L29: Assessment and treatment of the TMJ Flashcards
What are 6 characteristics of TMJ disorders ?
- Affect 25-33% population, only a small percentage seek treatment
- Type of degenerative musculoskeletal disorder
- Can occur in association with headache or patients with TMJ problems may have co-existing cervical spine dysfunction
- 70% patients with TMJ disorders have malpositioning of the intraarticular disc “internal derangement”
- Effectively managed by medical, dental and physiotherapy practitioners
- Important to know when to refer to a dentist or specialist physio
What are 3 types of TMJ disorder?
- Primary TMJ disorder- chronic, traumatic
- TMJ pain associated with headache
- Headache with a TMJ component
- Myogenic dysfunction
- Arthogenic disorders
- Neurogenic disorder
What are the 5 functions of the TMJ?
- TMJ function is important for speech, mastication, swallowing, respiration etc.
- Having good TMJ function is important for survival
- One of the most utilized joints of the human articular system
- Highly specialised joint
- Part of a complex system
What are 6 characteristics of The Stomatognathic System?
- Bones: Skull, mandible, hyoid, clavicle and sternum
- Joints: Dentoalveolar, TMJs and assoc. ligaments and disc
- Muscles
- Vascular system
- Lymphatic system
- Teeth
- Innervated by the mandibular branch of the trigeminal nerve
- Intricate neurological controlling system
- **Close relationship to the Cervical spine**
What are 5 anatomical features of TMJ?
- Bilateral diarthrodial joint lined with fibrocartilage (Lined with hyaline cartilage?)
- 2 separate synovial cavities above and below disc
- Intra-articular fibrocartilaginous disc has posterior, intermediate and anterior bands
- Posteriorly disc is continuous with bilaminar retrodiscal pad
- Anteriorly it is attached to the lateral pterygoid
What is the articular disc in the TMJ? What are 2 parts of articular disc? What are 2 characteristics?
Disc continuous posteriorly with a bilaminar RETRODISCAL pad:
-
SUPERIOR portion – ELASTIC
- Allowing the mouth to open (stretch)
-
INFERIOR portion - NON-ELASTIC, provides restraint
- (Restraints so there sis a limit when opening mouth
- Vascular and richly innervated and potential source of pain
- Supported by Medial and lateral collateral ligaments – Provide proprioceptive feedback
- Restrict disc movement
What are the 2 other structures in the TMJ (apart from the articular disc)?
- A synovial membrane - lines each compartment
- A joint capsule
- Anteriorly fuses with the disc
- Posteriorly attached to the retrodiscal pad
- Reinforced laterally by the lateral TM ligament
What is the nerve supply at the TMJ?
- Trigeminal nerve (Cr V)
- Auriculotemporal nerve
- Cranial and cervical nerve supply
- Upper 3 cervical nerve roots
Can get _______ associated to TMJ due to nerve connections
headache
What are the 2 compartments of TMJ opening and closing?
- Inferior compartment
- allows rotation
- Superior compartment
- allows translation
What are the biomechanics of the TMJ?
Complex three dimensional combinations of rotational and translational motions
- ROTATION - med/lat, AP, longitudinal axes
- TRANSLATION - all directions
Occurs in superior joint compartment when disc/ (condyle) glides on the fossa and eminence
What are the 3 active movements of the TMJ?
- Elevation/depression (opening/ closing)
- Protraction (protrusion)/retraction
- Lateral displacement
What are the 4 accessory movements of the TMJ?
- Rotation
- Translation
- Distraction/compression
- Lateral glide
What are 3 phases of TMJ opening biomechanics?
Active opening (using muscles)
- Anterior rotation
- Anterior translation 15mm
- Small amount of anterior rotation
What are 2 phases of TMJ closing biomechanics?
- Movements reversed
- Disc pulled back by elastic fibres of retrodiscal pad
Passive recoil (unlike muscular active opening)
What are 3 phases of movements of TMJ?
- Rotation
- Inferior compartment
- 0-25mm opening
- Limited by horizontal fibres TM ligament
- Translation
- Superior compartment
- 25-40mm opening
- Limited by oblique fibres of TM ligament
- Rotation
- Inferior compartment
- 40+mm opening
- Limited by SM Ligaments (extra capsular)
What are 3 characteristics of phase 1 of movements of TMJ?
Rotation
- Inferior compartment
- 0-25mm opening
- Limited by horizontal fibres TM ligament
4.
What are 3 characteristics of phase 2 of movements of TMJ?
Translation
- Superior compartment
- 25-40mm opening
- Limited by oblique fibres of TM ligament
What are 3 characteristics of phase 3 of movements of TMJ?
Rotation
- Inferior compartment
- 40+mm opening
- Limited by SM Ligaments (extra capsular)
What are the 4 main muscles of the TMJ?
- Temporalis
- Masseter
- Lateral pterygoids
- Medial pterygoids
What are the muscle functions of temporalis of TMJ?
- All portions
- CLOSURE mouth/ELEVATION mandible
- Posterior portion
- RETRUSION and
- LATERAL DEVIATION (to same side)
What are the muscle functions of masseter of TMJ?
- All parts
- ELEVATION
- Superficial
- PROTRUSION
- Deep
- RETRACTION with ELEVATION
What are the 2 antagonistic parts of lateral ptergoid?
- SUPERIOR
- attaches to disc and condyle
- active in CLOSURE to POSITION or STABILISE the disc.
- INFERIOR
- acting bilaterally produces OPENING, PROTRUSION
- acting unilaterally produces LATERAL DEVIATION (to other side)
What are the 2 ways of medial ptergoid?
- acting bilaterally produces
- CLOSURE (particularly if in protrusion)
- PROTRUSION
- acting unilaterally
- LATERAL DEVIATION (to opposite side)
What are the 4 suprahyoid muscles? Where do the muscles go?
mandible to hyoid bone
What are the functions of Digastric and Geniohyoid?
mandibular depression and retrusion
What are the functions of Mylohyoid?
depression, tongue muscle
What are the functions of Stylohyoid?
swallowing - elevates and retracts hyoid
What are 4 muscles of the infrahyoid muscles? What are the functions?
- Sternohyoid
- Omohyoid (to scapula)
- Sternothyroid
- Thyrohyoid
- ANATGONISTS to SUPRAHYOIDS
- DEPRESS the hyoid, STABILISE
- Cervical Muscles
- STABILISATION in a neutral position