TEMPOROMANDIBULAR JOINT ANATOMY PATHOPHYSIOLOGY SURGERY

JOINTS- WHAT ARE THEY?  Osseous elements which are multiple that are joined by a variety of structural elements.  These co-aptations are grouped as arthroses

ARTHROSES  Concerned with differential growth, transmission of forces and with movement  FORCES  Tensile,compres sive,shear and torsion

TYPES OF ARTHROSES-2  1.SYNARTHROSES: which are solid non-synovial joints. Can be fibrous or cartilaginous.  Fibrous denotes intramembranous ossification  Cartilaginous denotes endochondral ossification

TYPES OF ARTHROSES-2  2. DIARTHROSES: which are cavitated synovial joints  Characterized by having articular surfaces covered by cartilage(hyaline or fibrocartilage) with its lubricated smooth wear resistant surface which glides over its fellow with minimal friction

SYNARTHROSES-TYPES  Sutures,synostoses  Gomphoses (peg and socket)  Synchondroses (manubriosternalis)

DIARTHROSES-TYPES  Can be simple(one pair of articulating, surfaces), compound(more than one pair of surfaces), or complex(with intracapsular meniscus or disc)  Surface shape:plane, spheroid(ball and socket), ellipsoid, ginglymus, bicondylar,trochoid(pivot) and sellar(saddle-shaped)

THE TMJ Are the only synovial joints with an articular disc

TMJ Classification  Anatomic Classification: Diarthrodial – two joints (joint spaces)  a joint that contains the following characteristics a freely movable joint bony surfaces are covered with hyaline or fibrocartilage lined by a synovial lining and contains synovial fluid

TMJ Classification  Functional classification: Ginglymo - arthroidial  Ginglymoid: rotation - inferior joint space  Arthroidial: translation - superior joint space

TMJ Classification  The mandible functions as a class III lever system Load - occlusal surface Fulcrum - TMJ Force - muscles of mastication

Anatomy Overview  Temporomandibular joint…  - the articulation of the mandibular condylar process with the glenoid fossa/articular eminence aspect of the temporal bone. Also includes the interposed articular disc and collateral ligamentous attachments.  -is an encapsulated, synovial joint.  -classified as a ginglymo-arthroidal joint due to its ability to function as a hinge as well as a gliding type of joint.  -functions as a Class III lever system.

QUESTION: ANATOMY What are the six (6) components of the temporomandibular joint articulation?

 Condyles  Articular surface of the temporal bone  Capsule  Articular disc  Ligaments  Lateral pterygoid

Osseous components

TOMOGRAPHC SCAN OF JOINT

SOFT TISSUE COMPONENTS  Muscles and ligaments  Disk  Posterior disk attachment  Joint capsule  Synovia

DISC POSITION

Anatomy Overview

TEMPOROMANDIBULAR DISORDERS  A collective term used to describe a number of related conditions that involve the TMJ’s, masticatory muscles, and associated structures; these conditions may present with facial pain, joint noises, limited jaw function, and other symptoms-ear ache, headache, tinnitus, neck/shoulder pain

HISTORICAL REVIEW  Costen syndrome 1934  Temporomandibular joint pain dysfunction syndrome 1955  Myofascial pain and dysfunction 1969  Facial arthromyalgia 1974  Temporomandibular disorders 1983  Craniomandibular disorders 1993

MOST COMMON TMDs  Myofascial pain and dysfunction  Internal derangement  Osteoarthrosis

MYOFASCIAL PAIN AND DYSFUNCTION  Refers to a group of poorly defined muscle disorders (eg, fibromyalgia) characterized by diffuse facial pain and episodic limited jaw opening  May result from parafunctional habits and significant relationship to psychophysiologic disorders such as stress or depression

INTERNAL DERANGEMENT  Abnormal relationship of the articular disc to the mandibular condyle, fossa,and articular eminence, interfering with the smooth action of the joint (Dolwick 1983)  Is a localized mechanical fault within the joint  Synonymous with disc displacement

WILKES CLASSIFICATION  STAGE I: TMJ clicking/no pain/no radiographic DJD  STAGE II: +Jt sounds/pain with intermittent locking but no x-ray DJD  STAGE III: As II, but with x-ray DJD  STAGE IV:ADD without reduction/DJD  STAGE V: Disc perf./Advanced DJD

OSTEOARTHROSIS  Is a nanpainful, localized degenerative joint disease that mainly affects bone and articular cartilage.  It is often idiopathic, but predisposing factors such as old age, repetitive trauma (bruxism), abnormal joint posturing, or multiple surgical procedures may be involved. If painful,then referred to as osteoarthritis

DEGENERATIVE CHANGES IN CONDYLE

EPIDEMIOLOGY  About 60-70% of the population have features of TMDs  About 20-30% report symptoms of TMDs  About 5% of people with TMD symptoms actually seek treatment  The female:male ranges from 3:1 to 9:1

TMJ SURGERY  Indicated for a subset of temporomandibular disorders: 1.Internal derangment; 2.Degenerative joint disease; 3. Rheumatoid arthritis; 4. Infectious arthritis; 5.Mandibular dislocation; 6.Ankylosis; 7.Condylar hyper/hypoplasia

CONTRALATERAL PAIN SUGGESTS ARTICULAR DISEASE

INTERNAL DERANGEMENT

SURGERIES OF THE JOINT  Discectomy  Disc repositioning  Condylotomy  Arthrocentesis  Arthroscopy  Partial and total joint replacement

HOLMLUND- HELMSING LINE

ARTHROSCOPY

ANKYLOSIS

TOTAL JOINT REPLACEMENT

PHYSICAL THERAPY