Application of endoscope in zygomatic fracture repair

Transcription

1 British Journal ctf Plastic Surgery (2000), 53, 10~ The British Association of Plastic Surgeons DOI: I /bjps BRITISH JOURNAL OF ~ " PLASTIC SURGERY Application of endoscope in zygomatic fracture repair C. T. Chen*, J. R Lai, Y. R. Chen, T. C. Tung, Z. C. Chen* and R. J. Rohrich$ Department of Plastic and Reconstructive Surgery, *Division of Trauma and Emergency Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan, ROC and ~-Department of Plastic and Reconstructive Surgery, The University of Texas; Southwestern Medical Center at Dallas, Texas, USA SUMMARY. The endoscope has been used to visualise the upper face and brow in aesthetic facial surgery which is performed without a coronal incision. We applied these principles to repair zygomatic fractures with the aid of a 4 mm, 30 degree telescope inserted through a small temporal incision. Fracture sites at the zygomatic arch and the zygomaticofrontal suture were exposed and fixed with miniplates under endoscopic control. This technique was used in 15 consecutive patients including 2 with isolated zygomatic arch comminuted fractures and 13 having displaced zygomatic fi'actures with segmental, displaced zygomatic arch fractures. Nine patients were men and six patients were women with a mean age of 35 years. Three patients had associated mandibular fractures. The periods of follow-up ranged from 3 to 22 months. Two patients developed transient frontal nerve palsy which recovered within 2 months. One patient had mild temporal hollowing on the side of the facial fracture. All patients achieved the adequate anatomic reduction and satisfactory malar symmetry. There has been no case of chewing problems, cheek numbness or progressive enophthalmos developing postoperatively. Application of the endoscope in zygomatic fracture repair minimises the scalp scar, avoids forehead numbness, provides a comfortable postoperative recovery and shortens hospital stay. Careful preoperative evaluation and proper surgical technique are mandatory for achieving optimal results in selected patients Harcourt Publishers Ltd Keywords: zygomatic fracture, endoscopic plastic surgery, trauma. Traditionally, orbito-zygomatic fractures are repaired using a combination of supratarsal, subciliary and gingivobuccal incisions. The bicoronal incision is reserved for the comminuted zygomatic fracture especially when it includes comminuted zygomatic arch fractures. In the less severe zygomatic fracture with segmental fractures of the zygomatic arch, surgeons sometimes hesitate to make a bicoronal incision due to the necessity of extended dissection and potential complications associated with its surgical exposure. Recently, the use of the endoscope in plastic surgery has limited the use of incisions for exposure. The endoscope has been used to visualise the zygoma in the subperiosteal facelift without a coronal incision. 14 Previous reports have mentioned endoscopically assisted zygomatic fracture repair] -s but the role of the endoscope is not adequately addressed. We present our experience in the repair of 15 zygomatic fractures with the aid of the endoscope and discuss the role of endoscopy in the management of these fractures. Materials and methods A consecutive series of 15 patients with segmental zygomatic arch fractures, 9 men and 6 women, were selected to receive the endoscopic procedures. If the patients had evidence of enophthalmos, orbital floor blow-out fractures or the necessity of bone graft reconstruction due to severe comminuted zygomatic fractures, they were precluded from the endoscopic repair. The mean age at the time of surgery was 35 years with a range from 19 to 55 years. The cause of injury was either a motorcycle accident (13) or a motor vehicle accident (2). Two patients had isolated comminuted zygomatic arch fractures, while 13 had unilateral, completely displaced zygomatic fractures with comminuted arch fractures. Three patients had associated mandibular fractures. On physical examination, none of these patients had enophthalmos or signs of extraocular muscle entrapment. Preoperative radiographic studies revealed no blow-out fractures of the orbital floor. This precluded the use of the open lower lid incision. A small temporal incision was routinely used in all patients to obtain access to the zygomatic arch and zygomaticofrontal suture, and buccal incision was reserved for the complete zygomatic fracture. Miniplates were applied to the fracture sites of the zygomatic arch in all patients. In 5 of 13 displaced zygomatic fractures, the zygomaticofrontal suture was also fixed with miniplates in addition to the fixation of the maxillary buttress. Surgical technique A small incision located 2-3 cm behind the temporal hairline was made. The incision was deepened into the subgaleal plane and then a 4 ram, 30 degree telescope 100

2 Application of endoscope in zygomatic fracture repair was inserted through the temporal incision to assist in the dissection (Fig. 1A). The dissection proceeded superficial to the deep temporal fascia using a periosteal elevator. The sentinel vein, located on the medial side of the temporoparietal fascia, which was a tributary of the internal maxillary vein, must be carefully coagulated under endoscopic vision to maintain haemostasis and maximise visualisation of the operative field. Once reaching the lateral orbital rim, the periosteum was incised to perform subperiosteal dissection. The fracture line at the zygomaticofrontal suture was encountered (Fig. 1B), and the dissection was carried out inferiorly to expose the zygomatic body and the anterior third of the zygomatic arch. A posterior dissection proceeded below the superficial temporal fascia and inferiorly up to 1 cm above the superior border of the posterior two thirds of the zygomatic arch. At this point, the dissection was deepened below the superficial layer of deep temporal fascia and downward to expose the fracture lines of the zygomatic arch under endoscopic visualisation (Fig. 1C). This subperiosteal dissection at the posterior zygomatic arch was carried forward to connect with the previous anterior dissection, and the whole arch, upper part of the zygomatic body and entire lateral orbital rim were exposed. The inferior portion of the 10l zygomatic body and infraorbital rim were exposed through an upper gingivobuccal incision under direct vision. The displaced zygoma was disimpacted with a Dingman elevator through the oral incision and reduced to the anatomic position. Segmental fractures of the zygomatic arch were reduced using an endoscopic periosteal elevator via the temporal incision with direct endoscopic vision. The adequacy of reduction at the zygomaticofrontal suture was also verified under the supervision of the endoscope. The stability of the zygomatic arch was checked after adequate reduction was ascertained. If the arch was relatively stable, it was first fixed with miniplates. In contrast, the zygomaticofrontal suture was fixed with a miniplate before fixation of the arch if the arch was unstable. To allow for fixation of fracture sites over the zygomatic arch and zygomaticofrontal suture, the miniplates were inserted through the temporal incision and screws were inserted and tightened via a percutaneous trocar under endoscopic visualisation (Fig. 1D), Finally the zygomaticomaxillary fractures were fixed with miniplates because the maxillary buttress presented with comminuted fractures in most of our cases. We did not place any plates over the infraorbital fracture sites. No eyelid incision was created. Figure 1 (A) A 4.0 ram, 30 degreeendoscopeinserted through the temporal incisionto assist in the dissection.(b) Endoscopicviewof the right zygomaticofrontalsuture fracture (black arrow). (C) Endoscopicview of the right zygomaticarch segmental fractures (black arrow). (D) Endoscopicviewshowing a miniplate placed over the zygomaticarch with a drill at the hole of the miniplate.

3 102 British Journal of Plastic Surgery Figure 2 (A) Preoperativephotograph of patient with a left zygomaticfracture. (B) Postoperativeappearance 16 months after endoscopicallyassisted repair with left temporal hollowing. Results The postoperative course was uneventful for all patients. No wound infection or haematoma was noted. The patients were followed up for 3 22 months with an average of 8 months. Two patients developed transient disturbance of the frontal branch of the facial nerve which resolved within 2 months. One patient developed mild hollowing of the temporal region on the side of the facial fracture, which was not perceived by himself (Figs 2A, B). Symmetric malar prominence was achieved (Figs 3A-D) and confirmed by postoperative radiographs in all patients (Figs 3E, F). There were no chewing problems, cheek numbness, enophthalmos or exophthalmos in any patients during the period of the follow-up. Discussion In some cases of zygomatic fracture, especially those involving displacement and telescoping of the zygomatic arch, a transcoronal approach is recommended for exposure and reduction of the zygomatic arch Although the coronal incision allows wide, clear exposure of the zygomatic arch and entire orbit, adequate reduction of fractures and easier plate fixation, it also has some disadvantages. These include potential for increased blood loss, the risk of damage to the frontal branch of the facial nerve, the possibility of bilateral temporal hollowing, permanent forehead and scalp numbness and a scalp scar which may result in alopecia, hypertrophic scarring and chronic scalp pruritus.~4, ~5 With the advent of endoscopy in plastic surgery, the basic principle of wide exposure can still be achieved by inserting a telescope through a small temporal incision. The lateral orbital rim, upper portion of the zygomatic body and the entire zygomatic arch except the orbital wall is clearly visualised under endoscopic magnification. This approaching method certainly brings some advantages over the conventional coronal incision such as minimisation of scar, less intraoperative bleeding and less numbness. The avoidance of a substantial scalp scar is especially beneficial to thin-haired and bald patients. In our study, we also found that the hospital stay was less than similar patients treated with a coronal incision. The reason for this was probably less swelling and pain in the postoperative period. Nonetheless, the endoscopically assisted method possessed several limiting factors such as the training and learning curve necessary to achieve optimal results, the use of new instrumentation, complicated plate fixation as well as the initial increased operation time and the overall investment in the endoscopy instruments. The endoscopic approach to the zygomatic arch carried the same risk of damage to the frontal branch of the facial nerve as the open bicoronal method due to requirement of dissection in the temporal area to expose the zygomatic arch. The incidence of transient frontal weakness in our series was 13.3% (2/15) compatible with the open method in reports of Gruss et al (11.4%) 13 and Stanley (20%), 12 but higher than that in reports of endoscopic methods. In Kobayashi's report, eight patients with zygomatic fractures were treated with endoscopic methods and none developed frontal branch palsy. 5 According to Lee's study in endoscopically assisted zygomatic fracture repair, frontalis function was temporarily impaired in 1 out of 15 patients which returned to normal function within 1 week of surgery. 7 In contrast, when the endoscopic technique was applied in forehead lifting, the incidence of temporary frontal nerve palsy varied from 1.6% to 3%. 16'17

4 Application of endoscope in zygomatic fracture repair 103 Figure 3 (A,B) Preoperative appearance. Left periorbital ecchymosis and malar depression were noted. (C,D) Postoperative appearance 3 months after surgery. Malar symmetry was restored. (E,F) Postoperative computed tomographic scan revealing anatomic reduction of the left zygoma with three points of miniplates fixation.

5 104 British Journal of Plastic Surgery Regarding the dissection plane for approaching the zygomatic arch, the dissection was performed beneath the superficial temporal fascia to the uppermargin of the zygomatic arch, and then the periosteum was incised to proceed with the subperiosteal dissection. This method was the same as that described by Kobayashi et al 5 and Lee et al 6,7 and has been applied to our two patients in whom temporary frontal branch palsy occurred postoperatively. The temporary frontal branch palsy was probably caused by blunt trauma during dissection and manipulation directly under the superficial temporal fascia. Subsequently, we modified the method by performing the dissection beneath the superficial layer of deep temporal fascia which started from 1 cm above the upper margin of the zygomatic arch and then proceeded with the subperiosteal dissection at the upper margin of the zygomatic arch to expose the whole arch. No patient had complications associated with facial nerve palsy when this modified method was used. Gosain et al show in their study of the temporal branch of the facial nerve that the temporal branch of the facial nerve and the superficial temporal artery cross the zygomatic arch in the same anatomic plane. 18 We believe that additional protection of the frontal branch of the facial nerve is provided in this modified method. The principle of this modified method is similar to that of Ramirez's report except that he used an additional lower eyelid incision. 2 There were two different endoscopic access incisions for endoscopic fracture repair of the zygomatic arch. Lee et al 6,7 have described a preauricular incision with scalp extension to approach the zygomatic arch. The intervening segments of the zygomatic arch were dissected free then plated and contoured on a side table. Another transverse lateral orbital incision was created to permit distal plate fixation. Although this had the advantages of easier fracture reduction and plate fixation, it left more noticeable scarring, reducing the benefits of the endoscopic method. Our method was similar to Kobayashi's report s with one incision limited to the temporal scalp for endoscopically assisted reduction. The only facial scar was produced by a puncture wound for drilling and screw placement over the zygomatic arch. This augmented the advantages of the endoscopic procedure with less visible scarring but plate fixation became more difficult. Compared to the four point fixation of displaced zygomatic fractures described by Lee et al, 6,7 the two point (zygomatic arch and maxillary buttress) or three point (zygomatic arch, zygomaticofrontal suture, maxillary buttress) fixation in our series did not produce any further displacement of the zygoma in the followup period. The need to fix the zygomaticofrontal suture depended on the stability of the zygomatic arch after reduction. Hence, preserving continuity of the periosteum over the inferior margin of the zygomatic arch was important during dissection. From our initial experience, we found that the best candidates for endoscopically assisted repair procedures were patients who presented with a displaced zygomatic body and segmental fractures of the zygomatic arch. Isolated displaced, segmental fractures of the zygomatic arch was a relative indication. Endoscopically assisted repair is not appropriate in circumstances such as those requiring exploration of the internal orbit, requirement of a large bone graft reconstruction, and orbital floor blow-out fractures. In conclusion, the endoscope is a useful adjunct for assisting in the visualisation and fixation of the zygomatic arch. Application of the endoscope to assist repair of zygomatic fractures provides several advantages over the conventional methods and avoids the undesirable sequelae of a bicoronal incision. Careful physical examination and especially ophthalmologic examination should be carried out to exclude the possibility of extraocular muscular entrapment and enophthalmos or exophthalmos. The preoperative evaluation of radiographs including computed tomographs is important in ascertaining whether orbital blow-in or blow-out fractures are present. We do not regard the endoscopically assisted method to be a first-line armament in treating zygomatic fractures and we recommend careful selection based on the indications described. References 1. lsse NG. Endoscopic facial rejuvenation: endoforehead, the functional lift. Case reports. Aesthetic Plast Surg 1994; 18: Ramirez OM. Endoscopic techniques in facial rejuvenation: an overview. Part I. Aesthetic Plast Surg 1994; 18: Ramirez OM. Endoscopic full facelift. Aesthetic Plast Surg 1994; 18: Ramirez OM, Pozner JN. Subperiosteal minimally invasive laser endoscopic rhytidectomy: the smile facelift. Aesthetic Plast Surg 1996; 20: Kobayashi S, Sakai Y, Yamada A, Ohmori K. Approaching the zygoma with an endoscope. J Craniofac Surg 1995; 6: Lee CH, Lee C, Trabulsy PR Endoscopic-assisted repair of a malar fracture. Ann Plast Surg 1996; 37: Lee CH, Lee C, Trabulsy PR Alexander JT, Lee K. A cadaveric and clinical evaluation of endoscopically assisted zygomatic fracture repair. Plast Reconstr Surg 1998; 101: 333~ Park DH, Lee JW, Song CH, Han DG, Ahn KY. Endoscopic application in aesthetic and reconstructive facial bone surgery. Plast Reconstr Surg 1998; 102: Jackson IT. Classification and treatment of orbitozygomatic and orbitoethmoid fractures: the place of bone grafting and plate fixation. Clin Plast Surg 1989; 16: Rohrich R J, Hollier LH, Watumull D. Optimizing the management of orbitozygomatic fractures. Clin Plast Surg 1992; 19: i. Stevens MR, Menis MA. Microscrew fixation of zygomatic arch fractures. J Oral Maxillofac Surg 1993; 51: Stanley RB Jr. The zygomatic arch as a guide to reconstruction of comminuted malar fractures. Arch Otolaryngol Head Neck Surg 1989; 115: Gruss JS, Van Wyck L, Phillips JH, Antonyshyn O. The importance of the zygomatic arch in complex midfacial fracture repair and correction of posttraumatic orbitozygomatic deformities. Plast Reconstr Surg 1990; 85: Wojtanowski MH. Bicoronal forehead lift. Aesthetic Plast Surg 1994; 18: Borges AE Unsatisfactory forehead scar following face lift. Plast Reconstr Surg 1986; 78: Chajchir A. Endoscopic subperiosteal tbrehead lift. Aesthetic Plast Surg 1994; 18: Vasconez LO, Core GB, Gamboa-Bobadilla M, Guzman G, Askren C, Yamamoto Y. Endoscopic techniques in coronal brow lifting. Plast Reconstr Surg 1994; 94: Gosain AK, Sewall SR, Yousif NJ. The temporal branch of the facial nerve: how reliably can we predict its path? Plast Reconstr Surg 1997; 99:

6 Application of endoscope in zygomatic fracture repair 105 The Authors Jui-Ping Lai MD, Staff Member Yu-Ray Chen MD, Professor Tung-Chain Tung MD, Assistant Professor Department of Plastic and Reconstructive Surgery Chien-Tzung Chen MD, Assistant Professor Zung-Chung Chen MD, Staff Member Division of Trauma and Emergency Surgery Chang Gung Memorial Hospital Taipei, Taiwan, Republic of China. Rod J. Rohrich MD, FACS, Professor Department of Plastic and Reconstructive Surgery The University of Texas, Southwestern Medical Center at Dallas, Dallas, Texas, USA. Correspondence to Dr Chien-Tzung Chen, Division of Trauma and Emergency Surgery, Chang Gung Memorial Hospital 5, Fu- Hsing Street, Kweishan, Taoyuan, 333, Taiwan, R.O.C. Paper received 15 January 1999, Accepted 10 November 1999.