ExperimentalManualofHumanAnatomythreeborders, andthree angles.Two surfaces aretheanteriorand theposterior.Theanteriorocostal surface is concave and known as the subscapularfossa.The posterior or dorsal surface isarched and is subdivided into two parts by the spine of scapula, the portion above the spine iscalled the supraspinous fossa, and thatbelowthe spineistheinfraspinous fossaThe spine ofscapula is a triangular crest which extends laterally to the acromion. The acromion is a triangularplate, with an oval facet towards medially to articulate with the clavicle. Three borders are thesuperior,the medial and thelateral.Thelateral part of superior border presents the scapularnotch. Lateral to the notch is the coracoid process which projects forwards. The medial border isalso called vertebral border. The lateral or axillary border is thick. Three angles include thesuperior, the inferior and the lateral. The superior angle is between the superior and medialborders,and is at the level of the2nd rib.The inferior angle is between the medial and lateraborders, at the level of the 7th rib or 7th intercostal space. It is a landmark for determination of thesequential order of ribs in the back. The lateral angle is broad and bears the pear-shaped glenoidcavity.Above andbelowthe cavity aretwo roughprocesses, the supraglenoid tubercleandinfraglenoidtubercle.Thethree largeprocesses ofthe scapula, i.ethe spine of scapula, theacromion and the coracoid process, with its inferior angle can be palpated by yourselfIL.Bones offreeupperlimbThe bones of free upper limb include the humerus in the arm; the ulna and radius in theforearm, and the carpal bones, the metacarpal bones and the phalanges of fingers in the hand1.HumerusThe humerus, thelongest and largest bone of the upper limb, lies in the arm.It is a long boneand has an upper end, a lower end and a body or shaft.The upper end bears the head of humerus which is nearly hemispherical in shape, and isdirected medially,backwards and upwards.The line separating thehead from the rest of upper endis termed as the anatomical neck. Distal to the neck are two tubercles on the upper end, the lateralone is thegreater tubercle, and the anterior one the lesser tubercle.The crest of greater tubercle21
Experimental Manual of Human Anatomy 21 three borders, and three angles. Two surfaces are the anterior and the posterior. The anterior or costal surface is concave and known as the subscapular fossa. The posterior or dorsal surface is arched and is subdivided into two parts by the spine of scapula, the portion above the spine is called the supraspinous fossa, and that below the spine is the infraspinous fossa. The spine of scapula is a triangular crest which extends laterally to the acromion. The acromion is a triangular plate, with an oval facet towards medially to articulate with the clavicle. Three borders are the superior, the medial and the lateral. The lateral part of superior border presents the scapular notch. Lateral to the notch is the coracoid process which projects forwards. The medial border is also called vertebral border. The lateral or axillary border is thick. Three angles include the superior, the inferior and the lateral. The superior angle is between the superior and medial borders, and is at the level of the 2nd rib. The inferior angle is between the medial and lateral borders, at the level of the 7th rib or 7th intercostal space. It is a landmark for determination of the sequential order of ribs in the back. The lateral angle is broad and bears the pear-shaped glenoid cavity. Above and below the cavity are two rough processes, the supraglenoid tubercle and infraglenoid tubercle. The three large processes of the scapula, i. e the spine of scapula, the acromion and the coracoid process, with its inferior angle can be palpated by yourself. II. Bones of free upper limb The bones of free upper limb include the humerus in the arm; the ulna and radius in the forearm, and the carpal bones, the metacarpal bones and the phalanges of fingers in the hand. 1. Humerus The humerus, the longest and largest bone of the upper limb, lies in the arm. It is a long bone and has an upper end, a lower end and a body or shaft. The upper end bears the head of humerus which is nearly hemispherical in shape, and is directed medially, backwards and upwards. The line separating the head from the rest of upper end is termed as the anatomical neck. Distal to the neck are two tubercles on the upper end, the lateral one is the greater tubercle, and the anterior one the lesser tubercle. The crest of greater tubercle
ExperimentalManualofHumanAnatomyandthecrestoflessertuberclearethedownwardprolongationsofthegreaterandlessertuberclesrespectively.Between the two tubercles runs a longitudinal groove, the intertubercular groove orsulcus.Distal to the tubercles is a constricted part, known as the surgical neck,which liesbetween the metaphysis and the shaft, lodges the axillary nerve and the posterior circumflexbrachial artery: The shaft is almost rounded in the upper half and triangular in the lower half. Alittle above the middle, a rough V-shaped area called deltoid tuberosity appears on theanterolateral surface.On themiddle part ofthe posterior surface,a spiral grooveknown as thesulcus forradial nerve runs obliquely downwards, laterally and forwardsto theanterolateralsurface, and transmits the radial nerve and the deep brachial artery.The lower endof humerus is flat and has two articular surfaces,the lateral one is the roundedcapitulum ofhumerusfor articulating with the head of radius toformthe humeroradial joint,andthe medial, is the spoon-shaped trochlea of humerus. Above the trochlea there is a coronoidfossa for the coronoid process of the ulna anteriorly anda deep olecranon fossa for the olecranonof the ulna posteriorly.Twoprojectionson eitherside of thelowerend are called the lateralepicondyle and the media epicondyle, respectively.The sulcus for ulnar nerve liesposteroinferior to themedial epicondyle, and accommodates the ulnar nerve.The lateral and medial epicondyles, and the greater tubercle of humerus can be palpated2.RadiusThe radius lies in the lateral part of the forearm. It is a long bone, and is divided into a body oshaft andtwo ends.Theupper end is head of radius.Distal to the head is a constricted partknown as the radius neck.The lower end is large and is quadrilateral in shape.The styloidprocess and head of the radius are palpable.3. UlnaTheulna is situated on the medial side ofthe radius in the forearm.It is also a long boneand idivisible into a body or shaft and two ends.The upper or proximal end is large and presents twoprocesses, the olecranon projecting upwards and forwards, and the coronoid process projecting22
Experimental Manual of Human Anatomy 22 and the crest of lesser tubercle are the downward prolongations of the greater and lesser tubercles, respectively.Between the two tubercles runs a longitudinal groove, the intertubercular groove or sulcus. Distal to the tubercles is a constricted part, known as the surgical neck, which lies between the metaphysis and the shaft, lodges the axillary nerve and the posterior circumflex brachial artery. The shaft is almost rounded in the upper half and triangular in the lower half. A little above the middle, a rough V-shaped area called deltoid tuberosity appears on the anterolateral surface. On the middle part of the posterior surface, a spiral groove known as the sulcus for radial nerve runs obliquely downwards, laterally and forwards to the anterolateral surface, and transmits the radial nerve and the deep brachial artery. The lower end of humerus is flat and has two articular surfaces, the lateral one is the rounded capitulum of humerus for articulating with the head of radius to form the humeroradial joint, and the medial, is the spoon-shaped trochlea of humerus. Above the trochlea there is a coronoid fossa for the coronoid process of the ulna anteriorly and a deep olecranon fossa for the olecranon of the ulna posteriorly. Two projections on either side of the lower end are called the lateral epicondyle and the media epicondyle, respectively. The sulcus for ulnar nerve lies posteroinferior to the medial epicondyle, and accommodates the ulnar nerve. The lateral and medial epicondyles, and the greater tubercle of humerus can be palpated. 2. Radius The radius lies in the lateral part of the forearm. It is a long bone, and is divided into a body or shaft and two ends. The upper end is head of radius. Distal to the head is a constricted part, known as the radius neck. The lower end is large and is quadrilateral in shape. The styloid process and head of the radius are palpable. 3. Ulna The ulna is situated on the medial side of the radius in the forearm. It is also a long bone and is divisible into a body or shaft and two ends. The upper or proximal end is large and presents two processes, the olecranon projecting upwards and forwards, and the coronoid process projecting
ExperimentalManualofHumanAnatomyforwards belowtheolecranon.Thetrochlear notch is a curved area formed bythe anteriorsurfaceof olecranon and the superiorsurface ofcoronoidprocess.Thedepression on thelateralside ofcoronoid process is the radial notch.Anteroinferior tothe coronoidprocessis theulnartuberosity. It has three borders,the anterior, posterior and lateral, and three surfaces,the anterior,posterior and medial. The lateral border is sharp and is called the interosseous border. The loweror distal end of ulna is made up of the head and styloid process.The head of ulna is rounded, andarticulates withtheulnarnotchof radius toform the inferiorradioulnar joint.It is separated fromthe wrist jointby an articular disc.The styloid process of ulna projects downwards fromtheposteromedial side of the lower end.The olecranon, styloid process and head of the ulna are palpable.4.Bones of handThe bones of hand include three parts, the carpal bones, metacarpal bones, and phalanges offingers.(1)Carpal bonesThe carpal bones are eight in number, and are arranged in two rows. Those in the proximal row,from theradial to the ulnar side,are named the scaphoid bone,lunatebone,triquetralbone,andpisiformbone, of which theformer threetogetherformthe distal articular surfaceof thewristjoint.Thedistalrowcontains,in the same order,thetrapezium bone,trapezoid bone,capitatebone, and hamate bone. They are short bones, each of them is roughly cuboidal in shape and hassix surfaces.The carpal bones arenotarranged in a same coronal plane,thedorsal surfaceofthemisroughlyconvex,butthepalmarsurfaceformsadeepconcavitycalledthecarpalgroove(2) Metacarpal bonesThemetacarpal bonesarefive innumber and numbered onetofivefromlateral tomedial sideEach of them is a long bone and has abase at the proximal end, a head placed distally,and a bodyor shaft inbetween.Thefirstmetacarpal bone is shorter and stouter than the others,and itsbase issaddle shaped for articulating with the trapezium bone23
Experimental Manual of Human Anatomy 23 forwards below the olecranon. The trochlear notch is a curved area formed by the anterior surface of olecranon and the superior surface of coronoid process. The depression on the lateral side of coronoid process is the radial notch. Anteroinferior to the coronoid process is the ulnar tuberosity. It has three borders,the anterior, posterior and lateral, and three surfaces,the anterior, posterior and medial. The lateral border is sharp and is called the interosseous border. The lower or distal end of ulna is made up of the head and styloid process. The head of ulna is rounded, and articulates with the ulnar notch of radius to form the inferior radioulnar joint. It is separated from the wrist joint by an articular disc. The styloid process of ulna projects downwards from the posteromedial side of the lower end. The olecranon, styloid process and head of the ulna are palpable. 4. Bones of hand The bones of hand include three parts, the carpal bones, metacarpal bones, and phalanges of fingers. (1) Carpal bones The carpal bones are eight in number, and are arranged in two rows. Those in the proximal row, from the radial to the ulnar side, are named the scaphoid bone, lunate bone, triquetral bone, and pisiform bone, of which the former three together form the distal articular surface of the wrist joint. The distal row contains, in the same order, the trapezium bone, trapezoid bone, capitate bone, and hamate bone. They are short bones, each of them is roughly cuboidal in shape and has six surfaces. The carpal bones are not arranged in a same coronal plane, the dorsal surface of them is roughly convex, but the palmar surface forms a deep concavity called the carpal groove. (2) Metacarpal bones The metacarpal bones are five in number and numbered one to five from lateral to medial side. Each of them is a long bone and has a base at the proximal end, a head placed distally, and a body or shaft in between. The first metacarpal bone is shorter and stouter than the others, and its base is saddle shaped for articulating with the trapezium bone
ExperimentalManualofHumanAnatomy(3) Phalanges offingersThephalanges of fingers arefourteen in number,each ofthemedial fourfingers has threecalled the proximal phalanx, middle phalanx and distal phalanx, respectively, but the thumb hasonlytwo,theproximal andthedistal.Eachphalanxisalongboneand consists of abodyorshaftand two ends. The proximal end is called the base, the distal end is the head, and the shaft liesbetween the base and head.On the proximal and middlephalanges, the head bears thetrochlea ofphalanx,but the head of distal phalanx is non-articular and called the tuberosity of distal phalanxSection 2 Joints of upper limbThe articulations of the upper limb include both those of the girdle and those of the free upperlimb.Usingarticulatedvertebraetoobservethefollowing structures1.Articulationsofgirdleofupperlimb(l)SternoclavicularjointIt is the only synovial joint between the upper limb and thetrunk.It isa type of saddle jointwhich is formed bythe sternal extremity of theclavicle and the clavicular notch ofthe sternum.Itscapsule is strengthened by several ligaments.The anterior and the posterior sternoclavicularligaments, the interclavicular ligament and the costoclavicular ligament. They support thesternoclavicular joint and provide flexibilitytomovein different directions.The articular cavity isdivided by an articular discinto two entirely separate compartments. The joint allows the shoulderto be moved upand down, forward and backward.Italso permits circumduction(2)AcromioclavicularjointIt is a plane joint between the acromial end of the clavicle and the medial margin of the acromionof the scapula. The joint capsule is strengthened above by theacromioclavicular ligament andbelow by thecoracoclavicular ligament.Although the range ofmovement of this joint is small, itplays important roles in the movements of the upper extremity(3) Coracoacromial ligament24
Experimental Manual of Human Anatomy 24 (3) Phalanges of fingers The phalanges of fingers are fourteen in number, each of the medial four fingers has three, called the proximal phalanx, middle phalanx and distal phalanx, respectively; but the thumb has only two, the proximal and the distal. Each phalanx is a long bone and consists of a body or shaft and two ends. The proximal end is called the base, the distal end is the head, and the shaft lies between the base and head. On the proximal and middle phalanges, the head bears the trochlea of phalanx; but the head of distal phalanx is non-articular and called the tuberosity of distal phalanx. Section 2 Joints of upper limb The articulations of the upper limb include both those of the girdle and those of the free upper limb. Using articulated vertebrae to observe the following structures. 1. Articulations of girdle of upper limb (1)Sternoclavicular joint It is the only synovial joint between the upper limb and the trunk. It is a type of saddle joint, which is formed by the sternal extremity of the clavicle and the clavicular notch of the sternum. Its capsule is strengthened by several ligaments. The anterior and the posterior sternoclavicular ligaments, the interclavicular ligament and the costoclavicular ligament. They support the sternoclavicular joint and provide flexibility to move in different directions. The articular cavity is divided by an articular discinto two entirely separate compartments. The joint allows the shoulder to be moved up and down, forward and backward. It also permits circumduction. (2)Acromioclavicular joint It is a plane joint between the acromial end of the clavicle and the medial margin of the acromion of the scapula. The joint capsule is strengthened above by theacromioclavicular ligament and below by thecoracoclavicular ligament.Although the range of movement of this joint is small, it plays important roles in the movements of the upper extremity. (3) Coracoacromial ligament
ExperimentalManualofHumanAnatomyThisligament serves to connecttheclavicle withthe coracoidprocess of the scapulaIt isatriangular ligament and prevents the shoulder jointfrom upward dislocation2.ArticulationsoffreeupperlimbThe articulations of the free upper limb include the shoulder joint, the elbow joint, the joints ofthe ulna and the radius, the wrist joint and the joints of the hand(1) ShoulderjointThe shoulder join is a typical ball and socket synovial joint and has the greatest freedom ofmovement.It is formed bythe head of the humerus and theglenoid cavityof the scapula.A circularband of fibrocartilage called the glenoid labrum deepens the concavity of the glenoid cavity. A thinand loosefibrouscapsulecompletelyencirclesthejoint.Itbridgesbetweenthemarginoftheglenoidcavity and theanatomical neck of thehumerus.The synovial bursae andtendon sheathes enhancethe freedom of movement.The tendon of the long head of the biceps brachii passes through thecapsule. The shoulder joint is strengthened superiorly by the tendon of supraspinatus and thecoracohumeral ligament (a thickened part of the fibrous capsule between the base ofthe coracoidprocess and the greater tubercle of the humerus), anteriorly by the glenohumeral ligaments andtendon of the subscapularis anteriorly, and posteriorly by the tendons of infraspinatus and teresminor posteriorly.The stability of the shoulder joint is depended mainly on the actions of thesurrounding muscles. There is no muscular protection at the anteroinferior aspect of the joint. Sodislocation of the humeral head usually occurs in this direction.Not only does it have the greatest freedom of movement, the shoulder joint also allows a widerangeofmovements,suchasflexion,extension,abduction,adduction,circumductionandrotationIt rotates medially and laterally on the long axis of the humerus(2)ElbowjointTheelbow joint is a compound synovial joint.It consists of three joints:the humeroulnar joint,humeroradial joint and the proximal radioulnar joint.The humeroulnar joint is formed by thetrochlea of the humerus with the trochlear notch of the ulna.The humeroradial joint is formed by25
Experimental Manual of Human Anatomy 25 This ligament serves to connect the clavicle with the coracoid process of the scapula. It is a triangular ligament and prevents the shoulder joint from upward dislocation. 2. Articulations of free upper limb The articulations of the free upper limb include the shoulder joint, the elbow joint, the joints of the ulna and the radius, the wrist joint and the joints of the hand. (1) Shoulder joint The shoulder join is a typical ball and socket synovial joint and has the greatest freedom of movement. It is formed by the head of the humerus and the glenoid cavity of the scapula.A circular band of fibrocartilage called the glenoid labrum deepens the concavity of the glenoid cavity. A thin and loose fibrous capsule completely encircles the joint. It bridges between the margin of the glenoid cavity and the anatomical neck of the humerus. The synovial bursae and tendon sheathes enhance the freedom of movement. The tendon of the long head of the biceps brachii passes through the capsule. The shoulder joint is strengthened superiorly by the tendon of supraspinatus and the coracohumeral ligament (a thickened part of the fibrous capsule between the base of the coracoid process and the greater tubercle of the humerus), anteriorly by the glenohumeral ligaments and tendon of the subscapularis anteriorly, and posteriorly by the tendons of infraspinatus and teres minor posteriorly. The stability of the shoulder joint is depended mainly on the actions of the surrounding muscles. There is no muscular protection at the anteroinferior aspect of the joint. So dislocation of the humeral head usually occurs in this direction. Not only does it have the greatest freedom of movement, the shoulder joint also allows a wide range of movements, such as flexion, extension, abduction,adduction, circumduction and rotation. It rotates medially and laterally on the long axis of the humerus. (2) Elbow joint The elbow joint is a compound synovial joint. It consists of three joints: the humeroulnar joint, humeroradial joint and the proximal radioulnar joint. The humeroulnar joint is formed by the trochlea of the humerus with the trochlear notch of the ulna. The humeroradial joint is formed by