1. The importance of synovial joint mobilization – scientific basis
(please click here)

2. The TMJ is a Synovial Joint
mobile
bones are separated by a joint cavity
synovial membrane lines the non-articular surfaces of the joint cavity
produces synovial fluid
THE TMJ FOLLOWS THE SAME BIOLOGICAL RULES AS ALL SYNOVIAL JOINTS

3. Joints Consist of Connective Tissue
cells
chondrocytes
osteocytes
fibroblasts
synovial cells
fibers
collagen
reticular
elastic
ground substance - glycosaminoglycans
sodium hyaluronate
chondroitin sulfate
keratan sulfate

4. Chondrocytes produce extracellular matrix
Collagen
Proteoglycans
viability of chondrocytes depends on synovial fluid

5. Articular Cartilage: Components
Proteoglycans: osmotically active
Collagen: provides structural support

6. Articular Cartilage Properties
Compressibility
Resiliency

7. Synovial Membrane Functions
synovial fluid production
lubrication
nutrition of chondrocytes
phagocytosis of substances in joint space

8. MOTION necessary for joint rehabilitation:
diffusion of nutrients from
synovial fluid
articular cartilage
nutrition of chondrocytes &
maintenance of cartilage matrix

9. Articular Cartilage Degradation
Excessive Joint Loading
Lack of Joint Motion

10. MOTION necessary to PREVENT ADHESIONS*
*Orthopaedic Research – 30 years
Akeson WH, et al. Clin Orthop 219:28, 1987
Salter RB. Clin Orthop 242:12, 1989
Ellis E, Carlson DS. Clin Plastic Surg 16(1):133, 1989

11. Hydrostatic-weeping Lubrication
COMPRESSION
DYNAMIC MOTION IN A JOINT CONTINUOUSLY PRODUCES A FLUID LAYER WHICH SEPARATES AND PROTECTS THE OPPOSING ARTICULAR SURFACES

12. Impaired Joint Lubrication
Damaged Joint Tissues
Impaired Joint Lubrication
boundary lubrication
hydrostatic-weeping lubrication
normal cartilage
cartilage degradation
synovial inflammation

13. IMMOBILIZATION EFFECTS JOINTS & SURROUNDING TISSUES
synovium
articular cartilage
muscles
ligaments
bone
periarticular connective tissue
Salter RB: Clin Orthop 242:12, 1989
Akeson WH, et al: Clin Orthop 219:28, 1987
Ellis E, Carlson DS: Clin Plastic Surg 16(1):133, 1989

14. EFFECTS OF IMMOBILIZATION ON SYNOVIUM:
obliteration of joint space
adhesions

15. EFFECTS OF IMMOBILIZATION ON CARTILAGE
cartilage has no blood supply
joint motion is necessary for the pumping action of synovial fluid movement is necessary for cartilage
nutrition
lubrication
repair

16. EFFECTS OF IMMOBILIZATION ON ARTICULAR CARTILAGE:
thinning
degeneration
erosion
impaired nutrition

17. EFFECTS OF IMMOBILIZATION ON MUSCLES:
atrophy
decreased muscle fiber diameter
decreased blood supply

18. EFFECTS OF IMMOBILIZATION ON BONE:
osteoporosis
invasion of subchondral bone by proliferating mesenchymal tissue

19. EFFECTS OF IMMOBILIZATION ON JOINT CONNECTIVE TISSUES (DISC, CARTILAGE, CAPSULE, LIGAMENTS)
reduced collagen mass
reduced matrix components
reduced water content
increased degradation compared to synthesis

20. SUMMARY EFFECTS OF IMMOBILIZATION ON SYNOVIAL JOINTS:
impaired joint homeostasis
impaired cartilage nutrition
articular cartilage degradation
intra-articular adhesions
atrophy of muscles
subchondral bone resorption
impaired lubrication