Internal Derangement of TMJ,ankylosis, Flashcards
define internal derangement of TMJ
disorder of TMJ in which articular disk is in an abnormal position as it relates to the condyle and fossa when the teeth are in occlusion.
what can malposition of the articular disk lead to? (4)
-pain
-instability
-dec range of motion
-abnormal mobility of mandible
6 etiologies of internal derangement of TMJ
-trauma
-joint laxity
-parafunctional habits
-altered joint lubrication system
-anchored disk phenomenon (disk adhesion to articular fossa)
-myofascial pain dysfunction
-dec max incisal opening
-deviation
-deflection
-palpable clicks (reciprocal)
-crepitus
-patients complain of pain in preauricular region
internal derangement of the TMJ
Imaging dx for internal derangemeent of TMJ
MRI-T1 and T2. Disk is normally displaced in an anteriomedial vector
-osseous changes
-abnormal contours of disk
disk displacement w/o reduction
patient attempts to open but condyle can’t pass over posterior band of disk.
what do you see with disk displacement w/o reduction
deflection to the ipsilateral side
decreased excursion to contralateral side
what is disk displacement w/ reduction when patient opens what happens?
patient opens mouth w/ click that is produced when condyle passes over posterior part of disk
-during opening the disk returns to normal anatomical position
-during closing , a second click can be appreciated as the condyle passes back over the thickened posterior portion of the disk.
what classification classifies the degree of internal derangement and provides guidance in treatment options?
Wilkes classification
stage I-V
Wilkes stage 1 radiographic findings
anterior disk displacement
normal disk contour, no osseous changes
Wilkes stage 1 clinical findings
painless clicking
no pain
no locking
Wilkes stage 1 surgical findings
normal disk noted and displaced anteromedially
Wilkes stage II clinical findings
occasional painful clicking with intermittent locking
wilkes stage II radiographic findings
anterior disk displacement w/reduction on opening
mild disk deformity w/ no osseous changes
wilkes stage II surgical findings
disk thickened and displaced anteriormedially
wilkes stage III clinical findings
-frequent painful clicking w/ severe limitation in range of motion
-joint tenderness
wilkes stage III radiographic findings
anterior disk displacement w/o reduction
moderate disk deformity
no osseous changes
wilkes stage III surgical findings
deformed disk and displaced anteromedially
-adhesions may be appreciated
wilkes stage IV clinical findings
-restricted range of motion with chronic pain and joint crepitus
wilkes stage IV radiographic findings
anterior disk displacement w/o reduction
marked disk deformity w/ osseous changes
wilkes stage IV surgical findings
disk perforated w/ osseous changings of the condylar head and fossa
wilkes stage V clinical findings
joint pain and crepitus
wilkes stage V radiographic findings
disk displaced
marked disk deformity w/ severe osseous changes
wilkes stage V surgical findings
disk perforated w/ severe osseous changes of the condylar head and fossa.
6 tx of internal derangement of TMJ
-conservative tx
-intra-articular injections w/ local anesthetic/steroid mixture
-arthrocentesis w/ or w/o arthroscopy w/ repositioning
-meniscectomy w/ or w/o graft replacement
-modified condylectomoy
-post op physical therapy
2 classification systems of ankylosis
Sawhney Type 1-4
Topazian stage 1-3
Topazian stages
stage 1-only condyle
stage 2-extends to sigmoid notch
stage 3-entire condyle,sigmoid notch and coronoid
sawhney type 1 and type 2
type 1-flattned condylar head w/ close approximation to joint space
type 2-flattened condyle close to glenoid fossa,bony fusion on outer surface of articular surface. No fusion of medial joint space
sawhney type 3 and 4
type 3-bony block bridging the mandibular ramus and zygomatic arch
type4-wider boney block bridges the mandibular ramus and zygomatic arch, completely replacing architecture of joint
adult tx of tmj ankylosis
prosthetic joint
pediatric tx of tmj ankylosis
7 step KABAN protocol
7 step Kaban protocol
1.aggressive resection of fibrous/bony ankylotic mass
2.coronoidectomy on affected side and measure intra op MIO
3.coronoidectomy on contralateral side if can’t achieve MIO>35 mm and/or to the point of dislocation of the unaffected TMJ
4.Lining of the TMJ w/ temporalis myofascial flap or disk if salvageable
5.reconstruction of ramus condyle unit
6.early mobilization of jaw
7.aggressive physiotherapy
2 ways to reconstruct ramus condyle unit
-distraction osteogenesis
-costochondral graft
reconstruction of ramus condyle unit with distraction osteogenesis, when do you activate?
when do you mobilize?
activate in 2-4 days
mobilize day of operation
reconstruction of ramus condyle unit with costochondral graft, how long do you put in maxillary-mandibular fixation?
when do you mobilize?
10 days IMF
mobilize after 10 days of IMF
what takes advantage of the fibrocartilaginous cap that forms on the advancing front of the distracted bone heading toward the fossa
distraction osteogenesis
2 tx for fibrous ankylosis
-lysis of adhesions and fibrosis
-diskectomy
post op radiation tx for ankylosis
radiation therapy, 20 Gray in 10 fractions to prevent recurrence and consider when using autogenous grafting as the risk of recurrence is higher
how much rib can be harvested from child
7-10 cm
how much rib can be harvested from adult
12-17 cm
which ribs can be harvested and why
ribs 4-7 bc they have direct cartilaginous connection to the strernum.
what rib is mostly harvested and why?
rib 6, as incision falls in the inframmamary crease creating a better cosmetic outcome
which side of rib to harvest?
right side- less confusion w/ cardiogenic pain
-contralateral to side of defect to allow appropriate curvature.
rib harvest, describe incision
sharp incision inframammary crease 5 cm long
dissection of rib harvest is
subcutaneous tissue
fascia
plane btwn pec major and rectus abdominis
what is used to straddle the 5th & 6th intercostal space
2 fingers
after dissection of
subq tissue
fascia
plane btwn pec major and recutus abdominis what is then done?
sharp incision cut through periosteum down to the outer cortex of the rib
-molt periosteal to dissect in subperiosteal plane
what is doyen rib stripper associated with
pleural tears
after you get to subperiosteal plan what do you do?
sharp blade to make the cartilagious incision then pull rib laterally and protected rib cutter to section rib
why is it impt to not harvest more than 3 cm , no less than 1 cm in children
avoid overgrowth of the rib and to prevent seperation of the cartilaginous cap
how to check for pleural tears during rib harvest?
fill cavity with normal saline and have anesthesia perform valsava to check for bubbles
what do you close periosteal sleeve during rib harvest and why
3-0 polygalactin, may promote denovo regeneration of the missing rib in the child
fascia btwn rectus and pec major is closed with
3-0 resorbable suture then close subq and skin.
why do you get post op chest x ray after rib harvest?
rule out pneumothroax
rule out hemothorax
after rib harvest when can patient return to normal activity
7 days, strenous activity in 6 weeks.
3 complications of rib harvest
-cartilaginous cap seperated from harvested rib
-pneumothorax
-pleural tear
txcartilaginous cap seperated from harvested rib
-drill hole through width or rib and tie nonresorable suture to secure cap
-harvest second rib above, rib directly above is preserved to prevent cosmetic defect.
tx
-pneumothorax
-10% or less in size can be left to resorb with serial xrays
-100% pneumothorax required needle decompression by placing iv catheter at 2nd intercostal space along mid-clavicular line and listen for rush of air
-tube thoracostomy
tx
-pleural tear
suction cathether placed in wound, purse string suture through the tear, suction catheter removed under suction while tighteningt he purse string simultaneously
tube thoracostomy incision
2-3 cm incision at 5th intercostal space
-proximal end of thoracotomy tube is clamped and advanced over 6th rib avoiding neurovascular bundle on inferior border of 5th rib
-tube is placed to water-sealed suction drainage
what is it called when condylar head is anterior to the articular eminence causing open lock
hypermobility/dislocation/mandibular subluxation resulting in an inability to close from patient’s max incisal open position
2 acute tx for dislocation
bimanual mandibular manipulation in a downward and posterior vector
wrap head with barton bandadge for a week to allow stretched tissues to heal
5 chronic tx for dislocation
intra articular injection of sclerosing agent-alcohol or autogenous blood
-botox in lateral pterygoid
-LeClerc/Dautrey procedures-zygomatic arch osteotomites
-eminectomy
-lengthening articular eminence w/ bone graft from calvarium,symphysis,ramus.
