Does a Retromandibular Transparotid Approach for the Open Treatment of Condylar Fractures Result in Facial Nerve Injury?
OBJECTIVE
The retromandibular transparotid approach (RMA) to condylar fractures of the mandible provides excellent access, but can increase the risk of complications. The aim of this study was to estimate the frequency of facial nerve paralysis (FNP) and associated postoperative complications after open reduction and rigid internal fixation (ORIF) of subcondylar fractures through the RMA.


METHODS
This was a retrospective cohort study of patients with condylar fractures requiring ORIF through the RMA. The inclusion criteria were 1) a medical record of surgical treatment of a subcondylar fracture by RMA; 2) preoperative and postoperative radiographs; 3) mental status permitting an adequate neuromotor examination; 4) absence of a post-injury or pretreatment functional facial nerve deficit; and 5) regular postoperative follow-up longer than 6 months with documentation of complications, functional results, and fixation stability. The predictive variables were age, gender, fracture site, fracture pattern, concomitant fractures, etiology, and plate types. The outcome variable was FNP. Univariate, bivariate, and multiple logistic regression statistics were computed.


RESULTS
Fifty patients with 55 displaced mandibular subcondylar fractures (35 men, 15 women; mean age, 44.5 yr; range, 17 to 87 yr) met the inclusion criteria. The condylar fracture involved the neck in 35 patients (63.6%) and the base in 20 patients (36.4%). The fracture pattern was deviation in 11 patients (20.0%), displacement in 23 (41.8%), and dislocation in 21 (38.2%). Precise ORIF with double-buttress fixation resulted in immediate functional recovery in all patients. Seven fractures (12.7%) were associated with FNP that resolved completely within 6 months. Further statistical analysis showed that dislocated and displaced condylar neck fractures were significant risk factors for postoperative FNP (P < .05). Other postoperative complications were minimal.


CONCLUSIONS
The RMA for subcondylar fractures is feasible and safe. Dislocated condylar neck fractures are associated with a highly increased risk of temporary postoperative FNP as a surgical complication.
Associate Professor, Department of Oral and Maxillofacial Surgery, Shimane University Faculty of Medicine, Izumo, Japan; and Attending OMS Surgeon, Division of Oral and Maxillofacial Surgery, Kagawa Prefectural Central Hospital, Takamatsu, Kagawa, Japan. Electronic address: tkanno@med.shimane-u.ac.jp.
Takahiro
T
Kanno
Chief Consultant OMS Surgeon, Division of Oral and Maxillofacial Surgery, Kagawa Prefectural Central Hospital, Takamatsu, Kagawa, Japan.
Shintaro
S
Sukegawa
Formerly Assistant Professor, Department of Oral and Maxillofacial Surgery, Shimane University Faculty of Medicine, Izumo, Japan, and Director, Division of Oral and Maxillofacial Surgery, Oki Hospital, Oki, Shimane, Japan.
Hiroto
H
Tatsumi
Assistant Professor, Department of Oral and Maxillofacial Surgery, Shimane University Faculty of Medicine, Izumo, Japan.
Masaaki
M
Karino
Director and Chair, Division of Oral and Maxillofacial Surgery, Matsue City Hospital, Matsue, Shimane, Japan.
Yoshiki
Y
Nariai
Biostatistician, Translational Research Informatics Center, Foundation of Biomedical Research and Innovation, Kobe, Japan.
Eiji
E
Nakatani
Director and Chair, Division of Oral and Maxillofacial Surgery, Kagawa Prefectural Central Hospital, Takamatsu, Kagawa, Japan.
Yoshihiko
Y
Furuki
Professor and Head, Department of Oral and Maxillofacial Surgery, Shimane University Faculty of Medicine, Izumo, Japan.
Joji
J
Sekine
D000328:Adult; D020220:Facial Nerve Injuries / Q000209:etiology*; D005260:Female; D005593:Fracture Fixation, Internal / Q000379:methods*; D006801:Humans; D008297:Male; D008335:Mandibular Condyle / Q000601:surgery; D008337:Mandibular Fractures / Q000601:surgery*; D008875:Middle Aged; D019647:Oral Surgical Procedures / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology*; D020127:Recovery of Function; D012189:Retrospective Studies