Which craniofacial fractures are associated with external auditory canal bleeding?
OBJECTIVE
External auditory canal bleeding (EACB) after facial trauma has been strongly associated with skull base fractures; however, EACB also can occur with other craniofacial fractures. The aim of this study was to analyze the frequency and causes of EACB in different craniofacial fracture types.


METHODS
The investigators used a retrospective cohort study design and enrolled a sample composed of patients with craniofacial fractures evaluated and treated from April 2006 through December 2011. The predictor variable was fracture type, which was categorized into 4 types: skull base fracture, midface fracture, and mandibular fracture with and without involvement of the condyle. The frequency of EACB among fracture types was compared with SPSS 13.0 (SPSS, Inc, Chicago, IL) and χ(2) test. Computed tomographic (CT) scans were analyzed to determine the cause of EACB.


RESULTS
EACB was found in 43 of 573 craniofacial fracture cases, with a frequency of 7.5%. There were 19 EACB sides in 123 skull base fracture cases (15.4%), 26 EACB sides in 150 mandibular fracture cases involving the 196 condyles (13.3%; of these 196 condyles, 92.3% were intracapsular condylar fractures [ICFs]), 2 EACB sides in 150 mandibular fracture cases not involving the condyle (1.3%), and 1 EACB case in 150 midface fracture cases (0.7%). Statistical analysis of EACB frequency for each fracture type showed a significant difference between skull base or mandibular fractures with condylar involvement and midface or mandibular fractures without condylar involvement (P < .05). However, there was no significant difference between skull base and mandibular fractures involving the condyle and midface fracture and mandibular fractures not involving the condyle (P > .05).


CONCLUSIONS
EACB is uncommon in craniofacial fractures. The frequency varies significantly based on fracture type. Skull base fracture and mandibular ICF are the 2 main causes of EACB.
Resident, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Key Laboratory of Stomatology, Shanghai, China.
Chuan
C
Lu
Associate Professor, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Key Laboratory of Stomatology, Shanghai, China. Electronic address: dongmeihe119@yahoo.com.
Dongmei
D
He
Professor, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Key Laboratory of Stomatology, Shanghai, China.
Chi
C
Yang
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004424:Ear Canal / Q000473:pathology*; D005147:Facial Bones / Q000293:injuries*; D005260:Female; D006470:Hemorrhage / Q000209:etiology*; D006801:Humans; D008297:Male; D008335:Mandibular Condyle / Q000293:injuries; D008337:Mandibular Fractures / Q000150:complications; D008440:Maxillary Fractures / Q000150:complications; D008875:Middle Aged; D009295:Nasal Bone / Q000293:injuries; D012189:Retrospective Studies; D019291:Skull Base / Q000293:injuries; D012887:Skull Fractures / Q000150:complications*; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult; D015051:Zygomatic Fractures / Q000150:complications