TMJ Flashcards
What kind of joint is the TMJ
Sliding Hinge Joint (ginglymoarthrodial joint)
What are the Articular surfaces associated with the TMJ?
Mandibular condyles and the mandibular fossa
Muscles of Mastication
Masseter, Temporalis, Lateral Pterygoid, and Medial Pterygoid
Masseter Movement
Elevate and protrusion
Temporalis Movement
Elevate and Retraction
Medial Pterygoid Movement
Elevate and retraction
Lateral Pterygoid Movement
Depress and protrusion
Muscles of mastication Innervation
Trigeminal Nerve (CNV), mandibular branch
TMJ Osteokinematics
Elevate (Close)
Depress (Open)
Protrusion
Lateral deviation
Depression Normal Values (How many mm is normal to open mouth?)
40-50 mm
Lateral Deviation Normal Values (How many mm is normal to open mouth?)
10 mm
Medial Deviation Normal Values (How many mm is normal to open mouth?)
10 mm
TMJ Arthrokinematics (Depression and Elevation)
- Roll in mandibular fossa first 20 mm
- Rotation (spin) - Slide onto articular eminence
- Translation
TMJ Arthrokinematics (Lateral Deviation)
- Ipsilateral rotation w/i fossa
- Contralateral transition
- anteromedial
TMJ Arthrokinematics (Protrusion)
- Forward slide w/o roll
- Translation only
Habits Effecting TMJ
- WB on mandibles
- Smoking
- Biting nails
- Chewing gum
- mouth breathing
- Snoring
- Mask Wearing
Objective TMJ Measures (Symmetry and Posture)
- Fascial Symmetry
- Posture
Breathing Pattern (Things to look for)
- Accessory muscles
- Mouth breathing
- Short upper lip (tendency to snore)
- Stridor
- Frenulum restriction (tongue tie)
Exterior Palpation
- Cervical Musculature
- Symmetries
- Hypertrophies
- Tenderness - Joint opening and Closing
- Symmetries
- Feel for any popping /clicking - Masseter Palpation
- Patient will clench and relax
Intra-Oral Palpation (Medial Pterygoid)
- Use index finger
- Slide along inside of bottom teeth all the way back to base of the tongue
- Have pt bite down gently
Intra-Oral Palpation (Lateral Pterygoid)
- Patient will open big
- slide back of pinky along outside of top teeth
- Have patient deviate ipsilateral and close slightly
Hypermobility Screen (Beighton)
- Do this BEFORE taking ROM measurements!
- Ask quick screening questions. ex)
- Can you bend over and place palms of hands on the floor? Can you bend your thumb back to touch forearm - Yes to 2 or more questions is 84% sensitivity and 87% specificity
TMJ Deviations
S- Curve
- lateral movements that return to midline
- Cause: neuromuscular dysfunction
TMJ Deflections
C- Curve
- Lateral movement that stays lateral when open
- Cause: muscle imbalance or capsular tightness
Intra-Oral Mobility Tests (Inferior Glide)
- Patient supine
- Therapist on Contralateral side
- Thumb on bottom molars and hand cradles mandible
- Distract caudally
Intra-Oral Mobility Tests (Anterior Glide)
- Patient supine
- Therapist on Contralateral side
- Thumb on bottom molars and hand cradles mandible (can try to hook back molar)
- Distract caudally first and then anteriorly
Intra-Oral Mobility Tests (Medial Glide)
- Patient supine
- Therapist on Contralateral side
- Thumb on bottom molars and hand cradles mandible
- Distract caudally then deviate towards therapist
Intra-Oral Mobility Tests (Lateral Glide)
- Patient supine
- Therapist on Contralateral side
- Thumb on bottom molars and hand cradles mandible
- Distract caudally then deviate away from therapist
TMJ Strength Testing
Grading:
* Functional – all available ROM and holds against resistance
* Weak functional – decreased motion and only able to hold minimal resistance
* Nonfunctional – no resistance tolerated
* 0 – no voluntary motion occurs
TMJ Other Testing
- Deep Cervical flexors
- Scapular Stabilizers
- Jaw Jerk reflex CNV
Common TMJ Pathologies
- Muscle Imbalance
- Disc Derangement
- Capsular fibrosis
- Inflammatory conditions
- Degenerative condition
Muscle Imbalance
A deflection (C- Curve) will occur towards tight side or away from lax side.
Disc Derangement w/ reduction
- 2 clicks (reciprocal)
- Mandible jumps on/off disc w/ depression/elevation
Disc Derangement w/o reduction
- Unable to open (limited by disc)
- patient will not be able to get past 40 mm of opening because disc does not go back in place
Capsular Fibrosis
- Usually w/ hx of long term disc dysfunction and or muscle imbalance
- usually no pains or joint sounds
- limited opening
- Deviation (S-curve) to ipsilateral side w/ depression and protrusion
- Lateral deviation limited to contralateral side
Inflammatory Conditions (Capsulitis)
- Pain w/ protrusion & deviation.
- Pain to bite on contralateral side
- pain to open wide
Inflammatory Conditions (Synovitis)
Degenerative Conditions
