࢖ࢱࣝࢲ࢖ࣥࣇ࢛࣓࣮ࢩࣙࣥ

ITARDA INFORMATION
஺㏻஦ᨾศᯒ࣏࣮ࣞࢺ
lSpeciafeatureNo.97

Wear a helmet to reduce injuries
from cycling accidents

!!

Other
Neck （4 ％ ）Abdomen（4 ％ ）（4 ％ ）

Whole body
（5 ％ ）

Fatal accidents 2009~2011/1,981 people(The composition ratio ofprimary injury sites)

Lower back
（6 ％ ）

Head
（64%）

Chest
（13 ％ ）

 Introduction ࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭
 Casualties resulting from cycling have not fallen
as much as for other accident types࣭࣭࣭࣭࣭࣭࣭࣭࣭
 Following cycling accidents, which parts of the bodyare injured and in what manner? ࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭
 Injuries to which body parts are the most dangerous
for cyclists? ࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭
 Head injuries, which make up most fatalities,
are usually inflicted by four-wheeled vehicles’
exterior body panels and road surfaces ࣭࣭࣭࣭࣭࣭࣭
 What is the situation regarding helmet use? ࣭࣭࣭࣭࣭
 Helmets are essential items
for junior/senior high school students!࣭࣭࣭࣭࣭࣭࣭࣭
 Summary (findings) ࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭࣭
 How to reduce injuries while cycling ࣭࣭࣭࣭࣭࣭࣭࣭

P2
P2
P3
P4
P5
P5
P6
P8
P8

Bicyclehelmet⮬㌿㌴஦ᨾࠉ⿕ᐖ㍍ῶ࡟࣓࣊ࣝࢵࢺ
≉㞟

Wear a helmet to reduce injuries
from cycling accidents !!
 Introduction

In order to reduce cycling accidents (accidents in which bicycles are involved), efforts are being promoted to
expand cycle paths, lanes reserved for cycling (cycling lanes) and cyclist/pedestrian facilities, and to increase
common knowledge of road rules. However, eliminating cycling accidents is no easy task. Therefore, in addition topromoting measures to curb cycling accidents, it is also important to ensure widespread adoption of measures thatwill reduce injuries when accidents do occur. This issue will analyze trends in the number of casualties resulting
from cycling, go on to analyze which parts of the body are injured and which surfaces inflict injury when accidents
occur, and consider measures to reduce injuries.



Casualties resulting from cycling have notfallen as much as for other accident types

10,000
9,000
8,000
7,000
6,000
5,000
4,000
3,000
2,000
1,000
0

Four-wheeled vehicles
Motorcycles
Cyclists

Pedestrians

No. of injuries (1,000 people)

No. of fatalities (people)

These figures show the trends in numbers of fatalities by means of transport (Fig. 1) and trends in numbers of
injuries (Fig. 2), based on the Traffic Accident Database from 2001~2011. Different means of transport are indicatedin different colors. Fatalities and injuries are decreasing year on year for all means of transport. Then, to investigate
how the extent of the decreases in cycling fatalities and injuries compares with the decreases for other means oftransport, we converted the figures to an index taking the 2001 fatalities and injuries as a baseline (=100) (Fig. 3
and Fig. 4). For fatalities, while there has been a striking decrease among four-wheeled vehicle passenger fatalities(Fig. 3), the decrease for cyclists and pedestrians has tended to be less in degree. Turning to numbers of injuries(Fig. 4), while there has been a striking decrease in injuries among motorcyclists, the decrease among cyclists has
been the smallest among all the means of transport.

ʻ01 ʻ02 ʻ03 ʻ04 ʻ05 ʻ06 ʻ07 ʻ08 ʻ09 ʻ10 ʻ11

120.0

Pedestrians

100.0

Cyclists

80.0
60.0

Four-wheeled vehicles

40.0

Motorcycles

1,000
800
600

Four-wheeled vehicles
Motorcycles

400

Cyclists

200
0Pedestrians

ʻ01 ʻ02 ʻ03 ʻ04 ʻ05 ʻ06 ʻ07 ʻ08 ʻ09 ʻ10 ʻ11

Fig. 2: Trends in numbers of injuries,
by means of transport

Year

120.0

Cyclists
100.0
80.0
60.0
40.0

Pedestrians
Motorcycles

Four-wheeled vehicles

20.0

20.0
0.0

1,200

Year

Index for no. of injuries

Index for no. of fatalities

Fig 1: Trends in numbers of fatalities,
by means of transport

1,400

0.0
ʻ01 ʻ02 ʻ03 ʻ04 ʻ05 ʻ06 ʻ07 ʻ08 ʻ09 ʻ10 ʻ11

ʻ01 ʻ02 ʻ03 ʻ04 ʻ05 ʻ06 ʻ07 ʻ08 ʻ09 ʻ10 ʻ11

Fig 3: Trends in numbers of fatalities,
by means of transport

Fig 4: Trends in numbers of injuries,
by means of transport.

Year*Index taking the 2001 ﬁgures as the baseline of 100

Year*Index taking the 2001 ﬁgures as the baseline of 100

Among cyclists, fatalities and injuries have decreased less than among other means of transport
ITARDA INFORMATION no.97

ITARDA INFORMATION no.97



Following cycling accidents,
which parts of the body are injured and in what manner?

Fig. 5 shows the composition ratio of primary injury sites among cyclists, broken down by the degree of injury. Fig. 6 andFig. 7 show the different types of arm and leg injuries, which are both common among slight injuries. Fig. 8 and Fig. 9 show
the different types of head and chest injuries, which make up many fatalities. The results can be summarized as follows.

(1) Most people with slight injuries are injured in the extremities (arms and legs), while head andchest injuries are commonest among fatalities.
(2) Among slight injuries to the extremities, the commonest types are cuts (lacerations), abrasions (crushing, scrapes) and contusions.
(3) Among fatalities, the commonest types of injuries are fractures and lacerations/crushing/
contusions for head injuries, and fractures and rupture of internal organs for chest injuries.
Composition ratio (%)

70
60

Fatalities:
1,981 people
Serious injuries: 33,864 people
Slight injuries: 415,832 people

Fatalities

50

Serious injuries

40
30

Slight injuries
20
10
0
Whole
body

Head

Face

Neck

Chest

Abdomen

Back

Lower
back

Arm

Leg

Other

Fig. 5: Composition ratio of primaryy injuryy sites among cyclists,
cyclistys, byy degree of injury
y (2009~2011)
Composition ratio = (No. of injuries for each primary injury site) / (No. of injuries) x 100

Which parts of the body require protective equipment when cycling?

70

No. of injuries (1,000 people)

No. of injuries (1,000 people)

We used the combined figures for cyclists and passengers from 2009 to 2011 (a three-year period) from the
Traffic Accident Database for the analyses discussed between Section 3 and Section 5.

60
50
40
30
20
10

160
140
120
100
80
60
40
20

0
Fractures

Sprains

Lacerations/
Crushing/
Contusions

0
Other

Types of injuries among injured people
Fig. 6: Types of arm injuries (slight injuries)

Fractures

Sprains

Lacerations/
Crushing/
Contusions

Other

Types of injuries among injured people
Fig. 7: Types of leg injuries (slight injuries)

ITARDA INFORMATION no.97

600

No. of fatalities (people)

No. of fatalities (people)⮬㌿㌴஦ᨾࠉ⿕ᐖ㍍ῶ࡟࣓࣊ࣝࢵࢺ
≉㞟

500
400
300
200

100
90
80
70
60
50
40
30
20

100

10
0

Sprains Lacerations/
Crushing/
Contusions

Fractures Cerebral
damage0
Other

Fractures Cerebral
damageSprains Lacerations/
Crushing/
Contusions

Other

Types of injuries among injured people

Types of injuries among injured people

Fig. 8: Types of head injuries (fatalities)

Fig. 9: Types of chest injuries (fatalities)

Injuries to which body parts are the most dangerous for cyclists?

Fatality rate (%)

Fig. 10 looks at what percentage of all injuries result in fatalities, for each primary injury site [= (No. of fatalities) /No. of casualties) x 100]. The injuries most likely to prove fatal are head injuries (2.2%, 1,265 people), followed byabdominal injuries (1.9%, 84 people) and chest injuries (1.1%, 249 people). The head deserves the most attention
because injuries to this part are the largest contributors to fatality rates and the number of casualties. The absolute
numbers of casualties with abdominal and chest injuries are lower than those with head injuries, but the fatality
rates of abdominal and chest injuries are close to that of head injuries.
2.5
2.0
1.5
1.0
0.5
0

Head

No. offatalities
No. ofserious
injuries
No. ofslightinjuries

Face

Neck

Chest

Abdomen

Back

Lower back

Arm

Leg

Back

Lower
back

Arm

Other

Whole
body

Head

Face

Neck

101

1,265

20

75

249

84

9

110

3

28

37

1,981

0

6,403

1,728

902

4,171

361

388

2,847

6,919

10,1396

33,864049,782

20,377

41,346 18,562

3,958

3,542

38,88077,594 161,627

164

415,832

Chest Abdomen

Leg

Total

（People）

Fig. 10: Fatality rate by primary injury site among cyclists (2009~2011)

When the head, abdomen or chest receives heavy impact,
prompt examination by a doctor is critical.
ITARDA INFORMATION no.97

ITARDA INFORMATION no.97

Head injuries, which make up most fatalities, are usually inflicted by four-wheeled vehicles’ exterior body panels and road surfaces

No. of fatalities (people)

Let us now look at which surfaces are inflicting the injuries investigated in Section 4. Fig. 11 shows the distributionof injury-inflicting surfaces for 1,265 fatalities caused by head injuries. Most fatalities were caused by"Other/exterior vehicle parts" or "Road surface." "Other/exterior vehicle parts" indicates the four-wheeled vehicle
body, excluding the tires. "Road surface" refers to the surface of the road and does not include road works
equipment such as guard rails and safety barriers along the side of the road. Over the three-year period, 568
people died as a result of "Other/exterior vehicle parts" and 566 as a result of the "Road surface."
600
500
400
300
200
100
0
Other/
exterior vehicle parts

Road surface

Tires

Road works
equipment

Other

Fig. 11: Distribution of injury-inﬂicting surfaces for cyclists suﬀering fatal head injuries (2009~2011)

Helmets are eﬀective at protecting the head when a cyclist collides
with hard surfaces such as exterior vehicle parts or the road surfaces.

 What is the situation regarding helmet use?

Fatality rate (%)

From the discussion so far, it is evident that helmets are very useful for reducing injuries. Let us now compare thefatality rates among cyclists wearing helmets and those not wearing helmets in actual accidents. In Fig. 12, thefatality rates based on the numbers of cyclists and passengers suffering head injuries over a five-year period from2007 to 2011 are plotted on a graph. It is evident that the fatality rate declines in the order of "Helmet not worn"
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3.5
3.0
2.5

㸨

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2.0

1/4

1.5

㸨

1.0
0.5
0
Helmet not worn

Helmet worn → Came oﬀ

Helmet worn → Did not come oﬀ

Fig.
g 12: Fatality
y rates byy helmet use situation (2009~2011)＊： The scope of the graph represents a 95% conﬁdence interval. The graph uses data from a ﬁve-year period (2007~2011)
because the volume of data for "Helmet worn → Came oﬀ" and "Helmet worn → Did not come oﬀ" is small and thedegree of variation considerable.

Wearing a helmet correctly reduces the fatality rate
to approximately 1/4 of the fatality rate for not wearing a helmet
EvE
en wheh n a helmet
h lm
hel ett isis worn, it cannott be
be expected
expectet d toto be
be effective
effffectiv
ti e if itit comes off
offf before
beffore thethe person suffers
suff
ffers theth impact.
impactt.
Even
when
Wearing helmets and fastening the chinstrap correctly are both critical.
ITARDA INFORMATION no.97

⮬㌿㌴஦ᨾࠉ⿕ᐖ㍍ῶ࡟࣓࣊ࣝࢵࢺ
≉㞟

Table 1: No. of casualties and estimated no. of fatalities byhelmet use situation among people suﬀering head injuries

Helmet not worn

Helmet worn
→Came off

Helmet worn
→Did not come off

No. of fatalities (people)

2,181

22

27

2,230

No. of casualties (people)

94,922

1,073

4,697

100,692

Fatality rate (%)

2.30

2.05

0.57

2,021

Estimated no. of
fatalities (people)

546

6

27

579

Total

（People）

The estimated number of fatalities in Table 1 (the bottommost row) gives the estimated figure based on the
DVVXPSWLRQWKDWWKHIDWDOLW\UDWHVDUHDOOWKHVDPHYDOXHVDV+HOPHWZRUQĺ'LGQRWFRPHRII  IRUWKH
numbers of casualties for each helmet use situation. It is estimated that if all cyclists wore helmets correctly, of all
WKRVHF\FOLVWVNLOOHGE\KHDGLQMXULHVRYHUWKHILYH\HDUSHULRG SHRSOH DSSUR[LPDWHO\SHRSOH  ZRXOGQRWKDYHEHHQNLOOHG:KLOHWKLVLVDURXJKFDOFXODWLRQWKHVHILJXUHVLQGLFDWHFOHDUO\WKDWKHOPHWXVHKDV
a significant effect.

Helmets are essential items

 for junior/senior high school students!

No. of cyclist casualties/
no. of pedestrian casualties

Finally, let us discuss what age groups need to put particular effort into wearing helmets. Fig. 13 compares thenumbers of cyclist casualties with those of pedestrian casualties for each age group. It is evident that for all age
groups apart from children under 6, the number of cyclist casualties is greater. In other words, once children start
using bicycles, the extent to which cyclist casualties exceed pedestrian casualties grows greater, peaking in the
junior/senior high school years in particular (9~14 times the number of pedestrian casualties).
16

Senior high school

14

Junior high school

12
10
8

Mature adults

Elementary school

6
4

1：1

University

Elderly

Young children

2
0
〜6

7〜12

13〜15

16〜18

19〜24

25〜54

55〜64

65〜74

75〜

Age groupAge group (years)

〜6

7〜12

13〜15

16〜18

19〜24

25〜54

55〜64

65〜74

75〜

Cyclists (people)

6,424

66,15564,82391,93474,041

239,770

85,03886,092

54,971

Pedestrians (people)

21,72536,566

7,182

6,700

18,565

105,11145,31350,32953,608（People）

Fig. 13: Comparison of cyclist casualties with pedestrian casualties by age group(2007~2011; aggregation of primary and secondary party casualties)
ITARDA INFORMATION no.97

ITARDA INFORMATION no.97

 Summary (findings)(1) Cyclist fatalities and injuries have decreased less than fatalities and injuries among other means of transport.
(2) A large number of fatal accidents are caused by injuries to the head and chest, while injuries to the arms/legs
are commoner among accidents causing serious/slight injuries.
(3) Injuries to the head, abdomen and chest have higher fatality rates.
(4) The commonest injury-inflicting surfaces are "External vehicle parts" and "Road surface." :HDULQJKHOPHWVUHGXFHVWKHIDWDOLW\UDWHWRRIWKHIDWDOLW\UDWHIRUQRWZHDULQJDKHOPHW%DVHGRQWKH
QXPEHUVRIFDVXDOWLHVDQGIDWDOLW\UDWHEHWZHHQDQGLWLVFDOFXODWHGWKDWLIKHOPHWVZHUHWREHZRUQFRUUHFWO\E\DOOF\FOLVWVOLYHVZRXOGKDYHEHHQVDYHG
(6) Among junior/senior high school students, the numbers involved in cyclist accidents are considerable, occurringat 9~14 times the rate of pedestrian accidents.

㸺 ཧ ⪃ 㸼  ㆙どᗇࡢ࣮࣒࣮࣍࣌ࢪ࠿ࡽࡢ㌿㍕「自転車用ヘルメット」の着用試行■ 自転車用ヘルメット着用の目的
ࠉ㆙ᐹᐁࡀ࣓࣊ࣝࢵࢺࢆ╔⏝ࡋࠊࠉᶍ⠊࡜࡞ࡿ⮬㌿㌴ࡢ஌ࡾ᪉ࢆ㒔Ẹࡢࡳ࡞ࡉࢇ࡟♧ࡍࡇ࡜࡛○ 道路交通法等法令の遵守と規範意識の向上○ 自転車利用者に対するヘルメット着用の促進○ 自転車による交通事故の防止ࠉ➼ࢆᅗࡿࡇ࡜ࢆ┠ⓗ࡟ᐇ᪋ࡋ࡚࠸ࡲࡍࠋ

■ 自転車用ヘルメット

ハードシェル

ソフトシェルࠉᖹᡂᖺ᭶᪥࠿ࡽࠊ୓ୡᶫ㆙ᐹ⨫࡛ᐇ᪋ࡋ࡚࠸ࡲࡍࠋ

出典 ： http://www.keishicho.metro.tokyo.jp/sikumi/kouban/bicycle̲heru.htm
ITARDA INFORMATION no.97

1) Junior/senior high school students, who cycle a great deal,
should consider helmets essential items andbe sure to wear them.
Okay!

You must
wear your helmet
when you ride
your bike.

2) Make wearing helmets a habit among
toddlers and children aged under 13;
efforts to make it mandatory toensure that children this age wear helmets
are currently being enforced.

ITARDA INFORMATION(1) Bicycles are vehicles too. Be sure to wear a helmet when you cycle.

஺㏻஦ᨾศᯒ࣏ࣞ勖ࢺ

 To reduce injuries when cycling3) Adults should wear helmets at thesame time, so that they are goodrole models for children.

(2) Cyclists who suffer heavy impact to the head, chest or abdomen should avoid brushing
this off and be examined promptly by a doctor.
(3) Cyclists should make use of elbow/knee protectors as well as helmets. Even cyclists who
find protectors too cumbersome when traveling should take care to protect themselveswith long sleeves, long pants and gloves, which can reduce the degree of injury in small
accidents.
㸦Author: Makoto Shiota㸧஺㏻஦ᨾ⥲ྜศᯒࢭࣥࢱ࣮は、平成４年（１９９２年）に国家公安委員会、運輸省
（当時）
、建設省
（当時）
から設立許可を受けて、公益法人として設立されました。
その後平成２４年（２０１２年）４月に公益財団法人に移行しました。
我が国で唯一道路交通法第６章の３の定めるࠕ஺㏻஦ᨾㄪᰝศᯒࢭࣥࢱ࣮ࠖࡢᣦᐃࢆᅜᐙබᏳጤဨ
఍࠿ࡽཷࡅࡓㄪᰝ◊✲ᶵ㛵であり、஺㏻஦ᨾࡢ㜵Ṇ࡜⿕ᐖࡢ㍍ῶࡢࡓࡵࡢ交通事故の調査分析を行っています。
当センターが行う交通事故調査は交通事故の低減を目的とした調査・研究のためのもので、警察の捜査や保険会社の調査とは全く別のものです。

බ┈㈈ᅋἲே஺㏻஦ᨾ⥲ྜศᯒࢭࣥࢱ࣮
࠾ၥྜࡏඛ‫ࢪ࣮࣒࣮࣌࣍ە‬KWWSZZZLWDUGDRUMSࠉ‫࣮࣓ࣝ(ە‬NRKR#LWDUGDRUMS
つくば 交通事故調査事務所

ITARDA INFORMATION no.97

11

公益財団法人 交通事故総合分析センター

4) Efforts should be made to raiseawareness in elderly cyclists;
for example, that wearing
helmets can compensate for
their reduced physical resistance.