces, it is ellipsoidal with two axes of rotation. The joint allows flexion and extension, abduction and adduction of the hand. Pronation and supination of the hand occur together with the same movements of the bones of the forearm. Movements in the wrist joint are closely related to movements in midcarpal joint, which is located between the proximal and distal rows of the carpal bones, excluding the pisiform bone.
Rice. 54. Joints and ligaments of the hand (dorsal surface):
4-articular disc, 5-wrist joint, 6-middle carpal joint,
7-intercarpal joints, 8-carpometacarpal joints, 9-intercarpal joints, 10-metacarpal bones.
Connections of the bones of the hand. There are six types of joints in the hand: midcarpal, intercarpal, carpometacarpal, intermetacarpal, metacarpophalangeal and interphalangeal joints (Fig. 54).
Midcarpal joint, having an S-shaped joint space, is formed by the bones of the distal and proximal (except for the pisiform bone) rows of the wrist. The joint is functionally combined with the wrist joint and allows for a slightly expanded degree of freedom of the latter. Movements in the midcarpal joint occur around the same axes as in the radiocarpal joint (flexion and extension, abduction and adduction). However, these movements are inhibited by ligaments - collateral, dorsal and palmar.
Intercarpal joints connect the lateral surfaces of the carpal bones of the distal row and strengthen the connection with the radiate ligament of the wrist.
Carpometacarpal joints connect the bases of the metacarpal bones with the bones of the distal row of the wrist. With the exception of the articulation of the trapezius bone with the metacarpal bone of the thumb (I), all carpometacarpal joints are flat, their degree of mobility is small. The connection of the trapezoid and first metacarpal bones provides significant mobility of the thumb. The capsule of the carpometacarpal joint is strengthened by the palmar and dorsal carpometacarpal ligaments, so the range of movement in them is very small.
Intermetacarpal joints flat, with low mobility. They are composed of the lateral articular surfaces of the bases of the metacarpal bones (II-V), strengthened by the palmar and dorsal metacarpal ligaments.
Metacarpophalangeal joints ellipsoid, connecting the bases of the proximal phalanges and the heads of the corresponding metacarpal bones, strengthened by collateral (lateral) ligaments. These joints allow movements around two axes - in the sagittal plane (abduction and adduction of the finger) and around the frontal axis (flexion-extension).
Thumb joint has a saddle-shaped shape, abduction and adduction to the index finger, opposition of the finger and reverse movement, and circular movements are possible in it.
Interphalangeal joints block-shaped, connect the heads of the upper phalanges with the bases of the lower ones, flexion and extension are possible in them.
Chapter 1. Topic: Skeleton of the upper limb.
Summary.
Classification of bones forming the girdle of the upper limb and the free part of the upper limb. The structure of the bones of the shoulder girdle (clavicle, scapula). The structure of the bones of the free part of the upper limb (humerus, bones of the forearm and hand). Basic morphological formations. Anatomical basis for the most common injuries.
Purpose and objectives of the lesson
Students should know:
1. The main morphological formations of the bones of the girdle and free upper limb.
2. Latin and Russian names.
3. Locations of common fractures on the ulna and radius (olecranon, distal ends).
Students should be able to:
1. Identify any individual bone of the upper limb skeleton.
2. Distinguish the bones of the right upper limb from the left.
3. Find parts of the bone - body (diaphysis), ends (epiphysis), processes, etc.
4. Characterize the bone by shape - tubular (long or short, flat, spongy, mixed).
5. Feel the protruding bone points on yourself.
6. Freely navigate diagrams and drawings from a textbook and atlas.
All bones should be studied on the skeleton, as well as using a set of individual bones, a textbook and atlas on human anatomy and museum preparations (display case No. 2).
In the human upper limb skeleton, the upper limb girdle and the free part of the upper limb are distinguished.
1. Upper limb belt (cingulum membri superioris) consists of two bones - the clavicle and the scapula.
Spatula (scapula)- a flat, triangular-shaped bone. Adjacent to the posterior surface of the chest from the 2nd to 7th ribs.
In the shoulder blade there are:
edges medial (margo medialis), lateral (margo lateralis), superior (margo superior),
angles superior (angulus superior), inferior (angulus inferior) and
lateral ( angulus lateralis)
surfaces costal (facies costalis), posterior (facies posterior )
On the back surface there is an awn ( spina scapule), which ends with the humeral process ( acromion) and supraspinatus (fossa supraspinata) and infraspinatus (fossa infraspinata) fossa.
Rice. 1-1. structure of the bones of the upper shoulder girdle (front view).
The coracoid process (processus coracoideus) extends from the upper edge
The lateral angle forms the articular cavity (cavitas glenoidalis) and the supraarticular (tuberculum cupraglenoidale) and subarticular (tuberculum infraglenoidale) tubercles.
Collarbone(clavicula ) S-shaped curved tubular bone. It is the only bone connecting the upper limb to the skeleton of the body, providing greater freedom of movement of the limb.
The clavicle is divided into: a body (corpus claviculae) and two ends: sternal (extremitas sternalis), acromial (extremitas acromialis)
The upper surface of the clavicle is smooth, and the lower surface is rough. Near the acromial end there are: a cone-shaped tubercle (tuberculum conoideum) and a trapezoidal line (linea trapezoidea ) . Ligaments are attached to these tubercles.
Rice. 1-2. The structure of the bones of the upper shoulder girdle (rear view).
2. Free part of the upper limb(pars libera membri superioris ) .
It is formed by: the humerus, bones of the forearm and hand.
Brachial bone(humerus ) refers to typical long tubular bones. There is a body of the humerus (corpus humeri) and two ends - upper (proximal) and lower (distal).
The body of the humerus has the shape of a cylinder at the top and becomes triangular at the bottom.
At this level, the posterior surface (facies posterior) and two lateral surfaces are distinguished: the medial anterior (facies anterior medialis) and the lateral anterior (facies anterior lateralis) ).
Rice. 1-3. The structure of the bones of the forearm.
In the middle lateral part of the body of the bone there is a deltoid tuberosity (tuberositas deltoidea), which is the site of attachment of the muscle of the same name. Below the deltoid tuberosity, on the posterior surface of the bone there is a spiral groove of the radial nerve (sulcus nervi radialis).
The upper end forms the head of the humerus (caput humeri). A groove runs along its edge - the anatomical neck (collum anatomicum).
Behind the neck there are two tubercles (for muscle attachment). The greater tubercle (tuberculum majus) lies laterally. The small tubercle (tuberculum minus) is located anterior to the large one.
From each tubercle there are ridges for muscle attachment. Between the tubercles passes the intertubercular groove (sulcus intertubercularis), in which the tendon of the long head of the biceps brachii muscle is located.
The narrowest part of the bone, located between the head and the body, is called the surgical neck (collum chirurgicum), the site of the most common fractures.
The lower end is expanded and ends with the condyle of the humerus (condylus humeri). It distinguishes between a block (trochlea humeri) and a head (capitulum humeri) for articulation with the radius and ulna.
In front above the trochlear is the coronoid fossa (fossa coronoidea ) . Above the head of the condyle is the radial fossa (fossa radialis ) .
Posteriorly – fossa olecranon i).
On the sides of the condyle there are epicondyles: medial (epicondylus medialis) and lateral (epicondylus lateralis) for attachment of muscles and ligaments. On the posterior surface of the medial epicondyle is the groove of the ulnar nerve (sulcus nervi ulnaris).
Forearm(antebrachium ) consists of two bones: medially located ulna(ulna) and laterally radius(radius).
They belong to the long tubular bones.
Each bone consists of a body and two ends. The bodies of both bones are triangular in shape with three surfaces and edges.
One surface faces backward (facies posterior), the other faces forward (facies anterior), the third faces laterally at the radius (facies lateralis), and medially at the ulna (facies medialis).
Of the three edges, one is sharp and faces the adjacent bone, limiting the interosseous space. This is the interosseous edge ( margo interosseus). In addition to general characteristics, each bone has characteristic structural features. At the proximal end of the ulna there is a trochlear notch (incisura trochlearis), ulnar (olecranon), and coronoid (processus coronoideus) processes. At the distal end is the head of the ulna (caput ulnae), the styloid process (processus styloideus) on the medial side.
At the proximal end of the radius there is a head (caput radii) with articular surfaces: a fossa (fovea articularis) and a circle (circumferentia articularis). At the distal end there is the carpal articular surface (facies articularis carpalis) and the styloid process (processus styloideu s) from the lateral side.
Some bone formations are an important landmark for the doctor, so you need to be able to palpate the scapula - the spine, acromion, lower and medial angles.
On the collarbone there is the body and ends. On the humerus are the head and epicondyles. Styloid process on the radius and ulna. Olecranon process and head on the ulna.
Brush (manus) consists of carpal bones (ossa carpi), metacarpal bones (ossa metacarpi) and finger bones, phalanges (ossa digitorum, phalanges ) .
Rice. 1-4. The structure of the bones of the hand (front view).
. 
Rice. 1-4. The structure of the bones of the hand (back view).
Wrist (carpus) consists of eight spongy bones arranged in two rows.
Proximal row (from the thumb): scaphoid ( os scaphoideum) lunate (os lunatum), triangular (os triquetrum), pisiform (os pisiforme), which is a sesamoid bone, i.e. located deep within the flexor carpi ulnaris tendon.
Distal row: trapezium bone (os trapezium), trapezoid (os trapezoideum), capitate (os capitatum), hamate (os hamatum).
A carpal groove is formed on the palmar surface, which is limited laterally by the tubercle of the scaphoid and trapezium bones, medially by the hook of the hamate and the pisiform bone.
Metacarpal bones (ossa metacarpi (I-V), belong to the short tubular bones. Each consists of a base, body and head.
Bones of the fingers or phalanges (ossa digitorum, ph alanges ), They are short tubular bones.
Each finger, except the first (thumb), has three phalanges: proximal, middle and distal. The thumb has only two phalanges - proximal and distal.
Thumb, 1st (pollex, digitus primus).
Index finger, 2nd (index, digitus secundus).
Middle finger, 3rd (digitus medius, tertius).
Ring finger, 4th (digitus anularis, quartus).
Little finger, 5th (digitus minimus, quintus)
Questions for self-control.
- On what part of the humerus are the deltoid tuberosities located?
- Where does the groove of the radial nerve pass?
- What is the condyle of the humerus formed by?
- What processes does the trochlear notch of the ulna end with?
- List the names of the fingers in Latin.
Test tasks.
(Answer in writing in your workbook).
Choose one correct answer.
- Which of the following bones has a styloid process?
a) shoulder
b) ulna
c) collarbone
d) shoulder blade
d) sternum
- Which of the following bones belongs to the girdle of the upper limb?
a) shoulder blade
b) shoulder
c) radial
d) ulna
- Which of the following bones is spongy in structure?
a) shoulder blade
b) collarbone
c) capitate bone
d) humerus
d) radius
- The proximal row of carpal bones includes the following bones except
a) semilunar
b) triangular
c) pisiform
d) scaphoid
d) trapezoidal
- The distal row of carpal bones includes the following bones except
a) trapezoid
b) trapezoidal
c) capitate
d) hook-shaped
d) pisiform
- The carpal groove is bounded by the following bones except
a) hook of the hamate bone
b) tubercle of the scaphoid
c) tubercle of the trapezium bone
d) pisiform
e) capitate
- The first metacarpal bone has an articular surface at the proximal end for articulation with
a) triangular
b) capitate
c) trapezoidal
d) bone - trapezium
d) scaphoid
- On which formation of the humerus is the groove of the ulnar nerve located?
a) on the medial epicondyle
b) on the lateral epicondyle
c) on the trochlea of the humerus
d) on the head of the condyle of the humerus
e) on the greater tubercle of the humerus
Equipment.
Skeleton. Individual bones of the upper limb skeleton. Museum natural anatomical preparations (display case No. 2).
Literature.
- Human anatomy. //Ed. M.R. Sapina - M.: Medicine, T.1, 1993, pp. 123-126, 126-133.
- Human anatomy. //Ed. M.G. Gain. – M.: Medicine, 1999
- Sinelnikov R.D., Sinelnikov Y.R. Atlas of human anatomy.-M.:Medgiz, T.1, 1989. p.82-84, p.84-100.
Goals and objectives of the lesson.
Students should know:
1. Types of continuous connections of the skull bones (syndesmoses, synchondroses, synostoses).
2. The structure of the temporomandibular joint, features of movement.
3. Features of movement in the temporomandibular joint
Students should be able to:
1. Orientate yourself in natural anatomical preparations, show the main morphological formations.
2. Be able to distinguish between different types of joints of the skull bones.
The bones of the skull are connected to each other using continuous joints and a discontinuous joint (temporomandibular joint).
Rice. 2-1. Skull (cranium) rear view.
Continuous connections of the skull bones are represented by:
1. Fibrous joints in the form of sutures,
2. Cartilaginous joints - synchondroses (at the base of the skull), which turn into synostoses with age.
The seams are jagged, scaly and flat.
1. The bones of the roof of the skull are connected to each other using serrated and scaly sutures.
The medial edges of the parietal bones are connected by a serrated suture called sagittal (sutura sagittalis).
The frontal bone is connected to the parietal bones using a serrated suture called coronal suture (sutura coronalis).
The parietal and occipital bones are connected by a serrated suture called lambdoid suture (sutura lambdoidea).
The scales of the temporal bone are connected to the parietal bone and the greater wing of the sphenoid bone using a scaly suture.
The bones of the facial skull are connected using flat sutures. The names of the individual sutures on the skull are derived from the names of the connecting bones, for example sutura temporozygomatica.
Rice. 2-2. Skull side view.
2. Synchondroses - connections of bones with the help of cartilage (fibrous). There are sphenooccipital synchondrosis and petrooccipital synchondrosis. In place of sphenoid-occipital synchondrosis, synostosis forms with age.
Temporomandibular joint (art. temporomandibularis) The joint is a paired, complex ellipse.
Rice. 2-3. Temporomandibular joint articulatio temporo-mandibularis internal view.
Rice. 2-4. Temporomandibular joint articulatio temporo-mandibularis external view.
Attachment of the joint capsule. On the temporal bone it is attached anterior to the articular tubercle, posteriorly at the level of the petrotympanic fissure. On the condylar process, the capsule is attached anteriorly along the edge of the head, posteriorly 0.5 cm below the posterior edge of the head of the mandible. The articular cavity is divided by cartilage into two isolated stages: upper and lower. Accordingly, the upper synovial membrane and the lower synovial membrane are distinguished.
Joint ligaments. From the lateral side - lateral ligament (lig. laterale). It starts from the base of the zygomatic process of the temporal bone and is attached to the posterolateral surface of the neck of the condylar process.
The sphenomandibular (lig. sphenomandibuiare) is located on the medial side of the joint. It starts from the spine of the sphenoid bone and is attached to the uvula of the lower jaw.
Stylomandibular ligament (lig. stylomandibulare). It starts from the styloid process and attaches to the inner surface of the angle of the lower jaw.
Since movements in the joints (right and left) occur together, they are functionally combined into a combined joint.
Functions:
1. Raising and lowering the lower jaw; that is, movement along the frontal axis.
2. movement of the lower jaw to the right and left
3. forward displacement of the lower jaw
When lowering the lower jaw, three phases are distinguished:
1. slight lowering of the lower jaw. Movement occurs in the lower floor of the joint, the disc remains in the glenoid fossa
2. significant lowering of the lower jaw. The cartilaginous disc, together with the head of the lower jaw, slides forward and extends onto the articular tubercle.
3. maximum lowering of the lower jaw. Movement occurs only in the lower floor around the frontal axis. The articular disc is located on the articular tubercle.
When the lower jaw moves forward, movements occur only in the upper floor of the joint. When the lower jaw moves to the right, the head with the disc in the upper floor slides in the left joint. At this time, in the right temporomandibular joint, the head rotates around a vertical axis. When the lower jaw shifts to the left, the head slides in the right joint, and vertical rotation occurs in the left.
Questions for self-control
1. Name the fibrous connections between the bones of the skull
2. List the synchondroses at the base of the skull
3. Phases in the movement of the temporomandibular joint
4. Name the ligaments of the temporomandibular joint
Test tasks
Exercise: choose one correct answer.
1. The parietal bones are connected by
A) coronal suture.
B) sagittal suture.
B) synchondrosis.
D) synostosis.
D) lambdoid suture.
2. The frontal bones are connected to the parietal bones using
A) sagittal suture.
B) lambdoid suture.
B) coronal suture.
D) frontoparietal suture.
D) synchondrosis.
3. The occipital bone is connected to the parietal bones using:
A) occipito-parietal suture.
B) parieto-occipital suture.
B) lambdoid suture.
D) coronal suture.
D) sagittal suture.
4. The ligaments of the temporomandibular joint include
A) lateral ligament.
B) medial ligament.
B) collateral ligament.
D) ligamentum flavum.
D) longitudinal ligament.
5. The ligaments of the temporomandibular joint include:
A) medial ligament.
B) collateral ligament.
B) sphenoparietal ligament.
D) sphenomandibular ligament.
D) sphenoid-maxillary ligament.
Choose one wrong answer:
6. The joints of the skull bones include all of the following, except:
A) sagittal suture.
B) coronal suture.
B) temporomandibular joint.
D) stony-occipital synchondrosis.
D) atlanto-occipital junction.
7. All of the following formations belong to the temporomandibular joint, except:
A) articular disc.
B) lateral ligament.
B) collateral ligament.
D) heads of the lower jaw.
D) mandibular fossa.
8. For the temporomandibular joint, all statements are true except:
A) complex joint.
B) combined joint.
B) elliptical joint.
D) biaxial joint.
D) triaxial joint.
9. For the temporomandibular joint, all statements are true except:
A) combined joint.
B) uniaxial joint.
B) biaxial joint.
D) movements take place in the frontal and vertical axis.
D) movements take place in the frontal and sagittal axes.
10. The joints of the skull bones include all of the following, except:
A) lambdoid suture.
B) coronal suture.
B) injecting.
D) synchondrosis.
D) synostosis.
Equipment
Museum stand No. 14, wet preparation “temporomandibular joint”, skull.
Literature
1. “Human Anatomy” volume 1 edited by M.R. Sapina. Publishing house "Medicine" 1996 pp.162-165.
2. “Atlas of Human Anatomy” volume 1, edited by R.D. Sinelnikova. Publishing house "Medicine" 1989 Page 149-151, p. 35.
3. “Atlas of Human Anatomy”, edited by F. Netter. Publishing house GEOTAR-Med 2003 Fig. 2-3.11.
Goals and objectives of the lesson
Students should know:
1. The structure of the sterno-clavicular joint, acromioclavicular joint and shoulder joint.
2. Features of movement in the listed joints.
Students should know:
1. The main formations of these joints, as well as periarticular formations.
2. Features of movement in the sternoclavicular joint, acromioclavicular joint.
3. Features of movement in the shoulder joint, features of fixation of the shoulder joint and the clinical significance of this fixation.
Joints of the upper limb girdle (articulationes cinguli membri superioris):
1. Sternoclavicular joint
2. Acromioclavicular joint
Sternoclavicular joint (articulatio sternoclavicularis). The joint is formed by the sternal articular surface of the clavicle and the clavicular notch of the manubrium of the sternum. The joint is complex because Inside the joint there is an articular disc that divides the articular surface into two chambers. The shape is close to saddle or flat. It is a multi-axis joint.
Ligaments that strengthen the joint:
1. Anterior sternoclavicular ligament (lig. sternoclaviculare anterius).
2. Posterior sternoclavicular ligament (lig. sternoclaviculare posterius), which is a thickening of the fibrous membrane of the joint capsule in front and behind.
3. Interclavicular ligament (lig. Intraclaviculare), located above the jugular notch of the sternum.
4. The costoclavicular ligament (lig costoclaviculare) is located at some distance from the joint.
Rice. 3-1. Sternoclavicular joints, artt. sternoclaviculares; front view. (1.- discus articularis; 2.- capsula artcularis; 3.- lig. interclaviculare; 4.- lig. sternoclaviculare anterius; 5.- lig. costoclaviculare; 6.- clavicula; 7.- costa 1; 8.- manubrium sterni.
Acromioclavicular joint (articulatio acromioclavicularis). Formed by the acromion of the scapula and the acromial end of the clavicle. Inside the joint there is cartilage (discus articularis). The joint is flat, inactive, multi-axial.
Rice. 3-2. Acromioclavicular joint art. acromio-clavicularis; right. (1.- lig. coracoacromiale; 2.- lig. trapezoideum; 3.- lig. conoideum; 4.- extremitas acromialis claviculae; 5.- processus coracoideus; 6.- lig. transversum scapulae superius; 7.- scapula; 8 .- labrum glenoidale; 9.- cavitas glenoidalis; 10.- acromion;
Ligaments that strengthen the joint:
1. Acromioclavicular ligament (lig. acromioclaviculare) – thickening of the joint capsule.
2. Coracoclavicular ligament (lig. coracoclaviculare) - located away from the joint and consists of two bundles:
a) trapezoid ligament (lig. trapezoideum) – located laterally
b) conical ligament (lig.conoideum) – located medially.
Own ligaments of the scapula:
1. The coracoacromial ligament (lig. coracoacromiale) stretches in the form of an arch above the shoulder joint from the anterior edge of the acromial process to the processus coracoideus.
2. The superior transverse ligament of the scapula (lig. transversum scapulae superius) is stretched over the scapular notch and turns it into an opening.
3. The lower transverse ligament of the scapula (lig. transversum scapulae inferius) runs from the base of the acromion through the neck of the scapula to the posterior edge of the glenoid cavity; a passes underneath it. suprascapularis.
Questions for self-control
1. Features of the structure of the shoulder joint
2. Structure of the sternoclavicular joint
3. Structure of the acromioclavicular joint
Test tasks
Choose one incorrect answer.
1. All formations belong to the sternoclavicular joint, except:
A) articular surface of the sternal end of the clavicle.
B) clavicular notch of the manubrium of the sternum.
B) radiate ligament.
D) interclavicular ligament.
D) sternoclavicular ligaments.
2. All of the following structures belong to the shoulder joint, except:
A) head of the humerus
B) glenoid cavity of the scapula
B) labrum
D) coracobrachial ligament
D) acromioclavicular ligament
3. The acromioclavicular joint is strengthened by all of the following ligaments, except:
A) acromioclavicular ligament
B) coracoclavicular ligament
B) trapezoid ligament
D) conical ligament
D) deltoid ligament
4. The proper ligaments of the scapula include all except:
A) superior transverse ligament
B) medial transverse ligament
B) inferior transverse ligament
D) coracoacromial ligament
5. All statements are true for the shoulder joint except:
A) ball and socket joint
B) multi-axis joint
B) the articular surfaces of the scapula and shoulder are complemented by the articular lip
D) has a coracohumeral ligament
D) has an acromiohumeral ligament
Equipment
Museum showcase No. 14, wet preparations “sternoclavicular joint”, “acromioclavicular joint”, “shoulder joint”
Literature
4. “Human Anatomy” volume 1, edited by M.R. Sapina. Publishing house "Medicine" 1996 Pages 180-186
5. “Atlas of Human Anatomy” volume 1, edited by R.D. Sinelnikova. Publishing house "Medicine" 1989 Page 151-154
6. “Atlas of Human Anatomy”, edited by F. Netter. Publishing house GEOTAR-Med 2003 Fig. 394.
Purpose and objectives of the lesson.
Study the muscles of the head, their origin, insertion and function. Study the fascia of the head.
The muscles of the head and face are divided into facial and chewing muscles.
Facial muscles:
They develop from the mesenchyme of the second visceral arch.
They have no fascia.
Have at least one point of attachment to the skin.
Innervated by the facial nerve.
Reflect the emotional state of a person.
Among the facial muscles are the facial muscles of the head and face.
Facial muscles of the head (cranial vault).
1. M. occipitofrontalis, occipitofrontal muscle,
beginning: linea nuchae superior;
attachment: eyebrow skin;
has two abdomens: occipital (venter occipitalis) and frontal (venter frontalis), connected by a tendon aponeurosis (helmet - galea aponeurotica)
function: when contracted, horizontal folds appear on the skin of the forehead, the upper eyelid and eyebrow rise. The face acquires an expression of attention and mental tension.
2.M. temporoparietalis, temporoparietal muscle,
origin: inner surface of ear cartilage;
attachment: fan-shaped to the lateral surface of galea aponeurotica.
Function: gives the face an expression of interest: “ears on top of the head.”
3. M. Procerus, muscle of the proud
Beginning: bony dorsum of the nose;
Attachment: skin of the glabella;
Function: when it contracts, a skin fold appears that runs transversely to the root of the nose
Rice. 4-2. Head muscles
Mimic muscles of the face.
According to their location and function, the facial muscles are divided into:
muscles surrounding the palpebral fissure;
muscles surrounding the oral cavity;
muscles surrounding the nostrils and
muscles of the auricle.
The circular muscles act as sphincters, and the radial muscles act as dilators.
Facial muscles of the orbital region.
1. M. orbicularis oculi, orbicularis oculi muscle:
It surrounds the palpebral fissure, being located in the peripheral part of the pars orbitalis, on the bony edge of the orbit, and in the inner part, pars palpebralis, on the eyelids. The smaller pars lacrimalis arises from the wall of the lacrimal sac, and by expanding it, affects the outflow of tears. Pars palpebralis closes the eyelids, and pars orbitalis closes the eye.
2.M. corrugator supercilii, corrugator muscle:
Beginning: medial part of the brow ridge;
Attachment: eyebrow skin;
Function: pulls the skin of the forehead down and medially, forming vertical folds above the root of the nose.
Nasal muscles.
1. M. nasalis, nasal muscle
Consists of two parts: pars transversa, and pars alaris. Pars transversa, narrowing the openings of the nostrils, directs air to the olfactory region of the nasal cavity (“sniffing”). It starts from the maxillae in the fossa canina area, goes perpendicular to the back of the nose, connects with the muscle of the other side. Pars alaris starts from the maxillae below and medially and is woven into the skin of the wing of the nose, dilating the nostrils, providing deep breathing.
2. M. depressor septi nasi, muscle that depresses the nasal septum:
Origin: above the medial incisor maxillae;
Attachment: cartilaginous part of the nasal septum;
Function: pulls down the nasal septum.
Muscles of the auricle area
1. M. auricularis anterior, anterior auricular muscle
Origin: temporal fascia and tendon helmet anterior to the ear;
Attachment: ear skin;
Function: pulls the auricle forward.
2. M. auricularis superior, superior auricular muscle:
Beginning: tendon helmet up from the ear
Attachment: upper part of the auricle cartilage;
Function: pulls the auricle upward.
3. M. auricularis posterior, inferior auricular muscle
Beginning: processus mastoideus
Attachment: posterior surface of the auricle;
Function: pulls the ear back.
Facial muscles of the mouth
1. M. orbicularis oris, the orbicularis oris muscle forms the muscular basis of the upper and lower lips; consists of two parts pars marginalis (marginal) and pars labialis (labial). Pars labialis lies in the thickness of the lips, attaches to the corners of the mouth, where it is woven into the skin and mucous membranes. Pars marginalis is located in the corners of the mouth, where other muscles surrounding the oral cavity are woven into it;
Function: closes the oral cavity, participates in sucking, chewing, articulation.
2. M. depressor anguli oris, depressor anguli oris muscle:
Origin: lower edge of mandibulae;
Attachment: corner of mouth;
Function: pulls the corner of the mouth down, giving the face an expression of sorrow.
3. M. depressor labii inferioris, muscle that depresses the lower lip:
Beginning: outer surface of the body of the lower jaw;
Attachment: skin of lower lip;
Function: pulls the lower lip down and to the side
4. M. mentalis, mental muscle
Beginning: jugum alveolare of the medial incisor;
Attachment: skin of the chin;
Function: lifts the skin of the chin, protruding the lower lip.
5. M. Buccinator, buccal muscle:
Origin: crista buccinatoria mandibulae, posterior edge of the alveolar process maxillae and on a special vertical tendon cord, raphe buccopharyngea, located between maxillae and mandibulae.
Attachment: woven into the orbicularis oris muscle;
Function: forms the muscular basis of the cheek, pulls the corner of the mouth back, presses the cheek to the teeth. "The trumpeter muscle."
6. M. levator labii superioris, levator labii superioris muscle
Origin: infraorbital margin of the maxilla;
Attachment: upper lip;
Function: raises the upper lip, forms a nasolabial furrow..
7. M. zygomaticus minor, zygomatic minor muscle
Origin: zygomatic bone
Attachment: nasolabial fold;
Function: raises the corner of the mouth.
8. M. zygomaticus major, zygomaticus major muscle:
Origin: zygomatic bone;
Attachment: corner of mouth;
Function: pulls the corner of the mouth upward and outward, a typical muscle of laughter.
9. M. levator anguli oris, levator anguli oris muscle:
Beginning: in the depths of fossa canina;
Attachment: skin of the corner of the mouth;
Function: raises the corner of the mouth.
10. M. risorius, laughter muscle:
Origin: masticatory fascia;
Attachment: skin of the corner of the mouth;
Function: smile muscle, forms a dimple on the cheek.
M. Platysma (superficial neck muscle) should also be classified as facial muscles due to its origin, function, structural features, and innervation.
Origin: superficial plate of the pectoral fascia below the clavicle;
Attachment: edge of the lower jaw and corner of the mouth;
Function: lifts the skin of the neck, pulls the corner of the mouth downwards.
Chewing muscles.
Develop from the mesenchyme of the first visceral arch (mandibular)
They originate on the bones of the skull and attach to the lower jaw.
Innervated by the trigeminal nerve.
1. M. masseter, masticatory muscle
beginning: lower edge of the zygomatic bone and zygomatic arch;
attachment: outer side of the mandibular ramus;
2. M. temporalis, temporal muscle
beginning: temporal fossa of the skull to linea temporalis;
attachment: processus coronoideus mandibulae;
function: presses the lower teeth against the upper teeth, horizontal fascicles push the lower jaw back.
3. M. pterygoideus medialis, medial pterygoid muscle
beginning: fossa pterygoidea of the pterygoid process of the sphenoid bone;
attachment: tuberositas pterygoidea mandibulae;
function: presses the lower teeth against the upper teeth.
4. M. pterygoideus lateralis, lateral pterygoid muscle
beginning: the lower surface of the greater wing and the pterygoid process of the sphenoid bone;
attachment: collum mandibulae, bursa and articular disc of the temporomandibular joint;
function: with unilateral contraction, it moves the lower jaw to the side, with bilateral contraction, it pushes the lower jaw forward; pulls the articular capsule and articular disc forward.
Fascia of the head
There is no fascia in the facial area, since the facial muscles lie directly under the skin. An exception is M. Buccinator, which is covered at the back with dense fascia buccopharyngea, which loosens anteriorly, merging with the tissue of the cheek, and posteriorly fuses with raphe buccopharyngea and continues into the connective tissue of the pharynx.
Fascia temporalis covers the muscle of the same name, starts at the top from the linea temporalis, and at the bottom is attached to the zygomatic arch with two plates to the outer and inner sides of the arch.
Fascia massaterica covers the masticatory muscle, is attached above to the zygomatic arch, and below to the edge of the lower jaw. Posteriorly goes into fascia parotidea, covering the parotid salivary gland.
Questions for self-control.
1. In which direction does the lower jaw move when the right lateral pterygoid muscle contracts?
2. Which of the masticatory muscles lowers the lower jaw?
3. list the features of M. Platysma that are common to other facial muscles.
Test tasks.
1. draw 5 schematic facial expressions (like emoticons) and describe the tension of which facial muscles gives the face such an expression.
2. present a description of the masticatory muscles (name, origin, attachment, function, fascia) in the form of a table.
3. In the form of a table, present the movements of the lower jaw and the muscles that carry them out.
1. Human Anatomy, ed. M.R. Sapina, Moscow, Medicine, 1993, T.1., P.283-295.
2. Human anatomy. // Under. ed. M.G. Gain.-M.: Medicine, 1999, p.
3. Sinelnikov R.D., Sinelnikov Ya.R. Atlas of human anatomy. - M.: Medgiz, T.1, 1990. P.
Muscles acting on the joints of the shoulder girdle and free upper limb.
- M. Pectoralis major, pectoralis major muscle:
Origin: from the clavicle (pars clavicularis), sternum and cartilage of the II-VII ribs (pars sternocostalis), sheath of the rectus abdominis muscle (pars abdominalis);
Attachment: crista tuberculi majoris humeri;
Function: brings the arm to the body and turns it inward; with fixed arms, it acts as an inspiratory muscle.
 | Rice. 5-1. M. Pectoralis major |
- M. Pectoralis minor pectoralis minor muscle
Beginning: II-V ribs;
Insertion: coracoid process of scapula;
Function: tilts the scapula forward and down, with a strengthened scapula, raises the ribs.
- M. subclavius, subclavius muscle
Origin: cartilage of the 1st rib;
Insertion: acromial end of clavicle;
Function: strengthens the sternoclavicular joint.
- M. serratus anterior, the serratus anterior muscle is adjacent to the side of the chest and forms the medial wall of the axillary cavity.
Origin: teeth from the upper nine ribs;
Insertion: medial edge of scapula
Function: pulls the scapula laterally and upward, turning it upward with the glenoid cavity, which allows you to raise the arm above the horizontal.
 | Rice. 5-2. 4. M. Serratus anterior, |
Autochthonous (own) chest muscles
- Mm. intercostales externi, the external intercostal muscles perform intercostal spaces in the back from the tubercle of the rib to the cartilage of the rib in front, where they continue in membrane intercostalis externa. They consist of flat short muscle bundles mixed with tendon bundles. Their fibers go from top to bottom and forward.
Origin: the lower edges of the ribs from the tubercles of the ribs to the beginning of the cartilaginous part;
Insertion: upper edge of the underlying rib.
Function: raise the ribs.
- Mm. intercostales interni, the internal intercostal muscles also perform intercostal spaces from the sternum in front to the angle of the rib behind, where they continue in membrane intercostalis interna. They lie inward from the external muscles so that the groove on the lower edges of the ribs is between the external and internal intercostal muscles. Fiber mm. intercostals interni are directed from top to bottom and posteriorly, i.e. perpendicular to the fibers of the external intercostal muscles.
Origin: upper edge of the rib;
Attachment: lower edge of the overlying rib.
Function: lowers the ribs.
Development and age-related features of the limb skeleton
The skeleton of the upper limb is divided into two parts:
1) skeleton of the upper limb girdle;
2) skeleton of the free upper limb.
The skeleton of the upper limb girdle includes the shoulder blades and collarbones.
The scapula is a flat, triangular-shaped bone located on the back surface of the body. The lateral edge of the scapula is thickened and has a glenoid cavity that serves to connect with the head of the humerus.
The clavicle is an S-shaped bone curved along its long axis. It is located horizontally in front and above the chest at the border of the neck and is easily palpable along its entire length. The clavicle has two ends - sternal and acromial. The first is thickened, has an articular surface with the sternum. The second one is also thickened and connects to the acromion (acromion is the lateral part of the scapula protruding outward). The function of the clavicle is that it helps strengthen the position of the scapula, keeping the shoulder joint some distance from the chest. The upper limb girdle connects the free upper limb to the torso, serves as a site of muscle attachment and increases the range of motion of the upper limbs.
The skeleton of the free upper limb consists of three sections.
1) The humerus is a typical long tubular bone. At the proximal (upper) end of the humerus there is a head, which faces the scapula and has an articular surface.
The head of the bone is separated from the rest by an anatomical neck, along the edge of which the shoulder joint bursa is attached. The most narrowed part of the humerus below the anatomical neck is called the surgical neck, as fractures often occur here. The distal (lower) part of the humerus forms the condyle, the articular surface of which serves to connect with the bones of the forearm.
2) The skeleton of the forearm is formed by the ulna and radius bones.
The ulna is tubular and triangular in shape. Its proximal end is thickened and has a trochlear notch for connection with the humerus. The distal end represents the head of the ulna. On the lateral side, the head forms an articular surface for articulation with the radius, and on the bottom - with triangular cartilage.
The radius is a long tubular bone. Unlike the ulna, the radius has a thicker distal end. The proximal end has a head, on the upper surface of which there is a fossa for connection with the head of the condyle of the humerus. And along the edge there is an articular surface for connection with the ulna.
3) The skeleton of the hand is divided into three sections:
a) wrist - eight small bones of irregular shape, arranged in two rows. They belong to the short spongy bones;
b) the metacarpus consists of five short tubular bones. The metacarpal bone of the first finger is shorter than the others, but more massive. Each metacarpal bone has a base, a body and a head;
c) phalanges of the fingers are short tubular bones. Each finger consists of three phalanges: proximal, middle and distal.
The exception is the first finger, which has only two phalanges: proximal and distal. The articular surfaces of the distal and middle phalanges, as well as the articular surface of the head of the proximal phalanx, have a block-like shape. The articular surface of the base of the proximal phalanges is connected to the head of the metacarpal bone by the spherical bone joint.
In addition to these bones, the hand also has sesamoid bones.
They are located in the thickness of the muscle tendons (most often going to the thumb and index fingers from the palmar surface of the hand) and increase the leverage of those muscles that are attached to them.
The functions of the upper and lower extremities in humans are different. The upper limbs are organs of labor; they are very mobile, capable of performing a wide variety of very precise movements. The lower limbs are used for support and movement. Their bones and joints are more massive, their mobility, compared to the upper limbs, is limited.
The skeleton of the limbs, both upper and lower, is a system of levers with a similar structure. The limbs consist of a belt and a free part. The bones of the belt are connected to the skeleton of the body. The free part of the limbs (upper and lower) consists of three segments: the proximal (upper) is represented by one bone, the middle by two bones, the distal (lower) consists of many bones.
Bones of the upper limbs and their connections
The skeleton of the upper limbs consists from the girdle of the upper limbs (shoulder girdle) and free upper limbs. The upper limb girdle has two bones on each side - the collarbone and the scapula.
Only the collarbone is connected to the skeleton of the body by a joint. The shoulder blade is inserted between the collarbone and the free part of the upper limb.
Bones of the upper limb girdle. The girdle of the upper limbs includes paired shoulder blades and a collarbone connected by joints.
Collarbone -- a paired, curved tubular bone with a body and two ends - the sternum and the acromion.
The collarbone is easily palpable in a living person. The functional role of the clavicle is very important - it moves the shoulder joint away from the chest, providing freedom of movement of the arm.
Spatula is a flat, triangular-shaped bone adjacent to the posterior surface of the chest at the level of the 2nd to 5th rib. The dorsal surface is divided by a transversely oriented protrusion - the spine of the scapula - into two fossae: supraspinatus and infraspinatus. Laterally, the spine of the scapula continues into the acromion, which has an articular surface for articulation with the clavicle. The scapula has three angles - inferior, lateral and superior. The upper edge of the scapula passes laterally and anteriorly into the coracoid process. The thickened lateral angle of the scapula has a glenoid cavity that forms an articulation with the head of the humerus.
The skeleton of the free part of the upper limb consists of the humerus, the bones of the forearm (ulna, radius) and the hand (bones of the wrist, metacarpus and phalanges of the fingers).
Brachial bone - a long tubular bone, has a body and two ends - the upper and lower epiphyses. The upper epiphysis is thickened and forms a spherical head that articulates with the glenoid cavity of the scapula. Just below the head there are two tubercles (large and small), to which the muscles are attached. The tubercles are separated by a longitudinal groove in which the long tendon of the biceps brachii muscle lies. The bone in the area where the upper epiphysis meets the body of the bone is thin. When injured in this area, the bone often breaks, which is why it is called the surgical neck of the humerus. The lower epiphysis is expanded and ends with a condyle for articulation with the ulna and radius bones at the elbow joint. On the sides of the condyle are the lateral and medial epicondyles, which can be easily felt in the area of the elbow joint.
Bones of the forearm classified as long tubular bones. There are two of them - elbow bone lies medially (closer to the midline of the body); radius located next to the ulna, on the lateral side of the forearm. The upper ends of the ulna and radius bones participate in the formation of the elbow joint, and the lower ends participate in the formation of the wrist joint along with the upper row of carpal bones. The upper (proximal) epiphysis of the ulna is thickened, has two processes - ulnar (back) and radial (front), separated by a trochlear notch. On the lateral side of the upper and lower epiphyses there are articular platforms for articulation with the adjacent radius.
At the radius, on the medial side of the upper and lower epiphyses, there are corresponding articular fossae for articulation with the ulna. The thickened lower end of the radius bears an articular surface that forms a joint with the upper (proximal) row of carpal bones.
Hand bones include the carpal bones, metacarpal bones and bones (phalanxes) of the fingers.
Skeleton of the wrist consists of 8 spongy bones (short), arranged in two rows, 4 bones in each row, and having articular surfaces for articulation with neighboring bones. Pastern has five short tubular metacarpal bones, which have a base, a body and a head. The bases of the metacarpal bones are equipped with articular surfaces for articulation with the bones of the second row of the wrist, and their heads with the bases of the first phalanges of the fingers. Finger bones- these are short tubular bones (phalanxes), located one behind the other. Four fingers have three phalanges - proximal, middle and distal (ungual). The exception is the thumb, which has two phalanges (proximal and distal).
Skeleton of the lower limbs
The skeleton of the lower extremities consists of the girdle of the lower extremities (paired pelvic bone) and the free part of the lower extremities (bones of the thigh, lower leg and foot). The bones of the girdle of the free part of the lower limb are more massive and thick than those of the upper limb, since they are adapted to bear the weight of the entire body both in a calm state and under dynamic loads: walking, running, jumping.
The girdle of the lower extremities (pelvic girdle) is formed by a pair of massive, flattened pelvic bones; between these bones the sacrum is located at the back.
Hip bone up to 12-14 years old, it consists of three separate bones connected by cartilage: the ilium, the pubis and the ischium. The fused bodies of these bones form depression (vertugular), which is the articular surface for articulation with the head.
Ilium located above the acetabulum, ischium - below and behind her, pubic bone - anteriorly and downward. The ischium and pubis bones limit the large, oval shape obturator foramen , closed by a connective tissue obturator membrane. The pelvic bones articulate with the posterior sacrum , in front - with each other, forming a bony pelvis.
The skeleton of the free part of the lower limb is similar in structure to the skeleton of the upper limb and consists of three sections: the femur, the bones of the lower leg (tibia and fibula) and the bones of the foot (tarsal bones, metatarsals and phalanges of the fingers).
Lower limb belt,
- 1 Ilium
- 2 Hip [pelvic] bone
- 3 Femur
- 4 Patella
- 5 Fibula
- 6 Tibia
- 7 Foot bones
- 8 Ischium,
- 9 Pubic bone
The bones of the lower limb girdle also include the sacrum and coccygeal bones. The bones of the lower limb girdle connect and form the pelvis, which is the skeleton for the internal organs, a support for the torso and serves to connect with the part of the free lower limb.
Femur-- the largest tubular bone in the human body, upper (proximal) end (pineal gland) has a head that articulates with the pelvic bone. A long, thin neck connects the ball-shaped head to the body of the femur. At the junction of the neck and the body, the femur has two massive tubercles for muscle attachment. Lower epiphysis The femur is thickened. It bears two elevations - condyle, by means of which the femur articulates with the tibia and the patella, and two protruding to the sides epicondyle-- medial and lateral.
Patella is a large flattened bone that lies deep within the quadriceps tendon. With its posterior surface, the patella is adjacent to the lower end of the femur. The patella is an integral part of the knee joint.
Skeleton of the lower leg consists of two long tubular bones: the tibia and fibula. Tibia thicker than the fibula. Its upper end is massive and thick. It has articular surfaces for connection with the condyles of the femur and with the head of the fibula. The lower end of the fibula on the inner (medial) side continues into a flattened outgrowth - the medial malleolus. The anterior, pointed edge of the tibia is located directly under the skin.
Fibula thin, long, with thickened ends, located on the side (lateral) of the tibia. The upper end of the fibula forms an articulation with the lateral surface of the superior epiphysis of the tibia, and the lower end ends in the flattened lateral malleolus. The lateral malleolus, together with the medial malleolus and the lower surface of the tibia, participate in the formation of the ankle joint.
Foot bones, like the bones of the hand, are divided into three groups: tarsal bones, metatarsal bones and phalanges of the fingers.
Tarsal bones include seven bones arranged in two rows. The largest of them is the talus bone, which participates in the formation of the ankle joint, and the calcaneus bone lying underneath it. The other tarsal bones (cuboid, navicular, and three cuneiforms) are located anterior to the calcaneus and talus. Five short tubular metatarsal bones are located anterior to the tarsal bones. The first metatarsal bone is shorter and thicker than the others. Toe bones -- These are short tubular bones - phalanges. The big toe has two phalanges, the other four toes have three phalanges.
The lower limbs of a person can withstand heavy loads and completely take over the functions of movement. They have a more massive skeleton, large and stable joints and arched feet. Only humans have developed longitudinal and transverse arches of the foot. The fulcrum points of the foot are the heads of the metatarsal bones in front and the calcaneal tubercle in the back. Springy arches of the feet distribute the weight on the foot, reduce shocks and jolts when walking, and impart a smooth gait. The muscles of the lower limb have greater strength, but at the same time less variety in their structure than the muscles of the upper limb.
The skeleton of the upper and lower extremities is divided into the skeleton of the free limb and the skeleton of the belt. The skeleton of the upper limb girdle (shoulder girdle) consists of two paired bones - the scapula and the clavicle, and the skeleton of the free part of the upper limb - of three sections: the humerus, the bones of the forearm and the bones of the hand. The skeleton of the lower limb girdle (pelvic girdle) consists of a paired pelvic bone, and the skeleton of the free part of the lower limb is also divided into three sections: the femur, the bones of the lower leg and the bones of the foot. The skeleton of the upper limb is used to grasp and move objects in space, and the skeleton of the lower limbs is used for support and movement. Each bone is an independent organ that performs a specific function.
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Part of the body |
Name of bones and their number |
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Tulovise |
Vertebrae 31--33 breast 12 lumbar 5 sacrum (5 fused sacral vertebrae) coccyx (3--5 coccygeal vertebrae) Ribs 12 pairs |
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23 bones, including unpaired bones - frontal, occipital, sphenoid, lower jaw, hyoid bone and paired bones - parietal, temporal, zygomatic, etc. |
|
|
Upper limb |
32 bones in one upper limb brachial bone radius elbow bone carpal bones 8 metacarpal bones 5 phalanges of fingers 14 |
|
Lower limb |
31 bones in one lower limb hip bone femur patella tibia fibula tarsal bones 7 metatarsals 5 phalanges of fingers 14 |
Upper limb ossa membri superior consists of the shoulder girdle cingulum extremitas superiores and the free upper limb. The latter consists of the shoulder, forearm and hand. The bones of the shoulder girdle, consisting of the scapula and the clavicle, connect the upper limb to the axial skeleton.
This is one of the features of the human skeleton, which has a “grasping, climbing” type limb. This type of limb is characterized by the presence of a clavicle, which creates a fairly rigid connection with the axial skeleton.
In this way, humans differ from many other mammals (for example, ungulates, carnivores), which do not have a collarbone and the limb has a “running” type of structure.
The clavicle (clavicula) with its sternal end forms a joint with the sternum, and with its humeral end it forms a joint with the scapula - the acromial joint.
The shoulder blade (scapula) forms with the humerus - the shoulder joint - one of the most mobile joints of our skeleton (triaxial)
The sternoclavicular joint, articulatio sternoclavicularis, is formed by the clavicular notch of the sternum and the sternal end of the clavicle. The joint is simple (articulatio simplex). The articular surfaces are covered with connective tissue cartilage, are incongruent and most often have a saddle shape.
The shoulder joint, articulatio humeri, is formed by the glenoid cavity of the scapula, cavitas glenoidalis scapulae, and the head of the humerus, caput humeri. The articular surfaces are covered with hyaline cartilage and do not correspond to each other. The congruence of the articular surfaces is increased by the articular labrum, labrum glenoidale, which is located along the edge of the cavitas glenoidalis. The articular capsule, capsula articularis, is spacious and weakly stretched. The shoulder joint has only one coracohumeral ligament, lig. coracohumerale. It is a compaction of the fibrous layer of the capsule that extends from the outer edge of the coracoid process to the greater tubercle of the humerus. The shoulder joint in shape belongs to the spherical joints, articulatio spheroidea, with an extensive range of movements (3-axis joint)
The elbow joint, articulatio cubiti, is formed by the articular surface of the lower epiphysis of the humerus - its trochlea and head, the articular surfaces on the ulna - the trochlear and radial notches of the ulna, as well as the head and articular circumference of the radius. The joint is complex (articulatio composita). The articular surfaces are covered with hyaline cartilage. The articular capsule in the anterior and posterior parts of the joint is thin and weakly stretched, and in the lateral parts it is strengthened by ligaments. Its synovial membrane also covers those parts of the bones that are located in the joint cavity, but are not covered with cartilage (neck of the radius, etc.).
In the cavity of the elbow joint, three joints are distinguished: humeroulnar, brachioradial and proximal (upper) radioulnar. The humeral-ulnar joint, articulatio humeroulnaris, is located between the surface of the trochlea of the humerus and the trochlear notch of the ulna, is a type of trochlear joint and belongs to the screw-shaped joints. The humeroradial joint, articulatio humeroradialis, is formed by the head of the humerus and the fossa on the head of the radius and belongs to the spherical joints, articulatio spheroidea (in reality, movements in it are made not along three, but only two axes - frontal and vertical). Proximal radioulnar joint, articulatio radioulnaris proximalis, lies between the radial notch of the ulna and the articular circumference of the head of the radius and is a typical cylindrical joint. In the shoulder-elbow joint, flexion, flexio, and extension, extensio, are possible. which occur with simultaneous movement of the radius in the humeroradial joint. In the brachioradial joint, in addition, rotation, rotatio, of the radius occurs along its long axis, inward, pronatio, and outward, supinatio, as well as to a small extent adduction, and abduction; in the proximal radioulnar joint, rotation of the radial bone occurs with simultaneous movement in brachioradial joint.