- Email: [email protected]
Endoscopy-assisted open treatment of condylar fractures of the mandible: extraoral vs intraoral approach
Int. J. Oral Maxillofac. Surg. 2002; 31: 237–243 doi:10.1054/ijom.2001.0213, available online at http://www.idealibrary.com on
Leading Clinical Paper Trauma
Endoscopy-assisted open treatment of condylar fractures of the mandible: extraoral vs intraoral approach
R. Scho¨n, R. Gutwald, A. Schramm, N.-C. Gellrich, R. Schmelzeisen Department of Oral and Maxillofacial Surgery, Albert Ludwigs University, Freiburg i. Br., Germany
R. Scho¨n, R. Gutwald, A. Schramm, N.-C. Gellrich, R. Schmelzeisen: Endoscopy-assisted open treatment of condylar fractures of the mandible: extraoral vs intraoral approach. Int. J. Oral Maxillofac. Surg. 2002; 31: 237–243. 2002 Published by Elsevier Science Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. Abstract. By using an endoscopy assisted extraoral and transoral approach for open reduction of condylar mandible fractures with limited incisions, the risk of facial nerve damage and extensive visible scars can be reduced. The endoscopyassisted treatment of 17 consecutive patients with fractures of the condyle was performed from April 1998 to December 1999. Of the 17 patients, 13 presented with additional mandibular fractures. Nine of the 17 patients were treated by a submandibular approach and eight by a transoral approach. Adequate anatomic reduction was achieved by the submandibular and transoral approach using an endoscopy-assisted technique. The transoral approach proved to be a reliable surgical approach for fractures of the mandibular condyle, even when dislocation with lateral override was present. In four patients, angulated drills and screwdrivers facilitated the transoral treatment of condylar fractures. Transbuccal stab incisions and the use of trochars were not needed in these four patients. The extraoral approach was indicated for severely dislocated fractures such as fractures with medial override or comminution.
Introduction Fractures of the mandibular condyle are common and account for 9–45% of all mandibular fractures1,9,17,18. Closed reduction is the method most widely employed for the treatment of dislocated condylar fractures20. Anatomic reduction is rarely achieved. Rehabilitation and temporomandibular joint (TMJ) function depend on adaptation of the altered condylar morphology. Many techniques have been described for the open treatment of condylar fractures and plate fixation is an established tech0901-5027/02/030237+07 $35.00/0
nique that avoids maxillomandibular fixation3,4,9,10. However, open treatment by preauricular, retromandibular or submandibular approaches may result in injury of the facial nerve or the creation of visible scars22,24. Because of the possible complications, the indications for open reduction or closed treatment remain controversial5,9,11,12. Using an endoscope, superior visibility in areas of limited exposure can be achieved through limited incisions. The risk of facial nerve damage and visible scars can be reduced by such minimally invasive techniques11,12,16.
Key words: condylar fractures; mandible; endoscopy-assisted open treatment. Accepted for publication 18 September 2001
In cases with moderate dislocation, a transoral approach is utilized to avoid damage of the facial nerve and visible scars1,8,16. The indication for the extraoral vs intraoral approach for endoscopyassisted treatment of mandibular condyle fractures is demonstrated. Material and methods In 17 consecutive patients, endoscopyassisted open reduction of condylar fractures of the mandible was performed from April 1998 to December 1999. Out
2002 Published by Elsevier Science Ltd on behalf of the International Association of Oral and Maxillofacial Surgeons.
238
Scho¨n et al. Reduction and fixation
Table 1. Patients and condylar mandible fractures (extraoral, n=9) Patient 1 2 3 4 5 6 7 8 9.
Fracture
Dislocation
Transbuccal
Age
Mand.
Subcondylar Condylar neck Subcondylar Condylar neck Condylar neck Subcondylar Condylar neck Condylar neck bilateral Condylar neck
No Yes Yes No Yes No Yes Yes Yes
Yes Yes Yes Yes Yes Yes Yes Yes Yes
32 30 42 55 33 29 29 41 23
Yes Yes Yes No Yes No Yes Yes Yes
Mand.: additional mandibular fractures. Table 2. Patients and condylar mandible fractures (transoral, n=8) Patient 1 2 3 4 5 6 7 8
Fracture
Dislocation
Transbuccal
Age
Mand.
Condylar neck Subcondylar Condylar neck Subcondylar Condylar neck Subcondylar Subcondylar Subcondylar
Yes No Yes Yes No No No Yes
Yes No Yes No Yes No Yes No
37 33 38 51 29 28 28 25
No Yes Yes Yes Yes No Yes Yes
Mand.: additional mandibular fractures.
of the 17 patients, 13 had additional mandibular fractures (Tables 1 and 2). A total of 12 patients were male and five were female, with an average age of 32 years. The type of fracture, degree of dislocation and result of reduction were evaluated intraoperatively with the endoscope and preoperatively and postoperatively by Townes’ and panoramic radiographs (Figs 1 and 2). The function of the mandible and TMJ were evaluated 6 months after surgery, by measurements of maximal incisal opening, deviation on mouth opening, degree of lateral and protrusive excursion and presence of TMJ clicking and pain. In the extraoral group, the length and aesthetic appearance of the visible scar and the function of the facial nerve were evaluated. Endoscopic equipment
A 30 angle 4 mm diameter endoscope (Karl Storz, Tuttlingen, Germany) and a Xenon light source were used. A suction and irrigation device allowed for irrigation of the endoscope’s tip in the limited optical cavity.
Surgical technique Surgical approach
The ascending ramus of the mandible was approached through a submandibular approach. After incision of the
platysma, the masseter muscle was dissected. Then the periosteum on the ascending mandibular ramus was elevated and the endoscope inserted subperiostally and advanced cranially towards the fracture until the fracture gap became visible in the endoscope. The transoral incisions were similar to the surgical approach for sagittal split osteotomies in orthognathic surgery. The periosteum on the ascending mandibular ramus was elevated down to the mandibular angle and the inferiorly inserting fibres of the temporalis muscle were stripped off the muscular process to create the optical cavity. The endoscope was inserted subperiostally without incision of the masseter muscle and advanced cranially towards the fracture until the fracture gap became visible in the endoscope. Distraction of the TMJ region using reduction forceps at the mandibular angle was performed in the submandibular group. Pressure was put onto the teeth of the mandible in the transoral group to facilitate the repositioning of the condylar fragment. Under endoscopic visualisation the proximal fragment was located. The periosteum and the soft tissues in the vicinity of the condyle were removed carefully to allow for the placement of a 2.0 AO/ASIF non-compression miniplate (DCP Synthes, Paoli, PA, USA) and the insertion of at least two screws on each side of the fracture (Fig. 3).
Prototypes of angled elevators and reduction-manipulation forceps for condylar fractures (Synthes; ADI AO Development Institute, Davos, Switzerland) facilitated the fracture reduction (Fig. 3). Stab incisions in the condylar region were made for the transbuccal insertion of the screws. After repositioning of the condyle, the tip of an elevator was placed on the lateral surface of the condylar fragment to hold the fragment in place while the plate was fixed with the first screw inserted in the proximal fragment. After insertion of the first screw, the fracture reduction was facilitated by pulling the miniplate downwards using modified nerve hooks. The second screw was then inserted adjacent to the fracture in the distal mandibular fragment. After osteosynthesis with two screws, the reduction of the fracture at the posterior border of the ascending ramus was controlled endoscopically. In four patients angulated drills and screwdrivers were used by transoral approach under endoscopic vision to avoid transbuccal stab incisions (Fig. 4). Results An endoscopy-assisted reduction of fractures of the condylar process was performed in 17 patients. The submandibular approach was utilized in nine patients with condylar neck fractures, severely dislocated fractures with medial override and comminuted fractures. The transoral approach was utilized in eight patients with moderately dislocated fractures or lateral override. The nine patients treated by the extraoral approach demonstrated six condylar neck fractures, two subcondylar fractures and two comminuted fractures of the subcondylar region. One patient showed a non-dislocated subcondylar fracture and one patient a severely dislocated bilateral condylar neck fracture (Figs 2 and 3) The eight patients treated by the transoral approach showed three condylar neck fractures and five subcondylar fractures. In the extraoral group, seven out of 11 fractures were dislocated; three consisted of a medial dislocation of the fragment of 90 and two fractures showed a medial override. In the transoral group, two out of eight fractures were dislocated (Tables 1 and 2). One dislocated fracture with a lateral override was treated transorally without transbuccal stab incision (Fig. 1).
Endoscopy-assisted open treatment of condylar fractures of the mandible
239
Fig. 1. Panoramic and Townes’ radiographs preoperatively and postoperatively after endoscopic assisted transoral reduction and fixation of a dislocated condyle fracture with lateral override.
Fig. 2. Radiographs preoperatively and postoperatively after endoscopic assisted reduction and fixation of a severely dislocated bilateral condyle fracture by submandibular approach. Lag screw fixation of the median mandibular fracture was performed in an other clinic before. Note the severe dislocation of the fragments with medial override on the left and medial displacement on the right side.
240
Scho¨n et al.
Fig. 3. Intraoperative view of the dislocated condyle fracture of the same patient as in Fig. 2. (A). The right fragment demonstrated the severe degree of dislocation with medial override. The TMJ is out of the fossa. Intraoperative endoscopic view by a 30 degree angle endoscope before and after osteosynthesis by 2.0 AO/ASIF titanium zygoma miniplate. Note the alignment of the fragments at the posterior aspect of the ascending ramus can be controlled endoscopically. (B) Intraoperative endoscopic view of the left fragment, which was difficult to locate due to the severe dislocation. (C), (D) Intraoperative endoscopic view of the reduction of the left fragment using a prototype of a reduction forceps and an angled elevator (Synthes , Paoli, PA, USA, AO Development Institute, Davos, Switzerland). (E) Lateral view of mandibular condyle region to demonstrate the use of a prototype of an angled elevator (Synthes , Paoli, PA, USA) for the reduction of condylar fractures. Inlet: Angled blade of angled elevator in detail.
Endoscopy-assisted open treatment of condylar fractures of the mandible
Fig. 4. Intraoperative view of angulated drill and screw driver for the drilling and insertion of screws without transbuccal step incision.
In condylar neck fractures, the 2.0 mm zygoma 4- or 5-hole AO-ASIF miniplate (Nos 443.44, 443.45, Synthes) was used. In subcondylar fractures, an additional 2.0 AO-ASIF miniplate (No. 447, Synthes) was used when possible. Fixation of the plate at the condylar fragment and the control of reduction was facilitated by the endoscope. Transbuccal stab incisions for the insertion of the screws were performed in all patients where the submandibular approach was used and in four patients of the transoral group. In four patients in the transoral group angulated drills and screwdrivers were used for the reduction and fixation
of the fractures to avoid incisions for the transbuccal insertion of screws (Fig. 4). In two of these four patients, intraoperatively the type of fracture proved to be more complicated than expected: one fracture was severely dislocated and in one patient a bony fragment of the inferior aspect of the condylar fragment had to be removed. Due to the loss of the fragment and a lamellar fracture, the reduction was challenging. The fracture reduction was controlled endoscopically during the operation and confirmed postoperatively by panoramic and Townes’ radiographs (Figs 1–3, 5).
241
Adequate anatomic reduction was achieved in all patients. The operating time including maxillomandibular fixation was a minimum of 1 h 50 min in a patient with a moderately dislocated fracture treated by a transoral approach and maximum 4 h 40 min in the patient with bilateral medial displaced condylar fractures treated by a bilateral submandibular approach (Figs 2 and 3). The mean operating time was 2 h 50 min for the extraoral and transoral treatment. When additional mandibular fractures were treated, the time for treatment of the additional mandibular fractures was substracted from the total operating time. Immediate postoperative movement was allowed in all but one patient. In this patient, a non-dislocated subcondylar fracture on the left side was managed conservatively by 12 days of maxillomandibular fixation and the comminuted fracture of the ascending ramus on the right side was treated by open reduction (Fig. 5). In two patients, guiding elastics were applied for 5 days, where the occlusion was not secure postoperatively. A soft diet was maintained for 7 days after surgery. After 6 months, the mouth opening in all patients was more than 40 mm without significant deviation. There were no signs of TMJ dysfunction and none of the patients suffered from pain in the TMJ area. Temporary weakness of the mandibular branch of the facial nerve was observed in two patients treated with the submandibular approach postoperatively, but after 6 months there were no signs of facial nerve damage. The length of the submandibular scar was 4–5 cm. The scars were invisible in two patients and aesthetically acceptable in seven patients.
Discussion Closed treatment of dislocated condylar fractures may lead to unsatisfying results and limited function of the TMJ because of shortening of the ascending ramus, producing open bite deformity or malocclusion25. Limited incisal opening, deviation on mouth opening with habitual luxation of the TMJ on the contralateral side may occur due to the deranged condylar morphology and forced adaptation. To avoid these complications, open reduction for adequate anatomic reduction was performed3–5,7, 9,23,24 . The indication for open vs closed
242
Scho¨n et al.
Fig. 5. (A–D) Panoramic and Townes’ radiographs preoperatively and postoperatively after reduction and fixation of a comminuted condyle fracture by submandibular approach. A nondislocated subcondylar fracture on the contralateral side was treated conservatively by Mandibulomaxillary fixation for 12 days (Fig. 5B–D).
reduction of dislocated condylar fractures is controversial in maxillofacial surgery because open reduction may cause damage of the facial nerve and visible scars4,7,21,23,24.
Minimally invasive endoscopic procedures have been described for various indications in the cranio maxillofacial area6,13,15,19. To minimize the risk of the described complications, endoscopy-
assisted techniques using limited or transoral incisions were developed1,8,11,12,16. Anatomic reduction and postoperative function were satisfactory in all 17 patients. In all 17 patients, restoration of occlusion and good TMJ function were achieved after open treatment of the condylar fractures. There was no incidence of damage to the facial nerve and the scars were aesthetically acceptable. Different approaches for the treatment of dislocated condylar fractures were demonstrated. The surgical approach chosen is determined by the type and location of the fracture. The extraoral approach was chosen for fractures with dislocation and medial override and for comminuted fractures. Superior visibility of the fracture site and easier handling of the instruments for reduction and manipulation of the fragment facilitates the procedure by using a submandibular approach11,12,16. In complicated fractures, such as fractures with dislocation and medial override, the extraoral incision can be extended for better exposure of the fracture site. The transoral approach for the treatment of condylar fractures is not routinely used because the transoral management of condylar fractures can be rather difficult due to limited visibility of the fracture site. Endoscopic techniques overcome this limitation and facilitate the treatment1,8,16. The transoral approach in this pilot study was used for endoscopic treatment of subcondylar fractures and condylar fractures that were not severely dislocated with lateral override. In one patient treated by the transoral approach, a dislocated lamelar fracture was noted intraoperatively. The fracture was fixed transorally without transbuccal stab incisions (Fig. 1). Angulated drills and screwdrivers facilitated the transoral management of condylar fractures without the need for a transbuccal stab incisions16. The transoral approach is less timeconsuming than the submandibular approach. Intraoral scars are invisible and there is no risk of facial nerve damage. However, in severely dislocated and comminuted fractures, the extraoral approach for the endoscopy-assisted treatment of condylar fractures is indicated, especially in fractures with medial override. The transoral approach is a reliable surgical approach for subcondylar or condylar neck fractures, even when dislocation with lateral override is
Endoscopy-assisted open treatment of condylar fractures of the mandible present. In non-dislocated fractures and high fractures of the condylar neck, closed reduction and immobilization by maxillomandibular fixation is the treatment of choice. An intensive training in endoscopic techniques and the handling of the equipment is mandatory before the endoscopy-assisted transoral approach for treatment of condylar fractures is performed. With experience, the operation time of endoscopyassisted procedures can be significantly reduced. Acknowledgments. Besides the authors, the special instruments for the reduction of condylar fractures have been developed together with Hamel R (Synthes Paoli, PA, USA), Buescher P (ADI, AO Development Institute, Davos, Switzerland) and the ENT, Plastic, and oral and maxillofacial surgeons of the Minimal Invasive Subcondylar Group: Baker A (Derbyshire, UK), Buchbinder D (New York, NY, USA), Indresano T (Milwaukee, WI, USA), Kellman RM (Syracruse, NY, USA), Lee C (San Fanzisco, CA, USA), Mueller R (Portland, CR, USA), Schmitz JP (San Antonio, TX, USA), Schubert W (St Paul, MN, USA), Troulis M (Boston, MA, USA), Wagner J (Albuquerque, NM, USA). References 1. C C.-T, L J.-P, T T.-C, C Y.-R. Endoscopically assisted mandibular subcondylar fracture repair. Plast Reconstr Surg 1998: 103: 160–165. 2. D L, K KE, L L. 5 years follow-up on condylar fractures. Int J Oral Maxillofac Surg 1989: 18: 18. 3. E U, G S. Zugschraubenosteosynthese bei Unterkiefergelenkfortsatzfrakturen mit einem neuartigen Osteosynthesebesteck. Zahn Mund Kieferheilk 1981: 69: 485.
4. E, E, III, D J. Rigid fixation of mandibular condyle fractures. Oral Surg Oral Med Oral Pathol 1993: 76: 6. 5. E III E, S P, T GS. Occlusal results after open or closed treatment of fractures of the mandibular condylar process. Int J Oral Maxillofacial Surg 2000: 58(3): 260–268. 6. G HD, S P. Endoscopic repair of frontal sinus fracture: case report. J Cranio maxillofac trauma 1996: 2(4): 52–55. 7. H MB. Condylar fractures: Surgical management. J Oral Maxillofac Surg 1994: 52: 1189. 8. J J, L C, T PP. Endoscopic repair of mandibular subcondylar fracture. Plast Reconstr Surg 1998: 101: 160–165. 9. K W, M WG. Treatment of fractures of the articular process by functional stable osteosynthesis using miniaturized dynamic compression plates. Int J Oral Surg 1978: 7: 256. 10. K C. Axial ‘anchor’ screw (lag screw with biconcave washer) or ‘slantedscrew’ plate for osteosynthesis of fractures of the mandibular condyloid process. J Craniomaxillofac Surg 1992: 20: 348. 11. L G, S R. EndoscopeAssisted Fixation of Mandibular Condylar Process Fractures. J Oral Maxillofac Surg 1999: 57: 36–39. 12. L G, S R, W U. 2. Endoskopgestu¨tzte Fixation von Gelenkfortsatzfrakturen des Unterkiefers. Dt Z Mund-Kiefer-GesichtsChir 1998: 2S: 168–170. 13. L CH, L C, T PP. Endoscopic-assisted repair of a malar fracture. Ann Plast Surg 1996: 37: 178. 14. S K, M HJ. Injuries of the facial skeleton. Mod Trends Plast Surg 1966: 2: 62. 15. S¨ R, G N.-C, S A, S R. Endoskopische Chirurgie im Mund-, Kiefer und Gesichtsbereich-Videodemonstration einer endoskopisch assistierten Versorgung einer dislozierten Jochbeinfraktur. Journal DGPW 2000: 12(21): 12.
243
16. S¨ R, G R., S A, G N.-C, S R. Endoscopic assisted treatment of condylar fractures. Differential indication of the extraoral and intraoral approach. Abstract: The Congress 2000 of the EACMFS, Edinburgh 5–9 September 2000: 28 (Suppl.3), vii: 85.. 17. S¨ R, R SIL, C B. Mandibular fractures in Townsville, Australia. Incidence, etiology and treatment using the 2.0 AO/ASIF Miniplate system. Br J Oral Maxillofac Surg 2001: 39: 145–148. 18. T A, L MA. Transosseous wiring in the treatment of condylar fractures of the mandible. J Maxillofac Surg 1976: 4: 200. 19. V LO, C GB, O B. Endoscopy in plastic surgery: An overview. Clin Plast Surg 1995: 22: 585. 20. W RV. Condylar fractures: Nonsurgical management. J Oral Maxillofac Surg 1994: 52: 1185. 21. W RV. Condylar fractures: Nonsurgical management. J Oral Maxillofac Surg 1994: 52: 1185. 22. W MJ, M P, A O, F R. Facial nerve palsy after mandibular fractures. Ann Plast Surg 1995: 34: 546. 23. W G, B T, K KE, L L. Open reduction of subcondylar fractures. Int J Oral Maxillofac Surg 1996: 25: 107. 24. Z MF, K JN. Indications for open reduction of mandibular condyle fractures. Oral Maxillofac Surg 1983: 41: 89. Address: Ralf Scho¨n MD, DMD Klinik und Poliklinik fu¨r Mund-, Kiefer- und Gesichtschirurgie Albert-Ludwigs-Universita¨t Hugstetterstr. 55 D-79106 Freiburg i. Br. Germany Tel: +49 761 270-4701 Fax: +49 761 270-4900 E-mail: [email protected]
Leading Clinical Paper Trauma
Endoscopy-assisted open treatment of condylar fractures of the mandible: extraoral vs intraoral approach
R. Scho¨n, R. Gutwald, A. Schramm, N.-C. Gellrich, R. Schmelzeisen Department of Oral and Maxillofacial Surgery, Albert Ludwigs University, Freiburg i. Br., Germany
R. Scho¨n, R. Gutwald, A. Schramm, N.-C. Gellrich, R. Schmelzeisen: Endoscopy-assisted open treatment of condylar fractures of the mandible: extraoral vs intraoral approach. Int. J. Oral Maxillofac. Surg. 2002; 31: 237–243. 2002 Published by Elsevier Science Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. Abstract. By using an endoscopy assisted extraoral and transoral approach for open reduction of condylar mandible fractures with limited incisions, the risk of facial nerve damage and extensive visible scars can be reduced. The endoscopyassisted treatment of 17 consecutive patients with fractures of the condyle was performed from April 1998 to December 1999. Of the 17 patients, 13 presented with additional mandibular fractures. Nine of the 17 patients were treated by a submandibular approach and eight by a transoral approach. Adequate anatomic reduction was achieved by the submandibular and transoral approach using an endoscopy-assisted technique. The transoral approach proved to be a reliable surgical approach for fractures of the mandibular condyle, even when dislocation with lateral override was present. In four patients, angulated drills and screwdrivers facilitated the transoral treatment of condylar fractures. Transbuccal stab incisions and the use of trochars were not needed in these four patients. The extraoral approach was indicated for severely dislocated fractures such as fractures with medial override or comminution.
Introduction Fractures of the mandibular condyle are common and account for 9–45% of all mandibular fractures1,9,17,18. Closed reduction is the method most widely employed for the treatment of dislocated condylar fractures20. Anatomic reduction is rarely achieved. Rehabilitation and temporomandibular joint (TMJ) function depend on adaptation of the altered condylar morphology. Many techniques have been described for the open treatment of condylar fractures and plate fixation is an established tech0901-5027/02/030237+07 $35.00/0
nique that avoids maxillomandibular fixation3,4,9,10. However, open treatment by preauricular, retromandibular or submandibular approaches may result in injury of the facial nerve or the creation of visible scars22,24. Because of the possible complications, the indications for open reduction or closed treatment remain controversial5,9,11,12. Using an endoscope, superior visibility in areas of limited exposure can be achieved through limited incisions. The risk of facial nerve damage and visible scars can be reduced by such minimally invasive techniques11,12,16.
Key words: condylar fractures; mandible; endoscopy-assisted open treatment. Accepted for publication 18 September 2001
In cases with moderate dislocation, a transoral approach is utilized to avoid damage of the facial nerve and visible scars1,8,16. The indication for the extraoral vs intraoral approach for endoscopyassisted treatment of mandibular condyle fractures is demonstrated. Material and methods In 17 consecutive patients, endoscopyassisted open reduction of condylar fractures of the mandible was performed from April 1998 to December 1999. Out
2002 Published by Elsevier Science Ltd on behalf of the International Association of Oral and Maxillofacial Surgeons.
238
Scho¨n et al. Reduction and fixation
Table 1. Patients and condylar mandible fractures (extraoral, n=9) Patient 1 2 3 4 5 6 7 8 9.
Fracture
Dislocation
Transbuccal
Age
Mand.
Subcondylar Condylar neck Subcondylar Condylar neck Condylar neck Subcondylar Condylar neck Condylar neck bilateral Condylar neck
No Yes Yes No Yes No Yes Yes Yes
Yes Yes Yes Yes Yes Yes Yes Yes Yes
32 30 42 55 33 29 29 41 23
Yes Yes Yes No Yes No Yes Yes Yes
Mand.: additional mandibular fractures. Table 2. Patients and condylar mandible fractures (transoral, n=8) Patient 1 2 3 4 5 6 7 8
Fracture
Dislocation
Transbuccal
Age
Mand.
Condylar neck Subcondylar Condylar neck Subcondylar Condylar neck Subcondylar Subcondylar Subcondylar
Yes No Yes Yes No No No Yes
Yes No Yes No Yes No Yes No
37 33 38 51 29 28 28 25
No Yes Yes Yes Yes No Yes Yes
Mand.: additional mandibular fractures.
of the 17 patients, 13 had additional mandibular fractures (Tables 1 and 2). A total of 12 patients were male and five were female, with an average age of 32 years. The type of fracture, degree of dislocation and result of reduction were evaluated intraoperatively with the endoscope and preoperatively and postoperatively by Townes’ and panoramic radiographs (Figs 1 and 2). The function of the mandible and TMJ were evaluated 6 months after surgery, by measurements of maximal incisal opening, deviation on mouth opening, degree of lateral and protrusive excursion and presence of TMJ clicking and pain. In the extraoral group, the length and aesthetic appearance of the visible scar and the function of the facial nerve were evaluated. Endoscopic equipment
A 30 angle 4 mm diameter endoscope (Karl Storz, Tuttlingen, Germany) and a Xenon light source were used. A suction and irrigation device allowed for irrigation of the endoscope’s tip in the limited optical cavity.
Surgical technique Surgical approach
The ascending ramus of the mandible was approached through a submandibular approach. After incision of the
platysma, the masseter muscle was dissected. Then the periosteum on the ascending mandibular ramus was elevated and the endoscope inserted subperiostally and advanced cranially towards the fracture until the fracture gap became visible in the endoscope. The transoral incisions were similar to the surgical approach for sagittal split osteotomies in orthognathic surgery. The periosteum on the ascending mandibular ramus was elevated down to the mandibular angle and the inferiorly inserting fibres of the temporalis muscle were stripped off the muscular process to create the optical cavity. The endoscope was inserted subperiostally without incision of the masseter muscle and advanced cranially towards the fracture until the fracture gap became visible in the endoscope. Distraction of the TMJ region using reduction forceps at the mandibular angle was performed in the submandibular group. Pressure was put onto the teeth of the mandible in the transoral group to facilitate the repositioning of the condylar fragment. Under endoscopic visualisation the proximal fragment was located. The periosteum and the soft tissues in the vicinity of the condyle were removed carefully to allow for the placement of a 2.0 AO/ASIF non-compression miniplate (DCP Synthes, Paoli, PA, USA) and the insertion of at least two screws on each side of the fracture (Fig. 3).
Prototypes of angled elevators and reduction-manipulation forceps for condylar fractures (Synthes; ADI AO Development Institute, Davos, Switzerland) facilitated the fracture reduction (Fig. 3). Stab incisions in the condylar region were made for the transbuccal insertion of the screws. After repositioning of the condyle, the tip of an elevator was placed on the lateral surface of the condylar fragment to hold the fragment in place while the plate was fixed with the first screw inserted in the proximal fragment. After insertion of the first screw, the fracture reduction was facilitated by pulling the miniplate downwards using modified nerve hooks. The second screw was then inserted adjacent to the fracture in the distal mandibular fragment. After osteosynthesis with two screws, the reduction of the fracture at the posterior border of the ascending ramus was controlled endoscopically. In four patients angulated drills and screwdrivers were used by transoral approach under endoscopic vision to avoid transbuccal stab incisions (Fig. 4). Results An endoscopy-assisted reduction of fractures of the condylar process was performed in 17 patients. The submandibular approach was utilized in nine patients with condylar neck fractures, severely dislocated fractures with medial override and comminuted fractures. The transoral approach was utilized in eight patients with moderately dislocated fractures or lateral override. The nine patients treated by the extraoral approach demonstrated six condylar neck fractures, two subcondylar fractures and two comminuted fractures of the subcondylar region. One patient showed a non-dislocated subcondylar fracture and one patient a severely dislocated bilateral condylar neck fracture (Figs 2 and 3) The eight patients treated by the transoral approach showed three condylar neck fractures and five subcondylar fractures. In the extraoral group, seven out of 11 fractures were dislocated; three consisted of a medial dislocation of the fragment of 90 and two fractures showed a medial override. In the transoral group, two out of eight fractures were dislocated (Tables 1 and 2). One dislocated fracture with a lateral override was treated transorally without transbuccal stab incision (Fig. 1).
Endoscopy-assisted open treatment of condylar fractures of the mandible
239
Fig. 1. Panoramic and Townes’ radiographs preoperatively and postoperatively after endoscopic assisted transoral reduction and fixation of a dislocated condyle fracture with lateral override.
Fig. 2. Radiographs preoperatively and postoperatively after endoscopic assisted reduction and fixation of a severely dislocated bilateral condyle fracture by submandibular approach. Lag screw fixation of the median mandibular fracture was performed in an other clinic before. Note the severe dislocation of the fragments with medial override on the left and medial displacement on the right side.
240
Scho¨n et al.
Fig. 3. Intraoperative view of the dislocated condyle fracture of the same patient as in Fig. 2. (A). The right fragment demonstrated the severe degree of dislocation with medial override. The TMJ is out of the fossa. Intraoperative endoscopic view by a 30 degree angle endoscope before and after osteosynthesis by 2.0 AO/ASIF titanium zygoma miniplate. Note the alignment of the fragments at the posterior aspect of the ascending ramus can be controlled endoscopically. (B) Intraoperative endoscopic view of the left fragment, which was difficult to locate due to the severe dislocation. (C), (D) Intraoperative endoscopic view of the reduction of the left fragment using a prototype of a reduction forceps and an angled elevator (Synthes , Paoli, PA, USA, AO Development Institute, Davos, Switzerland). (E) Lateral view of mandibular condyle region to demonstrate the use of a prototype of an angled elevator (Synthes , Paoli, PA, USA) for the reduction of condylar fractures. Inlet: Angled blade of angled elevator in detail.
Endoscopy-assisted open treatment of condylar fractures of the mandible
Fig. 4. Intraoperative view of angulated drill and screw driver for the drilling and insertion of screws without transbuccal step incision.
In condylar neck fractures, the 2.0 mm zygoma 4- or 5-hole AO-ASIF miniplate (Nos 443.44, 443.45, Synthes) was used. In subcondylar fractures, an additional 2.0 AO-ASIF miniplate (No. 447, Synthes) was used when possible. Fixation of the plate at the condylar fragment and the control of reduction was facilitated by the endoscope. Transbuccal stab incisions for the insertion of the screws were performed in all patients where the submandibular approach was used and in four patients of the transoral group. In four patients in the transoral group angulated drills and screwdrivers were used for the reduction and fixation
of the fractures to avoid incisions for the transbuccal insertion of screws (Fig. 4). In two of these four patients, intraoperatively the type of fracture proved to be more complicated than expected: one fracture was severely dislocated and in one patient a bony fragment of the inferior aspect of the condylar fragment had to be removed. Due to the loss of the fragment and a lamellar fracture, the reduction was challenging. The fracture reduction was controlled endoscopically during the operation and confirmed postoperatively by panoramic and Townes’ radiographs (Figs 1–3, 5).
241
Adequate anatomic reduction was achieved in all patients. The operating time including maxillomandibular fixation was a minimum of 1 h 50 min in a patient with a moderately dislocated fracture treated by a transoral approach and maximum 4 h 40 min in the patient with bilateral medial displaced condylar fractures treated by a bilateral submandibular approach (Figs 2 and 3). The mean operating time was 2 h 50 min for the extraoral and transoral treatment. When additional mandibular fractures were treated, the time for treatment of the additional mandibular fractures was substracted from the total operating time. Immediate postoperative movement was allowed in all but one patient. In this patient, a non-dislocated subcondylar fracture on the left side was managed conservatively by 12 days of maxillomandibular fixation and the comminuted fracture of the ascending ramus on the right side was treated by open reduction (Fig. 5). In two patients, guiding elastics were applied for 5 days, where the occlusion was not secure postoperatively. A soft diet was maintained for 7 days after surgery. After 6 months, the mouth opening in all patients was more than 40 mm without significant deviation. There were no signs of TMJ dysfunction and none of the patients suffered from pain in the TMJ area. Temporary weakness of the mandibular branch of the facial nerve was observed in two patients treated with the submandibular approach postoperatively, but after 6 months there were no signs of facial nerve damage. The length of the submandibular scar was 4–5 cm. The scars were invisible in two patients and aesthetically acceptable in seven patients.
Discussion Closed treatment of dislocated condylar fractures may lead to unsatisfying results and limited function of the TMJ because of shortening of the ascending ramus, producing open bite deformity or malocclusion25. Limited incisal opening, deviation on mouth opening with habitual luxation of the TMJ on the contralateral side may occur due to the deranged condylar morphology and forced adaptation. To avoid these complications, open reduction for adequate anatomic reduction was performed3–5,7, 9,23,24 . The indication for open vs closed
242
Scho¨n et al.
Fig. 5. (A–D) Panoramic and Townes’ radiographs preoperatively and postoperatively after reduction and fixation of a comminuted condyle fracture by submandibular approach. A nondislocated subcondylar fracture on the contralateral side was treated conservatively by Mandibulomaxillary fixation for 12 days (Fig. 5B–D).
reduction of dislocated condylar fractures is controversial in maxillofacial surgery because open reduction may cause damage of the facial nerve and visible scars4,7,21,23,24.
Minimally invasive endoscopic procedures have been described for various indications in the cranio maxillofacial area6,13,15,19. To minimize the risk of the described complications, endoscopy-
assisted techniques using limited or transoral incisions were developed1,8,11,12,16. Anatomic reduction and postoperative function were satisfactory in all 17 patients. In all 17 patients, restoration of occlusion and good TMJ function were achieved after open treatment of the condylar fractures. There was no incidence of damage to the facial nerve and the scars were aesthetically acceptable. Different approaches for the treatment of dislocated condylar fractures were demonstrated. The surgical approach chosen is determined by the type and location of the fracture. The extraoral approach was chosen for fractures with dislocation and medial override and for comminuted fractures. Superior visibility of the fracture site and easier handling of the instruments for reduction and manipulation of the fragment facilitates the procedure by using a submandibular approach11,12,16. In complicated fractures, such as fractures with dislocation and medial override, the extraoral incision can be extended for better exposure of the fracture site. The transoral approach for the treatment of condylar fractures is not routinely used because the transoral management of condylar fractures can be rather difficult due to limited visibility of the fracture site. Endoscopic techniques overcome this limitation and facilitate the treatment1,8,16. The transoral approach in this pilot study was used for endoscopic treatment of subcondylar fractures and condylar fractures that were not severely dislocated with lateral override. In one patient treated by the transoral approach, a dislocated lamelar fracture was noted intraoperatively. The fracture was fixed transorally without transbuccal stab incisions (Fig. 1). Angulated drills and screwdrivers facilitated the transoral management of condylar fractures without the need for a transbuccal stab incisions16. The transoral approach is less timeconsuming than the submandibular approach. Intraoral scars are invisible and there is no risk of facial nerve damage. However, in severely dislocated and comminuted fractures, the extraoral approach for the endoscopy-assisted treatment of condylar fractures is indicated, especially in fractures with medial override. The transoral approach is a reliable surgical approach for subcondylar or condylar neck fractures, even when dislocation with lateral override is
Endoscopy-assisted open treatment of condylar fractures of the mandible present. In non-dislocated fractures and high fractures of the condylar neck, closed reduction and immobilization by maxillomandibular fixation is the treatment of choice. An intensive training in endoscopic techniques and the handling of the equipment is mandatory before the endoscopy-assisted transoral approach for treatment of condylar fractures is performed. With experience, the operation time of endoscopyassisted procedures can be significantly reduced. Acknowledgments. Besides the authors, the special instruments for the reduction of condylar fractures have been developed together with Hamel R (Synthes Paoli, PA, USA), Buescher P (ADI, AO Development Institute, Davos, Switzerland) and the ENT, Plastic, and oral and maxillofacial surgeons of the Minimal Invasive Subcondylar Group: Baker A (Derbyshire, UK), Buchbinder D (New York, NY, USA), Indresano T (Milwaukee, WI, USA), Kellman RM (Syracruse, NY, USA), Lee C (San Fanzisco, CA, USA), Mueller R (Portland, CR, USA), Schmitz JP (San Antonio, TX, USA), Schubert W (St Paul, MN, USA), Troulis M (Boston, MA, USA), Wagner J (Albuquerque, NM, USA). References 1. C C.-T, L J.-P, T T.-C, C Y.-R. Endoscopically assisted mandibular subcondylar fracture repair. Plast Reconstr Surg 1998: 103: 160–165. 2. D L, K KE, L L. 5 years follow-up on condylar fractures. Int J Oral Maxillofac Surg 1989: 18: 18. 3. E U, G S. Zugschraubenosteosynthese bei Unterkiefergelenkfortsatzfrakturen mit einem neuartigen Osteosynthesebesteck. Zahn Mund Kieferheilk 1981: 69: 485.
4. E, E, III, D J. Rigid fixation of mandibular condyle fractures. Oral Surg Oral Med Oral Pathol 1993: 76: 6. 5. E III E, S P, T GS. Occlusal results after open or closed treatment of fractures of the mandibular condylar process. Int J Oral Maxillofacial Surg 2000: 58(3): 260–268. 6. G HD, S P. Endoscopic repair of frontal sinus fracture: case report. J Cranio maxillofac trauma 1996: 2(4): 52–55. 7. H MB. Condylar fractures: Surgical management. J Oral Maxillofac Surg 1994: 52: 1189. 8. J J, L C, T PP. Endoscopic repair of mandibular subcondylar fracture. Plast Reconstr Surg 1998: 101: 160–165. 9. K W, M WG. Treatment of fractures of the articular process by functional stable osteosynthesis using miniaturized dynamic compression plates. Int J Oral Surg 1978: 7: 256. 10. K C. Axial ‘anchor’ screw (lag screw with biconcave washer) or ‘slantedscrew’ plate for osteosynthesis of fractures of the mandibular condyloid process. J Craniomaxillofac Surg 1992: 20: 348. 11. L G, S R. EndoscopeAssisted Fixation of Mandibular Condylar Process Fractures. J Oral Maxillofac Surg 1999: 57: 36–39. 12. L G, S R, W U. 2. Endoskopgestu¨tzte Fixation von Gelenkfortsatzfrakturen des Unterkiefers. Dt Z Mund-Kiefer-GesichtsChir 1998: 2S: 168–170. 13. L CH, L C, T PP. Endoscopic-assisted repair of a malar fracture. Ann Plast Surg 1996: 37: 178. 14. S K, M HJ. Injuries of the facial skeleton. Mod Trends Plast Surg 1966: 2: 62. 15. S¨ R, G N.-C, S A, S R. Endoskopische Chirurgie im Mund-, Kiefer und Gesichtsbereich-Videodemonstration einer endoskopisch assistierten Versorgung einer dislozierten Jochbeinfraktur. Journal DGPW 2000: 12(21): 12.
243
16. S¨ R, G R., S A, G N.-C, S R. Endoscopic assisted treatment of condylar fractures. Differential indication of the extraoral and intraoral approach. Abstract: The Congress 2000 of the EACMFS, Edinburgh 5–9 September 2000: 28 (Suppl.3), vii: 85.. 17. S¨ R, R SIL, C B. Mandibular fractures in Townsville, Australia. Incidence, etiology and treatment using the 2.0 AO/ASIF Miniplate system. Br J Oral Maxillofac Surg 2001: 39: 145–148. 18. T A, L MA. Transosseous wiring in the treatment of condylar fractures of the mandible. J Maxillofac Surg 1976: 4: 200. 19. V LO, C GB, O B. Endoscopy in plastic surgery: An overview. Clin Plast Surg 1995: 22: 585. 20. W RV. Condylar fractures: Nonsurgical management. J Oral Maxillofac Surg 1994: 52: 1185. 21. W RV. Condylar fractures: Nonsurgical management. J Oral Maxillofac Surg 1994: 52: 1185. 22. W MJ, M P, A O, F R. Facial nerve palsy after mandibular fractures. Ann Plast Surg 1995: 34: 546. 23. W G, B T, K KE, L L. Open reduction of subcondylar fractures. Int J Oral Maxillofac Surg 1996: 25: 107. 24. Z MF, K JN. Indications for open reduction of mandibular condyle fractures. Oral Maxillofac Surg 1983: 41: 89. Address: Ralf Scho¨n MD, DMD Klinik und Poliklinik fu¨r Mund-, Kiefer- und Gesichtschirurgie Albert-Ludwigs-Universita¨t Hugstetterstr. 55 D-79106 Freiburg i. Br. Germany Tel: +49 761 270-4701 Fax: +49 761 270-4900 E-mail: [email protected]