1. Anatomy and Physiology
Marieb’s Human
Anatomy and Physiology
Ninth Edition
Marieb w Hoehn
Chapter 8
Joints
Lecture 15
65 min, 38 slides

2. Lecture Overview Functions of joints Classification of joints
Types of joints
Types of joint movements
Some representative articulations

3. Functions of Joints (Articulations)
Form functional junctions between bones
Bind parts of skeletal system together
Make bone growth possible
Permit parts of the skeleton to change shape during childbirth
Enable body to move in response to skeletal muscle contraction
A “joint” joins two bones or, parts of bones, together, regardless of ability of the bones to move around the joint

4. Some Useful Word Roots Arthros – joint Syn – together (immovable)
Dia – through, apart (freely moveable)
Amphi – on both sides (slightly moveable)
Some Examples:
Synarthrosis – An immovable joint
Amphiarthrosis – A slightly movable joint
Diarthrosis – Freely movable joint
Functional Classification
(Very S-A-D)
Examples of synostoses: union of l/r mandible and frontal bones, cranial sutures in old age, epiphyseal lines.
What does the term ‘synostosis’ mean?

5. Classification of Joints
How are the bones held together? How does the joint move?
3 answers
3 answers
Structural
Functional
Fibrous Joints
dense connective tissues connect bones
between bones in close contact
synarthrotic
immovable
amphiarthrotic
slightly movable
diarthrotic
freely movable
Cartilaginous Joints
hyaline cartilage or fibrocartilage connect bones
Synovial Joints
most complex
allow free movement
have a cavity

6. Joint Classification Structural Classification of Joints Fibrous
Cartilaginous
Synovial (D)
Gomphosis (S)
Synchondrosis (S)
Gliding (N)
Suture (S)
Symphysis (A)
Hinge (M)
Pivot (M)
Syndesmosis (A)
Condyloid (B)
(S) = Synarthrosis (A) = Amphiarthrosis (D) = Diarthrosis
(N) = Nonaxial (M) = Monaxial (B) = Biaxial (P) = Polyaxial
Saddle (B)
Mnemonic for fibrous joints: “Go sue synde for telling a fib”
Mnemonic for cartilaginous joints: “Cartilage either synchs or swyms” (sinks or swims)
Mnemonic for types of synovial joints, in order from least movable to most movable: “Geeky Humans Play Competitive Saddle Ball”
Ball/Socket (P)
This would be a really good chart to know for the exam!

7. Fibrous Joints No synovial cavity (space between bones) fibrous CT
little or no movement
Figure from: Hole’s Human A&P, 12th edition, 2010
3 Types
Gomphosis
Suture
Syndesmosis
Syndesmosis (desmos = band or ligament; to bind)
long fibers connect bones
amphiarthrotic (slightly movable)
distal ends of tibia and fibula
radius and ulna
broad sheets or bundles
Mnemonic for types of fibrous joints: “Go sue synde for telling a fib”

8. Fibrous Joints Suture (sewing together) between flat bones
synarthrotic
thin layer of connective tissue connects bones
Gomphosis (bolting together)
cone-shaped bony process in a socket
tooth in jawbone
peg-in-socket
synarthrotic
Figure from: Hole’s Human A&P, 12th edition, 2010

9. Cartilaginous Joints No synovial cavity hyaline or fibrocartilage
little or no movement
Figure from: Hole’s Human A&P, 12th edition, 2010
2 Types
Synchondrosis
Symphysis
Synchondrosis
bands of hyaline cartilage unite bones
epiphyseal plate (temporary)
between manubrium and first rib (sternocostal)
synarthrotic (no movement)
A rib dislocation (slipping rib syndrome) or dislocation of a sternocostal joint is the displacement of a costal cartilage (ribs 2-7) from the sternum.
A rib separation refers to a dislocation of a costochondral junction between the rib and its costal cartilage.
Sternocostal joints
Mnemonic for cartilaginous joints: “Cartilage either synchs or syms” (sinks or swims)
Costochondral joints

10. Cartilaginous Joints Symphysis pad of fibrocartilage between bones
pubic symphysis (or symphysis pubis)
joint between bodies of vertebrae
amphiarthrotic
Figure from: Hole’s Human A&P, 12th edition, 2010

11. Synovial Joints * Diarthrotic (freely movable)
Structural features of diarthrotic joints
- joint cavity* - articular cartilage - synovial membrane - synovial fluid - reinforcing ligaments, bursae and tendons
- Articular cartilage in young, healthy joints is about 2 mm thick.
- Articular discs form in some joints and arise from the inner joint capsule. These are found in the temporomandibular, sternoclavicular, acromioclavicular, and distal radioulnar joints. - A meniscus (as in the knee joint) extends only partway across a joint with a gap between them, although functionally the menisci are the same as articular discs.
- Normal synovial fluid contains 3-4 mg/ml hyaluronan (hyaluronic acid), a polymer of disaccharides composed of D-glucuronic acid and D-N-acetylglucosamine joined by alternating beta-1,4 and beta-1,3 glycosidic bonds [2]. Hyaluronan is synthesized by the synovial membrane and secreted into the joint cavity to increase the viscosity and elasticity of articular cartilages and lubricate the surfaces between synovium and cartilage.[3]
Synovial fluid also contains lubricin secreted by synovial cells. It is chiefly responsible for so-called boundary-layer lubrication, which reduces friction between opposing surfaces of cartilage. There is also some evidence that it helps regulate synovial cell growth.[4]
Synovial fluid: Lubricates, distributes nutrients, and absorbs shock

12. Synovial Joints * Diarthrotic (freely movable)
Structural features of diarthrotic joints
- joint cavity* - articular cartilage - synovial membrane - synovial fluid - reinforcing ligaments, bursae and tendons
- Articular cartilage in young, healthy joints is about 2 mm thick.
- Articular discs form in some joints and arise from the inner joint capsule. These are found in the temporomandibular, sternoclavicular, acromioclavicular, and distal radioulnar joints. - A meniscus (as in the knee joint) extends only partway across a joint with a gap between them, although functionally the menisci are the same as articular discs.
- Normal synovial fluid contains 3-4 mg/ml hyaluronan (hyaluronic acid), a polymer of disaccharides composed of D-glucuronic acid and D-N-acetylglucosamine joined by alternating beta-1,4 and beta-1,3 glycosidic bonds [2]. Hyaluronan is synthesized by the synovial membrane and secreted into the joint cavity to increase the viscosity and elasticity of articular cartilages and lubricate the surfaces between synovium and cartilage.[3]
Synovial fluid also contains lubricin secreted by synovial cells. It is chiefly responsible for so-called boundary-layer lubrication, which reduces friction between opposing surfaces of cartilage. There is also some evidence that it helps regulate synovial cell growth.[4]
Figure from: Martini’s Visual A&P, 1st edition, 2011
Synovial fluid: Lubricates, distributes nutrients, and absorbs shock

13. Joint Classification Structural Classification of Joints Fibrous
Cartilaginous
Synovial (D)
Gomphosis (S)
Synchondrosis (S)
Gliding (N)
Suture (S)
Symphysis (A)
Hinge (M)
Pivot (M)
Syndesmosis (A)
Condyloid (B)
(S) = Synarthrosis (A) = Amphiarthrosis (D) = Diarthrosis
(N) = Nonaxial (M) = Monaxial (B) = Biaxial (P) = Polyaxial
Saddle (B)
Mnemonic for fibrous joints: “Go sue synde for telling a fib”
Mnemonic for cartilaginous joints: “Cartilage either synchs or swyms” (sinks or swims)
Mnemonic for types of synovial joints, in order from least movable to most movable: “Geeky Humans Play Competitive Saddle Ball”
Ball/Socket (P)
This would be a really good chart to know for the exam!

14. Types of Synovial Joints
Mnemonic for types of synovial joints (least movable to most movable): “Geeky Humans Play Competitive Saddle Ball”
Gliding (Plane) Joint
between carpals
between tarsals
between vertebrae
Hinge Joint
elbow
knee
between phalanges
Gliding joints – carpals, tarsals, articular processes of the vertebrae.
Hinge joints – elbow, knee, and interphalangeal joints.
Flat surfaces move past one another (nonaxial)
Angular open/close motion (monaxial)
Figure from: Hole’s Human A&P, 12th edition, 2010

15. Types of Synovial Joints
Pivot Joint
between proximal ends of radius and ulna
Saddle Joint
between carpal and metacarpal of thumb
sternoclavicular joint
Pivot joint: atlantoaxial and proximal radioulnar joints.
Saddle joint: trapeziometacarpal joint (allows for opposable thumb) and sternoclavicular joint.
Rotation around long axis (monaxial)
Angular motion (biaxial)
Figure from: Hole’s Human A&P, 12th edition, 2010

16. Types of Synovial Joints
Ball-and-Socket Joint
hip
shoulder
Condyloid Joint
between metacarpals and phalanges
between radius and carpals
Condyloid: radiocarpal and metacarpalphalangeal joints.
Movement around 3 axes and in between (multiaxial)
Angular motion (biaxial)
Figure from: Hole’s Human A&P, 12th edition, 2010

17. Movement of Synovial Joints
*All movements are based upon
The body being in anatomical position
All axial and appendicular joints being in full extension when in anatomical (zero) position
Important to define which joint you are examining before trying to define movement

18. Flexion and Extension Usually occur in the sagittal plane
Flexion – decrease in angle between bones and parts come together (usually in direction of greatest mobility)
Extension – increase in angle between bones and parts move further apart (usually after flexion)
Hyperextension – Extension beyond the anatomical position (limited by tendons/ligaments/bones)
Lateral Flexion – movement from side-to-side (in the frontal plane)

19. Flexion and Extension
Figure from: Martini, Anatomy & Physiology, Benjamin Cummings, 2004

20. ABduction, ADduction, and Circumduction
Usually occur in the frontal plane
ABduction – movement away from midline
ADduction – movement toward midline
Circumduction – Movement of the distal end of a limb in a circle

21. ABduction, ADduction, and Circumduction
Figure from: Martini, Anatomy & Physiology, Benjamin Cummings, 2004

22. Rotation, Pronation/Supination
Circumduction is actually a combination of flexion, abduction, extension, and adduction.
(Special movement – doesn’t fit into the other categories)
Bone revolves around its own longitudinal axis
Figures From: Marieb & Hoehn, Human Anatomy & Physiology, 9th ed., Pearson, 2013

23. Special Movements of Synovial Joints
Anterior/posterior movement in the transverse plane
Superior/inferior movement in the coronal plane
Figures From: Marieb & Hoehn, Human Anatomy & Physiology, 9th ed., Pearson, 2013

24. Special Movements of Synovial Joints
Figure from: Martini, Anatomy & Physiology, Benjamin Cummings, 2004

25. Joint Classification Structural Classification of Joints Fibrous
Cartilaginous
Synovial (D)
Gomphosis (S)
Synchondrosis (S)
Gliding (N)
Suture (S)
Symphysis (A)
Hinge (M)
Pivot (M)
Syndesmosis (A)
Condyloid (B)
(S) = Synarthrosis (A) = Amphiarthrosis (D) = Diarthrosis
(N) = Nonaxial (M) = Monaxial (B) = Biaxial (P) = Polyaxial
Saddle (B)
Mnemonic for fibrous joints: “Go sue synde for telling a fib”
Mnemonic for cartilaginous joints: “Cartilage either synchs or swyms” (sinks or swims)
Mnemonic for types of synovial joints, in order from least movable to most movable: “Geeky Humans Play Competitive Saddle Ball”
Ball/Socket (P)
This would be a really good chart to know for the exam!

26. Review

28. Shoulder (Glenohumeral) Joint
Figure from: Hole’s Human A&P, 12th edition, 2010
ball-and-socket
head of humerus
glenoid cavity of scapula
loose joint capsule
bursae
ligaments prevent displacement
very wide range of movement (but not as stable as hip)
Aka: humeroscapular joint

29. Shoulder Joint
Figure from: Hole’s Human A&P, 12th edition, 2010
Glenohumeral joint – greatest range of motion of any joint. Glenoid labrum is fibrocartilaginous. Most stability provided by muscles with the help of ligaments and tendons. Shoulder separation = partial or complete tearing of acromioclavicular joint.

30. Rotor Cuff *
Rotator cuff muscles = the SITS muscles * * *

31. Elbow Joint hinge joint (1) gliding joint (2) flexion and extension
Figure from: Hole’s Human A&P, 12th edition, 2010
hinge joint (1)
trochlea of humerus
trochlear notch of ulna
humeroulnar joint
gliding joint (2)
capitulum of humerus
head of radius
humeroradial joint
radioulnar joint (annular lig.)
flexion and extension
many reinforcing ligaments
stable joint
Largest and strongest articulation at elbow is the humeroulnar joint. Muscles that extend the elbow under control of radial nerve (in radial groove of humerus). Biceps brachii tendon attaches at radial tuberosity to supinate and flex the elbow. Upward twisting motion on arm when epiphyseal growth has not been completed, e.g., in children, may cause a partial dislocation called nursemaid’s elbow.
Which arm, and which view, are we looking at here?

32. Elbow Joint
Malgaigne's luxation - Partial dislocation of the head of the radius of the arm beneath the annular ligament of the radius. Also called nursemaid's elbow.
Figure from: Hole’s Human A&P, 12th edition, 2010

33. Hip (Coxal) Joint ball-and-socket joint head of femur acetabulum
Figure from: Hole’s Human A&P, 12th edition, 2010
ball-and-socket joint
head of femur
acetabulum
heavy joint capsule
many reinforcing ligaments
less freedom of movement than shoulder joint, but very strong
Hip joint = coxal joint. Fibrocartilage pad inside acetabulum; acetabular labrum = projecting rim of fibrocartilage that deepens acetabulum. Articular capsule is extremely dense and strong. Four ligaments stabilize the joint: iliofemoral, pubofemoral, ischiofemoral (these are thickenings of capsule), and the transverse acetabular ligament that crosses the acetabular notch. Ligament of femoral head originates at transverse acetabular ligament and attaches at fovea capitis.
Fovea capitis and ligamentum capitis (teres)

34. Hip Joint From: Saladin, Anatomy & Physiology, McGraw Hill, 2007
Figure from: Hole’s Human A&P, 12th edition, 2010
From: Saladin, Anatomy & Physiology, McGraw Hill, 2007

35. Knee (Tibiofemoral) Joint
Figure from: Hole’s Human A&P, 12th edition, 2010
largest, most complex joint
medial and lateral condyles of distal end of femur
medial and lateral condyles of proximal end of tibia
femur articulates anteriorly with patella (patellofemoral joint)
modified hinge joint
flexion/extension/little rotation
strengthened by many ligaments and tendons
menisci (fibrocartilage discs) separate femur and tibia
bursae
Permits flexion, extension, and limited rotation. Menisci are fibrocartilagenous pads. Patella is embedded in the tendon of the quadriceps superiorly and in the patellar ligament inferiorly. Popliteal ligaments reinforce knee’s posterior surface. ACL and PCL attach the intercondylar area of tibia to femoral condyles. Anterior and posterior refer to point of origin on tibia. ACL and PCL limit anterior and posterior movement of femur and maintain alignment of femoral and tibial condyles. Stabilizing tibial collateral and fibular collateral ligaments tighten only upon full extension of knee. (Tibial collateral ligament is firmly attached to the medial meniscus.)
At full extension, medial meniscus is jammed between the tibia and femur, locking the knee. Unlocking the knee requires contraction of the popliteus (medial rotation of tibia).

36. Knee Joint
retinaculae
Figure from Martini, Anatomy & Physiology, Prentice Hall, 2001

37. Knee Joint Deep posterior view, extended
From: Saladin, Anatomy & Physiology, McGraw Hill, 2007
(Meniscus = crescent)
Deep posterior view, extended
Figure from Martini, Anatomy & Physiology, Prentice Hall, 2001

38. Knee Joint Deep anterior view, flexed
Figure from Martini, Anatomy & Physiology, Prentice Hall, 2001

39. Life-Span Changes Joint stiffness is an early sign of aging
Regular exercise can prevent stiffness
Changes in symphysis joints of vertebral column diminish flexibility and decrease height
Synovial joints lose elasticity

40. Clinical Application – Joint Disorders
Sprains
damage to cartilage, ligaments, or tendons associated with joints
forceful twisting of joint
Bursitis
inflammation of a bursa
overuse of a joint
Arthritis
inflamed, swollen, painful joints
Rheumatoid Arthritis (RA)
Osteoarthritis (OA)
Gout

41. Rheumatoid Arthritis (RA)
Boutonniere’s deformity (swan neck).
Result of autoimmune attack on the joints
From: Saladin, Anatomy & Physiology, McGraw Hill, 2007

42. Joint Prostheses Prostheses used in knee replacement
Figures from: Saladin, Anatomy & Physiology, McGraw Hill, 2007
Be sure to check out the ExRx Articulations link on the Web site to get familiar with joint movements.

43. Review
Because the bones of the skeleton are rigid, movement can only occur at articulations (joints)
Joints can be classified by
Structure (newer style)
Function (older style)
A structural classification of joints includes:
Fibrous joints
Cartilaginous joints
Synovial joints

44. Review A functional classification of joints includes
Synarthroses (no movement)
Amphiarthroses (little movement)
Diartrhoses (free movement)
Important movements of joints to be familiar with
Flexion/Extension and Hyperextension
Abduction/Adduction and Circumduction
Supination/Pronation
Rotation
Dorsiflexion/Plantar flexion