Учебники / Color atlas of temporomandibular joint surgery Quinn
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Chapter five |
Osseous Surgery of the Temporomandibular Joint |
103 |
FIG. 5.6
A sagittal MRI of a patient with chronic subluxation. Note the exaggerated translation of the condyle anterior to the articular eminence. The anterior band of the meniscus is in a distal position relative to the condylar head.
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Color Atlas of Temporomandibular joint Surgery |
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FIG. 5.7
A
A, Initiating osteotomy of articular eminence with 1-mm fissure bur. Approximately 90% of the cut is
performed with the bur. |
Continued |
Chapter Five |
Osseous Surgery of the Temporomandibular joint |
105 |
FIG. 5.7, CONT'D
B
B, Completing emineclomy with osteotome. Note inferior angulation to ensure that the bony cut slays
below the base of the skull.
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Color Atlas of Temporomandibular Joint Surgery |
FIG. 5.8
A
B
c
A, The superior joint space status postarticular emineclomy. Note that theoretically the procedure affords great freedom of movement to the articular disk as well as lessens the chance of condylar dislocation. The dotted line denotes the amount of bone removed during the emineclomy procedure. Removal of the convex ridge of the eminence in its entire medial extent is critically important to relieve the impingement of the condyle against the meniscus. B, Bony perforations placed in articular eminence with 1-mm Fisher bur to outline articular emineclomy. C, Status posteminectomy. Approximately 18 mm of the eminence was removed to ensure an unobstructed path of condylar translation.
Chapter Fife |
Osseous Surgery of the Temporomandibular Joint |
1-mm fissure bur positioned for lateral cortical eminectomy cut.
Inferior view of articular eminence showing full extent of area that needs to be reduced during the emineclomy procedure.
107
FIG. 5.9
FIG. 5 . 10
108 |
Color Atlas of Temporomandibular Joint Surgery |
FIG. 5 . 1 1
A B
A, B, Combination articular eminenectomy with meniscal plication. The patient had sustained excessive stretching and laxity in the posterior attachment secondary to chronic subluxation.
FIG. 5.12
An MRI showing the bright signal of the marrow in the articular eminence. Imaging of the structure of the articular eminence before emineclomy is extremely important to prevent possible perforation into the middle cranial fossa with exposure of the temporal lobe and possible leaking of cerebrospinal fluid.
Chapter hive |
Osseous Surgery of the Temporomandibular Joint |
109 |
FIG. 5 . 13
A
B
A, A large, round diamond bur placed in position to remove the inner ridge of the articular eminence. Note that the eminence must be contoured to the full extent of its medial extension to achieve adequate reduction in the bony contour. Also note the use of a broad, flat elevator to depress and protect the meniscus and condyle from inadvertent damage caused by the diamond bur. B, Large, round diamond bur
used to contour medial osteotomy cut. Continued
1 1 0 |
Color Atlas of Temporomandibular joint Surgery |
FIG. 5.13, CONT'D
c
C, After eminectomy is completed, the mandible is manipulated to ensure unobstructed condylar motion
during normal range of motion.
Chapter Five |
Osseous Surgery of the Temporomandibular Joint |
111 |
FIG. 5 . 14
A B
A, View of o palienl with chronic subluxation showing condyle-disk relationship at normal range of motion immediately before excessive motion, which results in anterior subluxation. B, Status postarticulor emineclomy. Note the depth of surgical recontouring to eliminate condylar-eminence contact.
FIGS. 5.15, 5 . 16
Autogenous or allogeneic bone or prosthetic implants have been used to lengthen the steepness of the articular eminence and thereby decrease the hypermobility of the condyle and prevent dislocation.
An alternative method to lengthen the articular eminence is the Dautrey procedure, in which the zygomatic arch is osleolomized and then fractured in an inferior position. Il is subsequently secured to the depth of the articular eminence to lengthen the slope of the anterior eminence.
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Color Atlas of Temporomandibular joint Surgery |
CONDYLECTOMY
As an isolated procedure for joint pain, condylectomy has been largely abandoned. It is a necessary surgical maneuver to treat ankylosis and prepare the joint for a total alloplastic prosthesis or a costochondral graft. The procedure involves a standard preauricular approach, with special emphasis on visualizing the base of the condylar neck at the level of the sigmoid notch.
Many surgeons also complete the inferior dissection through a modified posterior mandibular incision before the condylectomy. This procedure allows digital access to the medial surface of the ramus (from below) to apply pressure to the internal maxillary artery in the event it is severed while the condyle is sectioned. Because of the proximity of the artery to the condylar neck, specially designed retractors (e.g., Dunn-Dautrey condylar retractors) should be placed before the osteotomy.
A 1-mm fissure bur is used to make a cut at the level of the sigmoid notch. The cut is made completely through the lateral, anterior, and posterior surfaces, but the_ last section of medial cortical bone is preserved. A T-bar osteotome is gentlytapped and torqued to complete the condylar cut. If bleeding occurs, the cut must be quickly completed to allow access to the area for adequate compression and ligation, if this measure is necessary. Initial control can be maintained with thrombinsoaked sheets of Avitene. Pressure and medium Hemo-clips can be used if the severed vessel can be visualized. As previously mentioned, digital compression can also be applied to the medial aspect of the ramus from the submandibular incision.
In cases of ankylosis, sectioning the condyle at a level below the ankylosis (usually at the sigmoid notch) is recommended before attempting to separate the anky-
lotic bone at the superior glenoid fossa margin.
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