Management of Mandible Fracture in 150 Children Across 7 Years in a US Tertiary Care Hospital

Key Points

Question

What are the treatment methods and associated complication rates in pediatric mandible fractures managed at a tertiary care center?

Findings

In this cohort study with 150 patients, one-fourth of pediatric mandible fractures were treated without surgery. Most operative pediatric mandible fractures were treated with maxillomandibular fixation alone and a soft diet.

Meaning

This study suggests that conservative management of pediatric mandible fractures using maxillomandibular fixation or observation with a soft diet predominates over open reduction internal fixation with plating.

This cohort study assesses treatment of 150 pediatric patients who presented to a level 2 tertiary care unit between 2010 and 2016 with mandible fracture.

Abstract

Importance

Pediatric mandible fractures are the most common pediatric facial fracture requiring hospitalization, but data are lacking on management methods, outcomes, and complications.

Objective

To analyze management methods, outcomes, and complications of pediatric mandible fractures at an urban academic tertiary care center.

Design, Setting, and Participants

Single-institution cohort study conducted at 2 urban level 1 pediatric trauma centers including all patients aged 0 to 17 years diagnosed with mandible fractures between January 1, 2010, and December 31, 2016. Fractures were treated by multispecialty surgical teams. Data were analyzed between January 1, 2018, and March 1, 2018.

Main Outcomes and Measures

Fracture distributions, mechanisms, treatment methods, complications, and follow-up.

Results

Of 150 patients with 310 total mandible fractures, the mean (SD) age was 12.8 (4.6) years; 108 (72.0%) were male; 107 (71.3%) were white; and 109 (72.7%) had 2 or more mandible fractures. There were 78 condylar or subcondylar fractures (60 patients), 75 ramus or angle fractures (69 patients), 69 body fractures (62 patients), 78 symphyseal or parasymphyseal fractures (76 patients), and 10 coronoid fractures (10 patients). The most common mechanisms of injury were assault and battery, motor vehicle collisions, falls or play, and sports-related mechanisms. Thirty-eight (25%) patients were treated with observation and a soft diet. Children 12 years and older were more likely to receive open reduction internal fixation (ORIF) (P = .02). Of 112 patients treated with surgery, 63 (56.2%) were treated with maxillomandibular fixation (MMF), 24 (21.4%) received ORIF, and 20 (17.9%) received both MMF and ORIF. Nonabsorbable plating was used in all but 1 of the ORIF procedures. Five of 44 (11.4%) patients receiving ORIF or ORIF and MMF had follow-up beyond 6 months, and 8 of the 44 (18.2%) had documented plating hardware removal; hardware was in place for a mean (SD) 180 (167) days. Sixty of the 150 patients (40.0%) had some form of follow-up, a mean (SD) 90 (113) days total after initial presentation. Thirteen patients experienced complications, for a total complication rate of 8.7%.

Conclusions and Relevance

Conservative management, using MMF and a soft diet, was favored for most operative pediatric mandible fractures. Open reduction internal fixation with titanium plating was less commonly used. Outcomes were favorable despite a lack of consistent follow-up.

Level of Evidence

4.

Introduction

Pediatric facial fractures can cause lasting, irreversible impairment in function and cosmesis.¹ Comprising 15% of all facial fractures in the United States, facial fractures occur less frequently in pediatric patients than in adults.² Part of the reason for this disparity is that the pediatric skeleton is more resilient to traumatic forces, owing to its higher elasticity, higher cancellous to cortical bone proportion, and thicker overlying soft tissue and fat.³

Pediatric mandible fractures (PMF) are the most common pediatric facial fracture requiring hospitalization.⁴ The risk of PMF increases with age, in part owing to facial growth. First, the face to cranium ratio increases with age, from 1:8 at birth to 1:2 to 1:2.5 in adulthood.⁵ The mandibular growth in height at the alveolus as well as posterior and superior growth at the condyle ultimately results in translation of the mandible anteriorly and inferiorly.³ This makes the mandible a larger and more accessible structure for trauma with age.

To our knowledge, this study represents the largest single institution cohort study in the United States for pediatric mandible fractures in the literature. The goal of this study was to retrospectively analyze management methods, outcomes, and complications of pediatric mandible fractures at our institution. We hypothesize that owing to favorable biology, the pediatric trauma population has greater osteogenic potential than the adult trauma population. We believe that conservative management, using observation with a soft diet or maxillomandibular fixation (MMF), vs open reduction internal fixation (ORIF) with plating, is favored in most pediatric mandible fractures. Compared with ORIF, MMF confers a decreased risk of long-term facial deformity and is a less extensive surgery with decreased soft tissue trauma; however, it is acknowledged that extended periods of MMF increase the risk of temporomandibular joint ankylosis.

Methods

This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline. We performed a single-institution, retrospective cohort study at 2 level 1 trauma centers. Inclusion criteria were (1) International Classification of Diseases, Ninth Revision (ICD-9) codes 802.xx, or ICD-10 code S02.6XX; (2) aged 0 to 17 years at time of presentation, and (3) occurring between January 1, 2010, and December 31, 2016, and data analysis was conducted from January 1, 2018, to March 1, 2018. At our institution, multiple surgical specialty teams treat pediatric mandible fractures, including otolaryngologists, plastic surgeons, and oral and maxillofacial surgeons. This study was approved by the Indiana University School of Medicine institutional review board. Expedited review was obtained, allowing informed consent to be waived because no intervention was performed and no patient contact occurred while obtaining, reviewing, or analyzing the data.

Data extracted from the electronic medical record included basic demographic characteristics, mechanism(s) of injury, operations, complications, and follow-up. All imaging studies were reviewed. All fractures were categorized according to Association of Osteosynthesis, Craniomaxillofacial Mandible Fracture Classifications.⁶ Statistical analysis was performed using SPSS 22.0 for Windows (IBM Corp) using univariate and multivariate analyses. Two-tailed P < .05 indicated statistical significance.

Results

A total of 150 patients with documented pediatric mandible fractures were evaluated at our institution. The mean (SD) age was 12.8 (4.6) years, and 99 (66%) of the patients were teenagers. One hundred eight (72.0%) patients were male; and 107 (71.3%) were white, which is representative of our patient population. Insurance was most commonly provided by Medicaid (74 patients [49.3%]) and managed care programs (59 patients [39.3%]). One hundred twenty-seven of the patients (84.7%) presented directly to our emergency department vs by transfer from another institution (Table 1).

Table 1. Demographic Features of 150 Pediatric Patients With Mandible Fracture.

Demographic	Patients, No. (%)
Sex
Male	108 (72.0)
Age, y
0-5.99	18 (12.0)
6-11.99	33 (22.0)
12-17.99	99 (66.0)
Race/ethnicity
White	107 (71.3)
African American	34 (22.7)
Hispanic	4 (2.7)
Other/unknown	5 (3.3)
Insurance
Medicaid	74 (49.3)
Managed care	59 (39.3)
Self-pay	8 (5.3)
Commercial	8 (5.3)
Other	1 (0.7)
Encounter type
Routine ED admission	127 (84.7)
Transfer from OSH	23 (15.3)

Abbreviations: ED, emergency department; OSH, outside hospital.

There were 310 total mandible fractures (Table 2), with 109 (72.7%) patients having 2 or more fractures. The distribution of fracture location was evenly split among the 4 major groups of condylar or subcondylar, ramus or angle, body, and symphyseal or parasymphyseal, with each comprising between 22% to 25% of all fractures. Coronoid fractures were encountered in 10 (6.7%) of the 150 patients. The most common fracture combinations were condylar or subcondylar only (3 with bilateral fractures), condylar or subcondylar plus symphyseal or parasymphyseal (10 with bilateral condylar or subcondylar fractures), and angle or ramus plus body.

Table 2. Location of 310 Mandible Fractures .

Fracture Site	No. (%)
	Fractures	Patients
Condyle or subcondyle	78 (25.2)	60 (40.0)
Angle or ramus	75 (24.2)	69 (46.0)
Body	69 (22.3)	62 (41.3)
Symphysis or parasymphysis	78 (25.2)	76 (50.6)
Coronoid	10 (3.2)	10 (6.7)

The most common mechanisms of injury among the 150 patients were assault and battery (33 [22.0%]), motor vehicle collisions (31 [20.7%]), falls or play (22 [14.7%]), and sport-related (22 [14.7%]) (Figure 1). Multivariate analysis showed that condylar or subcondylar fractures were statistically more likely to be caused by falls and play vs other mechanisms (falls vs assault: difference of means, 0.89 [95% CI, 0.15-1.30]; falls vs motor vehicle collision: difference of means, 0.56 [95% CI, 0.15-0.97]; falls vs sport, difference of means, 0.85 [95% CI, 0.41-1.30]; P < .001 for all), angle or ramus fractures more likely caused by assault (assault vs falls: difference in means, 0.37 [95% CI, 0.01-0.84]; P = .03; assault vs motor vehicle collision: difference in means, 0.44 [95% CI, 0.01-0.84]; P = .04), and body fractures more likely caused by sports (sports vs falls: difference in means, 0.42 [95% CI, 0.02-1.15]; P = .04; sports vs motor vehicle collision, 0.72 [95% CI, 0.02-1.15]; P < .001).

Figure 1. Mandible Fracture Mechanisms by Percentage.

ATV indicates all-terrain vehicle.

One hundred thirteen (75.3%) received maxillofacial computed tomography to evaluate the fracture. Thirty-five (23.3%) received only radiography of the mandible, with 2 (1.3%) receiving computed tomography of the cervical spine.

With respect to management, 38 patients (25.3%) were observed and prescribed a soft diet. Univariate analysis showed that patients with an isolated single mandible fracture was statistically more likely to be treated with observation than to undergo operation (P = .007).

Of 112 patients who received operations, 63 (56.2%) received MMF; 24 (21.4%) received ORIF, and 20 (17.9%) received both MMF and ORIF (Figure 2; Table 3). Four patients had closed reduction only, and 1 had open reduction only. Univariate analysis showed that patients with 3 or more fractures were more likely to receive both MMF and ORIF (P = .01). Twenty-four of the 83 patients (28.9%) who underwent MMF, either alone or with ORIF, had documented hardware removal, and hardware was in place for a mean (SD) 31.0 (15.9) days. Nonabsorbable titanium plating was used in all but 1 of the fractures treated with ORIF. Five of 44 (11.4%) patients receiving ORIF or ORIF and MMF had follow-up beyond 6 months. Eight (18.2%) of the patients who received ORIF or ORIF and MMF had documented plating hardware removal, which was in place for a mean (SD) 180 (167) days. Three of the 24 (12.5%) patients who received ORIF only had follow-up beyond 6 months. All 3 patients had hardware removal at a mean (SD) 484 (17) days.

Figure 2. Mandible Fracture Operative Interventions.

MMF inficates maxillomandibular fixation; ORIF, open reduction internal fixation.

Table 3. Repair Method for Pediatric Mandible Fracture by Patient Age.

Repair Method	Age, y
	0 to <6	6 to <12	12 to <18	Total
MMF	5	12	46	63
ORIF	2	3	19	24
MMF+ORIF	0	3	17	20
OBS	11	14	13	38
Other	0	1	4	5
Total	18	33	99	150

Abbreviations: MMF, maxillomandibular fixation; OBS, observation; ORIF, open reduction internal fixation.

With respect to age, ORIF or ORIF with MMF was used with increasing frequency with age by group, with 2 of 18 children younger than 6 years (11.1%), 6 of 33 children 6 to 11.99 years (18.2%), and 36 of 99 children 12 years or older (36.4%) receiving either treatment (Table 1 and Table 3). Conversely, observation followed the opposite trend, with young children younger than 6 years more likely to be observed (χ² = 14.5; P < .001). Of the patients receiving ORIF, 40 (90.9%) were 12 years and older, and these patients were more likely to receive ORIF (χ² = 9.83; P = .002). The most common mechanisms for injury were falls (28%) and motor vehicle collision (21%) in children younger than 6 years, falls (24%) and motor vehicle collision (21%) in children 6 to 11.99 years, and assault and battery (32%) and motor vehicle collision (20%) in children 12 years or older.

Sixty of the 150 patients (40%) had some form of follow-up, a mean (SD) 90 (113) days after initial presentation. Ninety patients (60.0%) had no follow-up after initial presentation.

Complications occurred in 13 patients, for a total documented complication rate of 8.7%. Of these, all patients had 2 or more fractures, and 11 (84.6%) had body fractures. Complications consisted of malunion (2 patients [15.4%]), nonunion (2 patients [15.4%]), deformity (1 patient [7.7%]), infection or abscess (3 patients [23.1%]), hardware extrusion (2 patients [15.4%]), facial numbness (2 patients [15.4%]), and trismus (1 patient [7.7%]). Patients with 3 or more fractures were statistically more likely to have complications (univariate analysis, P = .005). Body fractures were also associated with a higher complication rate (P = .02).

Discussion

The goals of treatment for pediatric mandible fractures are to reestablish normal jaw function, occlusion, and facial symmetry. Management of pediatric mandible fractures has been largely dictated by fracture location and dentition status. For instance, it is generally accepted that pediatric condylar fractures should be managed conservatively, whereas more complex fractures involving the mandibular arch may require internal fixation. In addition, deciduous teeth may not be appropriate for MMF use because they do not provide the tensile strength that cables or arch bars require. Current practice suggests that growth potential of the pediatric mandible is important to consider in the long-term outcome of mandibular fracture management.

In our study, we found that conservative management, specifically observation with a soft diet, or closed reduction with MMF and a soft diet, is favored across 3 different surgical specialties for operative PMFs. Conservative management is often preferred owing to its lower potential for impairing pediatric mandibular growth. Maxillomandibular fixation, in contrast to internal fixation, does not require periosteal dissection, which can disrupt the osteogenic potential of the periosteum and cause scarring that can further restrict growth.⁷ In cases where MMF is used, rigid MMF with use of wiring techniques can be maintained for 2 weeks, depending on surgeon preference and fracture severity, and typically transitions to the use of guiding elastics thereafter.^3,8 The short course of rigid MMF is used to decrease the risk of temporomandibular joint ankylosis. Although the fracture reduction in some instances may be imperfect, children in the primary and mixed dentition stages demonstrate some capacity for spontaneous occlusal realignment after injury and treatment, because primary teeth are shed and permanent teeth erupt.⁷ Guiding elastics, as a healing suggestion, are thought to assist with this occlusal readjustment while the bone remains in a remodeling state. In specific instances, use of arch bars and guiding elastics alone may be sufficient to treat certain fractures.³

Open reduction internal fixation with plating is often indicated in fractures of the mandibular arch or more complex fractures. In our study, ORIF was used nearly as often on its own as it was in conjunction with MMF for more complicated fractures. Nevertheless, the benefits of using ORIF alone center on the ability to not be “wired shut” in MMF, which has its own potential morbidities. These include weight loss, poor hygiene, and psychosocial and communicative difficulties.⁹ Titanium plates have good long-term biocompatibility, provide rigid fixation, and can be easily manipulated intraoperatively to fixate the fracture reduction.³ However, in younger children, the use of titanium plates obliges the surgeon to at least consider the potential risk of facial deformity and asymmetry caused by the plates’ growth restriction on the mandible. In teenaged patients, the risk of facial asymmetry caused by plating should be considered but is less of a concern because the mandible is typically well developed. Most surgeons keep titanium plates in place for 3 to 6 months, with some obtaining confirmation by computed tomography that adequate fracture healing has occurred before any consideration of hardware removal. In cases of ORIF in PMF with titanium plates, the senior author (T.Z.S.) prefers to remove plating approximately 6 months after initial fixation after confirmatory bone healing on computed tomography.

In recent years, the use of resorbable polylactic and polyglycolic acid plates has been introduced into the armamentarium in the treatment of pediatric fractures. In theory, resorbable plates may be ideal for pediatric maxillofacial trauma, because these plates are able to maintain fixation for 4 to 6 weeks during fracture healing, and degradation occurs across 1 to 2 years.³ Therefore, resorption of that plate would theoretically obviate the need for plate removal and reduce or eliminate the growth restriction that titanium plates can cause. In our study, a single patient received resorbable plating with no reported complication or revision surgeries. Further studies may be necessary to determine the safety and efficacy of resorbable plating in pediatric mandible fractures.

In our study, the documented complication rate was low (13 of 150 patients [8.7%]), and this is likely owing in part to the relatively low follow-up rate (60 patients [40.0%]). Our complications, which included malunion and nonunion, hardware extrusion, and infection, were largely correctable and there were no documented cases of postoperative facial weakness. Because this study took place at a tertiary care academic referral center in an urban setting, the likelihood of follow-up may be intrinsically decreased for portions of the patient population. Factors that affect likelihood of follow-up, which are complex and beyond the scope of this paper, include socioeconomic status, insurance type, ease of public transportation, and proximity to the practice.

We found that children 6 years or younger were statistically more likely to be observed, and children older than 12 years were more likely to receive internal fixation of their mandible fractures. Much of this may be attributed to the decreased severity of mandible fractures seen in young children, who have an inherently more resilient facial skeleton for reasons discussed previously. In contrast, we observe that older children who receive plating are likely to keep their hardware without any reports of growth restriction. In the absence of other known complications, this management for mandible fractures is often appropriate given that older children especially in their teenage years will have grown into their adult facial skeleton. Therefore, surgeons should counsel patients and their families that deformity as a product of growth restriction due to plating is a concern, but it may be less applicable in the older, more-developed child. Because healing occurs more rapidly in children, close follow-up is critical to ensuring that any deformity or concerns may be addressed in a timely fashion.

Limitations

There were several limitations with our study. Given the retrospective nature of the study, we were able to assess outcomes only through follow-up visits documented in the electronic medical record. Medical documentation itself has its practitioner-specific deficiencies and may not adequately record specific symptoms that may be related to the mandible fracture repair. Given the poor follow-up, we were unable to assess the true complication rate for all 150 patients. It would be ideal to study these patients in a prospective fashion and follow them in present time to analyze the outcomes of our operations.

Conclusions

Conservative management is favored for most pediatric mandible fractures. In operative cases, maxillomandibular fixation is most commonly used. This approach seeks to decrease the degree of mandibular growth restriction by limiting periosteal dissection, physical strain on the developing bone, and injury to the bone itself. This approach uses the greater osteogenic potential inherent to the pediatric population. Open reduction internal fixation with use of titanium plates was less commonly used compared with absorbable plating. Further studies may be necessary to assess the outcomes of pediatric mandible fracture repair with longer follow-up.