Terminology

Question 1

1. Arthrology?
2. Joint (articulation or arthrosis)?
3. Kinesiology?
4. Arthrokinematics?
5. Osteokinematics?

Answer 1

1. Arthrology: the study of joints
2. Joint (articulation or arthrosis): a point of contact between two bones, between bone and cartilage and between bone and teeth.
3. Kinesiology: study of motion in the human body
4. Arthrokinematics: movements that occur inside the joint (roll, slide and spin)
5. Osteokinematics: movement of body parts (flexion, extension, adduction)

Question 2

1. Collagen fibres?
2. Cartilage?
3. Articular cartilage?
4. Articular capsule?
5. Ligaments?

Answer 2

1. Collagen fibres: main component of connective tissues, mostly found in fibrous tissues like cartilage, tendons, ligaments and skin.
2. Cartilage: flexible rubbery tissue made up of collagen and chondrocytes
3. Articular cartilage: smooth white tissue that covers the ends of bones where they form joints
4. Articular capsule: connective tissue surrounding a joint
5. Ligaments: bundles of collagen in parallel strips that connect one bone to another bone

Question 3

Joints – Articulations:

I. Definition?

II. Classified by?

Answer 3

I. Definition:

a. A point of contact between two bones, between bones and cartilage, or between bones and teeth.

b. Their surfaces allow for varying degrees of movement.

c. The joints of the skeletal system hold bones together and allow for movement and flexibility.

II. Classified by:

1. structure (how they look)
2. function (how much movement occurs)
3. biomechanical properties (how they move)

Question 4

Joint Classifications:

Structural Joints:

Answer 4

These joints are classified by structure or how they look.

Structural Joints:

a ) Fibrous

b) Cartilaginous

c) Synovial

Question 5

Joint Classifications:

Functional Joints:

Answer 5

These joints are classified by function or by how much movement occurs.

Functional Joints:

1. Synarthrosis: an immovable joint
2. Amphiarthrosis: a slightly movable joint
3. Diarthrosis: a freely movable joint (all synovial joints)

Question 6

Joint Classifications:

Biomechanical properties:

Answer 6

These joints are classified by function or by how the movement occurs.

Biomechanical properties:

1. Simple joint: two articulating surfaces, eg/ GH joint
2. Complex joint: two or more articulating surfaces with an articular disc or a meniscus,
   eg/ knee or TMJ
3. Compound joint: three or more articulating surfaces, eg/ radiocarpal joint

Question 7

Structural Joints:

Fibrous Joints:

Answer 7

Fibrous Joints:

These joints have no joint cavity. The articulating bones are held closely together by dense irregular connective tissue with lots of collagen fibres. This arrangement permits very little movement.

There are three types of fibrous joints:

1. Sutures
2. Syndesmosis
3. Interosseous membranes

Question 8

Structural Joints:
Fibrous Joints: Suture

Answer 8

Fibrous Joints:

Sutures

1. These joints occur between the bones of the skull.
2. They have irregular interlocking edges composed of a thin layer of dense irregular connective tissue.
3. They act as shock absorbers in the skull. They are immovable or a synarthrosis type of joint in adults.

**Slightly movable or amphiarthrosis in infants and children.

Question 9

Structural Joints:

Fibrous Joints: Synostosis

Answer 9

Fibrous Joints:

Synostosis:

1. This is a type of suture joint that is replaced by bone as an adult.
2. In this joint there is a complete fusion of two separate bones into one.
3. Synostosis joints are classified as synarthrosis joints as they are immovable because they have ossified.

eg/ frontal bone

Question 10

Fibrous Joints:

Syndesmosis:

Answer 10

Fibrous Joints:

Syndesmosis:

1. This joint has a band or a ligament, made of dense irregular connective tissue arranged in a bundle.
2. The two joint surfaces are further away from each other.
3. This permits slight movement or a amphiarthrosis type of joint.

eg/ tibiofibular joint: distal tibiofibular ligament connects the tibia and fibula.

eg/ teeth-gomphosis joint: periodontal ligament connects the tooth to the socket, permits no movement synarthrosis.

Question 11

Structural Joints:

Interosseous Membranes:

Answer 11

Fibrous Joints:

Interosseous Membranes:

1. A substantial sheet of dense irregular connective tissue that binds neighbouring long bones and permits a small amount of movement so a amphiarthrosis type of joint.

Two in the body:

between the radius & ulna
between the tibia & fibula

Question 12

Structural Joints:

Cartilaginous Joints:

Answer 12

Cartilaginous Joints:

a. have no synovial cavity and allow for little to no movement.

b. The articulating bones are tightly connected by either hyaline cartilage or fibrocartilage.

There are three types:

1. Synchondrosis
2. Symphysis
3. Epiphyseal cartilage

Question 13

Structural Joints:

Cartilaginous Joints:

Synchondrosis

Answer 13

Cartilaginous Joints:

Synchondrosis:

1. The connecting material in this joint is hyaline cartilage and this joint is slightly movable or amphiarthrosis to immovable or synarthrosis.
2. This joint ossifies in adulthood and becomes a synostosis or bony joint.

Eg/ first rib & the manubrium of the sternum

Question 14

Structural Joints:

Cartilaginous Joints:

Symphysis

Answer 14

Cartilaginous Joints:

Symphysis:

1. The connecting tissue is also hyaline cartilage but also has a broad, flat fibrocartilaginous disc that connects the bones.
2. All symphysis joints occur in the midline of the body and are slightly moveable or a amphiarthrosis type of joint.

Eg/ intervertebral discs, pubic symphysis

Question 15

Structural Joints:

Cartilaginous Joints:

Symphysis

Answer 15

Cartilaginous Joints:

Symphysis:

All symphysis joints occur in the midline of the body and are slightly moveable or a amphiarthrosis type of joint.

Question 16

Structural Joints:

Cartilaginous Joints:

Epiphyseal Cartilage

Answer 16

Cartilaginous Joints:

Epiphyseal Cartilage:

1. The epiphyseal cartilage is not a joint but a growth centre within the bone.
2. They are covered with hyaline cartilage.
3. This joint is not about movement but about growth within the bone.
4. No movement occurs at this joint so it is considered a synarthrosis type of joint.
5. Once bone elongation growth has stopped
   after puberty, the epiphyseal plate closes and
   the joint is now considered a synostosis
   type of joint.

Question 17

Structural Joints:

Synovial Joints:

Answer 17

Synovial Joints:

1. These joints have a fluid filled cavity called the synovial cavity between the articulating bones. The fluid is called synovial fluid.
2. The cavity is covered by a capsule. This capsule is made of dense irregular connective tissue.
3. The bones at the ends of the joint are covered by a layer of hyaline cartilage that is smooth and slippery called articular cartilage. Articular cartilage reduces friction between bones and absorbs shock.
4. This capsule filled with fluid type of joint allows for many different types of movement as well as lots of movement in general. Synovial joints are classified as a diarthrosis type of joint.

Question 18

Synovial Joint:

Articular Capsule:

Answer 18

Articular Capsule:

1. The articular capsule covers the entire synovial joint and encloses the synovial cavity while uniting the articulating bones.
2. The articular capsule or joint capsule separates the inside of the joint from the outside of the joint and has two membranes:

a. Fibrous Membrane: dense irregular connective tissue-mostly collagen, connects to the periosteum of the articulating bones

b. Synovial Membrane: areolar connective tissue with elastic fibres, synoviocytes produce synovial fluid that contains hyaluronic acid

Question 19

Synovial Joint:

Synovial Fluid Functions:

Answer 19

Synovial Fluid Functions:

1. lubricates the synovial cavity
2. reduces friction
3. shock absorbers
4. supplies oxygen and nutrients
5. takes away wastes like carbon dioxide
6. contains phagocytes to remove normal debris
   or microbes from wear and tear

If a joint is inactive the synovial fluid becomes thicker and less viscous, which is one main reason to warm up before activity, this stimulates the production and secretion of more synovial fluid, which means less stress on the joints.

Question 20

Synovial Joint:

Accessory Ligaments:

Answer 20

Accessory Ligaments:

1. Extracapsular ligaments: outside the capsule
2. Intracapsular ligaments: inside the capsule

eg/ knee
Intracapsular ligaments: ACL, PCL
Extracapsular ligaments: lateral & medial collateral ligaments

Question 21

Synovial Joints:

Articular Discs:

Answer 21

Articular Discs:

1. Articular discs occur inside some synovial joints.

2.They can be a crescent shaped pad of fibrocartilage that lies between the articulating bones.

3. These discs may be called a meniscus or menisci (as in the knee) or articular discs.
4. These discs act as shock absorbers.
5. They also make a better fit between the articulating bones.
6. They distribute the weight and the synovial fluid over a greater surface area.
7. The disc also binds strongly to the inside of the fibrous membrane and often subdivides the synovial cavity into two separate spaces, allowing separate movements, like in the TMJ joint.

Question 22

Synovial Joints;

Labrum:

Answer 22

Labrum:

1. The labrum is a fibrocartilaginous lip that extends from the edge of a joint socket.
2. It helps deepen the socket and increases the surface area of contact between the ball and the socket.
3. Occurs in ball and socket joints of the hip and shoulder.

Question 23

Tendon Sheaths around Synovial Joints:

Tendon Sheaths:

Answer 23

Tendon Sheaths:

1. The covering over the tendon that reduces friction at joints.
2. It is a tube-like bursa that wraps around some tendons especially around the wrists and ankles.
3. It contains a small amount of synovial fluid.
4. It reduces friction in the common back and forthing in many repetitive activities.

eg/ transverse humeral ligament over biceps

The transverse humeral ligament that holds the biceps tendon in has a tendon sheath around it for protection and friction reduction

Question 24

Synovial Joints:

Bursae:

Answer 24

Bursae:

1. A bursa is a fluid filled sac lined with a synovial membrane that acts as a cushion or protection around a joint by reducing friction.
2. It may be located between skin and bones, between tendon and bones, between muscles and bones or between ligaments and bones.
3. These are all locations where rubbing or friction occurs.
4. Bursitis: inflammation of a bursa around a joint

Question 25

Synovial Joint Types

Answer 25

There are six types of synovial joints:

1. Plane (planar) Joints:

a. These joints have flat or slightly curved surfaces that permit back and forth or gliding and side to side movements.

b. The articular capsule around these joints limits their movements. These joints can be biaxial or triaxial.

eg/ acromioclavicular and sternoclavicular

2. Hinge (ginglymus):

a. This joint contains a convex surface of one bone articulating into the concave surface of another bone.

b. This configuration permits only one type of movement in one plane, flexion and extension, so it is called uniaxial.

c. This movement is an opening and closing motion like a door.

eg/ elbow, knee

3. Pivot (trochoid):

a. The articulating surfaces of a pivot joint is a rounded or pointed surface of one bone articulating with a ring formed by another bone and a ligament.

b. This configuration allows for rotation only around a single axis therefore a uniaxial joint.

eg/ atlantoaxial joint, radioulnar joint

4. Condyloid (ellipsoid):

a. This joint has a convex oval shaped projection of one bone that fits into the oval shaped depression of another bone.

b. It has two degrees of motion so is considered a biaxial joint (flexion/extension, abduction/adduction, circumduction).

eg/ radiocarpal joint

5. Saddle (sellar):

a. The saddle joint has an articular surface of one bone that is saddle shaped and the articular surface of the other bone fits in the saddle like a rider would sit in a saddle.

b. This configuration allows for two planes of motion, a biaxial joint (flexion / extension, abduction / adduction, circumduction)

eg/ carpometacarpal joint (trapezium and the thumb)

6. Ball and socket (spheroid):

a. This joint has a ball shaped surface of one bone fitting into a cuplike depression of another bone.

b. This configuration allows for the joint to move in many directions therefore it is a triaxial or multiaxial type of joint.

c. Allowing for flexion/extension and abduction/adduction and rotation.

Glenohumeral Joint (shoulder)
Iliofemoral Joint (hip)

Question 26

Synovial Joints:

Factors affecting contact in a synovial joint:

Answer 26

Factors affecting contact in a synovial joint:

1. Structure or shape of articulating bones, how closely they can fit together
2. Strength and tension or tautness of the ligaments around the joint, in certain positions moreso, restrict some ranges of motion and also direct the movement at the joint
3. Arrangement and tension of the muscles, flexed hip restricted by hamstrings
4. Contact of soft parts, this may limit mobility
5. Hormones: relaxin produced at or near birth increases the flexibility of fibrocartilage in the pubic symphysis joint to expand the pelvic outlet for delivery
6. Disuse: restricts movement, decreases synovial fluid, muscles atrophy, joint becomes less and less mobile and flexible

Question 27

Synovial Joint Movement:

Answer 27

Synovial Joint Movement:

1. Uniaxial: movement in one plane, around one axis (elbow)
2. Biaxial: movement in two planes, around two axes (metacarpophalangeal joint)
3. Triaxial or multiaxial: movement in all three planes, around all three axes (shoulder)

Question 28

Synovial Joints:

Joint surfaces move:

Answer 28

Joint surfaces move on one another and are described in three general ways.

1. Roll: one bone rolls on another:

This is a motion where one articular surface rolls on another.

eg/ the femur rolls on the tibia

2. Spin: one bone spins on another:

This is a motion where one bone moves but the axis remains stationary.

eg/ the femur spins on the tibia

3. Slide: one bone slides (glides) on another:

This is a motion where one articular surface slides on another.

eg/ the femur slides on the tibia

Question 29

Nerve Supply to Synovial Joints:

Answer 29

Nerve Supply to Synovial Joints:

1. The same nerves that innervate the skeletal muscles that move the joint also innervate the joint itself.
2. Synovial joints contain many nerve endings that are distributed throughout the articular capsule and close by ligaments.
3. Some sensory nerve endings convey information about pain from the joint to the spinal cord and into the brain for processing, while other sensory nerve endings respond to the degree of movement and stretch at a joint.
4. The spinal cord and brain respond by sending impulses through different nerves (motor nerves) to the muscles to adjust body movements.

Question 30

Synovial Joints:

Blood Supply:

Answer 30

Blood Supply:

1. The articular cartilage of a synovial joint is avascular and the fibrous capsule and ligaments have a poor blood supply.
2. However the synovial membrane is highly vascularized with blood capillaries.
3. Many arteries in the vicinity send out numerous branches that penetrate the ligaments and articular capsule to deliver oxygen and nutrients to the inside of the joint.
4. Veins remove carbon dioxide and wastes from the joint.
5. The arterial branches from several different arteries typically merge around a joint before penetrating the articular capsule.
6. Chondrocytes in the articular cartilage of a synovial joint receive oxygen and nutrients from synovial fluid derived from blood; all other joint tissues are supplied directly by capillaries.
7. Carbon dioxide and wastes pass from chondrocytes of articular cartilage into synovial fluid and then into veins; carbon dioxide and wastes from all other joint structures pass directly into veins.

Question 31

Synovial Joints;

Types of Movement:

Answer 31

Four main types of movement:

1. Gliding:

Gliding is a simple movement where nearly flat bone surfaces move back and forth or side to side on one another.

This type of movement is limited due to capsules, ligaments and bone shapes.

eg/ intercarpals & intertarsals

2. Angular movements:

Angular types of movements change the angle between the two articulating bones.

Lateral Flexion: Trunk and Head

Hyperextension:

This type of motion is found in hinge joints like the elbow, interphalangeal and knee joints.

The motion is prevented by ligaments and bone alignment.

Abduction: movement of bone away from midline

Adduction: movement of bone toward the midline

Circumduction:

This is movement at the distal end of a body part in a circle.
It is a combination of flexion, abduction, extension, adduction and rotation all at the same time. A circular movement.

3. Rotation:

This is a circular motion in one axis.

4. Special movements:

a. Elevation: This is a superior motion, raising up

b. Depression: This is an inferior motion, pressing down.

c. Protraction: This movement is to draw outwards

d. Retraction: This movement is to draw inwards

e. Inversion: This movement turns inward or medially.

f. Eversion: This movement turns outward or laterally.

h. Dorsiflexion: This movement is towards the dorsal side of the foot or the superior surface.
“standing on your heels”

g. Plantarflexion: This movement is towards the plantar side of the foot or the inferior surface.
“standing on your toes”

k. Radial Deviation: Abduction of the wrist away from midline

l. Ulnar Deviation: Adduction of the wrist towards the midline

m. Supination (fore arm): This movement is where the palm is turned anteriorly or upward. Think of the anatomical position.

n. Pronation (fore arm) :This movement is where the palm is turned posteriorly or downward.

o. Supination: This movement is where the foot is turned inward.

p. Pronation: This movement is where the foot is turned outward.

q. Opposition: This is the movement of the thumb across the hand to touch the fingertips. It is a combination of flexion, adduction and internal rotation.

Question 32

Range of Motion

Answer 32

1. Range of motion is a measurement of the amount of movement around a specific joint.
2. We use a goniometer to measure ranges of motion in the human body in degrees.
3. It measures the amount of movement allowed by the shape of the joint and by the surrounding soft tissues.
4. It may show the joint’s movement is limited, normal or excessive.
5. For a joint to have use of its full range of motion it must also have good flexibility.
6. The flexibility is measured in degrees and measures the joints range of motion.
7. This measurement could result from ligaments, tendons, muscles, bones or joints affecting it.

Question 33

We have 2 common ways to measure range of motion:

Answer 33

We have 2 common ways to measure range of motion:

1. Passive (or relaxed): the therapist makes the motions of the joint while the patient is relaxed through the unrestricted range, the patient does not contract muscles. The anatomic barrier is the end of the passive range of motion.
2. Active: the patient “actively” contracts the voluntary muscles crossing the joint, moving the joint through its range of motion. The physiologic barrier is the end of the active range of motion.

Question 34

Closed Packed Position:

Answer 34

1. This is a joint position in which the articulating bones have their maximum area of contact with each other and it is called maximum congruency.
2. The joint capsule becomes twisted causing the joint surfaces to become fully approximated and no further movement is possible.
   It is in this position that joint stability is the greatest.
3. Each synovial joint has a point in its range of motion where its surfaces are maximally congruent, its capsule and ligaments are maximally taut and elongated and its surfaces are maximally compressed.
4. Injury in the closed packed position will most likely result in fracture and/or dislocation

Question 35

Open Packed (Loose) Position
Resting Position:

Answer 35

1. This is a position of the joint where the joint surfaces become separated and have little congruity and minimal joint surface contact.
2. The joint capsule is relaxed and untwisted as well as the major ligaments.
3. The joint is under the least amount of stress in this position, which is why we do most joint mobilizations in the resting position.
4. The joint has minimal stability in this position.
5. Most sprains and strains occur in the open packed or loose position.
6. When swelling occurs the joint assumes the open packed position.

Question 36

Capsular Pattern of Restriction:

Answer 36

1. The capsular pattern of restriction is a predictable pattern of movement restriction that occurs in a synovial joint when the entire joint capsule is injured or affected.
2. It is a result of a total joint reaction. Only joints controlled by muscles have a capsular pattern.
3. The pattern names the most restricted range of motion to the least restricted range of motion.
4. When testing range of motions in a specific joint, one would find a predictable pattern of limitation to specific joint movements that can be measured and retested.

Example: Shoulder or GH joint:

Capsular pattern of restriction:
lateral rotation>abduction>medial rotation

This means that lateral rotation and abduction are the first restricted movements you will find and medial rotation is the last to be restricted.

Question 37

Joint Sensors

Answer 37

Proprioception:

This is a type of sensation that tells our brain where our body is in space.

Kinesthesia is the perception of body movements.

Sensory information travels to the brain relaying information about what our joints are doing,
where our head and limbs are, how they are moving etc. and our brain
responds.

This sensory information is picked up by specialized receptors called proprioceptors that are embedded in our muscles and tendons especially surrounding our joints.

They are abundant around our spine for posture.

They decide how much a muscle contracts, the amount of tension in a tendon, the position of a joint or weight discrimination (how heavy is that box?).

The brain continually receives input related to the body’s position and makes adjustments to ensure coordination.

Question 38

Joint Sensors:

3 types of proprioceptors:

Answer 38

3 types of proprioceptors in and around joints:

Muscle spindles: within skeletal muscles

Tendon organs: within tendons

Joint kinesthetic receptors: within the synovial joint capsule

Question 39

Joint Sensors:

Proprioceptors:

Muscle Spindle:

Answer 39

Muscle Spindle:

These sensors monitor changes in the length of a skeletal muscle.

The small degree of contraction that is present at all times and while the muscle is at rest is called muscle tone and is due to the muscle spindles.

Each muscle spindle consists of slowly adapting sensory nerve endings that wrap around 3 to 10 specialized muscle fibers, called intrafusal muscle fibres.

A connective tissue capsule encloses the sensory nerve endings and intrafusal fibers and anchors the muscle spindle to the endomysium and perimysium.

Extrafusal fibres are regular muscle fibres that surround the muscle spindle.

Muscle spindles are interspersed among most skeletal muscle fibers and are aligned parallel to the fibres.

1. Finely controlled or precise movements: fingers and eye movements muscle spindles are plentiful

activity: reading music and playing an instrument

2. Coarser but more forceful movements: thigh muscles, muscle spindles are fewer

activity: forceful deadlifts using quadriceps femoris and hamstring muscles of the thigh

The only skeletal muscles that lack muscle spindles are the tiny muscles of the middle ear.

Question 40

Joint Sensors:

Proprioceptors:

Golgi Tendon Organs:

Answer 40

Golgi Tendon Organs:

These sensors are located at the junction of a tendon and a muscle or the musculotendinous junction.

Golgi tendon organs protect tendons and their associated muscles from damage due to excessive tension by initiating tendon reflexes.

When a muscle contracts, it exerts a force that pulls the points of attachment of the muscle at the musculotendinous junction at either end towards each other, this force is the tension.

Each tendon organ consists of a thin capsule of connective tissue that encloses a few tendon fascicles (bundles of collagen fibers).

Penetrating the capsule are one or more sensory nerve endings that entwine among and around the collagen fibers of the tendon.

When tension is applied to a muscle, the tendon organs generate nerve impulses that propagate into the brain, providing information about changes in muscle tension.

The resulting tendon reflexes decrease muscle tension by causing muscle relaxation.

Question 41

Joint Sensors:

Proprioceptors:

Joint Kinesthetic Receptors:

Answer 41

Joint Kinesthetic Receptors:

Monitor stretch in a synovial joint and send information to the brain for a response.

Joint kinesthetic receptors: present within and around the articular capsules of synovial joints

Free nerve endings: in the joint’s connective tissues
Ruffini corpuscles: in tendons: in the joint capsule, are slow adapting, respond to pressure

Small Pacinian corpuscles: in skin and tendons, are fast adapting, in the connective tissues outside articular capsules, respond to acceleration and deceleration of joints during movement.

Joint ligaments contain receptors similar to tendon organs that adjust reflex inhibition of the adjacent muscles when excessive strain is placed on the joint

Question 42

Common Joint Disorders:

Arthropathies:

Answer 42

1. Sprain: stretching or tearing of a ligament,
2. Dislocation: joint alignment is interrupted
   Subluxation: partial or incomplete dislocation of a joint
3. Bursitis: inflammation of a bursa around a joint,
4. Tendinitis: inflammation of a tendon and/or tendon sheath (tenosynovitis)
5. Arthritis: inflammation of a joint, caused by age related degeneration, past trauma, inflammatory or autoimmune diseases or metabolic diseases like gout.

Question 43

Effects of Aging on joints:

Answer 43

Effects of Aging on joints:

Decreased production of synovial fluid

Decreased joint space

Articular cartilage becomes thinner

Ligaments shorten and lose some of their flexibility

Muscles weaken and weaken joints

These effects on joints are influenced by genetic factors and by wear and tear, and they vary considerably from one person to another.

Degenerative changes in joints may begin as early as age 20, most changes do not occur until much later.

At age 80, most everyone develops some type of degeneration in the knees, elbows, hips and shoulders.

The hips, knees and lumbar spine are often the first joints affected. These are all weight bearing joints.

.

Question 44

Joint Replacements:

Arthroplasty:

Answer 44

When the degeneration is severe and weight bearing is too painful, the joint may be replaced with artificial joints.

This surgery is called arthroplasty.

Hips and knees are common joint replacements in the elderly.

The surgery entails removing the ends of the bones that are severely damaged and replacing them with a metal, ceramic or a plastic component.