The document summarizes key aspects of the shoulder joint, including that it is a ball and socket synovial joint formed by the head of the humerus and glenoid cavity of the scapula. It describes the articular surfaces, ligaments like the glenohumeral and rotator cuff, relations to muscles and bursae, blood supply from circumflex arteries, nerve supply including branches of axillary nerve, and movements including flexion, extension, and rotation. It also discusses clinical relevance to conditions like dislocation, bursitis, tendinitis, and rotator cuff injuries.

1. Shoulder Joint
Lecture by
Dr.N.Mugunthan.MBBS,MS,DNB,MNAMS,PhD
Associate Professor,
MGMC&RI.
© Dr.N.Mugunthan 1

2. Learning objectives
Shoulder joint:
• Type & variety
• Articular surfaces
• Ligaments
• Relations
• Blood & nerve supply
• Movements
• Applied anatomy
LAQ: Describe the shoulder joint under following headings: a. articular
surfaces b. ligaments c. movements d. applied anatomy (2+3+3+2)© Dr.N.Mugunthan 2

3. How to describe a joint
9. Movements
10. Muscles producing
movements
11. Unique features of
particular joint
12. Applied anatomy
1. Definition
2. Type of joint
3. Variety of joint
4. Articular surfaces
5. Ligaments
6. Relations
7. Blood supply
8. Nerve supply © Dr.N.Mugunthan 3

4. Shoulder joint
Definition :
 Shoulder joint is formed
by articulation of the
scapula (glenoid cavity)
and head of the
humerus
 Glenohumeral joint
© Dr.N.Mugunthan 4

5. Type of joint
Synovial joint
Polyaxial
© Dr.N.Mugunthan 5

6. Variety of joint
Ball and socket
variety
© Dr.N.Mugunthan 6

7. Articular surfaces
Proximal articular surface :
Glenoid fossa of scapula
 Pyriform in shape
 Surface area, concavity
of glenoid fossa
increased by glenoidal
labrum
 Glenoidal labrum – fibro
cartilaginous ribbon like
structure
 Covered with hyaline
cartilage
© Dr.N.Mugunthan 7

8. Articular surfaces cont…
Distal articular surface:
The head of humerus
Hemispherical in
shape
Covered with hyaline
cartilage
© Dr.N.Mugunthan 8

9. Shoulder joint – weak joint
o Glenoid fossa is too small
& shallow
o to hold the head of the
humerus in place
o The head is four times
the size of glenoid cavity
o Structurally, it is a weak
joint
Stability of the joint is ?
© Dr.N.Mugunthan 9

10. Ligaments
1. Capsule
2. Glenohumeral ligaments
3. Transverse humeral
ligament
4. Coracohumeral ligament
5. Secondary socket /
ligament
(Coracoacromial arch)
6. Glenoidal labrum
© Dr.N.Mugunthan 10

11. Capsule
Loose fibrous covering
Inner surface lined with
synovial membrane
Attachments:
Proximal attachments:
Margins of glenoid fossa
(proximal to glenoid
labrum)
Distal attachments:
Anatomical neck of
humerus (except inferiorly,
extends to shaft for
1.25cm) © Dr.N.Mugunthan 11

12. Weakness of the capsule
 Lax and weak
Capsule is deficient at
3places
Superiorly - for passage the
tendon of the long head of
the biceps brachii.
Anteromedial side – joint
communicates with
subscapular bursa
Posterolateral side –
communicates with bursa
under infraspinatus
tendon © Dr.N.Mugunthan 12

13. Capsule
© Dr.N.Mugunthan 13

14. Glenohumeral ligaments :
Three :
1. Superior band
2. Middle band
3. Inferior band
Seen on inner side of
ant. part of capsule
Ligaments cont…
© Dr.N.Mugunthan 14

15. Attachments :
Proximally: (Glenoid)
 All 3 bands attached to
upper end of glenoid
fossa
Distal : (Humerus)
 Upper band – top of
lesser tuberosity
 Middle band – lower
part
 Lower band – shaft just
below lesser tuberosity
Glenohumeral ligaments cont…
© Dr.N.Mugunthan 15

16. Transverse humeral ligament
Stretches between tops
of greater & lesser
tuberosities
Long head of biceps
tendon passes out deep
to this ligament
© Dr.N.Mugunthan 16

17. Coracohumeral ligament
Attachment :
Lateral margin of root of
coracoid process to
Greater tuberosity of
humerus
All the accessory ligaments
attach either lesser/greater
tuberosity of humerus
© Dr.N.Mugunthan 17

18. Coracoacromial ligament
(secondary socket)
Triangular band
Base –attached to lateral
margin of coracoid
process
Apex – attached to tip of
acromion
Coracoid process,ligament
& acromion together form
– coracoacromial arch
Which forms secondary
socket for the joint
© Dr.N.Mugunthan 18

19. Rotator cuff
(Codman’s musculo-tendinous cuff)
Laxity & weakness of
joint is compensated
by this cuff
Derived from tendons
of – SITS
1. Supraspinatus
2. Infraspinatus
3. Teres minor
4. Subscapularis © Dr.N.Mugunthan 19

20. Expansions from these
tendons fuse with
capsule
Strengthens the
capsule all round
(except inferiorly)
Injury to rotator cuff –
recurrent dislocation
Rotator cuff cont…
(Codman’s musculo-tendinous cuff)
© Dr.N.Mugunthan 20

21. Rotator cuff
© Dr.N.Mugunthan 21

22. Glenoidal labrum
Fibro cartilaginous ribbon
like structure
Attached to margins of
the glenoid cavity
Increase the depth of
glenoid cavity
Increase the articular
surface of glenoid
Lined with hyaline
cartilage
© Dr.N.Mugunthan 22

23. Relations of shoulder joint
a) Muscles
b) Bursae
c) Vessels & nerves
© Dr.N.Mugunthan 24

24. a) Muscles:
Anteriorly:
• Subscapularis,
coracobrachialis, short
head of biceps and
deltoid.
Posteriorly:
• Infraspinatus, teres
minor and deltoid.
Relations of shoulder joint
© Dr.N.Mugunthan 25

25. a) Muscles: cont…
Superiorly:
• Long tendon of biceps
inside the capsule
• Supraspinatus outside
the capsule
Inferiorly:
• Long head of the triceps
 Deltoid – covers
superiorly, anteriorly,
posteriorly & laterally
Relations of shoulder joint
cont…
© Dr.N.Mugunthan 26

26. Subacromial (Subdeltoid)
bursa:
 Lies between deltoid
muscle & capsule
 Does not communicate
with joint
 Extends between
supraspinatus and
acromion & coracoacromial
arch
Longest bursa in the body
b) Bursae related to shoulder joint cont…
© Dr.N.Mugunthan 28

27. C) Vessels & nerves related to shoulder
joint
Posterior circumflex
humeral vessels
Axillary/ circumflex
nerve
 Related to inferior
part of capsule
© Dr.N.Mugunthan 30

28. Blood supply
Arterial supply:
 Anterior circumflex
humeral artery
 Posterior circumflex
humeral artery
 Suprascapular artery
 Circumflex scapular
branch of Subscapular
artery.
Venous drainage :
 Corresponding veins
© Dr.N.Mugunthan 31

29. Nerve supply
A twig from lateral
pectoral nerve
Suprascapular nerve
Axillary nerve
(posterior division)
© Dr.N.Mugunthan 32

30. Movements @ shoulder joint
Flexion & extension
Adduction & abduction
Medial & lateral rotation
Circumduction
© Dr.N.Mugunthan 33

31. Movements @ shoulder joint
© Dr.N.Mugunthan 34

32. Flexion & extension
Transverse axis :
Flexion:
• Pectoralis major
(clavicular part),
• Deltoid (anterior fibres)
coracobrachialis
• Assisted by biceps.
Extension:
• Deltoid (posterior fibres)
• Teres major,
• Latissimus dorsi and
pectoralis major
(sternocostal part)
© Dr.N.Mugunthan 35

33. Abduction & adduction
Antero-posterior axis
Abduction:
• Supraspinatus : 0-30°
• Deltoid (middle fibers)
30-90°
• Serratus anterior &
trapezius: 90-180°
Adduction:
• Pectoralis major
• Latissimus dorsi
• Teres major
• Corachobrachialis
• Biceps (short head)
© Dr.N.Mugunthan 36

34. Medial & 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. © Dr.N.Mugunthan 37

35. Circumduction
• Combination of 3 axis
• Combination of all the
muscles around
shoulder
© Dr.N.Mugunthan 38

36. Muscles producing movements
© Dr.N.Mugunthan 39

37. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &C5) to
tip of shoulder via
supraclavicular nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 40

38. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 41

39. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 42

40. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus tendinitis &
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 43

41. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 44

42. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 45

43. Applied anatomy
• Referred pain from
diaphragm, pleura &
peritoneum (supplied by
phrenic nerve -C3,C4 &) to tip
of shoulder via supraclavicular
nerve (C3&C4)
• Dislocation
• Bursitis
• Supraspinatus Tendinitis
• Rupture of supraspinatus
• Rotator cuff injury
• Frozen shoulder
• Arthroscopy & arthroplasty
© Dr.N.Mugunthan 46

44. Arthroscopy shoulder joint -normal
© Dr.N.Mugunthan 47

45. Arthroscopy –rotator cuff repair
© Dr.N.Mugunthan 48

46. Take home message
Shoulder joint:
• Type & variety
• Articular surfaces
• Ligaments
• Relations
• Blood & nerve supply
• Movements
• Applied anatomy
© Dr.N.Mugunthan 49

47. © Dr.N.Mugunthan 50