1. Articulations junction of 2 bones
MOTION OCCURS AT A JOINT -- NOT AT A LIMB
i.e. elbow flexion NOT forearm flexion
Articulations

2. Classification of joints
Synarthroses - fibrous joint with little or no movement
Amphiarthroses - cartilaginous joints with some motion
Diarthroses - (aka synovial) - freely movable joint
Articulations

4. Joint Classification based on number of axes of rotation
number of planes of motion
e.g. uniaxial -- 1 axis of rotation so 1 plane of motion
Articulations

5. Ball and Socket = Triaxial
e.g., flexion & extension
internal & external rotation
abduction & adduction
Condyloid = Biaxial
e.g., flexion & extension
internal & external rotation

6. e.g., flexion and extension
Pivot = uniaxial
e.g., supination
& pronation
Hinge = uniaxial
e.g., flexion and extension

7. Gliding = no axes Saddle = biaxial same as condyloid but greater ROM
‘gliding between
2 flat bones’
Saddle = biaxial
same as condyloid
but greater ROM
Ellipsoidal = biaxial
e.g., flexion & extension
abduction & adduction

8. Structure of Synovial Joint
A - articular (hyaline) cartilage (1-7 mm)
smooth elastic tissue on ends of bone
60-80% water
no blood supply
absorbs shock, distributes force and provides a low friction surface

9. Structure of Synovial Joint
B - fibrous capsule
very fibrous collagen tissue used to hold bones together
C - synovial membrane
lines the joint cavity
secretes synovial fluid to lubricate and provide nutrition
NOTE: B & C combine to form the articular capsule
or joint capsule

10. Structure of Synovial Joint
D - ligaments
connect bone-to-bone
usually restrict ROM at a joint
tendons (not shown)
connect muscle-to-bone
A* - Joint cavity

11. Other Structures of Synovial Joints
bursa
small capsules lined with synovial membranes
reduces friction between other structures in the joint
tendon sheaths
fascia surrounding tendon to reduce friction between tendon and surrounding structures
Olecranon bursa
Digital synovial sheath

12. Other Structures of Synovial Joints
articular fibrocartilage
different from articular cartilage
takes the form of a fibrocartilaginous disc or partial disc
distributes load over joint surface
improve fit of articulating surfaces
limit slipping of one bone relative to other
protect periphery of articulation
lubricate articulation
absorb shock

13. close-packed vs. loose packed
close packed position
maximum contact area
minimum mobility
maximum stability

14. Bony Stability (cont.)
amount of contact area

15. Joint Stability - Connective Tissue
ligamentous support

16. Properties of Connective Tissue
elasticity
ability to return to normal state after stretch
elastic limit
stretch beyond this limit will cause permanent damage
plasticity
stretched too far such that does not return to its normal state
ligament sprain (worse than bone fracture)
Articulations

17. deformation (length)
load
elastic
plastic
limit
Sprains occur in this region
Exercise
will help
increase
the loads
a ligament
or tendon
can sustain
Sprains result
in decrease of
joint stability

18. Joint Stability - Muscles
muscular arrangement
ability of muscle to provide support
muscle fatigue
cruciate rupture more likely when muscle is fatigued

19. Mobility
degree to which an articulation is allowed to move before being restricted by surrounding tissues
ROM a.k.a. flexibility
Articulations

20. Stability v. Mobility trade-off between stability and mobility
increase stability decrease mobility
vice-versa
Articulations

21. Neuromuscular Response to Stretching
Sensory neurons provide feedback on the characteristics of the muscle or other tissues.
2 neuromuscular proprioceptors:
MUSCLE SPINDLES &
GOLGI TENDON ORGANS

22. Muscle Spindles location: responds to: causes:
interspersed throughout muscle belly
responds to:
muscle length
muscle velocity
causes:
autogenic facilitation
reciprocal inhibition

23. Stretch Reflex
The muscle spindle is responsible for the stretch reflex.
As a muscle is rapidly stretched, the muscle spindle responds by facilitation of the same muscle and inhibition of the antagonistic muscle.
This reflex can be seen in the patellar tendon tap.

24. Golgi Tendon Organ location: responds to: causes:
near the muscle-tendon junction
responds to:
muscle tension
causes:
autogenic inhibition
antagonistic facilitation
Muscle Fibers
GTO
tendon

25. GOLGI TENDON ORGAN

26. “My Little GTO”
possibly the critical determinant to maximal lifting levels in weight training
may also be responsible for uncoordinated responses in untrained individuals
response is adapted through training
Articulations

27. STATIC BETTER THAN BALLISTIC
activate muscle
spindles which
elicits a stretch
reflex
if static position
achieved slowly then
can minimize muscle
spindle response
if held for sufficiently
long period (~30s) then
can elicit GTO
response
may result in
tearing a muscle
STATIC BETTER THAN BALLISTIC

28. ACTIVE STRETCH Spindle response: minimal if performed slowly
GTO response: active stretch of hip extensors
causes GTO to relax hip extensors and to
activate the hip flexors
motive force: actions of the hip flexors
consequences: no negatives -- limited ROM
limits possibility of injury and exercise
antagonists
ACTIVE
STRETCH

29. PASSIVE STRETCH Spindle response: minimal if performed slowly
GTO response: passive stretch of hip extensors
causes GTO to relax hip extensors
motive force: external force
consequences: no direct control of ROM thus
may exceed physiological limits and induce
muscle damage
PASSIVE
STRETCH

30. Stretching Proprioceptive Neuromuscular Facilitation PNF
alternating contraction - relaxation of agonist & antagonist muscles
takes advantage of the response of the proprioceptors
e.g. hamstrings
passive static stretch of hams - relax
active maximal concentric action of hams - relax
repeat

31. Plyometric Training
Plyometric training consists of exercises that rapidly stretch a muscle followed immediately by a contraction. They improve power output in the muscle by:
Neurological Influences: rapidly stretching of the muscle, which excites the motoneurons via the stretch reflex.
Structural Influences: involving elastic energy from the stretch-shortening cycle.

32. Source: Arthritis Foundation – www.arthritis.org
Refers to more than 100 different diseases that affect areas in or around joints.
The disease also can affect other parts of the body.
Arthritis causes pain, loss of movement and sometimes swelling.
Affects women more than men
Source: Arthritis Foundation –

33. Spondylarthropathies Source: Arthritis Foundation – www.arthritis.org
Osteoarthritis
20.7 million
Mostly after age 45
Rheumatoid
2.1 million
Mostly women
Fibromyalgia
3.7 million
Mostly women
Juvenile
Arthritis
285,000
Under age 17
Gout
2.1 million
Mostly men
Arthritis
Spondylarthropathies
412,000
Juvenile Rheumatoid
Arthritis (JRA)
50,000
Lupus
239,000
Source: Arthritis Foundation –

34. Source: Arthritis Foundation – www.arthritis.org
Osteoarthritis (OA), or degenerative joint disease, is one of the oldest and most common types of arthritis, characterized by the breakdown of the joint's cartilage. Cartilage is the part of the joint that cushions the ends of bones. Cartilage breakdown causes pain and joint swelling. With time, there will be limited joint movement.
Most commonly affects middle-aged and older people
Range from very mild to very severe
Affects hands and weight-bearing joints (e.g., knees, hips, feet and back).
OA is not an inevitable part of aging, although age is a risk factor
Obesity may lead to osteoarthritis of the knees
Joint injuries due to sports, work-related activity or accidents may be at increased risk of developing OA.
Source: Arthritis Foundation –

35. Source: Arthritis Foundation – www.arthritis.org
Rheumatoid Arthritis (RA) – a systemic disease that affects the entire body.
Characterized by the inflammation of the membrane lining the joint, which causes pain, warmth, redness and swelling.
The inflamed joint lining, the synovium, can invade and damage bone and cartilage.
Inflammatory cells release enzymes that may digest bone and cartilage.
The involved joint can lose its shape and alignment, resulting in pain and loss of movement.
The disease usually begins in middle age, but can start at any age, and affects two to three times more women than men.
Source: Arthritis Foundation –

36. Location of “Tender Points”
Fibromyalgia syndrome is a condition with generalized muscular pain and fatigue that is believed to affect approximately 3.7 million people.
The name fibromyalgia means pain in the muscles and the fibrous connective tissues (the ligaments and tendons). The condition is known as a syndrome because it is a set of signs and symptoms that occur together.
Fibromyalgia mainly affects muscles and their attachments to bones. Although it may feel like a joint disease, it is not a true form of arthritis and does not cause deformities of the joints. Fibromyalgia is, instead, a form of soft tissue or muscular rheumatism.
Source: Arthritis Foundation –

37. Arthritis Treatments Use of Heat or Cold Rest Medicines Exercise
(e.g., analgesics, NSAIDS,
DMARDS, Disease Modifying
Anti-Rheumatic Drugs)
Use of Heat or Cold
Helpful before and after exercise
Many respond better
to cold packs than to heat
Rest
More rest and less activity are needed during flares and the opposite is true during periods of improvement.
Exercise
(see next slide)
Surgery
joint replacement
Arthritis Treatments
Joint Protection
Careful use of joints to limit the pressure on the involved joint
Simple and inexpensive devices available
Diet
Lack of vitamins associated with progression of OA of the knee
Connection between obesity and OA of the knee
Diet high in Omega 3 fatty acids may help reduce inflammation in RA
In general, people with arthritis are urged to maintain a balanced diet and stay close to their ideal weight.
Physical/Occupational Therapy
recommend and teach prescribed muscle strengthening and range-of-motion exercises
teach non-medication ways to control pain
suggest ways to make everyday and work activities easier
Source: Arthritis Foundation –

38. Source: Arthritis Foundation – www.arthritis.org
Exercise
Proper exercises performed on a daily basis are an important part of arthritis treatment.
Exercise to help reduce weight can help prevent osteoarthritis in the knee.
Proper exercise helps build and preserve muscle strength, keep joints flexible and help protect joints from further damage.
Two categories of exercise:
Therapeutic -- Prescribed by a doctor, physical therapist or an occupational therapist. These exercises are based on individual needs and are designed to reach a certain goal.
Recreational -- Includes any forms of movement, amusement or relaxation that refreshes the body and mind. These exercises add to a therapeutic program, but do not replace it.
Three types of exercises:
Range-of-motion -- Moving a joint as far as it comfortably will go and then stretching it a little further. Range-of-motion exercises are designed to increase and maintain joint mobility that will decrease pain and improve function.
Strengthening -- Increases muscle strength to stabilize weak joints. These exercises use the muscle without moving the joint.
Endurance -- This type of exercise includes walking, swimming, bicycling, jogging, dancing and skiing. These dynamic forms of exercise increase endurance, whereas range-of-motion and strengthening do not. The most common risk in exercising is injury to joints and muscles. This usually happens from exercising too long or too hard, especially if a person has not been active for some time.
Source: Arthritis Foundation –