TMJ sx Flashcards
McCain
What two pieces of information are needed to treat TMJ disorders?
Etiology of Disorder and Classifcation of disorder
What are 5 etiologies of TMD?
- Parafunction
- Dentofacial deformities/malocclusions
- Direct macrotrauma to jaw
- Indirect macrotrauma to jaw (acceleration/deceleration injury that caused rapid jaw movement)
- Systemic disease
Synovial joint disease of the TMJ can be broken down to two categories? what are they and their sub categories?
Inflammatory and Non inflammatory
Inflammatory can be broken down to primary and secondary arthritis.
Primary arthritis is immune based (RA, JA)
Secondary Arthritis is reactive (trauma, infection)
noninflammatory = internal derangement, OA)
Crepitation of the joint indicates?
Perforation of the disc
What is normal MIO?
35-55mm
What is the McCain sign/test? (joint loading)
take two tongue blades and have bite on cuspids, right and left side.
If patient has pain it is joint pain (not muscular).
biting causes condyle to compress retrodiscal tissue, which if inflamed will have pain.
Minimal pain if already perforated
Preoperative if is important to do what examination?
Otoscopic exam -eval for wax and tympanic membrane issues (pull ear up and back)
How is a panoramic useful in TMJ problems?
can evaluate teeth relationships and bony relationship
What is first line of tx for TMJ disorders?
Conservative treatment
- soft diet/rest
- NSAIDs
- Muscle relaxants (Baclofen = peripheral acting) (Flexeril/cycloebenzaprine = central acting)
- tx parafunctional habits (biteguard/occlusal splint)- ALL PTS get a SPLINT except those with minimal opening
- consider PT
- consider occlusion
Are COX-1 or COX-2 enzymes more likely to cause inflammation? What inhibits this enzyme?
COX-2
Celebrex, Mobic (low dose)
When would you get serology testing for TMJ pts?
Condylar resorption
Rheumatoid factor, ANA, CCP, HLa-B27, Vit. D, 17B estradiol should be tested
How do occlusal splints work?
positions teeth so condyle doesn’t rest on retrodiscal tissue. This decreases inflammation and allows disc to reduce.
MRI; T1 vs t2 whats the difference?
T1 = water is black - shows anatomy, disc, position of disc, and morphology
T2 = water is white - shows joint effusions
What is an internal derangement?
localized mechanical faults in a synovial joint that interferes with smooth action
Define Wilkes I
Wilkes I = Click with no pain, minimal displacement and morphologic changes
Define Wilkes II
Wilkes II = Click with Pain, with minimal positional changes ( ADD) and minimal morphologic changes
Define Wilkes III
Wilkes III = Click ( maybe in past) with pain. Closed lock and limited range of motion.
Morphologic and positional changes noted - chronic ADD and adhesion formation
Define Wilkes IV
Wilkes IV = No click - Chronic, episodic pain with bony changes and ADD
Define Wilkes V
Wilkes V = crepitus limited ROM, likely with perforation and bony changes
What are numbers needed to know for arthrocentesis?
along holmlund-Hellsing line horizontal (tragus to eye canthus)
10 mm anterior to mid tragus and 2mm below line = entrance point to glenoid fossa
-Insufflation with 3-5 mL
20 mm anterior to mid tragus and 10mm inferior to line is the site of eminence
Center of superior joint space is 25mm deep
Requires 200-200 mm of fluid irrigation
Level I Arthroscopy is defined as?
Diagnostic single puncture arthroscopy!
What is the pertinent anatomy of arthroscopy?
Vasculature -
- traveling inferior to superior just anterior to ear is the superficial temporary Art. and V. (posterior to puncture site)
- Travelling posterior to anterior are the Transverse Facial Art. and V.
Nerve = Auricolotemporal nerve travels with superficial artery and vein
If your scope or needle travels deeper than 25mm what complications are you likely to run into?
damage to tympanic membrane and ossicles of middle ear
Sequence of level 1 arthroscopy?
Exam under anesthesia (mark patient and open patient)
Insufflation (3-5 mL)
Puncture
Lavage (200-350 mL) - requires exit port
Diagnostic sweep
- looking for synovitis, adhesions/ plica formations, and chondromalacia
Lysis of adhesion
Deposit medications
Manipulate jaw in ROM under GA
What are the 7 points of interest within the superior joint space that should be examined on arthroscopy?
- Medial synovial drape - vertical striae is normal ( white/avascular) medial posterior portion of space.
- Pterygoid shadow - medial anterior
- Retrodiscal synovium = posterior space
- Posterior slope of glenoid fossa
- Articular disc (posteriorly)
- Intermediate zone (middle)
- Anterior recess - vascular hump contains temporal vessel
What is synovitis?
Inflammation of the synovial lining that lead to effusion then necrosis and scarring with adhesions and stenosis.
Worst case is fibrous anklyosis
Inflammation is caused by triggering event
what are 3 theories of synovitis triggering events?
- Direct mechanical model - leads to physical disruption and ischemia of normal cell population causing necrosis
- Hypoxia reperfusion = loading of joint causes elevated local hydrostatic pressure causing hypoxia which then reperfuses on opening rapidly causing increase in O2 free radicals causing scarring and necrosis
- Neurogenic Inflammation = peripheral nerve irritation causes release of neuropeptide Substance P which releases cytokines causing inflammation and necrosis/scarring
Synovitis presentation
- petechiae
- blood vessels
- pan synovitis = sloughing of tissue
- adhesions
- Chondromalacia = crystalline formation
What medications can be placed in joint?
HA = hyaluronic acid = lubrication
Steroids = decrease inflammation
Sclerosing agents (sotradecol)
Do patients need post op PT?
yes - can be at home or with PT
What is level II arthroscopy? Sequence?
Operative Arthroscopy double puncture
Sequence remains the same - exam under GA, insufflation, puncture, lavage, diagnostic sweep…
level two = measurement of first scope depth with second puncture at anteriro recess of superior joint space.
Once second puncture is in place you can perform operative procedures with direct visualization from original puncture.
complete operation, add medications, and manipulate jaw under GA
how do you place your second puncture?
First puncture scope is directed to anterior recess of superior joint space under direct visualization.
At this point you measure your cannula then place a needle which can be visualized then add second cannula - this is your device channel
What is level III arthroscopy?
Discopexy - triple puncture
complications of arthroscopy?
CN VII palsy
infection
hearing loss
bleeding-always have consent for open
facial scarring
auriculotemporal paresthesia
occlusion changes
puncture into brain cerebrum/through glenoid fossa (very thin bone!)
puncture into middle ear/ossicles
puncture through medial aspect of capsule
What are 3 open approaches to the TMJ?
Preauricular
Endaural
Posterior Auricular-not common
how does a MITEK anchor work?
Mitek is placed in posteior pole of the condyle .
Disc is repositioned
Sutures from mitek to disc to hold in position
Mandibular dislocation treatment options
?
Eminectomy+/-arthroplasty
can do open or arthroscopically
sclerosing agents via arthroscopy = chemical contracture (sotradecol) can also use cautery and laser on retrodiscal tissue
Patient is kept in elastics ( orthodontic brackets) to keep in class I while tissue scars (6-8 weeks)
What is synovial chondromatosis?
Small radioopacities within the joint space
noninflammatory, but affects function
can cause erosion into cranial base as it is aggressive
how do you treat synovial chondromatosis?
Open procedure and remove all loose bodies. Debride joint thoroughly.
Indications for discectomy?
failed arthroscopy
disc cannot be preserved due to deformity or perforation
Interpositional grafts?
Fat graft, temporalis, alloplastic, skin, ear cartilage, temporary silastic
Disc anatomy
Anterior band = attached to lateral pterygoid muscle
Intermediate band = thinnest zone, point of contact with condylar head
Posteior band= thickest are
Bilaminar zone = dorsal attachment
Postoperative management of Open discopexy?
PT
NSAID and muscle relaxants
Bite split and soft diet
Remove silastic implant if used at 8 weeks or sooner if crepitus occurs
If condylar resorption is noted on imaging (pan) what should you do?
Get blood work/serologies!
Pain may be on nonresorbed side due to burnout
Success of TJR operations decreases if patient has had __ prior open TMJ surgeries??
three prior open TMJ procedures due to scarring
What should you test for prior to TMJ alloplastic replacements?
Metal allergy - allergist workup
Nickel is common metal
The condylar head of the TMJ concepts custom replacement must sit wear in the fossa?
middle of posterior wall/lip
Indications for TJR?
Refractory inflammatory arthritis
Recurrent fibrous or bony ankylosis
failed alloplastic or tissue TMJ reconstruction
Loss of vertical mandibular height or VDO from trauma, bone resorption, developmental abnormality, pathology
What is the approach/access for TJR?
- preauricular and submanidbualr/retromandibular
- condylectomy +/- coronoidectomy ( gap arthroplasty)
- Place patient into IMF
- try in and secure implants and verify occlusion (fossa first for tryin, then condyle, then both before securing)
- fat graft around implants
when is fat grafting absolutely indicated?
in patients that demonstrate heterotropic bone formation.
some argue its always needed (wolford)
TJR post op recommendations?
Guiding elastics (heavy for 4-5 days) after surgery to prevent dislocation.
Analgesics for 2-4 weeks
PT- too much can open up hematomas
Prophylactic ABX for 2 years or for life
When are autogenous TJR indicated?
children and Idiopathic condylar resorption
what is gold standard for autogenous TJR?
Costochondral graft harvest
secured with screws
post op is soft diet for 3-6 months
MMF for 1-4 weeks
gentle PT
Common complications to rib grafting?
Pneumothorax
rib fracture
ankylosis of joint!
rib resorption in joint space
limited opening
Causes of condylar resorption?
Inflammatory arhtitis, Joint compression, trauma, OA, hormonal imbalance
all these can all produce inflammation
Inflammation that releases cytokines
Cytokines induce osteoclasts that resorb bone
Importnat cytokines in TMJ resorption?
RANKL, IL-6, TNF-A
What enzymes do Osteoclasts produce that resorb bone?
What activates these enzymes?
What regulated theses enzymes?
MMP’s = matrix metalloproteinases
Activated by cytokines and free radicals and cellular stress (inflammation and compression/bruxism)
Regulated by Vitamin D, estradiol (female susceptibility) , osteoprogerin
What medications can be used to combat primary arthritic cases?
TNF alpha inhibitors including etanercept (enbrel), infliximab (remicade), adalimumab (humira)
these can increase risk for infection, TB, lymphoma, leukemia, and demyelinating diseases
what antibiotics can inhibit MMPs?
Tetracycline and Doxycycline
In TJR replacements, what vasculature is on the medial of the condyle?
what may be considered regarding this?
Internal maxillary Artery
consider CTA, possible preop embolization with ICU overnight stay
Whats the difference between 1 stage and 2 stage TJR?
1 stage = implants placed immediately
2 stage = gap arthroplasty, then allow healing and workup, then second surgery to place implants
