RESEARCH

ORIGINAL ARTICLE

Changing Trends in the Pattern of Maxillofacial Injuries in Helmeted Motorcycle Accident Patients when Compared to Non-helmeted Motorcycle Accident Patients

K. N. Abhinandan Patel1 • T. R. Sneha1 • Kora Ramya Reddy1 • G. Girish1 •

G. Nikhila1

Received: 20 September 2020 / Accepted: 23 September 2021 / Published online: 6 October 2021

� The Association of Oral and Maxillofacial Surgeons of India 2021

Abstract

Aim Motorcycle accidents are the most predominant type

of road traffic injuries in India. This prospective study

aimed to evaluate the patterns of maxillofacial injuries in

the three types of helmeted and non-helmeted individuals.

Materials and Methods All the patients reporting to the

maxillofacial trauma unit of Sanjay Gandhi hospital with

maxillofacial injuries were considered. The patients were

analyzed for helmet wearing status, type of helmet worn—

full-face, open-face and half-helmet, strap and visor fixa-

tion status, fit of the helmet, ownership of the helmet,

helmet standardization, obeying traffic rules, alcohol con-

sumption status, speed of the vehicle, volume of the

engine, licensure of the driver, hard- and soft-tissue max-

illofacial injuries were recorded.

Results A total of 741 patients participated in the study for

a period of 10 months, majority being males and of a mean

age of 31 years. Most common injuries to the face in the

open- and half-helmet group were lacerations of the chin

and mandibular fractures. Patients who wore ISI standard

full-face helmets with strap and visor fixed experienced

least injuries to the face.

Conclusion This study concluded that out of the three

commonly used helmets, half-helmets provided the least

protection against maxillofacial injuries during a crash,

followed by the open-face helmets. The highest protection

was provided by the full-face helmets with ISI standard-

ization when secured properly with strap and visor.

Keywords Helmet type � Helmet fixation � Maxillofacial

injuries � Motorcycle � Helmet law

Introduction

Of late there is an ascending trend for motorization glob-

ally, which sequentially has increased the number of

injuries and fatalities as a result of road traffic accidents.

Motorized two wheelers account for about 69% of the total

motor vehicles in India [1]. According to the report of

accidental deaths and suicides in India 2019, Karnataka

witnessed a total of 40,666 road traffic accidents and

10,966 deaths in 2019. Among these 38% of them were

two-wheeler riders [2]. Numerous studies have reported

that 20–60% of all the people injured in the road traffic

accidents have had some form of maxillofacial injuries, as

it is the most exposed part of the body [3]. Although not

life threatening, complex maxillofacial trauma results in

poorer health outcomes in terms of nutrition and greater

injury related disability, sometimes even preventing

employment [4]. A helmet consists of (1) a hard shell of

fiberglass or thermoplastic to reduce the force of a direct

blow to the skull, (2) an energy absorbing foam liner to

dissipate deceleration forces and (3) a retention system

consisting of a chinstrap. Use of these helmets at the time

& T. R. Sneha

dr.snehajayanthi@gmail.com

K. N. Abhinandan Patel

abhinandanpatel@yahoo.co.in

Kora Ramya Reddy

kora.ramya@gmail.com

G. Girish

drgirishggowda@gmail.com

G. Nikhila

nikhila28g@gmail.com

1 Department of Faciomaxillary Surgery, Sanjay Gandhi

Institute of Trauma and Orthopedics, Bengaluru, India

123

J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24

https://doi.org/10.1007/s12663-021-01650-w

of accident have shown to reduce the death rate by 42%

when compared to the non-helmeted individuals, whose

risk of facial injuries and death increases by twofold [5, 6].

In 2016 enactment of mandatory helmet law for all types of

motorcycle riders and pillions was enforced by the Kar-

nataka state government. In spite of which 20% of people

do not adhere to the law [7]. Most commonly, three type of

helmets are worn by the riders: full-face, open-face and

half-helmet. The full-face helmets cover the entire head

and have a chin bar that extends upward to a height just

below the lips. The open-face helmets are similar to full

face except that they do not have a chin bar. The half-

helmets cover only the head and may or may not have

visors [8] (Fig. 1). The lack of protection provided by the

open-face and half-helmets explain the high incidence of

facial injuries in spite of wearing a helmet. There are

various other factors which should be considered while

assessing the effectiveness of a helmet. Thus, a detailed

study was conducted with the prospective to evaluate the

effectiveness of the three types of helmet commonly worn

by the riders in protecting the face against injury and to

compare the severity of injuries among the three helmeted

and the non-helmeted groups.

Materials and Methods

This study was conducted in the Department of Facio-

maxillary surgery, Sanjay Gandhi Institute of trauma and

orthopaedics. All the participants were asked to sign a

Outer rigid shell

Chin bar

visor

Impact protection linear

strap

Outer shell

strap

Full face helmet Open face helmet

Half helmet

Fig. 1 Types of helmet

considered in the study

Table 1 Distribution of the

subjects based on motorcycle

engine volume

Motorcycle engine volume Groups Total

Wearing Not wearing

[ 125CC Count 286 161 447

Percent 56.7% 67.9% 60.3%

70-100CC Count 218 76 294

Percent 43.3% 32.1% 39.7%

Total Count 504 237 741

Percent 100.0% 100.0% 100.0%

Chi-square value-8.42

*p value-0.004

J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24 19

123

written informed consent on agreeing to be a part of the

study. A total of 741 patients, who had reported to the

emergency department or the outpatient department of the

hospital from October 2019 to august 2020, participated in

the study. Motorcycle rider or pillion rider involved in a

road traffic accident constituted the sampling frame. The

inclusion criteria was—all motorcyclists (rider/pillion), all

ethnic groups, aged between 18 and 60 years, all types of

maxillofacial injuries involved in the crash. Exclusion

criteria—patients not willing to participate in the study,

patients who were discharged against medical advice, and

who could not answer the questions (either unconscious or

dead). A detailed questionnaire was designed for the col-

lection of data which included patients demographics,

helmet wearing status, type of helmet worn—full-face,

open-face and half-helmet, (Fig. 1) strap and visor fixation

status, fit of the helmet, helmet ownership and standard-

ization, obeying traffic rules, alcohol consumption status,

speed of vehicle, volume of the engine and licensure of the

driver were recorded. Soft-tissue injuries to the face were

recorded by MCFONTZL system developed by Lee et al.

[19], any injuries or fractures to the facial skeleton was

determined by the FISS (Facial injury severity score) score

index which divides the face into three—upper, middle and

lower13. Comparisons were made between the different

helmet wearing groups and also the non-helmeted groups.

Statistical Analysis

Statistical Package for Social Sciences (SPSS) for Win-

dows Version 22.0 Released 2013 (IBM Corp., Armonk,

NY) was used to perform statistical analyses. The Chi-

squared test was used to compare demographic, helmet

types, collision types, and hard- and soft-tissue injuries

with helmet-related characteristics (statistically significant

if p\ 0.05).

Table 2 Comparison of the parameters based on type of helmet using chi-square test

Full face Half Open face Total Chi-square

value

p value

N % N % N % N %

Wearing strap No 66 47.1% 122 48.4 42 37.5% 230 45.6% 6.45 0.16

Yes 74 52.9% 130 51.6 70 62.5% 274 54.4%

Visor No 58 41.4% 142 56.3% 55 49.1% 255 50.6% 8.14 0.017*

Yes 82 58.6% 110 43.7% 57 50.9% 249 49.4%

Helmet fit Good 72 51.4% 174 69.0% 112 100.0% 358 71.0% 72.3 0.00*

Poor 68 48.6% 78 31.0% 0 0.0% 146 29.0%

Helmet fixation during

crash

Displaced but still on

head

59 42.1% 102 40.5% 34 30.4% 195 38.7% 10.87 0.092

Fixed on head 47 33.6% 78 31.0% 34 30.4% 159 31.5%

Had come off 33 23.6% 72 28.6% 44 39.3% 149 29.6%

Driving status Driver 127 90.7% 235 93.3% 93 83.0% 455 90.3% 9.26 0.01*

Pillion rider 13 9.3 17 6.7% 19 17.0% 49 9.7%

Helmet ownership Borrowed 16 11.4% 25 9.9% 20 17.9% 61 12.1% 4.67 0.097

Own 124 88.6% 227 90.1% 92 82.1% 443 87.9%

Following traffic rules No 43 30.7% 68 27.0% 40 35.7% 151 30.0% 2.86 0.23

Yes 97 69.3% 184 73.0% 72 64.3% 353 70.0%

Type of collision Head-on collision 70 50.0% 148 58.7% 63 56.3% 281 55.8% 3.79 0.43

Rear ended 37 26.4% 62 24.6% 26 23.2% 125 24.8%

Single-vehicle crash 33 23.6% 42 16.7% 23 20.5% 98 19.4%

Influence of alcohol Absent 86 61.4% 162 64.3% 83 74.1% 331 65.7% 4.86 0.08

Present 54 38.6% 90 35.7% 29 25.9% 173 34.3%

ISI standard No 57 40.7% 122 48.4% 61 54.5% 240 47.6% 4.84 0.089

Yes 83 59.3% 130 51.6% 51 45.5% 264 52.4%

N number of values in the data

*Statistically significant

20 J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24

123

Results

A total of 741 patients participated in the study, out of

which 237 patients were not wearing any type of helmet

and the rest 504 were wearing any one of the three types

considered in the study. Of these, 140 of them wore a full-

face helmet, 112 of them wore an open-face helmet and

252 of them wore a half-helmet.

In the current study the age group considered was from

18 to 60 years. The mean age of patients in both the groups

was 31.50. Out of the 741, majority were males, i.e., 654

males and 87 females.

Motor vehicle and crash and Helmet particulars. Age

and sex—Table 1.

Maxillofacial injuries.

Helmeted and non-helmeted groups—Table 2.

Association of helmet wearing status with FISS score—

Tab

Soft Tissue

Lacerations were present in 364 (72.2%) patients of the

helmet wearing group and 187 of the not wearing group

(p value 0.052), mostly in the chin followed by cheek,

orbit, lower lip, forehead and upper lip. Contusions were

present in 69 (9.3%) patients of no-helmet group and none

in the helmet group which is statistically significant

(p value-0.00). Abrasions were present in 194 (81.90%)

Table 3 Comparison of the parameters based on status of wearing helmet using chi-square test

Wearing Not wearing Total Chi-square value p value

N % N % N %

Mandible dentoalveolar Absent 478 94.8 224 94.5 702 94.7 0.034 0.85

Present 26 5.2 13 5.5 39 5.3

Body symphysis Absent 212 42.1 90 38 302 40.8 1.11 0.29

Present 292 57.9 147 62 439 59.2

Condyle or coronoid Absent 372 73.8 174 73.4 546 73.7 0.013 0.91

Present 132 26.2 63 26.6 195 26.3

Dentoalveolar midface Absent 502 99.6 196 82.7 698 94.2 84.25 0.00*

Present 2 0.4 41 17.3 43 5.8

Le Fort 1 # Absent 64 12.7 0 0 64 8.6 62.72 0.00*

Present 0 0 15 6.3 15 2

Le Fort 2# Absent 483 95.8 217 91.6 700 94.5 5.62 0.018*

Present 21 4.2 20 8.4 41 5.5

Le Fort 3# Absent 486 96.4 182 76.8 668 90.1 69.98 0.00*

Present 18 3.6 55 23.2 73 9.9

ZMC Absent 500 99.2 216 91.1 716 96.6 32.18 0.00*

Present 4 0.8 21 8.9 25 3.4

Nasal Absent 443 87.9 153 64.6 596 80.4 55.79 0.00*

Present 61 12.1 84 35.4 145 19.6

NOE complex Absent 429 85.1 224 94.5 653 88.1 13.59 0.00*

Present 75 14.9 13 5.5 88 11.9

Upper face—orbital roof Absent 483 95.8 226 95.4 709 95.7 0.08 0.76

Present 21 4.2 11 4.6 32 4.3

Frontal sinus—undisplaced Absent 477 94.6 237 100 714 96.4 13.17 0.00*

Present 27 5.4 0 0 27 3.6

Frontal sinus—displaced Absent 484 96 226 95.4 710 95.8 0.18 0.66

Present 20 4 11 4.6 31 4.2

Combined length of laceration Absent 504 100 237 100 741 100 – –

Present 0 0 0 0 0 0

N number of values in the data

*Statistically significant

J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24 21

123

patients in the no-helmet group and 443 (87.9%) patients of

the helmeted group which is statistically significant

(p value-0.027).

Hard tissue—Table 3.

Subgroups in the helmeted group—Table 4.Association

of helmet wearing status with FISS score - Table 5.

Table 4 Comparison of the fractures based on type of helmet using chi-square test

Full face Half Open face Total Chi-square value p value

N % N % N % N %

FISS Score Score 0 85 60.7% 4 1.6% 4 3.6% 93 18.5% 251.25 0.00*

Score 1 12 8.6% 31 12.3% 23 20.5% 66 13.1%

Score 2 10 7.1% 17 6.7% 9 8.0% 36 7.1%

Score 3 25 17.9% 131 52.0% 60 53.6% 216 42.9%

Score 4 6 4.3% 38 15.1% 12 10.7% 56 11.1%

Score 6 2 1.4% 23 9.1% 4 3.6% 29 5.8%

Score 7 0 0.0% 8 3.2% 0 0.0% 8 1.6%

Mandible dentoalveolar Absent 134 95.7% 234 92.9% 110 98.2% 478 94.8% 4.85 0.08

Present 6 4.3% 18 7.1% 2 1.8% 26 5.2%

Body/symphysis Absent 102 72.9% 87 34.5% 23 20.5% 212 42.1% 81.65 0.00*

Present 38 27.1% 165 65.5% 89 79.5% 292 57.9%

Condyle/coronoid Absent 131 93.6% 174 69.0% 67 59.8% 372 73.8% 42.57 0.00*

Present 9 6.4% 78 31.0% 45 40.2% 132 26.2%

Dentoalveolar midface Absent 138 98.6% 252 100.0% 112 100.0% 502 99.6% 5.22 0.074

Present 2 1.4% 0 0.0% 0 0.0% 2 0.4%

Le Fort 1 Absent 131 93.6% 208 82.5% 101 90.2% 440 87.3% 10.95 0.004*

Present 9 6.4% 44 17.5% 11 9.8% 64 12.7%

Le Fort 2 Absent 139 99.3% 236 93.7% 108 96.4% 483 95.8% 7.28 0.026*

Present 1 0.7% 16 6.3% 4 3.6% 21 4.2%

Le Fort 3 Absent 139 99.3% 235 93.3% 112 100.0% 486 96.4% 14.84 0.001*

Present 1 0.7% 17 6.7% 0 0.0% 18 3.6%

Zygomaticomaxillary fracture (ZMC) Absent 139 99.3% 250 99.2% 111 99.1% 500 99.2% 0.025 0.98

Present 1 0.7% 2 0.8% 1 0.9% 4 0.8%

Nasal Absent 124 88.6% 219 86.9% 100 89.3% 443 87.9% 0.49 0.78

Present 16 11.4% 33 13.1% 12 10.7% 61 12.1%

NOE complex Absent 129 92.1% 204 81.0% 96 85.7% 429 85.1% 8.93 0.011*

Present 11 7.9% 48 19.0% 16 14.3% 75 14.9%

Upper face—orbital roof Absent 136 97.1% 241 95.6% 106 94.6% 483 95.8% 1.02 0.59

Present 4 2.9% 11 4.4% 6 5.4% 21 4.2%

Frontal sinus—undisplaced Absent 136 97.1% 237 94.0% 104 92.9% 477 94.6% 2.6 0.27

Present 4 2.9% 15 6.0% 8 7.1% 27 5.4%

Frontal sinus—displaced Absent 139 99.3% 236 93.7% 109 97.3% 484 96.0% 8.12 0.017*

Present 1 0.7% 16 6.3% 3 2.7% 20 4.0%

Combined length of laceration Absent 140 100.0% 252 100.0% 112 100.0% 504 100.0% – –

Present 0 0.0% 0 0.0% 0 0.0% 0 0.0%

N number of values in the data

*Statistically significant

22 J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24

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Discussion

Traumatic injuries to the maxillofacial region due to road

traffic accidents involving motorcycles are more in devel-

oping countries. Use of helmets decreases the severity of

injury and reduces the health care costs. This prospective

study showed that, not just wearing any helmet, but the

type and its fixation status on the head plays a very

important role in decreasing the severity of injury to the

maxillofacial region. The majority of the patients were

male and the mean age was 31.52 years in both the groups.

This could be due to the fact that male in this age group are

more mobile and are exposed to alcohol and drugs and take

risks. This is in agreement with a study done by

Gopalakrishna et al. who reported a prevalence of max-

illofacial injury in males (89.7%) with a mean age of

28.7 years [9]. The male-to-female ratio in our study was

7.5:1 when compared to 3.5:1 in a study by Oginni et al.

[10]. This study results reveal that the majority of the

patients involved in the crash in both the groups (mean—

60.3%) drove higher engine volume vehicles ([ 125 cc)

which is statistically significant (Table 1) and in consistent

with a study by Mattsson et al. who observed that the risk

of being involved in a fatal crash was higher among the

riders of powerful motorcycles [11]. The majority of the

patients in both the groups were drivers (90%) which is

similar to a study conducted by Mallikarjuna et al. who

reported 75.5% of drivers and 24.3% of pillions [12]. The

pillions sustained less severe injuries. Literature review

indicates that the rider is more prone for injuries due to the

fact that rider will face maximum impact during collision,

due to his more exposed position. Fifty percentage of the

people in the no-helmet group disobeyed the traffic rules

during the time of crash. This was statistically significant.

This is in comparison with a study by Devagappanavar

et al. who reported that 53.30% of the individuals who

repeatedly offended the law, met with a crash [13]. Our

study reported that the highest type of collision seen was

head-on collision which is consistent with a study by Naqvi

et al. who stated that 33% of the fatal crashes were head-on

collisions [14] (Table 2). Seventy-three percentage of the

patients in the no-helmet group were under the influence of

alcohol during the crash, which was statistically significant.

This is in comparison with the meta-analysis conducted by

Nóbrega et al. who states alcohol consumption to be one of

the risk factors for the occurrence of maxillofacial injuries

[15]. There were three types of helmets described in our

study. According to a study done by Yadukul et al., an ISI

standardized helmet is the most effective [16]. As seen in

our study 50% of them were not wearing an ISI stan-

dardized helmet leading to an increased severity of injury.

When the FISS scores of helmet v/s no-helmet group were

compared, the no-helmet group individuals suffered more

severe maxillofacial injuries, which was statistically sig-

nificant (Table 5). We observed that the skeletal and soft-

tissue injuries were more in the half-helmet and open-face

helmet group in comparison with a full-face one. This is

substantiated by a study by Liu et al., who found that full-

face helmets were the most effective in protecting the face

in comparison with the other two [17]. If the helmet strap is

not fastened properly, it can either be displaced/ejected

during the crash thus rendering the helmet useless for

protecting the face. This has be shown distinctly in our

study that non-fastened helmet group had significantly

more injuries (hard and soft) when compared to its coun-

terpart (Table 2). Riders with poor fit helmet sustained

more severe head and facial injuries compared to those

with firmly fixed helmets [18]. Visor is a part of helmet

made out of plastic/polycarbonate which tends to break at

the time of impact, resulting in soft-tissue injuries to the

middle and lower face, especially in the open- and half-

helmets which does not have any lower support or lock. In

the current study, the maximum number of soft-tissue

injuries to the face was seen in the open- and half-helmet

group. Extra-oral abrasions, lacerations and contusions

were more in the no-helmet wearing and the open- and

half-helmet groups when compared to the full helmet

group. Mandibular fractures were more in the half- and

Table 5 Association of helmet wearing status with FISS score

FISS score Helmet wearing status Total

Wearing Not wearing

Score 0 Count 93 0 93

% 0.0% 12.6% 12.6%

Score 1 Count 0 66 66

% 0.0% 8.9% 8.9%

Score 2 Count 26 36 62

% 3.5% 4.9% 8.4%

Score 3 Count 216 76 288

% 9.7% 29.1% 38.9%

Score 4 Count 56 112 168

% 15.1% 7.6% 22.7%

Score 6 Count 16 29 45

% 2.2% 3.9% 6.1%

Score 7 Count 0 8 8

% 0.0% 1.1% 1.1%

Score 10 Count 0 11 11

% 1.5% 0.0% 1.5%

Total Count 237 504 741

% 32.0% 68.0% 100.0%

Chi-square value-204.36

*p value-0.00

J. Maxillofac. Oral Surg. (Jan–Mar 2023) 22(1):18–24 23

123

open-face helmet group (statistically significant p\ 0.001)

due to the fact that there is no chin bar which protects it

like in the full-face helmets (Table 4). The majority of the

midface fractures were observed in the half face helmet

group (17.5%), which is statistically significant. This

endorses the inefficiency of the half-helmets to provide

complete protection to the face.

Conclusion

Though there is a mandatory helmet law for the driver and

the pillion, the number of maxillofacial injuries encoun-

tered are no less. This could be due to poor law enforce-

ment and lack of adequate awareness among the people.

The increase in severity of maxillofacial injuries in the no-

helmet group was highlighted in this study. Out of the three

commonly used helmets, half-helmets provided the least

protection against maxillofacial injuries during a crash

followed by the open-face helmets. The highest protection

was provided by the full-face helmets with ISI standard-

ization when secured accurately with a strap and visor. Our

study also pointed out that improper use of helmet and

disobeying traffic rules affected helmet fixation during a

crash and reduced its effectiveness for preventing max-

illofacial injuries.

Acknowledgements None.

Funding No funds, grants or other support was received.

Declarations

Conflict of interest The authors have no conflicts of interest to

declare that are relevant to the content of this article.

Ethics Approval This study was approved by the institutional review

board and ethics committee.

Consent to Participate Written informed consent was taken from

each participant willing to participate in the study.

Consent for Publication Taken.

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