Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Oral Board Review Textbook > TMJ > Flashcards

TMJ Flashcards

1
Q

What type of joint is the TMJ?

A

Ginglymoarthrodial joint with translational movement in the superior joint space and rotational movement in the inferior joint space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the capsular ligament?

A

-Also known as the joint capsule
-Surrounds the joint
-Attaches to the temporal bone and surrounds the condylar head/neck circumferentially
-Lined by synovium which provides nutrition and immunosurveillance and lubricates the joint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the other ligaments of the TMJ?

A

-Collateral ligaments
-Temporomandibular ligament
-Sphenomandibular ligament
-Stylomandibular ligaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the articular disk of the TMJ?

A

-Fibrocartilage disc made of 3 zones (anterior, intermediate and posterior)
-Posterior to the disk is the retrodiscal tissues which are highly vascular and innervated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is movement of the TMJ determined?

A

Muscles of mastication (masseter, lateral pterygoid, medial pterygoid, and temporalis) as well as inframandibular accessory muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the vascular supply to the TMJ?

A

-Branches of superficial temporal, maxillary, and masseteric arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the nerve supply of the TMJ?

A

-Branches of auriculotemporal
-Contributions from masseteric and posterior deep temporal nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is myofascial pain dysfunction?

A

-Non-articular TMJ disorder
-Presents as a dull regional masticatory myalgia
-Worsens with function and can lead to decreased ROM
-Can involve muscles of mastication and any combo of supra/infra mandibular muscle groups

-Most common TMJ disorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are possible etiologies of myofascial pain dysfunction?

A

-Parafunctional habits (bruxism, nail biting, clenching, gum chewing)
-Life stressors
-Apertognathia or OJ greater than 6 mm
-Lack of posterior dentition leading to muscle hyperactivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are clinical manifestations of myofascial pain dysfunction?

A

-Jaw tenderness at muscles of mastication
-Wear facets
-Sore teeth
-Decreased ROM
-Buccal exostoses
-Pain at side of face, diffuse pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is degenerative joint disease?

A

-Chronic inflammatory arthritis withint he TMJ resulting in degradation of articular cartilage with remodeling of the subchondral bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the etiology of osteoarthritis?

A

-Non-inflammatory degenerative joint disease
-Due to an imbalance between catabolic and anabolic processes
-Leads to expression of catabolic cytokines (TNF-a, IL-1, IL-6)
-This initiates liberation of collagenases and proteases that result in degradation of the articular cartilage

-OA can be preceded by internal derangement and trauma. Can also develop in patients that have had orthognathic surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the etiology of inflammatory arthritis?

A

-Joint destruction due to an inflammatory arthritic process
-Includes rheumatoid arthritis, juvenile rheumatoid arthritis, psoriatic arthritis, gout, pseudogout, ankylosing spondylitis, reactive arthritis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the treatment of degenerative joint disease?

A

-Depends on extent and the level of life disruption. May include medications, PT, or steroids, or disease modifying drugs
-For mild cases failing conservative treatments, consider arthrocentesis and arthroscopic procedures
-More advanced cases may require arthroplasty or TJR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the definition of internal derangement of the TMJ?

A

-Disorder of the TMJ in which the articular disk is in an abnormal position as it relates to the condyle and fossa when the teeth are in occlusion. Malposition of the disk may lead to pain, instability, decreased ROM, abnormal mobility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the etiologies of internal derangment?

A

-Trauma
-Joint laxity
-Parafunctional habits
-Altered joint lubrication system
-Anchored disk (disk adhesion)
-MPD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is internal derangement diagnosed?

A

-Clinical exam: Decreased MIO, deviation, deflection, palpable clicks, crepitus. Preauricular pain
-Radiographic: MRI T1 and T2. Disk usually in anteromedial vector. May see osseous changes and abnormal contours
-Disk displacement with reduction: Pt opens mouth with accompanying click (disk is in correct position when open, once closed you hear another click and disk is again anterior)
-Disk displacement without reduction: Pt attempts to open but the condyle cannot pass over the posterior band of disk. Results in decreased opening, deflection t o ipsilateral side and decreased excursion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe Wilkes stage I.

A

Clinical: Painless clicking, no pain or locking.
Radiographic: ADD noted, disk contour normal w/o osseous changes.
Surgical: Normal disk noted and displaced anteriomedially

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe Wilkes stage II.

A

Clinical: Occasional painful clicking with intermittent locking
Radiographic: ADD with reduction on opening. Mild disk deformity w/o osseous changes
Surgical: The disk appears thickened and displaced anteriomedially

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe Wilkes stage III.

A

Clinical: Frequent painful clicking with severe limitation in ROM. Pt with joint tenderness
Radiographic: ADD w/o reduction. Moderate disk deformity, no osseous changes
Surgical: Disk is deformed and displaced anteromedially. Adhesions may be appreciated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe Wilkes stage IV.

A

Clinical: Restricted ROM with chronic pain and joint crepitus
Radiographic: ADD w/o reduction. Marked osseous changes
Surgical: Perforated disk with osseous changes of the condylar head/fossa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe Wilkes stage V

A

Clinical: Joint pain and crepitus
Radiographic: Disk displaced, marked deformity with severe osseous changes
Surgical: Disk is perforated. Severe osseous changes of the condylar head and fossa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the treatment for internal derangement?

A

-Conservative treatment first line
-Intra-articular injections with local anesthetic/steroid mixture
-Those unresponsive would benefit from arthrocentesis w/ or w/o arthroscopy, arthroplasty with repositioning, or meniscectomy w/ or w/o graft/replacement or modified condylotomy
-Post-op management: Physical therapy/ROM exercises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are extra-articular causes of hypomobility (pseudo-ankylosis)?

A

-Muscle fibrosis secondary to radiation, myofascial pain, tumors, infection, hysteric trismus, myositis ossificans, fractures of the condyle, zygomatic arch, coronoid process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are intra-articular causes of hypomobility (true ankylosis)?

A

Intra-articular fusion within the joint space resulting in hypomobility.

-Can be bony, fibrous or fibro-osseous
-Can be complete vs incomplete
-Can be caused by trauma, infection, otitis media, rheumatoid arthritis, psoriatic arthritis, prolonged immobilization, previous TMJ or orthognathic surgery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is TMJ ankylosis classified?

A

Two systems. Sawhney and Topazian.

Sawhney
-Type 1: Flattened condylar head with close approximation to joint space
-Type 2: Flattened condyle close to glenoid fossa, bony fusion on outer aspect of articular surface, no fusion of medial joint space
-Type 3: Bony block bridging the mandibular ramus and zygomatic arch
-Type 4: Wider bony block bridges the mandibular ramus and zygomatic arch, completely replacing the architecture of the joint

Topazian
-Stage 1: Only condyle involved
-Stage 2: Extends to sigmoid notch
-Stage 3: Entire condyle, sigmoid notch and coronoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the work-up for a TMJ ankylosis?

A

-Clinical exam: Decreased MIO, inability to appreciate translation of condylar head
-Panorex: Can see radiodense mass overall bony morphology, coronoid hypertrophy
-CT with contrast: Defines the extent of the heterotopic bone/ankylotic mass. Delineates relationship of mass to vital structures. May aid in fabrication of custom TMJ prosthesis in setting of immediate reconstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the treatment options for a TMJ ankylosis?

A

-Requires excision of the mass w/ reconstruction
-Goal of MIO is 35 mm or greater
-Recon typically with a custom joint, other options include costochondral graft or fibular free flap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the Kaban protocol for TMJ ankylosis in pediatric patients?

A

-Aggressive resection of the fibrous and or bony ankylotic mass
-Coronoidectomy on the affected side and measure MIO intra-op
-Coronoidectomy on contralateral side to achieve MIO >35 mm
-Lining of the TMJ with a temporalis myofascial flap or the native disc if salvageable
-Recon of the ramus condyle unit with either distraction osteogenesis (activate 2-4 days. takes advantage of fibrocartilaginous cap for distracting) or costochondral graft with rigid fixation and MMF x10 days
-Early mobilization of the jaw (day of surgery for DO, 10 days for costochondral graft
-Aggressive physiotherapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the treatment options for a fibrous ankylosis?

A

Can be treated more conservatively

-Lysis of adhesions and fibrosis
-Diskectomy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the post-operative management for a fibrous ankylosis?

A

-Aggressive Physical therapy most important

-Frequent follow-up
-Consider radiation therapy 20 Gray in 10 fractions (prevent recurrence and helpful in autogenous grafting when the risk of recurrence is higher)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the size of a rib graft that can be harvested?

A

Children: 7-10 cm
Adult: 12-17 cm

From lateral edge of latissimus dorsi and costochondral junction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Which ribs can be harvested and why?

A

-RIbs 4-7
-Direct cartilaginous connection to the sternum

-Rib 6 is most common. Incision falls in the inframammary crease

33
Q

What is the dissection for the costochondral graft?

A

Avascular plane between the fusion of the rectus and pectoralis major

34
Q

Which laterality is typically used in a costochondral graft and why?

A

-Common to take right rib (least likely to be confused with cardiogenic pain

-Some advocate for contralateral side of the defect to allow appropriate curvature of the harvested rib

35
Q

Describe the technique for a costochondral graft.

A

-Sharp 5cm incision made in the inframammary crease
-Dissection carried through Subcutaneous tissue, fascia and a plane between the pectoralis major and rectus abdominis
-Two fingers are use to straddle the fifth and sixth intercostal space to prevent slipping of the instruments. A sharp incision is cut through the periosteum down to the outer cortex of the rib
-Periosteal elevator used to dissect in a subperiosteal plane around the rib
-Sharp blade used to make the cartilaginous incision. Important to only harvest 1-3cm to avoid overgrowth of the rib and prevent separation of the cartilaginous cap
-Rib pulled laterally and protected rib cutter used to section the length of the rib
-Check for pleural tears (Fill cavity with saline and have anesthesia valsalva)
-Periosteal sleeve closed with 3/0 polyglactin
-Fascia between rectus and pec major closed with 3/0 resorbable suture, followed by subcutaneous tissue and finally skin
-Post-op CXR ordered to r/o penumo/hemo thorax
-Normal activity POD #7, no strenuous activity until 6 weeks post-op

36
Q

What is the management if the cartilaginous cap has separated from the harvested rib?

A

-Drill a hole through the rib and tie a non-resorbable suture to secure the cap
-Or harvest a new rib (2 above so there is no cosmetic defect)

37
Q

How is a pneumothorax managed during a costochondral graft?

A

-Occurs when air is trapped between the visceral and parietal pleural cavity and there is a one-way valve allowing air to enter but not escape
-100% oxygen
-10% or less in size can be left to reabsorb with serial xrays, if doesn’t resolve in 1 week do a tube thoracostomy

-If immediate pressure release is required, complete needle decompression by placing an IV catheter at the 2nd intercostal space along the mid-clavicular line (listen for rush of air)

-Tube thoracostomy: requires a 2-3 cm incision at 5th intercostal space, just above the 6th rib. Local infiltrated. Proximal end of a thoracotomy tube is clamped and advanced over the 6th rib (avoid neurovascular bundle). Tube placed on water-sealed suction drainage

38
Q

How is a pleural tear managed during a costochondral graft?

A

-Air bubbles appreciated during valsalva maneuver
-Suction catheter is placed into the wound and a purse string suture through the tear
-The suction catheter is removed under suction while tightening the purse string simultaneously

39
Q

What is an open lock episode?

A

-Happens with hypermobility/dislocation

-Inability for patient to close from MIO
-Condylar head anterior to articular eminence

40
Q

What are possible etiologies of an open lock/dislocation?

A

-Excessive yawning
-Excessive/prolonged opening (dental appt)
-Seizure disorder
-Intubation
-Tardive dyskinesia
-Phenothiazine treatment
-Connective tissue disorders (Ehlers danlos, Marfans)

41
Q

What is the acute treatment for open lock?

A

-Reduction by bimanual mandibular manipulation in a downward and posterior vector (consider sedation)
-Wrap the head with a Barton bandage to limit jaw movements for 1 weeks (allows stretched tissues to heal)

42
Q

What is the treatment for chronic open lock/dislocation?

A

-Noninvasive measures include intra-articular injections of a sclerosing agent (alcohol or autogenous blood) in the superior joint space
-Botox used in the lateral pterygoid
-LeClerc/Dautrey procedures (Zygomatic arch osteotomies), eminectomy, lengthening the articular eminence with a bone graft (calvarium, symphysis, ramus)

43
Q

How do you order an MRI for a TMJ patient?

A

-Order with T1 and T2 weighted images
-3 mm serial cuts in coronal, sagittal, and axial views for both open and closed mouths

44
Q

What does a normal TMJ MRI show?

A

-Junction of the posterior band and the posterior attachment at the 12 O’ Clock position in a closed mouth

45
Q

What is T1 imaging and what is seen in T1 TMJ imaging?

A

-Fat appears bright and will appear white
-Better for anatomy evaluation
-Marrow fat in condyle will have a high T1 signal intensity
-Can tell if an image is T1 is if condyle is white, the gyri of the brain DO NOT show white banding, or the orbits appear grey
-Disk and cortical bone are black in both T1 and T2

-If there is avascular necrosis, T1 marrow will be black and T2 will be bright due to necrosis

46
Q

What is T2 imaging and what is seen in T2 TMJ imaging?

A

-Water is bright and fat is dark
-Brain appears grey w/ white branding
-Better to look for effusions and pathology
-Bone marrow is less bright (condyle grey)

47
Q

What is your subjective exam for a TMJ patient?

A

CC: Ask patient to expound on the chief complaint.

HPI (Use OLD CARTS)
-Onset
-Location
-Duration

-Character (characterize pain)
-Aggravating/associated symptoms)
-Relieving
-Timing
-Severity

48
Q

What is your physical exam/work-up on a TMJ patient?

A

-Inspection: Look for gross asymmetry of the face, signs of occlusal trauma, loss of posterior teeth

-Palpate: Palpate muscles of mastication, cervical musculature, preauricular region

-Assess mandibular gait: MIO, excursive movements, protrusive movements, deflection, deviation

49
Q

What is Mahan’s sign?

A

Place a tongue blade on canine

-If there is ipsilateral preauricular pain, then there is an internal deranagement of the ipsilateral joint

50
Q

Describe what you can see in a Panorex in relation to TMJ evaluation.

A

-Condyles in fossa?
-Degenerative changes to condylar head?
-Loss of joint spacing?
-Subcortical cysts?
-Chondromatosis (joint mice)?
-Subchondral eburnations (sclerosis)?
-Osteophytes?
-Radiodense changes or coronoid hypertrophy indicative of ankylosis
-Condylar hyperplasia, hypoplasia or agenesis

-Look at surroundings: 3rd molars, fractures, caries, perio, sinus pathology

51
Q

Describe what you can see on an MRI in relation to a TMJ evaluation.

A

-Get T1, T2 weighted, open and closed mouth views
-Assess disk position, disk integrity, condition of condyles
-T1 better detail of joint anatomy, T2 useful for inflammatory changes and effusions
-T1 fat bright, T2 water bright
-Brain in T2 has bright gyri and periorbital tissues

52
Q

Describe what you can see on a TMJ arthrogram in relation to a TMJ evaluation.

A

-Plain film to visualize TMJ with contrast
-Good to visualize the position of the disk and assess for perforations

53
Q

Describe what you can see on a CT with contrast of the TMJ

A

-Look for ankylotic masses, neoplasms, mechanical obstruction, infectious causes of trismus
-Contrast helps to delineate the proximity of blood vessels to an ankylotic mass or a collection of an infection

54
Q

What are the indications of arthrocentesis?

A

-Acute closed lock
-Previous surgery with continued discomfort
-TMJ arthralgia
-Wilkes classification 1, 2, and 3

55
Q

What are the contraindications for arthrocentesis?

A

-Ankylosis
-Overlying skin infection
-Inability to appreciate the regional anatomy (obese patient)

56
Q

What is the technique for an arthrocentesis?

A

-Draw out the canthal-tragal line (Holmlund-Hellsing line)
-First point 10 mm ahead of line and 2 mm below. Corresponds with glenoid fossa
-Second point 20 mm ahead of line and 10 mm below. Corresponds with height of the articular eminence
-Prep skin with antiseptic solution
-Use local anesthetic w/o epi to anesthetize area
-Manipulate the jaw to open the joint space
-Insufflate superiro disk space with 27-gauge needle with LR
-Use an 18 gauge needle (45 degrees), superior and anteriorly to reach lateral aspect of zygomatic arch, walk needle off the bone and enter the superior joint space (anterior port). Average 25 mm deep to skin, 3 cc volume in space
-Place posterior port in similar manner with 18 gauge needle
-Irrigate with LR (at least 100 mL). Lavaging the joint can break up adhesions and allow the disk to recapture into its premorbid position. This also irrigated out inflammatory mediators
-Remove anterior port and inject (Kenalog 40 mg/mL with 0.5% bupivacaine 0.5% with 1:200k epi)
-Manipulate joint under anesthesia and check opening under sedation
-Post-op management includes aggressive ROM exercises, NSAIDs, splints

57
Q

What are the indications of a disk repositioning procedure?

A

-Surgical procedure to manually reposition the disk into its premorbid position
-Indications are failure of conservative therapy, Wilkes 2-5

58
Q

What is the technique for disk repositioning procedure?

A

-Ear pack, local anesthesia
-Incision marks in the preauricular crease
-Incision made through skin and subcutaneous tissue for the entire length
-Attention is directed in the superior portion of the incision. Dissect through temporoparietal fascia and auricularis anterior muscle down to the temporalis fascia (glistening white)
-The temporal branch of the facial nerves runs within the TP fascia anywhere from 8-35 mm (average 20 mm) from the bony extent of the external auditory meatus
-The remaining intervening tissue are dissected down to the level of the temporalis fascia using a nerve monitor/stimulator to avoid the course of the nerve
-Palpate zygomatic arch, incise through the attached periosteum. Dissect subperiosteally until you appreciate the joint capsule
-Insufflate the joint with LA, make an incision into the joint capsule to enter superior joint space
-Mobilize the disk
-Assess for perforations (can repair small perforations vs remove disk)
-Disk can be plicated in a posterolateral vector to the disc capsule or temporalis fascia with a non-resorbable suture or Mitek anchor
-Layered closure

59
Q

What is the management of otitis externa from TMJ surgery?

A

-Infection of the external auditory canal
-Pt complains of pain on movement and pressure of the ear
-Otoscopy will reveal edematous EAC with possible discharge
-Treatment with topical floroquinolone (cover pseudomonas)

60
Q

What is the management of otitis media from TMJ surgery?

A

-Inflammation of the middle ear structures
-Patient complain of ear pain, difficulty hearing, and fever
-Otoscopy shows full or bulging tympanic membrane or purulence
-Treat with amoxicillin
-Consider ENT for myringotomy tubes

61
Q

What is the management of a broken instrument during arthroscopy/arthrocentesis?

A

-If you are able to visualize the fragment, and having arthroscopic training, attempt removal arthroscopically
-If you can’t visualize, obtain radiographs in multiple planes for ID
-Convert to an open approach for removal

62
Q

What is the management of tympanic membrane rupture/hemotympanum from TMJ surgery?

A

-Otoscopy to examine for TM rupture or hemotympanum
-Consult ENT for intra-op examination if noted
-If EAC is damaged, place an antibiotic impregnated sponge dressing, suture to maintain opening of EAC
-Consider antibiotic-hydrocortisone suspension x14 days
-Monitor for granulation tissue and remove as needed

63
Q

What is the management if there is a violation of the middle cranial fossa from TMJ surgery?

A

-Fossa is only 0.9 mm thick
-If large perforation is noted, obtain an intra-op NSGY consult
-If CSF leak suspected post-op, obtain CT scan/MRI (with NSGY consult)
-Pt placed on bedrest with HOB greater than 30 degrees
-Place on cotrimoxazole (bactericidal and enters CSF)
-Most small leaks spontaneously heal within 1 week

64
Q

What is the management if there is damage to the temporal branch of the facial nerve?

A

-Range 8-35 mm average 20 mm from bony external auditory canal
-Innervates frontalis, orbicularis and currugator supercilli muscles
-Most resolve in 3-6 months
-Start with observation
-Treatment for symptomatic patients
-Ophthalmology consultation
-Lubrication and taping of the eye at night (prevent keratoconjunctivitis)
-Physical therapy with electrical stimulation (maintain muscle tone while healing)
-Gold weight implants can be placed in upper eyelid for permanent defects

65
Q

How is auriculotemporal nerve syndrome managed (Frey Syndrome)?

A

-Gustatory sweating, flushing, and warmth over temporal/pre-auricular areas
-Occurs when auriculotemporal nerve is damaged (mostly during arthroscopy)
-Usually temporary and resolves within 6 months
-Can evaluate with Minor test (solution of iodine, castor oil and alcohol applied to both preauricular regions, gustatory sweating is elicited by having patient chew on lemon drop. Positive test is when yellow mixture turns blue)

-Case reports have shown 16-80 IU of botulism A subcutaneous injection resulted in resolution within 1 week
-Application of scopolamine (anticholinergic properties)
-Surgical transection of innervation

66
Q

What is the source of bleeding during condylotomy?

A

-Concern for bleeding of the internal maxillary artery and branches
-IMAX runs 3 mm medial from the mid-sigmoid notch and 20 mm below the condylar head
-ALso concern for damage to masseteric artery when cut through sigmoid notch

67
Q

What is the source of bleeding during a diskectomy?

A

-Retrodiscal tissue
-Lateral pterygoid muscle
-Middle meningeal artery (31 mm medial to the zygomatic arch and 2.4 mm anterior to the height of the glenoid fossa

68
Q

How is bleeding managed during TMJ surgery?

A

-First step is visualization
-Atempt to identify any vessels for cauterization or ligation
-If unable to identify, apply firm pressure with moistened gauze, packed tightly in wound
-Try thrombin soaked gauze, flowable hemostatic agents, collagen sponges. Hold pressure for at least 5 minutes
-Interventional radiology for embolization is warranted if bleeding not controlled by local hemostatic measures

-Some advocate for carotid artery cut down, some question due to collateral circulation

69
Q

What is the technique for a carotid artery cut down for uncontrolled bleeding?

A

-5 cm incision 2 cm below inferior border of the mandible over the SCM
-SCM retracted posterior and with blunt dissection parallel to the vessels identify the carotid sheath
-Enter sheath carefully
-Retract internal jugular vein posteriorly to reveal common carotid
-Hypoglossal nerve crosses the arteries above bifurcation, identify and protect
-Ligation should occur above the facial branch (third anterior branch)
-This reduces blood flow by 73%

70
Q

What are the indications for TMJ TJR?

A

-Failed previous TMD surgeries
-Severe arthritic joint
-Loss of vertical mandibular height and occlusion
-Pathology
-Ankylosis (bony and fibrotic)
-Condylar agenesis

71
Q

What are the two TJR prostheses approved?

A

-Biomet stock TMJ (multiple sizes)
-TMJ concepts custom

72
Q

What are the materials of the Biomet Stock TMJ?

A

-Chronium cobalt alloy for condylar component
-Ultra-high molecular weight polyethylene for fossa component

-If unilateral, pseudotranslation possible due to push of contralateral TMJ

-Sizes of chronium cobalt (condylar component) are 45, 50 or 55 mm with standard, narrow or offset styles

-Chromium cobalt may contain nickel, be aware if allergy

73
Q

What are the materials of a TMJ Concepts TMJ?

A

-Pure titanium for condylar component
-Pure titanium with ultra high molecular weight polyethylene for the fossa component

74
Q

What is the surgical technique for a TJR?

A

-Place pt in MMF

Preauricular approach:
-Standard preauricular approach to joint capsule
-Make an incision in periosteum of lateral aspect of condylar head in a T shape fashion. Expose the lateral aspect of the condyle
-Dissect subperiosteally to expose the anterior and posterior regions of the condylar neck
-Pack site and direct attention to submandibular approach

Submandibular approach
-2cm below inferior aspect of mandible
-Inject vasoconstrictor
-6 cm incision
-Dissect skin and subcutaneous tissue to platysma
-Undermine skin
-Sharp dissection through platysma exposing the superficial layer of the deep cervical fascia. Dissect through this layer with nerve stimulator to protect marginal mandibular nerve (Within or deep to the fascia)
-ID and clamp facial artery/vein
-Divide pterygomasseteric sling along inferior border of mandible

Condylar resection
-Condyle retractors placed to isolate the neck of the condyle
-Resect exposed condyle (minimum of 15 mm for clearance of condyle/fossa component)
-Inadequate removal may lead to impingement of ramus remnant on fossa prosthesis with MMF

Fossa Preparation
-Reduce fossa noted on pre-op model to accommodate prosthesis
-Secure fossa with instrument from TMJ concepts, secure two screws

Condyle component
-Place in MMF
-Secure 2 screws

Final screw securement
-Cover wounds, enter mouth and remove MMF
-Ensure ROM (may need coronoidectomy) and occlusion
-Secure rest of screws (4 total in fossa, 6 in ramus)
-Irrigate and close
-Consider fat graft around fossa to prevent ankylosis

75
Q

Describe your post-op regimen for a TMJ TJR patient.

A

-Post-op radiographs to confirm position and alignment
-Post-op exercises and soft diet
-Consider PT for 4-6 weeks

76
Q

What liquid and volume do you use for arthrocentesis and why?

A

-At least 400 mL of LR
-Adequate in reducing inflammatory markers of the TMJ (IL-6, bradykinin)

-LR is a crystalloid solution containing CaCl, KCL, Sodium lactate. It is close to human serum make-up and well tolerated

77
Q

Why is HA used as an injection with arthrocentesis?

A

-Mimics glycosaminoglycan made by synovial cells
-It is viscous, high molecular weight that lubricates and protects articulating surfaces

78
Q

What is the rationale for condylotomy?

A

-Goal is to increase joint space and unload the disk to relieve pain (allows condylar sag)

-Procedure is to access like an IVRO with medial pterygoid muscle release to allow for condylar sag
-Posterior cut 6-8 mm from posterior border and 10 mm from sigmoid notch
-Goal is to achieve 3-4 mm of condylar sag (looking at inferior border and tip of proximal segment)

79
Q

What is your post-op protocol for a condylotomy?

A

-Post-op orthopantogram
-7 days of IMF (unilateral), 14-21 days of IMF (bilateral)
-Elastics and physical therapy
-Remove arch bars in 7 weeks

Oral Board Review Textbook (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions