This document discusses the anatomy and classification of joints in the human body. It begins by classifying joints based on their function and structure. There are three main types of joints based on function: synarthroses (immovable), amphiarthroses (slightly movable), and diarthroses (freely movable). The document then discusses the four main structural classifications of joints: fibrous, cartilaginous, synovial, and bony. It provides examples and descriptions of different joint types within each structural classification. The majority of the document focuses on the anatomy and features of synovial joints, which are the most common and complex type of joint in the body.

1. ANATOMY OF JOINTS
By- Dr. Armaan SinghBy- Dr. Armaan Singh

2. CLASSIFICATION OF JOINTS
 Functional classification
(Focuses on amount of movement)
 Synarthroses (immovable joints)
 Amphiarthroses (slightly movable joints)
 Diarthroses (freely movable joints)
 Structural classification
(Based on the material binding them and presence or absence of a
joint cavity)
 Bony fusion
 Fibrous
 Cartilagenous
 Synovial

3. TABLE OF JOINT TYPES
Functional across
Structural down
Synarthroses
(immovable joints)
Amphiarthroses
(some movement)
Diarthroses
(freely movable)
Bony Fusion Synostosis
(frontal=metopic
suture; epiphyseal
lines)
Fibrous Suture (skull only)
-fibrous tissue is
continuous with
periosteum
Gomphoses (teeth)
-ligament is
periodontal ligament
Syndesmoses
-ligaments only
between bones; here,
short so some but not
a lot of movement
(example: tib-fib
ligament)
Syndesmoses
-ligament longer
(example: radioulnar
interosseous
membrane)
Cartilagenous
(bone united by
cartilage only)
Synchondroses
-hyaline cartilage
(examples:
manubrium-C1,
epiphyseal plates)
Sympheses
-fibrocartilage
(examples: between
discs, pubic
symphesis
Synovial Are all diarthrotic

4. FIBROUS JOINTS
 Bones connected by fibrous tissue: dense regular connective tissue
 No joint cavity
 Slightly immovable or
not at all
 Types
 Sutures
 Syndesmoses
 Gomphoses

5. SUTURES
 Only between bones of skull
 Fibrous tissue continuous with periosteum
 Ossify and fuse in middle age: now
technically called “synostoses”= bony
junctions

6. SYNDESMOSES
 In Greek: “ligament”
 Bones connected by
ligaments only
 Amount of movement
depends on length of
the fibers: longer than
in sutures

7. GOMPHOSES
 Is a “peg-in-socket”
 Only example is tooth
with its socket
 Ligament is a short
periodontal ligament

8. CARTILAGENOUS JOINTS
 Articulating bones united by cartilage
 Lack a joint cavity
 Not highly movable
 Two types
 Synchondroses (singular: synchondrosis)
 Sympheses (singular: symphesis)

9. SYNCHONDROSES
 Literally: “junction of cartilage”
 Hyaline cartilage unites the bones
 Immovable (synarthroses)
 Examples:
 Epiphyseal plates
 Joint between first rib’s costal cartilage and manubrium of the sternum

10. SYMPHESES
 Literally “growing together”
 Fibrocartilage unites the bones
 Slightly movable (amphiarthroses)
 Resilient shock absorber
 Provide strength and flexibility
 Hyaline cartilage on articular surfaces of bones to reduce
friction
 Examples
 Intervertebral discs
 Pubic symphysis of the pelvis

11. SYNCHONDROSES AND SYMPHESES
Also pubic symphsis

12. SYNOVIAL JOINTS
 Include most of the body’s joints
 All are diarthroses (freely movable)
 All contain fluid-filled joint cavity

13. GENERAL STRUCTURE OF SYNOVIAL
JOINTS
1. Articular cartilage
 Hyaline
 Spongy cushions absorb
compression
 Protects ends of bones from
being crushed
2. Joint (synovial) cavity
 Potential space
 Small amount of synovial fluid

14. GENERAL STRUCTURE OF SYNOVIAL JOINTS
(CONT.)
3. Articular (or joint) capsule
 Two layered
 Outer*: fibrous capsule of dense
irregular connective tissue
continuous with periosteum
 Inner*: synovial membrane of
loose connective tissue (makes
synovial fluid)
 Lines all internal joint surfaces not
covered by cartilage*
*
*
*

15. GENERAL STRUCTURE OF SYNOVIAL JOINTS
(CONT.)
4. Synovial fluid
 Filtrate of blood
 Contains special glycoproteins
 Nourishes cartilage and functions as
slippery lubricant
 “Weeping” lubricatioin
5. Reinforcing ligaments (some joints)
 Capsular (most) – thickened parts of
capsule
 Extracapsular
 Intracapsular

16. GENERAL STRUCTURE OF SYNOVIAL JOINTS
(CONT.)
6. Nerves
 Detect pain
 Monitor stretch (one of the ways
of sensing posture and body
movements)
7. Blood vessels
 Rich blood supply
 Extensive capillary beds in
synovial membrane (produce the
blood filtrate)

17. GENERAL STRUCTURE OF SYNOVIAL
JOINTS

18. SOME JOINTS…
 Articular disc or
meniscus
(literally “crescent”)
 Only some joints
 Those with bone
ends of different
shapes or fitting poorly
 Some to allow two kinds of movement (e.g. jaw)
 Of fibrocartilage
 Examples: knee
TMJ (temporomandibular joint)

19. BURSAE AND TENDON SHEATHS
 Contain synovial fluid
 Not joints but often associated with them
 Act like ball bearings
 Bursa means “purse” in Latin
 Flattened sac lined by synovial membrane
 Where ligaments, muscles, tendons, or bones overlie each other and rub together
 Tendon sheath
 Only on tendons subjected to friction

20. BURSAE AND TENDON SHEATHS

21. JOINT STABILITY
 Articular surfaces
 Shape usually plays only minor role
 Some deep sockets or grooves do provide stability
 Ligaments
 Usually the more, the stronger the joint
 Can stretch only 6% beyond normal length before tear
 Once stretched, stay stretched
 Muscle tone
 Constant, low level of contractile force
 Keeps tension on the ligaments
 Especially important at shoulders, knees, arches of foot

22. MOVEMENTS ALLOWED BY SYNOVIAL
JOINTS
 Gliding
 Angular movements: or  the angle between two bones
DO TOGETHER
 Flexion
 Extension
 Abduction
 Adduction
 Circumduction
 Rotation
 Special movements

23.  Pronation
 Supination
 Dorsiflexion
 Plantar flexion
 Inversion
 Eversion
 Protraction
 Retraction
 Elevation
 Depression
 Opposition
SPECIAL MOVEMENTS

24. JOINT MOVEMENTS PICS
(FROM MARIEB, 4TH
ED.)

30. SYNOVIAL JOINTS
CLASSIFIED BY SHAPE
(OF THEIR ARTICULAR
SURFACES)
 Plane (see right)
 Hinge (see right)
 Pivot
 Condyloid
 Saddle
 Ball-and-socket

32. SHOULDER
(GLENOHUMERAL)
JOINT
 Stability sacrificed for mobility
 Ball and socket: head of
humerus with glenoid cavity of
scapula
 Glenoid labrum: rim of
fibrocartilage
 Thin, loose capsule
 Strongest ligament:
coracohumeral
 Muscle tendons help stability
 Disorders
Selected synovial joints
Rotator cuff muscles add to stability
Biceps tendon is intra-articular

33. ELBOW JOINT
 Hinge: allows only flexion and
extension
 Annular ligament of radius
attaches to capsule
 Capsule thickens into:
 Radial collateral ligament
 Ulnar collateral ligament
 Muscles cross joint
 Trauma

34. WRIST JOINT
TWO MAJOR JOINT SURFACES
SEVERAL LIGAMENTS
STABILIZE
1. Radiocarpal joint
 Between radius and
proximal carpals
(scaphoid and lunate)
 Condyloid joint
 Flexion extension
adduction, abduction,
circumduction
1. Intercarpal or midcarpal
joint
 Between the proximal and
distal rows of carpals

35. HIP (COXAL) JOINT
 Ball and socket
 Moves in all axes but
limited by ligaments and
deep socket
 Three ext. ligaments
“screw in” head of femur
when standing
 Iliofemoral
 Pubofemoral
 Ischiofemoral

36.  Acetabular labrum
diameter smaller than
head of femur
 Dislocations rare
 Ligament of head of femur
supplies artery
 Muscle tendons cross joint
 Hip fractures common in
elderly because of
osteoporosis

37. Right hip, AP view

38. KNEE JOINT
 Largest and most complex joint
 Primarily a hinge
 Compound and bicondyloid: femur and tibia both have 2 condyles
 Femoropatellar joint shares joint cavity
 At least a dozen bursae
 Prepatellar
 Suprapatellar

39.  Lateral and medial menisci
 “torn cartilage”
 Capsule absent anteriorly
 Capsular and extracapsular
ligaments
 Taut when knee extended to
prevent hyperextension

40.  Patellar ligament
 Continuation of quad
tendon
 Medial and lateral
retinacula
 Fibular and tibial
collateral ligaments
 Called medial and
lateral
 Extracapsular
 Oblique popliteal
 Arcuate popliteal

41. CRUCIATE LIGAMENTS
 Cross each other (cruciate
means cross)
 Anterior cruciate (ACL)
 Anterior intercondylar area of
tibia to medial side of lateral
condyl of femur
 Posterior cruciate
 Posterior intercondylar area of
tibia to lateral side of medial
condyl
 Restraining straps
 Lock the knee

42. CRUCIATE LIGAMENTS

43. KNEE INJURIES
 Flat tibial surface
predisposes to horizontal
injuries
 Lateral blow: multiple tears
 ACL injuries
 Stop and twist
 Commoner in women
athletes
 Heal poorly
 Require surgery

44. NKLE JOINT
 Hinge joint
 Distal tibia and fibula to talus
 Dorsiflexion and plantar flexion only
 Medial deltoid ligament
 Lateral ligaments: 3 bands
 Anterior talofibular
 Posterior talofibular
 Calcaneofibular
 Anterior and posterior tibiofibular
(syndesmosis)

45. RIGHT ANKLE, LATERAL VIEW

48. TEMPOROMANDIBULA
R JOINT (TMJ)
 Head of mandible articulates with
temporal bone
 Disc protects thin mandibular
fossa of temporal bone
 Many movements
Demonstrate movements together
 Disorders common

49. STERNOCLAVICULAR
JOINT
 Saddle joint
 Only other example is trapezium and
metacarpal 1 (thumb), allowing
opposion
 Sternum and 1st
costal (rib) cartilage
articulate with clavicle
 Very stable: clavicle usually breaks
before dislocation of joint
 Only bony attachment of axial skeleton
to pectoral girdle
Demonstrate movements together

50. DISORDERS OF JOINTS
 Injuries
 Sprains
 Dislocatios
 Torn cartilage
 Inflammatory and degenerative conditions
 Bursitis
 Tendinitis
 Arthritis
 Osteoarthritis (“DJD” – degenerative joint disease)
 Rheumatoid arthritis (one of many “autoimmune” arthritites)
 Gout (crystal arthropathy)