DoH Digital Library: Trevor Taylor Awards

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Department of Health Library Services ePublications - Historical Collection

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To apply preservation treatments, including digitisation, to a high value and vulnerable Historical collection of items held in the Darwin and Alice Springs libraries so that the items may be accessed without causing further damage to the original items and provide accessibility for stakeholders.

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Please note: this document is part of the Historical Collection and the information contained within may be out of date.

This copy is a reproduction of an original record. Please note that the quality of the original record may be poor and cannot be enhanced with the scanning process.

Northern Territory Department of Health Library Services Historical Collection

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ABSTRACT

Boxing nas come under strong attack trom a large number ot

medical 2ssoc1at1ons over the past two decades and many doctors have actively sought a ban on boxing and campaigned for i t s elimination from the u1ymp1cs ano a11

have often based this opposition on the belief that unequiocal

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In ^i:··I c~ r"1 :-·, \,,,! .. .--. .. t i 1r-+· \,, i t is argued that t.hE:• ^CJ·t·

associated with this activity can not be determined until there is valid quantitative information on the nature of the head trauma that boxers are commonly exposed to. This has hitherto been unavailable.

Equipment that enables such information to be obtained has been calibrated and testedu ~3DE:•C:L

+

^:i.^C::,':~.lJ. '/ i t

: : I

t: C) rl :;::. t:. I'-L!. c: t:. E? (J i:

collects real- time information about the forces acting on a boxer 's head and relays tn1s via a radio link to recording

equipment. The successful preliminary testing of this equipment is described in thi~ report.

1ne potential now exists to: immediately sluµ fiqhts

1+

^punches

greater than a predete~mined va1ue are oe11vereo, ^"I ^! ^'1 ^I

accurate record of head trauma each boxer has received, make meaningful comparisons with other sports in which head

injuries are common, and establish at last the details of the risk v. exposure curve for those who persue this activity.

Society may well decide that boxing is no longer an acceptable activity: this report provides the basis for obtaining the rational medical evidence needed to make such a decision.

DL HIST 617.1027 NIT 1991

I Y'

DL ,._ S G\1.,02,

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HEAD INJURIES, ENCEPHALOPATHY and BOXING Resolving the Controversy.

Philip Nitschke

(4)

.I

Acknowledgements

Tristan Pawsey for her general support and help with the s t i l l p h c:i t. u q !' .. Et p h y .. D c:i u C.J l¹J h ('"::! (~ n ·f o I'.. h i ~=· h E· l p hi i t h t h (-? c i n e rn (-? t o (;J r 01 p h y ..

MEB for advice with the electronic design and access to data.

Hamish Holland and the anaesthetic deoartment at RDH for maK1ng tne time available to complete the work.

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particular, the efforts of the two volunteer ~~vprs who put up with such a loT while the series of bouts was being recorded.

(5)

1.

Introduct ion.

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first recorded as an Olympic event in 688 BC. Modern boxing

evolved in Br i tain in the 17th century and spread with the empi re across the olobe. Gloves were made compulsory 1n the 1880's when

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when the fatality rate had been shown to compare f avourably wi th

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~=-~J C) r·- ·[. "

Martland provided the first medical description ot the

confusion, leg dragging, tremor. slowing of muscular movements~

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1n1s ent1tv 1s now s encephalopathy ,

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The debate over whether or no~ amateur boxinu causes chron1c brain damage has raged in the medical literature over the past two decades" The World Medical Association recommended a total ban on the spor t in 1983 (13). and in 1989 the American Medical Association and t he US Surgeon

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statements opposing boxing since 1973. In 1990 the AMA proposed t·. I-·1 .::·:·{ ·i.:-. l:J c:; ;< :!. r-, t;J i:J t7: = ' cj v .. c:)

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sporting contests ^{( 15}⁾^"^l^!

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research done and questioned the attention the soort has

attracted f r om the medical profession (16) . Recently, 1n the most comprehensive retrospective surevey yet done, Swedish r esearchers

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p E!. I'-t :i. c:: i p ::,-.. t :i. n q :i. n t: h E? '==· p Dr· t. ¹^' ⁽9 : 1 , 2 , 3 & 4 ) .,

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L.

The Current Debate.

The~~ has been a problem with all previous attempts to resolve

the question about the r elative risks and lono term neurological

consequences of boxing. One approach has been to find a group of boxers who are willing to be examined in detail, eliminate those

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and then subject those left to rigorous testing. Extensi ve

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In general the results of the extensive American surveys conclude

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^b^(·::i^t.tt s ^{! !} ⁽8 ) . -:3. r·, cJ ·; m D 1,.. '.:.7: ,,-E· c en t 1 ·y- t h at ^'!u n E· q u. i o c a 1 e v i d enc e of organic cerebral dysfunction exists in more than 80% of boxers ':::. t U cJ i E? d ^!^! ⁽4 ) "

··r i .. ·1 t:~ rn c:i ::::. ·i.~. (j F:~¹t:. .:'::!. :i. J. i::~ c! ,::·( r-: c.i t:::¹;< t·. E' 1-: ~=-i \/ ^t::., t-e:? ·i.~. r-c:J s r-) c-? c ·t ^{1 \/}^E· st 1 __ t d ~-/ ':' et. c: a r·· 1r9 i ^E~d out was published in Sweden in a series of +our papers earlier

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of soccer players, atheletes and conscripts were similarly

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discernab:i.e difference between the four groups and that !!(Swedish

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In reviewing these published results, a numoer of points need to be kept in mind. Generally, the American studies included both professional and amateur boxers~ whilst the Swedish study

involved on:i.y amateurs (Sweden banned professional boxing 1n

l ~ b b J . Also, amateur boxing in Sweden is more closely controlled,

with specific legislation governing many aspects of the sport.

(11) . Thi5 may explain some of the discrepancy. Of greater

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hnv. Most would agree, blows to the head can cause long term brain damage - the question is. are amateur boxer s at risk, and 1t so~ should this sport be banned?

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The Experiment.

There has been +ew attemots t o actually quantify the damage done to a boxer during a bout. The retrosoective studies had to rely on the crudest of data. Did the referee stop the fight, d1d the boxer loose consciousness, how many rounds were actually fought?

Brayne et al (10) suggested that creatine kinase isoenzyme BB levels could be used to quantify possible brain damage in boxers by est ablishing the degree of disruption of the blood brain

barrier; some correlation with the number of blows to the head was demonstrated.

in a.

series of animal experiments conducted 1n 1975. He showed that

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Laboratory measurements of the force that can be developed by a

trained boxer have been made by Atha et al (12). Thev constructed a ballistic pendulum and were able to demonstrate that Br i t i sh

q ^l^··./E' .i. t:. an acceleration of 520 m/s i s

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real time measurement of the number and intensitv of the blows

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Experiment design

In this experiment an inertial sensing devise ha~ oeen

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acting on a person 's head to be detected and measured. The recorded signal is processed, amplified and used to modulate a t. r--=~! r-1 ^5:.fr: :i. ·t. t ^F^E.'r.. ~~ Ci t:. !···: .:·::t t·. t: f": c:::: i r-, ·f ^C)r-in ^C^:'t.·f.~. i c:, r·i c: ^-^:^::f.r1 t:i e ^1·-e c~ e i \/ t?. cl 'J ,·=t r1 i::=t 1 ... -/. s e ci C) 1,··

stored at some point remote from the sensor. Miniaturisation of the sensor has been accomolished so that the whole devise <Photo

1) weighs only 105gm and can r eadily be attatched to a boxer's protective headgear. Calibration of t he devise has been carried out 1n tne laboratory and testing of t he equipment m2\c.iE: dur-ing an actual fight. It is now possible to quantify the number of tne punches that connect with a boxers head and tne intensitv of the

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gives instant information on the energy conveyed in each punch.

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Photo 1. Inertial

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...,- - ' ' I ^{v '}

4.

The Sensor

Both rotational (angul ar ) and linear acceleration of the movable head lead to brain damage (13) . Linear acceler ation can occur in any direction 1n the two dimensi onal plane oerpendicular to t he cervical spine. Rotational acceleration occurs arond the spinal c o t'"· d ( Fi g 1 ) .. I t:.

+

^D1 l o ^~^·Js t h <='. t. t h e ~:} :~ n ~==· o !'.. mu ~st b e ab l e t o de t (~ c t these components of acceler ation in this p1ane. The design adopted is shown in F i g - · ^H mass (0.4g) is attatched to a

conductor and suspended 1n an ~~1a1 magnetic field. Acceleration in any direction in the plane perpendicular to the field results

1n the induction of a current through the conducter. Oscillations

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output of approximately 20mW from a 20cm tuned areal . Modulation

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this frequencv by the sensor enao1es ^I ^'I tne 1nstentan1ous ^{I :} ^' ^: ^I ^'

accelerations ot the head to be r ecoroeo up to 50 meters from tne ci E:.,t:. ec~ -!::. C:)i,.. " ( See Fig 3) ^II

The ^~_L1etec1:or

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The sJgnai 1 s received and decoded by~ commercial receiver.

Audio output oroportional to acceleration is rectified and

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up ^1Jccn to test ~ne system.

Calibration.

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sensor by the application of Kncwn forces. The detector was suspended ana a spring stretched to prov1oe tne requ1ren ^I ^' ^I ^{l :} ^' ^' ·+· C)fr-C (~ ^K

Sudden release of the detector resulted in an pulse that could be

' ' '

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The trace shown on

recorded. The final calibration graph 1s shown in Fig 4 ano

: . ,•• 'I : .

reao1ng o~ acce1erat1on ^{( CJ!·-} ^{: fJ} ^..^=-~-⁾ C:)·f"

a boxer's head during a ~1qnt.

(10)

Fig. 1.

A

Rotational Acceleration

B Linear Acceleration

Linear and Rotational Acceleration from Boxing (from Lampert 1984)

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Calibration graph for Inertial Sensor Pulse Height (mV) V Acceleration (g's)

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(14)

Table J_

Numbers of Head Blows by Round

Round l Round 2 Round 3 Round 4

Accelerometer 21 12 32 34

Observer l 18 10 27 29

Observer 2 15 9 33 25

(15)

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:In Vivo' Testing.

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( =

¹ ^C)^·f t f·1 (::!

development of this system and offered to provide faci l i t ies for i ·t. ~:~. ^·^t.^{E~ ~::;}^t:.^:^i.r-: ^t;_^:J^.. CJ r1 J --:,/ c) r-i e ci F:? t E· c: t·. c:., ;·· t.AJ ct s ,·:·:·t \ / ,::t i 1 ^,:.-1.i:i l e a r-: cj ·t r·1 i s ~ ... ,., E:t s

~~-t·. ·t. ::~. t:. c:: r·: E~ c! t·. c:i -!::. i·-: {::':¹ 1:J r· C) t~ r:::, c: ·t. :i \/ E:, !···: E~ ,·:·:°!. c:1 ~.:.: (:::' E:·t ,.... c:, ·f -:?.. \/ t:, 1 tJ 1-: t·. c? e 1- a. rn at E~ Lt r·

the occiput and placed

• I • I

was pos1~1oneo over against the ~kull.

r:· c:J t..!. (' ^·1 rn 1 i· .. : c.1. t:. ,::-:, r-· c:; 1...1. r .. , cl

~=-

^~\!f.7! i .... (·:-::: r-.. (·:·?} c: c:i r·· cJ F.-:, o ^II lJ Lt t·. ~J t.t t:. ·f· r· CJ rn t: !-; t7:.' ~s er .. : ~~ C) ,,- 1/·J \·:t s

disolaveci on the oscilloscope and recorded on audio and video

~ape. ~t111 photographs of the boxers were taken throughout the

~1gn~ to complement the video record.

2xchanoe between the boxers" The sensor is visble on the head of t ! .. 1 (:::, !::> C) ;< E:, i'.. C) i-1 ·[:. j··1 (?. r-i ~J f-·: t. " ·r· ^t··¹^f:¹ ^J^:)f·: ^C)*-~ ^fJ ^S(·1 C) i⁴J S C:) f"i (? 0 ·f t: ~-··J CJ S i-1 C) r-t. J. e ·f i:

jabs striking the riqht boxers jaw~ and the trace of these blows

:~~ r·1 ,·:·:·t 1 \/ :::; :i. :::; c.~, -~:: t. i· .. 1 i:-::.-:1 i'""' (-:::..i ~==· Lt. .L -r:. ~::. ¹.,\J ,-.. ~ -:::~ r:: E:·~ t· ... t ... i ^(;:!c:~ c:i 1 .. t t· .:::,. ·f t·. i::-:~ j·- t·. i ... : e ·f i g r-: *:. ^V·J^r-1^er^{.. :} ^-r.:.r·: c-:7:

video and slide ~ecords were compared with 2 chart recorder print out of the information from the accelerometer.

Hesults.

On reviewing the video t3pe ano watchino the simultaneous display o+ the accelerometer record from the video sound t rack . i t wa~

~nat there was good

! : 'J I

tne 2cce1erome~er trace and the witnessed blows to the

Table 1 gives the numoers oi punches in each round as assessed by t: V·J {:} C:) t) ~:; i-:7.' f···· ·· .. ,, ~:.::, , .. -~~ 'J E:°!. r··! c! '!.':. ~-·: E: r··: ^{J. ..}i. en[:> E:• fr· CJ ·f ^{! !}^Si ':J r: ]. +: :i. C: i:1 r) 1.°.: ! 1 b i c:; ^{V·J :::;} CJ E~ t. E¹r· ^fT:i ^flE CJ

cJ ·y.- i·:. !· .. i i:-::-:, ~::i r-~¹·t. E~ c:: t·. cJ r·.. .. ⁱ¹r::; i i:J r1 i ·f i c: E:!. r--1 t: ^{! i} :i. r·1 t i· .. 1 :i. ~:::. c:: c) 1-: t:. i:-:7: ::-~ t: ^,i,j,·::ts:. t: .:·:i. i< t-:2 r .. 1 ^·=·=1.s

recorded pulses with a magnitude gre3ter than 2X the background.

In practice this was easil v established f rom the trace. :nere

•• I ' " "1 I • ,"'

~u1ses correspono1ng to acce1era~1ons o~

iUU m/s/s (10. 2 g 's >

It was not~~-· to establish from the video to power of the

rj

^{t..t r-1}c: r·1 :, ·1-f .. : E:' ;-··· E:· v-.J ,3. ·:::. i:: c) ri ·::::. 1 cJ e r·-.:::t !:) J. e \/ ~\ 1-·-i i-:t t·. i C) r: b (~ t ~""J (~ E:¹1-, ~:, E-:¹r· c:: t:=t i \/ i i~7= cJ ·f CJ:;-c t.~

Discussion

The preliminary t esti ng cf the equipment snows that the system functi ons anci that useful information can be derived from i t . 1n particular, the number of significant head blows during a boxing round is immediately available" The fact that observers generally underestimate the number of-punches is readily explained by the

~act that the view is commonly obscured