2017-18 HSC Section 3 Green Book

H.-T. Liao et al. / Journal of Cranio-Maxillo-Facial Surgery 43 (2015) 1595 e 1601

(2012) compared the outcome of different approaches and found that there were no signi fi cant differences of functional outcome between the different approaches. This is compatible with our study; we also did not reveal any differences in postoperative function regarding the anatomic reduction, occlusal status and maximal mouth opening between mini-preauricular and other approaches. However, they also reported that only the subman- dibular approach could be used for lower condylar base fractures and reported worse outcomes regarding permanent palsy of the facial nerve and hypertrophic/visible scarring ( Handschel et al., 2012 ). Although a periangular approach provides a better view of the condylar neck than a submandibular incision, the distance from the fracture site is still too great and the risk of marginal mandib- ular branch injury is similar to that of the submandibular incision. Although the intraoral approach offered immediate mouth opening with fewer facial nerve injuries and no visible scar, it was only suitable for condylar base fractures. They concluded that the ret- romandibular transparotid approach provided the best results for condylar neck fractures despite having six temporary and one permanent facial nerve palsies and fi ve hypertrophic scars in 28 patients ( Handschel et al., 2012 ). Short preauricular incisions have been used for a long time in TMJ surgery. However, most studies found that frontal branch palsy or weakness (1 e 32%) was the most common facial nerve injury after TMJ surgery ( do Egito Vasconcelos et al., 2007; Dolwick and Kretzschmar, 1982; Hall et al., 1985; Nellestam and Eriksson, 1997 ). After modi fi cation of the preauricular incision with a tem- poral extension, and with good knowledge of the anatomy of the frontal branch in the soft tissue over the zygomatic arch, the pre- auricular incision became a safe and adequate approach for TMJ surgery ( Al-Kayat and Bramley, 1979 ). Nonetheless, a more forceful downward traction of soft tissue is still needed to access the condylar neck region for adequate reduction and fi xation and this will increase injury to the frontal branch. As such, the retromandibular incision is traditionally the gold standard for management of condylar base or condylar neck frac- tures. However, the level of the retromandibular incision is usually below the fracture site and not directly on it, especially in condylar neck fractures. Large incisions and forceful upward traction are usually inevitable to access the fracture site, reduce the fracture and plate with an internal fi xation system. The forceful upward traction sometimes results in injury of the facial nerve trunk and the large incision will cause an unsightly scar. Facial nerve injury was re- ported in 6 e 19.3% ( Ellis et al., 2000a ). Several modi fi cations of incision were reported to diminish the drawbacks derived from retromandibular incision. Choi and Yoo (1999) used a standard parotidectomy incision which began in the natural skin crease anterior to the tragus, curved around the lobule of the ear, and ran along an upper neck skin crease. They further identi fi ed the trunk of the facial nerve and branch of the facial nerve. They believed the incidence of facial nerve injury would be reduced if you could see the exact facial branch position when dissecting and fi xing the fracture site. However, temporary facial nerve injuries were reported in 20% of the fracture repairs in their study. Tang et al. (2009) described a modi fi ed retro- mandibular incision which is similar to Choi's method. They extended the traditional retromandibular incision upward to the preauricular tragus level with an approach from the anterior edge of parotid gland. Narayanan et al. (2012) presented a similar pre- auricular, tragus to retromandibular incision through the anterior parotid margin and transmasseteric approach for ORIF of condylar fracture. They thought the route could go through the nerve-free window between the buccal and marginal mandibular branch. Salgarelli et al. (2013) also presented a preauricular incision from the tragus and extending to the retromandibular area of the neck.

Fig. 7. Excellent postoperative mouth opening demonstrated at 6-month follow-up of a patient from the mini-preauricular incision group.

4. Discussion

The major issue which restrains surgeons from using open reduction and internal fi xation for condylar process fractures is the danger posed by the complex anatomy around the condylar region. The facial nerve and internal maxillary vessels are in close prox- imity to condylar neck. Hence, the advocates of closed treatment consider that, compared with pre-injury status, acceptable jaw function and aesthetic outcome can be achieved ( Delaire et al., 1975 ). Nonetheless, recent studies found possible chin deviation, facial deformity or malocclusion after closed treatment, especially in patients with fracture displacement or angulation with short- ening of posterior ramus height ( Ellis et al., 2000b; Ellis and Throckmorton, 2000; Palmieri et al., 1999; Schneider et al., 2008; Singh et al., 2010; Throckmorton et al., 2004 ). Besides, successful closed treatment relies on patient compliance and intensive out- patient clinical follow-up. Conversely, successful surgical treat- ment promotes the early recovery of jaw function, maintains a facial pro fi le similar to pre-injury status and reduces the downtime from work. Several approaches were described for surgical management of condylar fractures, including preauricular, retromandibular, transoral, periangular and submandibular incision. Handschel et al.

Fig. 8. The preauricular scar, 6 months postoperatively, in a patient from the mini-preauricular incision group.

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