This study compared different percutaneous surgical approaches for treating condylar fractures to determine their relationship to facial nerve injury (FNI). The study found that approaches involving deep dissection beneath the marginal mandibular nerve branch (submandibular and retroparotid approaches) and the presence of a dislocated fracture were significantly associated with higher risks of FNI. In contrast, approaches involving more superficial dissection above the marginal mandibular nerve branch (transparotid, transmasseteric anteroparotid, high cervical transmasseteric anteroparotid approaches) had lower risks of FNI. The study concluded that superficial group approaches should be recommended to minimize the risk of F

1. Presented by- Dr Dibya Falgoon Sarkar

2. Surgical approaches for condylar fractures
related to facial nerve injury: deep versus
superficial dissection
T. Imai, Y. Fujita, H. Takaoka, T. Kanesaki, Y. Ota, S. Iwai, H. Chisoku, M.
Ohmae, T. Sumi, M. Nakazawa, N. Uzawa
International Journal of Oral & Maxillofacial Surgery
(Issue 48: March 2019; 1227-1234)

3. Introduction
• Success of ORIF of mandibular condylar
fractures depends various factors such as:
1. Surgical approach used
2. Accurate diagnostic imaging
3. Anatomical reduction
4. Osteosynthesis principle used
5. Postoperative physiotherapy
• Most surgeons use percutaneous
approaches for condylar neck and
subcondylar fractures (CN/SCFs).
•Other approaches : Intraoral, endoscopic.

4.  The interbranch space of the facial nerve through which the
surgeons perform the condyle dissection is important.
 Authors have classified the approaches based on whether the
subcutaneous dissection used by approach traverses the
marginal mandibular branch (MMB) system deeply/ superficially:
1. Superficial group: Transparotid, transmasseteric anteroparotid
(TMAP) and high cervical TMAP.
2. Deep group: Submandibular (Risdon) and retroparotid.
Percutaneous approaches for condylar fractures

5. Percutaneous approaches for condylar fractures

6. Background of this article
•Facial nerve injury (FNI) is probably the largest concern for both the
patient and the surgeon after treatment of condylar fractures.
•Few studies have compared the rate of FNI among multiple
percutaneous approaches using statistical methods and multiple
variables.
•Furthermore, most studies comparing postoperative clinical
outcomes of CN/SCFs have only focused on a single approach.
•Recently published systematic reviews have suggested that the
routes i.e. the different surgical pathways of dissection, are more
closely associated with the probability of such injury than the
incision site.
(Al-Moraissi EA, Louvrier A, Colletti G, Wolford LM, Biglioli F, Ragaey M, Meyer C, Ellis E. Does
the surgical approach for treating mandibular condylar fractures affect the rate of seventh
cranial nerve injuries? A systematic review and meta-analysis based on a new classification for
surgical approaches. J Craniomaxillofac Surg 2018;46:398–412. )

7. Aim of this study
To investigate the probability of facial nerve injury in the
treatment of condylar neck and subcondylar fractures with
different percutaneous approaches and to identify factors
predicting facial nerve injury.

8. Subjects & Methods
• Study design- Retrospective cohort study. (Approved by the
institutional review boards of author’s institute)
•Multicentre study- Osaka University Dental Hospital, Saiseikai Senri
Hospital, Toyonaka Municipal Hospital, Rinku General Medical Centre,
Higashiosaka City Medical Centre, and Itami City Hospital.
•Data collection period: January 2010 and August 2018
•The five general hospitals listed are affiliated with Osaka University and
have adopted policies of mutual exchange of surgeons.
• Selection criteria: Patients of > 15 years age with CN/SCFs, who had
undergone surgical treatment with rigid internal fixation by
percutaneous approach, who had pre- and postoperative panoramic
radiographs or computed tomography (CT) images available, who were
mentally capable of undergoing a neuromotor examination, and who
had postoperative clinical follow-up data covering at least 3 months

9. Subjects and methods
 Surgical management:
• The following CN/SCFs have generally been referred for open treatment: (1)
unilateral displaced or dislocated fractures with malocclusion; (2) bilateral
displaced fractures associated with a symphyseal fracture of the mandible or
midface fractures.
• Mainly 5 percutaneous approaches were used: Submandibular, retroparotid,
transparotid, TMAP, high cervical TMAP.
• The condyle was reduced under digital compression on the occlusal aspect of
the ipsilateral lower dentition or by inferior traction using a twisted wire around
the screw that was temporarily inserted into the ramus, if necessary.
•In principle, two miniplates were set in a triangular fashion with one below the
sigmoid notch and the other along the posterior edge of the ramus.
•Postop patients were kept in soft diet for 1 month and advised physiotherapy.

10. Percutaneous approaches:
Superficial versus deep dissection.
Sectional models of percutaneous approaches for condylar neck and subcondylar fractures. The arrows indicate
the dissection routes with the skin incision-to-ramus approach on the right side of the coronal (left panel) and
horizontal sections (right panel). The marginal mandibular branch (MMB) system (stars) is located within the
retracted flap in the deep group approaches (Risdon and RP approaches), but not in the superficial group
approaches (TP, TMAP, and high cervical-TMAP). C, condyle; MM, masseter muscle; P, parotid; R, ramus; RP,
retroparotid; SMAS, superficial musculoaponeurotic system; TMAP, transmasseteric anteroparotid; TP,
transparotid.

11. Subjects and methods
(Study variables)
 Demographic & clinical variables:
1. Age,
2. Gender
3. Cause of trauma
4. Consumption of alcohol before the
accident,
5. Fracture location (condylar neck or
subcondylar)
6. Fracture pattern (non-
displaced/deviated, displaced, or
dislocated)
7. Concomitant mandibular and midfacial
fractures
8. Interval from trauma to the operation
(days)
9. Experience of the operator (a certified
specialist or not certified),
10. Surgical approach used.
11. Type of miniplate for fixation
12. Inter-incisal distance
13. Malocclusion (Grade I, II & III)
14. Postoperative surgical complications.

12. Subjects and methods
(Study variables)
 Primary outcome of this study:
•Occurrence of facial nerve injury (FNI).
• Patients were divided into groups according to FNI presence or
absence at 1 week after surgery. This outcome was also checked at
the postoperative 1-, 3-, and 6-month follow-ups.
•The motor response of the major branches was visually checked,
including the ability to wrinkle the forehead (temporal branch), to
completely close the eyes (zygomatic branches), to puff the cheeks
(buccal branch), and to symmetrically show a smile (marginal
mandibular branch).

13. Subjects and methods
(Statistical analyses)
 Categorical and continuous variables were presented as the
frequency (percentage) and as the mean and standard deviation (or
median (interquartile range), respectively.
 To assess the association with FNI, Fisher’s exact test was applied for
categorical variables and the Wilcoxon rank-sum test for continuous
variables.
 Univariate and multivariate logistic regression models were utilized
to obtain the odds ratios (OR) and 95% confidence intervals (CI) of FNI
occurring and to assess the effects of study variables.
 Additional logistic regression analyses allowing duplication of cases
with bilateral surgeries were performed as sensitivity analyses.
 Software used: R 3.4.1 (R Foundation for Statistical Computing,
Vienna, Austria)

14. Results
A total of 80 patients with 87
fracture sites were eligible for
the analysis
- Unilateral surgery: 73 patients (91.2%)
- Bilateral surgery: 7 patients (8.8%)
- The mean age of the patients was
46.3 years.
Imaging
29%
71%
Out of 87 fractures
Condylar neck Subcondylar

15. Results
15%
42%
43%
Out of 87 fractures
Dislocation
Displacement
Deviation
48
8
0
10
20
30
40
50
60
Exracondylar fracture Midfacial fractures
Out of 80 patients
Out of 80 patients

16. Distribution of surgical
approaches used
54, 62%12, 14%
8, 9%
8, 9%
5, 6%
Out of 87 fractures
Submandibular Retroparotid Transparotid TMAP HC- TMAP

19. Relationship between dislocated fracture and
FNI with stratification by percutaneous
approaches

20. Postoperative complications
other than facial nerve injury
No surgical site infection was evident postoperatively.
 No patients suffered any salivary complications that
required additional intervention or had limited mouth
opening at the 3-month follow-up.
Three patients (3.8%) with concomitant mandibular body
fractures underwent prosthodontic occlusal reconstruction
(grade II malocclusion).
 Plate breakage occurred in one case with a displaced
condylar neck fracture. No patients had hypertrophic skin
scarring.

21. Discussion
 Surgical approaches with dissection deep to marginal mandibular nerve and the
presence of a dislocated fractures were significantly associated with the risk of FNI.
 Reasons:
1. The marginal mandibular branch (MMB) system is located within the retracted
flap in the deep group approaches (Risdon and RP approaches), but not in the
superficial group approaches (TP, TMAP, and high cervical-TMAP).
2. The superficial group surgeries provide more perpendicular access to the
condyle, which facilitates efficient handling and helps reduce the fracture
fragment and stable fixation with plates and thereby decreases the incidence of
FNI.
3. Dissection routes in the superficial group, particularly TMAP and HC-TMAP, pass
through the ‘anatomical nerve-free window’ located superior to the MMB.
4. Unlike zygomatic and buccal branches (70%) the MMB is vulnerable to surgical
injuries due to the low rate of interconnections (17% of cases) leading to the
occurrence of visible postoperative complications.

22. Discussion
Incidence of FNI in:
1. Deep group approaches: 21/66 fractures (31.8%)
2. Superficial group approaches: 1/21 fractures (4.8%)
 High overall incidence of FNI (27.5%) in this study may be due to the
high rate of adopting the deep group approaches (76%) (traditional
submandibular and retroparotid approaches) among the total approaches.
 No FNI was noted with TMAP and high cervical TMAP in this study.
 In the present study, the traditional submandibular approach was the
only procedure that provoked permanent damage (two of 54 fracture sites
treated with this approach, 3.7%).

23. Retraction force necessary to expose the mandibular neck
in Risdon and high cervical anteroparotid transmasseteric
approaches: an anatomic comparative study
Adnot J, Feuss A, Duparc F, Trost O. Surg Radiol Anat 2017;39:1079–84.
•The purpose of this anatomic
study was to compare the
retraction force necessary to
expose the mandibular neck in
the Risdon and the high
cervical anteroparotid
transmasseteric (HAT)
approaches.
Purpose
• An anatomic study was performed
on 18 formalin- embalmed
cadavers. Risdon approach was
done on the left side and HAT
approach on the right side in all
the cases.
• The subjects were placed in a
traction force necessary to
maintain a satisfactory exposure
of the condyle. Force was
measured with amechanical
dynamometer.
Methods
•In the high cervical
anteroparotid approach,
the retraction of the soft
tissues was significantly
lower than in the Risdon
approach.
Conclusion

24. Comparison of various approaches for the treatment of
fractures of the
mandibular condylar process
Handschel J, Ruggeberg T, Depprich R, Schwarz F, Meyer U, Kubler NR, Naujoks C. J Craniomaxillofac Surg
2012;40:e397–401.
Purpose
• The aim of this
investigation was to
compare the
outcome of
different treatment
approaches
regarding function
and surgical side-
effects.
Methods
• 111 fractures of the
mandibular condyle of all
types were included.
• ORIF including the
retromandibular/transpar
otid, submandibular,
preauricular and intraoral
approach were
performed. The clinical
examination included
functional and aesthetic
aspects atleast 1 year
after the fracture.
Conclusion
• Permanent
paralysis of the
facial nerve was
more frequent
with traditional
submandibular
approach (11%)
than with
transparotid
approach (3.6%).

25. Does the surgical approach for treating mandibular condylar fractures
affect the rate of seventh cranial nerve injuries? A systematic review
and meta-analysis based on a new classification for surgical
approaches
Al-Moraissi EA, Louvrier A, Colletti G, Wolford LM, Biglioli F, Ragaey M, Meyer C, Ellis E. J Craniomaxillofac Surg
2018;46:398–412.
• The purpose of this study
was to determine the
rate of facial nerve injury
(FNI) when performing
ORIF of mandibular
condylar fractures by
different surgical
approaches.
Purpose
•A systematic review and meta-
analysis was performed.
•The main outcome variable was
transient facial nerve injury (TFNI)
and permanent facial nerve injury
(PFNI) according to the fracture
levels, namely: condylar head
fractures (CHFs), condylar neck
fractures (CNFs), and condylar base
fractures (CBFs).
• The dependent variables were the
surgical approaches.
Methods
•Safest approach:
•For CHFs, a retroauricular
approach or deep subfascial
preauricular approach
•For CNFs, a TMAP approach with
retromandibular and preauricular
extension.
•For CBFs, high submandibular
incisions with either TMAP
approach with retromandibular or
TM subparotid approach, followed
by intraoral (with or without
endoscopic/transbuccal trocar).
Conclusion

26. Does a retromandibular transparotid approach for the
open treatment of condylar fractures result in facial
nerve injury?
Kanno T, Sukegawa S, Tatsumi H, Karino M, NariaiY, NakataniE, Furuki Y, Sekine J. J Oral Maxillofac Surg
2016;74:2019–32.
Purpose
• The aim of this study
was to estimate the
frequency of facial nerve
paralysis (FNP) and
associated postop
complications following
ORIF of subcondylar
fractures via
retromandibular
approach (RMA).
Methods
•This was a retrospective
cohort study of patients with
condylar fractures requiring
ORIF via RMA.
•The predictive variables
were age, sex, fracture site,
fracture pattern,
concomitant fractures,
etiology, and type of plates.
The outcome variable was
FNP. Univariate, bivariate,
and multiple logistic
regression statistics were
computed.
Conclusion
• 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.

27. Strengths of the study
 It is the only study which compares the clinical outcomes
among multiple percutaneous approaches and has
conducted a multivariate analysis for factors related to facial
nerve injury.
 This multicentre study has tried to reduce surgeon bias by
selecting surgeons with a common background.

28. Limitations of the study
 Retrospective collection of data.
 Multicentre study where surgery was performed by
different surgeons.
 Individual variations, such as the anatomical distribution
of nerve branches or the extensibility and thickness of the
retracted flap, are likely to affect the probability of FNI but
have yet to be evaluated.
 Statistical analysis of prolonged FNI was not performed
due to the small number of samples.

29. Conclusion
 Surgical approaches with dissection deep to marginal
mandibular nerve and the presence of a dislocated fractures
were significantly associated with higher risk of facial nerve
injury.
Percutaneous approaches in the superficial group should
be recommended for the treatment of CN/SCFs to reduce
the risk of FNI.
 Surgeons treating maxillofacial fractures should be aware
of the different subcutaneous dissection routes to the
condyle and choose the most appropriate approach based
on the profile.