ANATOMY OF SHOULDER JOINT
DR BIPUL BORTHAKUR
PROFESSOR & HOD
DEPARTMENT OF ORTHOPAEDICS,SMCH
Shoulder joint
 Shoulder joint is formed by articulation of the scapula (glenoid cavity) and head of the humerus
 Glenohumeral joint
Type of joint
 It is a synovial joint
 Polyaxial
 Ball and socket variety.
Proximal articular surface
Glenoid fossa of scapula :
 Pyriform in shape
 Surface area and concavity of the glenoid fossa is increased by glenoid
labrum
 Glenoid labrum – fibro cartilaginous ribbon like structure
 Covered with hyaline cartilage.
Distal articular surface
The head of humerus :
 Hemispherical in shape
 Covered with hyaline cartilage
Shoulder joint – weak point
 Glenoid fossa is too small and shallow to hold the head of humerus
 The head is four times the size of glenoid cavity
 Structurally it is a weak joint
Stability of the joint : Ligaments
True ligament : Capsule
Accessory ligaments :All the accessory ligaments attach either to lesser or
greater tubercles of humerus
 Glenohumeral ligaments
 Transverse humeral ligament
 Coraco-humeral ligament
 Secondary socket/ ligament ( Coracoacromial arch)
 Glenoid labrum
True ligament : Capsule
 Loose fibrous covering
 Inner surface lined with synovial membrane
Proximal attachments :
 Margins of glenoid fossa
Distal attachments :
 Anatomical neck of humerus
Accessory ligaments
Glenohumeral ligaments :
Three :
 Superior band
 Middle band
 Inferior band
 Seen on inner side of anterior part of capsule
Glenohumeral ligaments cont..
Proximal attachment : (Glenoid )
 All 3 bands attached to upper end of glenoid fossa
Distal attachment : (Humerus)
 Upper band : Top of lesser tubercle
 Middle band : Lesser tubercle deep to the tendon of subscapularis
 Lower band : Shaft just below the lesser tubercle
Transverse humeral ligament
 It is broad band which passes between the humeral tubercles
 It is attached superior to the epiphyseal line
 Long head of biceps tendon passes out deep to this ligament
Coraco-humeral ligament
 Origin - Lateral margin of root of coracoid process
 Insertion - greater tuberosity of humerus
Coracoacromial ligament
 Triangular band
Base : Attached to lateral margin of coracoid process
Apex : Attached to tip of acromion
 Coracoid process, ligament and acromion together form – Coracoacromial
arch (which forms secondary socket for the joint)
Glenoid labrum
 Fibro cartilaginous ribbon like structure
 Attached to margins of the glenoid cavity
 Increases the depth of the glenoid cavity.
 Lined by hyaline cartilage
Rotator cuff
 Laxity and weakness of joint is compensated by rotator cuff
Tendons of rotator cuff :
 Supraspinatus
 Infraspinatus
 Teres minor
 Subscapularis
Rotator cuff cont..
 Expansions from these tendons fuse with capsule
 Strengthens the capsule all around ( except inferiorly )
 Injury to rotator cuff result in recurrent dislocation .
Relations of shoulder joint
 Muscles
 Bursae
 Vessels and nerves
Relations of shoulder joint: Muscles
Anteriorly :
 Subscapularis
 Coracobrachialis
 Short head of biceps
 Deltoid
Posteriorly :
 Infraspinatus
 Teres minor
 Deltoid
Cont…
Superiorly :
 Long head of biceps inside the capsule
 Supraspinatus outside the capsule
Inferiorly :
 Long head of triceps
 Deltoid covers superiorly, anteriorly, posteriorly and laterally.
Bursae related to shoulder joint
Subacromial bursa :
 Lies between deltoid muscle and capsule
 Does not communicate with joint
 Extends between supraspinatus and acromion and coracoacromial arch
 Longest bursa in the body
Blood supply
Arterial supply :
 Anterior circumflex humeral artery
 Posterior circumflex humeral artery
 Suprascapular artery
 Circumflex scapular branch of subscapular artery
Venous drainage :
Corresponding veins
Nerve supply
 Lateral pectoral nerve
 Suprascapular nerve
 Axillary nerve (posterior division)
Movements at shoulder joint
 Flexion and extension
 Adduction and abduction
 Medial and lateral rotation
 Circumduction
Flexion and extension : Transverse
Axis
Flexors of shoulder joint :
 Pectoralis major (Clavicular part)
 Deltoid (anterior fibres)
 Coracobrachialis and assisted by biceps
Extensors of shoulder joint :
 Deltoid (posterior fibres )
 Teres major
 Latissimus dorsi and pectoralis major (sternocostal part)
Abduction and Adduction : Antero-
posterior axis
Abductors of shoulder joint :
 Supraspinatus :0-30
 Deltoid(middle fibres) : 0-90
 Serratus anterior and trapezius : 90-180
Adductors of shoulder joint :
 Pectoralis major
 Latissimus dorsi
 Teres major
 Coracobrachialis
 Biceps (short head )
Medial and lateral rotation :
Longitudinal axis
Medial rotation :
 Pectoralis major
 Deltoid (anterior fibres)
 Latissimus dorsi
 Teres major and subscapularis
Lateral rotation :
 Infraspinatus
 Deltoid (posterior fibres ) and teres minor
Circumduction
 Combination of 3 axis
 Combination of all the muscles around shoulder
Anterior glenohumeral dislocation
 Trauma to the upper extremity with the shoulder in abduction, extension,
and external rotation.
 BANKART lesion – Avulsion of anteroinferior labrum off the glenoid rim. It
may be associated with a glenoid rim fracture (Bony Bankart)
 Hills-Sachs lesion : A posterolateral head defect is caused by an
impression fracture on the glenoid rim.
Inferior glenohumeral
dislocation(Luxatio Erecta)
 Most common in elderly individuals.
 It results from a hyperabduction force causing impringement of the
humerus on the acromion which leaves the humeral head out inferiorly
 Patient typically present in salute fashion
 Humeral head is typically palpable on the lateral chest wall and axilla.
Rotator cuff disorders
 Impingement : The muscle most commonly involved is supraspinatus as it
passes beneath the acromion and the acromioclavicular ligament. This
space beneath which the supraspinatus tendon passes is of fixed
dimensions
Swelling of this muscle causes excessive fluid within the
subacromial/subdeltoid bursa or subacromial body spurs may produce
significant impingement when arm is abducted
Cont..
 Tendinopathy : The blood supply to the supraspinatus tendon is relatively
poor. Repeated trauma in certain circumstances makes the tendon
susceptible to degenerative changes which may result in calcium
deposition producing extreme pain
Subacromial bursitis
 It is inflammation of the bursa that separates the superior surface of the
supraspinatus tendon from the overlying coraco-acromial ligament,
acromion and coracoid and from the deep surface of the deltoid muscle.
THANK YOU

Anatomy of shoulder joint

  • 1.
    ANATOMY OF SHOULDERJOINT DR BIPUL BORTHAKUR PROFESSOR & HOD DEPARTMENT OF ORTHOPAEDICS,SMCH
  • 2.
    Shoulder joint  Shoulderjoint is formed by articulation of the scapula (glenoid cavity) and head of the humerus  Glenohumeral joint
  • 4.
    Type of joint It is a synovial joint  Polyaxial  Ball and socket variety.
  • 5.
    Proximal articular surface Glenoidfossa of scapula :  Pyriform in shape  Surface area and concavity of the glenoid fossa is increased by glenoid labrum  Glenoid labrum – fibro cartilaginous ribbon like structure  Covered with hyaline cartilage.
  • 7.
    Distal articular surface Thehead of humerus :  Hemispherical in shape  Covered with hyaline cartilage
  • 9.
    Shoulder joint –weak point  Glenoid fossa is too small and shallow to hold the head of humerus  The head is four times the size of glenoid cavity  Structurally it is a weak joint
  • 10.
    Stability of thejoint : Ligaments True ligament : Capsule Accessory ligaments :All the accessory ligaments attach either to lesser or greater tubercles of humerus  Glenohumeral ligaments  Transverse humeral ligament  Coraco-humeral ligament  Secondary socket/ ligament ( Coracoacromial arch)  Glenoid labrum
  • 11.
    True ligament :Capsule  Loose fibrous covering  Inner surface lined with synovial membrane Proximal attachments :  Margins of glenoid fossa Distal attachments :  Anatomical neck of humerus
  • 12.
    Accessory ligaments Glenohumeral ligaments: Three :  Superior band  Middle band  Inferior band  Seen on inner side of anterior part of capsule
  • 13.
    Glenohumeral ligaments cont.. Proximalattachment : (Glenoid )  All 3 bands attached to upper end of glenoid fossa Distal attachment : (Humerus)  Upper band : Top of lesser tubercle  Middle band : Lesser tubercle deep to the tendon of subscapularis  Lower band : Shaft just below the lesser tubercle
  • 14.
    Transverse humeral ligament It is broad band which passes between the humeral tubercles  It is attached superior to the epiphyseal line  Long head of biceps tendon passes out deep to this ligament
  • 15.
    Coraco-humeral ligament  Origin- Lateral margin of root of coracoid process  Insertion - greater tuberosity of humerus
  • 16.
    Coracoacromial ligament  Triangularband Base : Attached to lateral margin of coracoid process Apex : Attached to tip of acromion  Coracoid process, ligament and acromion together form – Coracoacromial arch (which forms secondary socket for the joint)
  • 18.
    Glenoid labrum  Fibrocartilaginous ribbon like structure  Attached to margins of the glenoid cavity  Increases the depth of the glenoid cavity.  Lined by hyaline cartilage
  • 20.
    Rotator cuff  Laxityand weakness of joint is compensated by rotator cuff Tendons of rotator cuff :  Supraspinatus  Infraspinatus  Teres minor  Subscapularis
  • 22.
    Rotator cuff cont.. Expansions from these tendons fuse with capsule  Strengthens the capsule all around ( except inferiorly )  Injury to rotator cuff result in recurrent dislocation .
  • 23.
    Relations of shoulderjoint  Muscles  Bursae  Vessels and nerves
  • 24.
    Relations of shoulderjoint: Muscles Anteriorly :  Subscapularis  Coracobrachialis  Short head of biceps  Deltoid Posteriorly :  Infraspinatus  Teres minor  Deltoid
  • 25.
    Cont… Superiorly :  Longhead of biceps inside the capsule  Supraspinatus outside the capsule Inferiorly :  Long head of triceps  Deltoid covers superiorly, anteriorly, posteriorly and laterally.
  • 27.
    Bursae related toshoulder joint Subacromial bursa :  Lies between deltoid muscle and capsule  Does not communicate with joint  Extends between supraspinatus and acromion and coracoacromial arch  Longest bursa in the body
  • 29.
    Blood supply Arterial supply:  Anterior circumflex humeral artery  Posterior circumflex humeral artery  Suprascapular artery  Circumflex scapular branch of subscapular artery Venous drainage : Corresponding veins
  • 31.
    Nerve supply  Lateralpectoral nerve  Suprascapular nerve  Axillary nerve (posterior division)
  • 33.
    Movements at shoulderjoint  Flexion and extension  Adduction and abduction  Medial and lateral rotation  Circumduction
  • 35.
    Flexion and extension: Transverse Axis Flexors of shoulder joint :  Pectoralis major (Clavicular part)  Deltoid (anterior fibres)  Coracobrachialis and assisted by biceps Extensors of shoulder joint :  Deltoid (posterior fibres )  Teres major  Latissimus dorsi and pectoralis major (sternocostal part)
  • 36.
    Abduction and Adduction: Antero- posterior axis Abductors of shoulder joint :  Supraspinatus :0-30  Deltoid(middle fibres) : 0-90  Serratus anterior and trapezius : 90-180 Adductors of shoulder joint :  Pectoralis major  Latissimus dorsi  Teres major  Coracobrachialis  Biceps (short head )
  • 37.
    Medial and lateralrotation : Longitudinal axis Medial rotation :  Pectoralis major  Deltoid (anterior fibres)  Latissimus dorsi  Teres major and subscapularis Lateral rotation :  Infraspinatus  Deltoid (posterior fibres ) and teres minor
  • 38.
    Circumduction  Combination of3 axis  Combination of all the muscles around shoulder
  • 39.
    Anterior glenohumeral dislocation Trauma to the upper extremity with the shoulder in abduction, extension, and external rotation.  BANKART lesion – Avulsion of anteroinferior labrum off the glenoid rim. It may be associated with a glenoid rim fracture (Bony Bankart)  Hills-Sachs lesion : A posterolateral head defect is caused by an impression fracture on the glenoid rim.
  • 40.
    Inferior glenohumeral dislocation(Luxatio Erecta) Most common in elderly individuals.  It results from a hyperabduction force causing impringement of the humerus on the acromion which leaves the humeral head out inferiorly  Patient typically present in salute fashion  Humeral head is typically palpable on the lateral chest wall and axilla.
  • 41.
    Rotator cuff disorders Impingement : The muscle most commonly involved is supraspinatus as it passes beneath the acromion and the acromioclavicular ligament. This space beneath which the supraspinatus tendon passes is of fixed dimensions Swelling of this muscle causes excessive fluid within the subacromial/subdeltoid bursa or subacromial body spurs may produce significant impingement when arm is abducted
  • 42.
    Cont..  Tendinopathy :The blood supply to the supraspinatus tendon is relatively poor. Repeated trauma in certain circumstances makes the tendon susceptible to degenerative changes which may result in calcium deposition producing extreme pain
  • 43.
    Subacromial bursitis  Itis inflammation of the bursa that separates the superior surface of the supraspinatus tendon from the overlying coraco-acromial ligament, acromion and coracoid and from the deep surface of the deltoid muscle.
  • 44.