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Reprinted by permission of J Craniofac Surg. 2014; 25(1):166-171.

T ECHNICAL S TRATEGY

Management of Subcondylar Mandible Fractures in the Adult Patient

Berit Hackenberg,* † Cameron Lee, BS, ‡ and E. J. Caterson, MD, PhD,*§

mildly displaced fractures and for the patient with multiple injuries who cannot tolerate closed reduction. Key Words: Subcondylar mandible fracture, open reduction, maxillomandibular fixation, endoscopic, treatment algorithm ( J Craniofac Surg 2014;25: 166 – 171) I n the polytrauma patient, facial fractures are commonly seen, with 12% to 56% of cases involving the mandible. 1,2 The ascending or vertical component of the mandible is especially vulnerable, and approximately 30% of all mandible fractures are confined to that area. 3 Despite this frequency of occurrence, management of these patients is controversial and treatment is variable. 4 – 7 Anatomically, the subcondylar region is the distal aspect of the condylar process. It is superiorly bound by the sigmoid notch line and anteriorly bound by an oblique line joining the sigmoid notch and the masseteric tuberosity 8 (Fig. 1). This region is clini- cally significant because of the presence of the facial nerve and the temporomandibular joint (TMJ), both of which may be func- tionally impaired by the fracture itself or the operative treatment. Different degrees of dislocation, displacement, comminution, and fracture lines depend on the magnitude of force, the point of appli- cation, its transmission, and the patient's occlusal position at the moment of impact. The resulting clinical spectrum challenges the surgeon to use a range of techniques with different risk profiles to achieve outcomes that are both functionally and esthetically pleas- ing. This article aimed to evaluate 3 current management strategies in the adult patient: closed reduction with maxillomandibular fixa- tion (MMF), open reduction with internal fixation (ORIF), and endoscopic-assisted reduction with internal fixation (ERIF). We present our rationale for surgical decision making and attempt to develop an algorithmic approach to subcondylar fractures. This ar- ticle can represent a cohesive methodology to guide complex surgi- cal decision making with the goal of aiding craniofacial surgeons in the selection of approaches for this complex fracture pattern. Many studies published in the previous 2 decades have fo- cused on comparing surgical outcomes between closed reduction and open reduction. 4,5,9 – 16 In 1998, Jacobovicz et al reported the first endoscopic open repair of a complex mandibular injury, and techniques of both endoscopic-assisted and pure endoscopic repairs have been reported in the literature more recently. 17 – 22 Although not as prevalent as the standard open and closed approaches, the endo- scopic approach revives this classic debate by adding yet another vi- able treatment option to the management of subcondylar mandible fractures. The present study highlights our experience treating sub- condylar fractures in light of current surgical techniques and tech- nology. Three management modalities and their indications are discussed: MMF, ORIF, and ERIF. Each treatment option is pres- ented, highlighting its specific strengths and weaknesses along with clinical examples. Finally, we provide a treatment algorithm based on this experience that derives a structural basis for our decision making with regard to clinical and radiographic findings. In

Abstract: The treatment of subcondylar mandible fractures is a topic of debate and can be variable even though these fractures are commonly seen. Historically, the treatment algorithm was between open reduction and closed treatment. Now, recent technical ad- vances regarding the use of the endoscope in the field of craniofa- cial surgery provide additional treatment options. This article aimed to evaluate 3 current management strategies: closed reduction with maxillomandibular fixation, open reduction with internal fixation, and endoscopic-assisted reduction with internal fixation. We present our rationale for surgical decision making and attempt to develop an algorithmic approach to subcondylar fractures. Ankylosis of the temporomandibular joint is a feared compli- cation in these fractures that can lead to the decision to apply maxillomandibular fixation for potentially too short of a period. It is the condylar head fractures within the joint's capsule that con- tain the hemarthrosis that are often responsible for ankylosis. Sub- condylar fractures are, by definition, below the attachment of the joint capsule and in general are devoid of ankylosis. Therefore, maxillomandibular fixation is recommended to be applied for a period of 4 to 6 weeks in most cases. Open reduction with internal fixation can increase the risk for facial nerve damage during the op- erative approach. However, open reduction is often necessary in fracture patterns with a high degree of displacement. In these cases, facial nerve monitoring can successfully mitigate risks to allow safe exposure for open reduction with internal fixation of subcondylar fractures. Endoscopic-assisted reduction with internal fixation com- bines the benefits of both techniques while minimizing their associ- ated risks. Nevertheless, reduction can be difficult especially when there is significant medial displacement of the proximal fracture fragment. In our experience, the endoscopic option is optimal for

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From the *Center for Surgery and Public Health, Brigham and Women ’ s Hos- pital, Boston, Massachusetts; † University of Heidelberg Medical School, Heidelberg, Germany; ‡ Harvard School of Dental Medicine, Boston, Massachusetts; and §Division of Plastic Surgery, Brigham and Women ’ s Hospital, Boston, Massachusetts. Received May 14, 2013. Accepted for publication October 28, 2013. Address correspondence and reprint requests to Dr E. J. Caterson, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115; E-mail: ecaterson@partners.org

The authors report no conflicts of interest. Copyright © 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000498

The Journal of Craniofacial Surgery • Volume 25, Number 1, January 2014

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