Atlas of Temporomandibular Joint Surgery

CONTENTS

Cover

Title page

Contributors list

Preface

Acknowledgments

About the companion website

CHAPTER 1: Surgical decision making for temporomandibular joint surgery

CHAPTER 2: Diagnostic imaging of the temporomandibular joint

Plain film, tomograms, and orthopantogram radiography

Arthrography

Computer tomography, 3D reconstruction, and computer planning

Magnetic resonance imaging

Bone scans

Further reading

CHAPTER 3: Surgical approaches to the temporomandibular joint

Applied anatomy

Surgical approaches

Prep and positioning

References

Selected reading

CHAPTER 4: Surgery for internal derangements

Disk plication

Diskopexey

Meniscectomy (discectomy)

Meniscectomy with replacement

Modified condylotomy

Postoperative care

Suggested reading

CHAPTER 5: Osseous surgery of the temporomandibular joint

Condyloplasty

Eminoplasty

Condylectomy

Condylotomy

Further reading

CHAPTER 6: Trauma

Incidence, etiology, and pattern of fracture

Signs and symptoms associated with condylar fracture

Imaging of the temporomandibular region

Classification of fracture of the mandibular condyle

Treatment of mandibular condyle fractures

Condylar fractures in children

Further reading

CHAPTER 7: Autogenous reconstruction of the temporomandibular joint

Costochondral graft

Vascularized (fibula) graft

Distraction osteogenesis

Further reading

CHAPTER 8: Stock alloplastic reconstruction of the temporomandibular joint

Further reading

CHAPTER 9: Custom alloplastic reconstruction of the temporomandibular joint

Introduction

Surgical planning

Combined orthognathic and TMJ prosthetic reconstruction

Further reading

CHAPTER 10: Pathology of the temporomandibular joint

Rheumatoid arthritis

Septic arthritis

Benign tumors

Foreign body reactions

Malignant tumors

Further reading

CHAPTER 11: Complications

Nerve injury

Hemorrhage

Heterotopic bone formation

Infection

Late effects of condylar fractures

Materials failure

Ankylosis

Summary

Further reading

Index

End User License Agreement

List of Tables

Chapter 04

Table 4.1 Wilkes classification for internal derangement of the TMJ.

Chapter 06

Table 6.1 Open reduction of the fractured mandibular condyle.

Chapter 08

Table 8.1 Early alloplastic TMJ prostheses.

Table 8.2 Comparison of stock and custom alloplastic devices.

Chapter 10

Table 10.1 Neoplasms of the temporomandibular joint.

List of Illustrations

Chapter 02

Figure 2.1 Transcranial radiograph, demonstrating the limitations of this study. Note the overlap of adjacent structures with the glenoid fossa and mandibular condyle.

Figure 2.2 (a) Later oblique in the closed mouth position, note mandibular condyle seated in the glenoid fossa (inset). (b) Lateral oblique in open mouth position, note translation of TMJ condyle (inset).

Figure 2.3 Lateral cephalogram showing bilateral dislocation of the temporomandibular joints. Note anteriorly positioned mandible and open bite.

Figure 2.4 Postoperative lateral cephalogram. Study demonstrates good condylar prosthetic position and occlusal relationship.

Figure 2.5 (a) Preoperative posterior–anterior (PA) skull film. Note facial asymmetry involving the maxilla and mandible. (b) Postoperative PA demonstrating achievement of facial symmetry. Condylar prosthesis is well aligned. Note maxillary hardware from Le Fort I procedure.

Figure 2.6 (a) Patient positioned for angle-corrected temporomandibular joint tomograms.(b) Angle-corrected tomogram of right temporomandibular joint.

Figure 2.7 Tomographic technique—basic principle of tomographic X-rays. Both the radiation source and film are moving simultaneously to blur all the anatomy anterior and posterior to the point of plane convergence.

Figure 2.8 Representation of sagittal cuts in standard tomographic condylar films showing anatomy from the most lateral to the most medial cut (a) progressing medial (b, c, d) to the most medial cut (e).

Figure 2.9 Typical contours of lateral condylar tomograms in varying stages of degenerative joint disease.

Figure 2.10 (a) Temporomandibular joint-tomographic series depicting excellent osseous detail with 5 mm cuts. (b) Sclerosis and condylar head flatting. (c) Bird-beaking of condyle in late stage degeneration.

Figure 2.11 (a) Patient positioned for panoramic tomogram of the temporomandibular joints. (b) Example of programmed condylar views available on most panoramic tomographic units. (c) Bilateral positioning techniques for specific temporomandibular joint-panoramic X-ray imaging positioned to align the condyle into the center of the trough of resolution of the panoramic tomogram.

Figure 2.12 (a) Dedicated tomogram showing bilateral degenerative joint disease, note the subchondral cyst on the right condyle (arrow). (b) Panorex of same patient. Note improved anatomic detail is evident in the tomogram (a) when compared to the panorex (b).

Figure 2.13 Panorex demonstrating left TMJ bird beaking and condylar sclerosis.

Figure 2.14 Patient with temporomandibular joint osteoarthritis prior to the completion of facial growth. Note decreased ramus height (double arrow) and increased premasseteric (antegonial) notching (single arrow).

Figure 2.15 Hoof deformity in condylar head, secondary to condylar trauma during growth. Panorex (a) and status-post resection (b).

Figure 2.16 (a) Panorex of a pediatric patient with ankylosis of the temporomandibular joint. Note displaced condylar head superior to the sigmoid notch (arrow). (b) Intraoperative photo of the same patient showing the ankylosis and fibrous union of the condyle to the skull base.

Figure 2.17 (a) Preoperative panorex of a patient with facial asymmetry secondary to temporomandibular juvenile rheumatoid arthritis. (b) Immediate postoperative panorex following total joint replacement, Le Fort I osteotomy and genioplasty.

Figure 2.18 (a) Coronal computer-tomography (CT) in bone windows, showing normal temporomandibular joints. (b) Sagittal CT in bone windows, showing a normal temporomandibular joint.

Figure 2.19 Coronal CT showing early erosion of the left condyle in a patient with osteoarthritis.

Figure 2.20 Coronal CT showing bilateral sagittal fractures of the condylar heads and a right subcondylar fracture with severe lateral displacement.

Figure 2.21 Coronal CT of a pediatric patient with a left condylar head fracture.

Figure 2.22 Coronal CT demonstrating bilateral TMJ ankylosis.

Figure 2.23 (a) Axial and (b) coronal CT of a patient with right dislocated condyle.

Figure 2.24 (a) Axial and (b) coronal CT soft tissue windows with contrast of patient with septic arthritis. Note rim enhancing of the contrast around the temporomandibular joint and anterior displacement of the condyle.

Figure 2.25 (a) 3D reconstruction, (b) panorex (c), sagittal CT, (d) coronal CT, and (e) axial CT of a patient with a comminuted fracture involving the ramus and subcondylar region. Note how the 3D reconstruction aids in demonstrating the relation of the fracture.

Figure 2.26 Cone beam CT showing severe bilateral condylar resorption secondary to rheumatoid arthritis. (a) Panorex from cone beam CT. (b) Right sagittal cone beam CT. (c) Coronal cone beam CT. (d) Left sagittal cone beam CT.

Figure 2.27 (a) Preoperative 3D reconstruction used for surgical planning. (b) Planned 3D surgical reconstruction with the maxilla and mandible repositioned into the desired position, allowing for the design of the custom TMJ prosthesis.

Figure 2.28 (a) Postoperative 3D reconstruction using cone beam CT. (b) Preoperative planned position. Note artifact from cobalt-chrome prosthesis.

Figure 2.29 Diagrammatic representation showing normal condyle disk position with junction of posterior attachment and posterior band of disk aligned approximately at the 12 o’clock position with regard to the condylar surface (a) and sagittal cadaver demonstrating normal condylar-disk position (b).

Figure 2.30 Normal closed (a) and open condyle and disk position (b).

Figure 2.31 Diagram demonstrating anterior disk displacement (closed) with reduction (open).

Figure 2.32 Diagram demonstrating anteriorly displaced disk (closed) without reduction (open). Notice decreased translation movement of the condylar head.

Figure 2.33 (a) Locator image. (b) Normal closed mouth T1 MRI of the left TMJ (as indicated by the image in (a)).

Figure 2.34 (a) Normal T1 image of the TMJ in the closed mouth position. (b) Normal T1 MRI in the open mouth position.

Figure 2.35 (a, b) Open and closed views of right temporomandibular joint with early anterior disk displacement with reduction.

Figure 2.36 (a) Closed mouth T1 MRI showing anteriorly displaced disk with thickened posterior band. Note minimal osseous changes. (b) Cryosection showing early pathologic changes with anterior disk displacement. Note thickening of retrodiscal tissue.

Figure 2.37 Open (a) and closed (b) MR image of right temporomandibular joint showing anterior disk displacement without reduction.

Figure 2.38 T1 MRI in the closed mouth position demonstrating an anteriorly displaced disk with disk deformity.

Figure 2.39 T1 MRI in the open-mouth position showing an anteriorly displaced disk without reduction and bird beaking of the mandibular condyle. Loss of disk anatomy seen here is indicative of long-standing displacement and with loss of the normal disk biconcavity.

Figure 2.40 (a) Cryosection showing degenerative condylar changes and thinning of the meniscus with loss of the normal 3-1-2 disk dimension (anterior band 3mm: intermediate zone 1 mm: posterior band 2 mm). (b) MRI T1 demonstrating similar findings.

Figure 2.41 (a) Diagram showing advanced degenerative joint disease. (b) MRI showing anteriorly displaced disk with condylar degeneration, disk thinning, and posterior band thickening.

Figure 2.42 (a) Coronal MRI showing lateral disk herniation. (b) Diagram demonstrating normal disk and capsule attachments.

Figure 2.43 (a) T2 MRI with contrast demonstration anterior joint space effusion and enhancement of the retrodiskal tissue. (b) T2 MRI with contrast demonstrating superior joint space effusion.

Figure 2.44 (a) MRI, (b) panorex, and (c) cone beam CT of a patient with TMJ ankylosis.

Figure 2.45 Technetium 99 bone scan. (a) Nonspecific positive bone scan of left temporomandibular joint, secondary to psoriatic arthritis. (b) Positive bone scan with enhancement of the right temporomandibular joint secondary to condylar hyperplasia.

Chapter 03

Figure 3.1 (a) Normal condyle and fossa with mandible closed. Note the position of the disk, with the posterior aspect at the height of the condyle. (b) Mandible open. Condyle has both rotated and translated along the articular eminence. Note disk has moved anteriorly along with the condyle.

Figure 3.2 Facial nerve emerging from stylomastoid foramen showing division into upper trunk with temporal and zygomatic branches and lower trunk with buccal, marginal mandibular, and cervical branches.

Figure 3.3 (a) Surgical landmarks for identifying the location of main trunk of the facial nerve and the temporal-facial division during temporomandibular arthroplastic dissection. (b) Note the variability at the point where the upper trunk of the facial nerve crosses the zygomatic arch deep to the temporoparietal fascial. The nerve can cross the zygomatic arch from 0.8 to 3.5 cm anterior to the bony auditory canal. Consequently, the plane of dissection must be deep to the temporoparietal fascial as the tissues are retracted anteriorly to gain access to the joint capsule.

Figure 3.4 Note that the inferior extent of the incision is the soft tissue attachment of the lobule of the ear. Also, the superior arm of the incision can be extended into the temporal hairline at a 45° angle if greater retraction of the surgical flap is necessary.

Figure 3.5 Depiction of the auriculotemporal nerve emerging from the third division of the trigeminal nerve coursing behind the neck of the condyle. The nerve innervates the majority of the capsule and meniscal-attachment tissues. The capsule is also innervated by the masseteric and posterior deep temporal nerves.

Figure 3.6 Base of skull showing position of foramen ovale in relation to the mandibular fossa. The main trunk of the facial nerve would rarely be encountered during the open joint surgery.

Figure 3.7 Superficial temporal artery and vein, which run just below the subcutaneous tissue anterior to the tragal cartilage.

Figure 3.8 Detailed view of the maxillary artery and its branches. The middle meningeal artery courses medially from the maxillary artery, and the masseteric artery runs laterally through the sigmoid notch. Both the maxillary and masseteric arteries can be damaged during extensive dissection.

Figure 3.9 View from medial aspect of the mandible. Note proximity of middle meningeal, external maxillary, and masseteric arteries. Care should be taken to protect these structures at the level of the condylar neck and sigmoid notch during osteotomies.

Figure 3.10 (a) Isolation of the external carotid artery. (b) Note confirmation of branches off the external carotid artery to distinguish it from the internal carotid artery. (c) Hypoglossal nerve overlying the carotid sheath (black arrow).

Figure 3.11 Angiogram showing branches of the external carotid artery with prominent facial and internal maxillary branches.

Figure 3.12 Placement of endaural and preauricular incisions. Note the optional temporal extension (Al-Kayat and Bramley modification) for more anterior flap retraction.

Figure 3.13 (a) Placement of modified retromandibular approach and endaural incisions. Note well hidden incision placement along the tragus. (b) Comparison of preauricular (thin arrow) and endaural incisions (thick arrow). The endaural incision allows for stepped tissue dissection for improved tissue coverage of the temporomandibular joint.

Figure 3.14 Postauricular approach to the temporomandibular joint.

Figure 3.15 Postauricular approach to the temporomandibular joint. The incision has been made through skin and subcutaneous tissue. The external auditory canal has been completely transected. A purse-string sutre has been placed into the transected external auditory canal to prevent hemorrhage into the canal. Although this approach provides excellent visibility, the closure of the external canal can be problematic and auricular stenosis can occur.

Figure 3.16 (a) Combination of parotidectomy and extended preauricular incision with temporal extension. (b) Auditory alarm connected to terminal branches of the facial nerve. (c) Incision following closure with Jackson–Pratt drain in place.

Figure 3.17 Relative position of the superficial temporal artery and vein and the temporal branch of the facial nerve. The vessels are superior to the superficial temporal fascia and the nerve is deep to the fascia.

Figure 3.18 (a) Facial nerve monitoring used to identify the frontal and zygomatic branches of the facial nerve. This device is not routinely used for surgical approaches to the temporomandibular joint. It is often useful when the normal anatomic position of the nerve has been altered secondary to pathology or scarring from previous surgeries. (b) An auditory alarm. The electrodes are placed into the monitor and are the terminal branches of the facial nerve. (c) Any direct pressure during surgery will result in an auditory alarm warning the surgeon of their proximity to the facial nerve.

Figure 3.19 (a) Endaural approach showing retraction of the skin flap and dissection down to the zygomatic arch. (b) Retraction of the skin flap showing the tragal cartilage.

Figure 3.20 (a) Comparison of endaural and preauricular approaches. Note position of thumb used to retract the tragus during the endaural incision. (b) Dissection of the skin flap from the tragus during the endaural approach. A small amount of tissue/fat should be left covering the tragal cartilage.

Figure 3.21 (a) Retraction of skin flap. (b) Incision through temporoparietal fascial and temporal periosteum.

Figure 3.22 (a and b) Careful dissection of fascia and periosteum from the zygomatic arch exposing the joint capsule.

Figure 3.23 (a and b) Exposure of temporomandibular joint capsule.

Figure 3.24 (a and b) Entry into superior joint space. Blade is angled at 45° to avoid iatrogenic damage to the disk or condylar head.

Figure 3.25 Curved hemostat used to open joint capsule and lyse joint adhesions.

Figure 3.26 Coronal diagram of the fascial layers and facial nerve at the level of the temporoparietal fascial.

Figure 3.27 (a and b) Complete exposure of the temporomandibular joint. Note the careful positioning of the retractor on the zygomatic arch allowing protection of the retracted facial nerve.

Figure 3.28 Well-healed endaural incision. Note the temporal extension within the hair line as well as the position of the tragal incision.

Figure 3.29 Critical anatomic structures encountered during the retromandibular approach to the mandible. Note the position of the facial nerve, and facial artery and vein to the angle of the mandible. The posterior belly of the digastric is deep to the mandible and runs at a 45° angle to the inferior border.

Figure 3.30 Marking of the modified retromandibular incision. Note superior extension on the incision in relation to the lobule of the ear.

Figure 3.31 Diagram demonstrating the relationship of the facial nerve and the artery to the mandible. The facial artery and vein often must be ligated to aid in exposure of the mandible.

Figure 3.32 Retromandibular approach to the mandible. Note submandibular gland (yellow arrow) and posterior belly of the digastric (black arrow).

Figure 3.33 (a) Retromandibular approach to the mandible with masseter exposed. (b) Exposure of mandible following dissection of the masseter. An incision is placed along the pterygomasseteric raphe and great care is taken to dissect the muscle from the mandible in a subperiosteal plane.

Figure 3.34 Exposure of mandible via the retromandibular approach. Note the communication between the endaural and retromandibular incisions.

Figure 3.35 Well-healed endaural and retromandibular incisions following total joint replacement of the temporomandibular joint.

Figure 3.36 Diagram (a) and image (b) showing an intraoral approach to the temporomandibular joint.

Figure 3.37 Patient positioned prior to prepping for an open joint procedure. Note the hair is removed to the level of the helix and 2-in. tape is used to prevent the remaining hair from entering the field.

Figure 3.38 (a) Patient draped prior to prepping. (b) Modified urologic dressing. (c) Urologic dressings allowing sterile manipulation of the mandible, also note Tegaderm covering the nares to limit contamination.

Figure 3.39 Note the cerumen in the external auditory canal, which can often be a source of contamination. A 60 cc syringe with normal saline and Webster cannula are used to irrigate the external auditory canal with antibiotic-impregnated saline. This allows the removal of debris from the ear.

Chapter 04

Figure 4.1 Note the extent of the capsule from both medial (a) and lateral (b) views. On the lateral view, the temporomandibular ligament extends across the inferior insertion of the capsule.

Figure 4.2 (a) Capsule of the right temporomandibular joint. The surgeon can easily palpate the lateral pole of the condyle and superior joint space by feeling for the depression between the glenoid fossa and the condyle. (b) Diagram of the right temporomandibular joint capsule. Note the position of the superior incision (to enter the superior joint space) and inferior incision (to enter the inferior joint space).

Figure 4.3 Series of photos showing incision of the joint capsule and entry into the superior joint space. Note that #15 blade is at angle 45° to avoid injuring the disk. Once the incision is made into the joint capsule, the capsule can further be dissected open with the aid of a curved hemostat.

Figure 4.4 Incision into inferior joint space is made at the neck of the condyle, just above the inferior attachment of the lateral ligament. Once the incision is made, a nasal freer can be used to disk free the disk. Care should be taken to avoid damaging the fibrocartilage covering the condyle.

Figure 4.5 Incision of both superior and inferior joint spaces