METHODS
Patients
A database of patients who had undergone closed reduction between March 2013 and June 2015 was reviewed; 313 patients who had isolated nasal bone fractures were included in the study.
Surgical technique
Under general anesthesia, all patients were operated on with closed reduction by the same surgeon. If septal fracture or deviation was existed, we reducted it conservatively using Asch forcep, nasal speculum and No. 3 knife handle wrapped with Vaseline gauze. In order to support the reducted bone fragments, we used Vaseline roll gauze in the dorsal nasal cavity after reduction and Merocel in nasal airways. External nasal thermo-splints were applied [
6].
Assessment methods
The classification of nasal bone fracture by Stranc and Robertson [
7] was used to characterize the fracture type:
Frontal impact group type I (FI): only the lower end of the nasal bones.
Frontal impact group type II (FII): proximal portion of nasal bone & frontal process of maxilla.
Lateral impact group type I (LI): unilateral displacement of nasal bone into the nasal cavity.
Lateral impact group type II (LII): moderate internal displacement of the ipsilateral nasal bone accompanied by some outward displacement of the contralateral nasal bone
Comminuted fracture group (C): multiple segmental fracture with telescoping and depression (
Fig. 1).
For each patient, we tried to use the same axial 1 mm sliced image section of computed tomographic (CT) scans from a dual 128-channel CT SOMATOM Definition Flash (Siemens Industry, Munich, Germany) across the intervals (before and immediate after surgery) to allow, as much as possible, an objective comcomparison of outcomes. Postoperative outcomes were evaluated in the manner listed below (
Table 1) [
8].
Excellent: nasal deviation is absent; arch shape is smooth; no observation of malalignment of the fracture segment.
Good: nasal deviation is absent; arch shape is smooth; malalignment is present, but with either a one-segment irregularity or displacement.
Fair: nasal deviation is absent; arch shape is smooth; malalignment is present, with both bony irregularity and displacement.
Poor: nasal deviation is present; arch shape is not smooth and with two segments of bony irregularity and displacement.
Variables were compared using the chi-square test with Bonferroni correction for multiple comparison (SPSS ver. 19.0, IBM, Armonk, NY, USA). The p-values<0.05 were considered to indicate statistical significance.
DISCUSSION
Postoperative result of nasal bone fracture has been evaluated by complications or patient's satisfaction. However complications and patient's satisfaction are subjective and there is no study about objective outcomes of postoperative result of nasal bone fracture. In this study, we classified postoperative result as 4 grades with immediate postoperative computed tomography, and compared the proportion of excellent results in each fracture type. The proportion of excellent result of FII type (52.00%) were lower than that of FI, LI and LII types (62.67%–66.67%) and the proportion of C type (21.74%) was lower than that of FII type in statistically significant level. This might have been because there was much more displacement and irregularity between fracture segments with the concomitant septal fracture in both FII and C types than in FI and LI types, so the reductions were more complicated. Actually, the prevalence of septal fracture was statistically significantly higher in FII (84.00%) and C (62.79%) types than in FI (53.57%) and LI (37.89%) types.
Despite a relatively higher prevalence of septal fracture in the LII type (90.70%), the proportion of excellent results in the LII type was 62.79%, and it was statistically significantly higher than that of FII and C types. After one month, however, the complication rate of LII type (13.95%) was the highest in all of fracture types.
Moreover, the immediate postoperative result of C type was not good, and the complication rate (13.04%) after one month was higher than the rate of FI, FII, and LI type.
As a result, septal fracture occurred more often in FII, LII, and C types than LI and FI types, and there were lower satisfactory operation results in FII and C type and more complications in LII type. In addition to these result, in the proportion of excellent results by septal fracture, all types except FII showed more excellent results in absence of septal fracture without statistically significant. Therefore, septal fracture can be thought to affect post reduction results in nasal bone fractures.
In this study, FII type showed slightly more excellent results in case with septal fracture (52.38%) than in without septal fracture (50.00%). This might have been because few cases of FII type without septal fracture were existed. So further study might be needed with large size of cases to compare the FII type with septal fracture from the FII type without septal fracture more exactly.
Meanwhile, in the report of Rhee et al. [
9], there are differences between the radiologic findings and the perioperative findings in the degree of septal fracture. In this study, we evaluated the presence of septal fracture by CT scan and perioperative direct examination, and conservative reduction of septal fracture during the nasal reduction was performed. So further evaluation may be needed for evaluating the correlation between the degree of septal fracture and the objective outcomes of the reduction with the data of perioperative findings about the degree of septal fracture.
Postoperative complications of nasal bone fractures—hump nose, saddle nose, hyposmia, and nasal airway obstruction—were observed, and patients were dissatisfied when their noses exhibited deformities that were not noticeable before the injury.
Many studies have reported postoperative complications with nasal bone fractures, and the overall prevalence of complications ranged from 8.4% to 36.4% [
1,
4,
10,
11]. In this study, complications occurred in 26 subjects (8.61%), and this result was matched by the objective outcomes as fair in 18 subjects and poor in 7 subjects, whereas one patient showing a good outcome complained about a hump nose.
Lee et al. [
4] reported complication rates according to fracture type by Stranc classification; in their study, the nasal deformities occurred more in the lateral impact group than in the frontal impact group.
In our study, the prevalence of complication was 8.84% in the lateral group and 6.42% in the frontal group. The most frequent complication in the FI group was saddle nose, and, in the LII and C groups, it was a deviated nose. It is thought that the complications correlate to the direction of injury impact.
In conclusion, it seems that surgical results by fracture type were better in FI, LI, and LII types than in FII and C types with statistical significance. The immediate postoperative result of LII was excellent, but, after one month, more complications occurred than in the other types. Additionally, in each fracture type, complications occurred more often in the group with accompanying septal fracture than in the group without it.