ligaments & joints lec 5

What is a ligament? (what does it do)

connect bone to bone

What are ligaments made out of?

dense regular connective tissue (NOT muscle tissue).

Why do ligaments take a long time to heal if torn?

no blood vessels of their own (unlike bones & muscles)

do have fibroblasts and collagen so they heal eventually

What is a tear in a ligament called?

sprain.

What is a tear in a muscle called?

strain

What will heal faster – a sprain or strain?

strain—better blood supply.

What are menisci and what type of tissue are they?

fibrocartilage pads in some joints (like the knee)

like a guide for joint movement to prevent unwanted movement

What are ligaments outside a joint capsule called?

extracapsular ligaments

e.g. Patellar ligament and Medial/Lateral collateral ligaments.

What are ligaments inside a joint capsule called?

intracapsular ligaments.

What structures are most important in keeping the knee from moving medially to laterally?

collateral ligaments

What is the difference between a

fibrous joint and a fibrocartilage joint?

FIBROUS JOINTS

• connected by fibrous connective tissue

• not cartilage

FIBROCARTILAGE JOINTS

• connected by fibrocartilage

• not connective tissue

Which fibrous joints are immovable (synarthrotic)?

Sutures and gomphosis

What movement classification are fibrous joints (Sutures and gomphosis)?

synarthrotic (immoveable)

Which fibrous joints are moveable?

Syndesmosis (ligament)

What movement classification are fibrous (Syndesmosis [ligament]) ?

It is amphiarthrotic (slightly moveable)

What type of tissue is found in a

syndesmosis?

Fibrous connective tissue

What type of joint classification

permits only slight degrees of

movement (partially movable)?

Amphiarthrotic

2 types of types of

CARTILAGINOUS JOINTS?

Fibrocartilage- amphiarthrotic ( a little movement)

Hyaline cartilage- synarthrotic (no movement)

2 examples of

fibrocartilage joints in the classification

of Cartilaginous Joints?

Vertebral discs amphiarthrotic ( a little

movement)

Pubic symphysis amphiarthrotic ( a little

movement)

2 examples of hyaline

cartilage joints, in the classification of

Cartilaginous Joints?

Epiphyseal plate,which is synarthrotic (no

movement)

Costal cartilage, which is synarthrotic (no

movement)

What joints are classified as having no

movement? (name the 3 joints)

Suture (between skull bones), gomphosis

(tooth socket), and synchondrosis (epiphyseal

plate)

What is the most common structure of

joint?

Synovial joints

How much can synovial joints move

ALOT

Where are synovial joints found

Almost every joint you think about is this

type (elbows, knees, hips, fingers)

What is the main thing that stabilizes

the hip joint?

The ligaments around the head of the femur

(not the little one on the fovea capitis)

What type of cartilage is at the ends

of long bones?

hyaline cartilage

What are the abbreviations for the

finger and toe joints?

MPJ:

• Metacarpal phalangeal joints

  • fingers

• metatarsal phalangeal joints

  • toes

IPJ: Interphalangeal joints

• knuckles of fingers and toes

• DIPJ: distal knuckles

• PIPJ: proximal knuckles

thumb (pollex) and big toe (hallux)

knuckle = IPJ

knuckles of the other digits = specifically DIPJ or PIPJ

What lines the inside of the joint

capsule/it’s function?

SYNOVIAL MEMBRANE makes SYNOVIAL FLUID

What are the 2 functions of

SYNOVIAL FLUID?

1. Lubricates joint

• allows smooth movement

  • viscosity changes with pressure (ooblek)

2. Nourishes articular cartilage (avascular)

• every movement puts pressure on joint,

forcing fluid into cartilage

• you need pressure on joints to feed cartilage

6 TYPES OF SYNOVIAL JOINTS

1. plane (gliding)

2. hinge

3. pivot

4. condyloid

5. saddle

6. ball and socket

What is a hinge joint?

sagittal plane.

elbow, knee, and interphalangeal (IPJ) joints (finger and toe joints).

What is a pivot joint?

one plane: transverse plane

only rotational movements

joint between the first two vertebrae

proximal radioulnar joint

• annular ligament on the ulna encircles the head of the radius

What is a condyloid joint?

two planes (biaxial

sagittal and frontal

Example: Metacarpal-phalangeal joints (MPJ’s)

What is a saddle joint?

two planes (biaxial)

sagittal and frontal

joint surface is both convex in one plane and concave

base of the thumb (between the trapezium and metacarpal I).

What is a ball and socket joint?

all three planes

shoulder and hip joints are ball and socket joints.