LAXITY AND THE TIBIAL NEUTRAL POSITION IN CRUCIATE DEFICIENT KNEES by Wagner Calio Batista A Thesis Subrnitted to the Faculty of Graduate Studies and Researçh in Partial of the Requirements for the Degree of Master of Arts (Education) Departrnent of Physical Education Division of Graduate Studies and Research Faculty of Education McGill university Montreal, Quebec. (c) Wagner Calio Batista, March 1992
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LAXITY AND THE TIBIAL NEUTRAL POSITION IN CRUCIATE DEFICIENT KNEES
by
Wagner Calio Batista
A Thesis Subrnitted to the Faculty of Graduate Studies and Researçh in Partial ~llfillrnent of the Requirements for
the Degree of Master of Arts (Education)
Departrnent of Physical Education
Division of Graduate Studies and Research Faculty of Education
McGill university Montreal, Quebec.
(c) Wagner Calio Batista, March 1992
ABSTRACT
The present st.udy attempted to characte.cize laxity in
cruciate deficient knees using the Genucom System compariI~
the neutral to the resting position of the tibia. A
quadriceps active technique was compared to a passive protocol
at four knee flexi.on angles: 60, 70, 80 and 90 degrees. Eight
ACL and eight PCL injured subjects perforrned active and
passive anterior-posterior knee drawer tests. These tests
were perforrned during two sessions to verify their
reliability. Posterior and anterior laxity werc recorded for
the peL and the ACL injured subjects, respectively. Ldxity
was measured at forces of 60, 90 and 130 Newtons. A feedback
unit (Biostim 6010) was used to monitor Inuscular contraction
during application of protocols. Results revealed a
significant anterior tibial shift (p<.05) in the PCL injured
patients when cornparing active to passive tests. No
significant anterior tibial shlft occurred in the ACL injured
patients when performing the same comparison. The Genucom
produced rel iable resul ts across two sessions for both PCL and
ACL groups. Posterior laxity of PCL injured subjects was
similar for knee flexion angles between 60 and 90 degrees.
ACL injured subjects had statistically sirnilar anterior laxity
dt knee flexion angles between 60 and 90 degrees.
i
ABSTRAIT
L'étude presente a tenté de caracterizer le déplacement
du tibia des genoux avec les blessures des ligaments croissés
par l'usage du Systeme Genucom pour comparélnt III posltion
neutre i la position de repos du tibia. Une technique nctif
des muscles quadriceps était compar~ ~ un protocole passif en
flexion du genoux par quatre angles: 60, 70, 80 et 90 degrés.
Huit sujets, -rec les blessures du ligament croissé postérieur
(Lep) et huit sujets avec les blessures du Ijq~ment croiss6
antérieur (LeA) accomplirent des tests antéricur-postérieur
actif et passif du genoux. Ces tests ont été rél i t durdnt doux
sessions pour verifier leur ,... ,.
surete. Les doplaccmonts
postérieur et antérip"~ sont enreg Istré respect bernent pour
les sujets avec les blessures du LCP et du LCA. Les
déplacements sont ~
mesure en contrainte de GO, 90 ct ]]0
Newtons. Une unité de feedback (Biostim 6010) Gtllit util isé
pour contr81er de contraction musculaire durant l'nppl1catlon
des protocoles. Les résultats révélèrent une dév iat ion
antérieur significative du tibia (p<. 05) dans les patj ents
.. . avec les blessures du LCP apres comparaIson entre les tests
actifs et passifs. Aucune déviation antérieur ùu tibia
n'apparaissait dans les sujets avec les b]e~jSllrO;; du LCA
lorsque la même comparaison a été accomp 1 i r. J J(' Genucom
produisait des résultats sûr aux travers deux seSSlons pour
les patients avec les blessures du LCP et du LCA. Le
ii
déplacement postérieur du sujets avec les blessures du LCP
était similaire pour le genoux plié aux angles entre 60 et 90
degrés. T,'" ~ suj ets avec les blessures du LCA avait
déplacement antérieur statistiquement similaire aux genoux
plié entre 60 et 90 degrés.
iii
• ACKNOWLEDGEMENTS
This thesis was made possible w i th the dSS i st'::l I1L'e o!
individuals and organizations. 1 dm deeply thi1nktu1 to:
My parents, Wi Ison and Margaridd who supportcd ml' doc i~, Ion
to pursue graduate school and bolsteréd my reso l vc to comp 1 ct 0
the task with love, encouragement and undcrstanJing.
Dr. victor Matsudo from the CELAFISCS orqùn i Zélt i on \Vho
ignited and fed the "s cientific flame" in my pcn~un.llitl',
CNPq, a researchcouncil in Brélzil that providod filli1nt-i.l1
help to this project.
Dr. Thomas Blaine Hoshizaki who gavE' the initictl input fo/-
this thesis and allowed the use of the Laborcltory 01
Biomec..hanics in the Department of Phys iCd l Educa t i orl dt Mc 'C i 1 1
University for data collection.
Mr. Tony Fiorentino, t'rom Medlcu~; "Jho rrovid .. d tlll'
feedback unit Biostim GOlO and referred subjccts ta tlle I,!I).
Dr. Eric Lenczner for his clinical input (lnd con!:.;t,lnt
referral of subjects to the labo
The subjects of this study for their cooperation.
Dr. Dan Marisi, ". .. Dr. Helene Perraul t, Mrs. Sonya l1d t tho',;:;,
Mr. Vassilis Vardaxis, Mrs. Lorri:dnc Coi fin, flJr. ~~t_éph,lIi('
Perrault, Mlle. Danny V~zina (lnd professors and staff in th0
Department of Physical Education whosc comments
contribution to a stimulating atmosphere helped in thp
developrnent of this project.
iv
1 Dr. Greg Reid,
Education who acted
chairman in the Department of Physical
as co-s'lpervisor of this thes is and
provided valuable input.
Ron Turchyniak and Torn Gilmour for their constant
ass istance and commi tment to friendship that enabled me to
survive through difficult tirnes.
Finally, l wish ta extend the greatest appreciation ta Dr.
David L. Montgomery and his wife, Carol Montgomery who
somctimcs acted as a family to me. His patience, enthusiastic
gujdance and encouragement provided me with the attit'.des
injuries and 10 had unilateral chronic posterior cruciate
tears. The opposite knee had no abnormalities.
To establish ACL and PCL deficiencies, aIl subjects were
tested on the Genucom system with a force application of 90
Newtons. For ACL patients, the parameter of inclusion was
anterior tibial displacement equal or greater than 3 mm for
the involved leg compared to the intact leg when assessed at
60 degrees of flexion. For PCL patients, the parameter of
inclusion was posterior tibial displacement equal or greater
than 2.5 mm for t~e involved leg compared to the intact leg
when assessed at 90 degrees of flexiun. This operational
definition excluded two ACL and two PCL injured individuals
from the experiment. The sample size was thus reduced to 0
subjects.
The 16 subjects in this investigation ranged in age from
16 to 37 years. There were five males and three females in
the PCL group and three males and five females in the ACL
group.
3.3 ~esting Instruments and Protocols
3.3.1 The Genucom System
The Genucom Knee Analysis System (FAR orthopaedics, Inc.)
is a device that includes a reclining chair mounted on a six
36
degree of freedom electrogoniometer linkage. This goniometer
is attached ta the distal third of the tibia, where it records
the knee position (joint angle) and displacement (tibial
laxity) based on previously digitized coordinates.
within the seat there is also a six compone nt forco
dynamometer to measure external forces and moments placed on
the knee joint. The system is linked ta a computer for dat~
acquisition and processing.
The Genucom is controlled by software placed into one al
the two disk drives located in the inferior portion of the
chair. The Genucom program formats diskettes, where each
subject's data is stored.
The Genucom examination started with the subject seating
on the chair. The trunk was restrained with a velcro boIt at
the waist. Three thigh pads compressed and restralneù the
distal third of the femur in the medial, lateral and posterior
directions. First, the lateral pad was tightened. Forces
equal to 90 and 130 Newtons were then applied to the superior
and medial pad respecti vely, and tightened. 'J'wo latera 1 pact:;
were also applied on the greater trochanter arOd. l Il th j~;
manner the trunk, hip and fernur were stabil ized.
Seven anatomical landmarks of the lower extremity were
digitized to establish a coordinate system on the knee, ta
which aIl movements were referenced. The digitizcd landmarks
included: (1) tibial crest 13-16 cm below the tibial tubcrclc,
(2) tibial crest 5-7 cm below the tibial tubcrc]c, (1) tibidl
37
tll~·.rcle, (4) medial edge of the tibial plateau, (5) medial
femoral condyle at half-width, (6) lateral femoral condyle at
half-width and (7) lateral edge of tibial plateau.
The innovation of the Genucom examination includes a soft
tissue compensation procedure performed for both active and
passive types of tests. This procedure accounted for the
amount of soft tissue compress ibil i ty so that only true tibial
and femoral motions could be measured separately. Through a
compensation, soft tissue deformation was accounted for in
medial, lateral, superior, inferior, anterior and posterior
directions (relative to the femur). This was achieved by
applying manual forces in different directions. Each
procedure was always performed two times according to the
following:
(1) A force of 130 Newtons force was applied with the palm of
the hand to the medial and then to the lateral femoral
condyle.
(2) A force of 130 Newtons was appIied ta the top of the
fernoraI condyles downwards.
flexion.
The knee was at 90 degrees of
(3) A force of 130 Newtons was applied onto the heel of the
foot in the superior direction moving the distal end of the
fernur anteriorly. 'l'his was performed wi th the knee at 90
degrees.
(4) A force of 130 Newtons was applied to the patella in the
direction of the fernoral axis.
1 38
Each force was applied repeatedly due to the fa ct that the
Genucom software correlated the two soft tissue meilsurcs.
High correlations (90 % or more) betwcen two trials \vere
accepted. Soft tissue compensat ion [or ùcti ve tests WclS
similar, except for the fact that, during force application,
subjects were asked to flex their legs at a 60 degree angle.
This angle was chosen with the assumption that it wou1d be the
angle used in the protocol when quadriceps activity would be
the highest. Therefore, more soft tissue mOVCJl1ent woul d
occur. To maintain the knee at this flexion anrjle (i0
degrees), a goniometer was attached to the patient' s log. 'J'he
reference l ines of the goniometer were aU gned wi th the
patients greater trochanter and latera1 ma11eo]us.
Once the compensation was completed, the e lectrogon iometel
was attached to the distal end of the leg. 'l'he eXi1m i no 1-
started performing the anterior-posterior examination. Be>loro
test application, the Genucom sampling frequency was set at JO
Hertz.
Before the protocol was initiated, subjects were a1lowed
a 10 minute practice session, with special emphasis on the
application of active tests. They vJGre instructccl hOvl ilnd
when to keep their legs at a flexion an~lc by contrélct i n(.)
mainly their quadriceps muscles. This was done with the help
of the biofeedback unit and the evaluator's instructions.
The Genucom protocol started with three trials at GO, 70,
80 and 90 degrees of knee flexion on the intact s ide vii th the
1 39
subject relaxed (passive tests). The intact side was tested
first in order to develop the subject' s confidence in the
protocol and to prevent muscular defence. At each angle and
trial, three anterior-posterior drawer tests were recorded.
Subjects relaxed with the help of the feedback unit and
evaluator's instructions and judgement.
Following the passive tests, subjects were administered
the active tests with contraction of the quadriceps muscles.
Subjects were tested on the same leg at flexion angles of 60,
70, 80 and 90 degrees. The Genucom system allowed constant
monitoring of the joint angle as its electrogoniometer was
attached to the subject's leg at aIl times. The instrument
indicated a numerical output containing the flexion angle,
force, rotation and moment of the leg. During application of
active tests, the leg was placed at a specifie flexion angle.
The subject was asked to keep that position while the
eva1uator verified that the hamstrings were re1axed by
listening to the auditive output, by observing visual readings
of the feedback unit, and by palpating the posterior aspect of
the subject's thigh. The left switch of the Genucom pedal
control 1er was then pressed. Testing parameters on the
Genucom monitor (force, displacement, rotation, and moment)
were set to zero. Upon activation of the Genucow, by pressing
the right switch on the pedal controller, anterior-posterior
forces were applied.
The involved side was assessed using the same sequence.
40
At each test (anterior or posterior), a manual force \vé1S
orthogonally applied to the proximal tibia. Tibial laxity was
determined at 60, 90, and 130 Newtons for both active and
passive tests.
steiner and co-workers (1990) using the Genucom dcterm ineù
that test variability as a percentage of the measurcmcnt was
greater for stiffness and compliance compared to measuremcnts
of anterior and posterior displacement. They sugqestcd that
the hiqher stability found for laxity scores recommcnd its use
as a dependent variable ta aS5ess knee -joint i ntcqrl ty. 'l'hey
also found that diagnostic sensitivity and corrcctncss won'
less for stiffness and compliance than for those of simple
anterior displacement.
3.3.2 The Biostim 6010
The Biostim 6010 (Mazet Electronique, Inc.), is a [eedb~ck
uni t that gives a numerical analog output of the muscull\r
activity translated into millivolts. The device provjdcs an
auditive sign which varies according to the intcnsi ty of
muscular contraction. Numerical and auditive outputs vICr0
calibrated to their most sensitive mode before ca ch tcstinq
session according to the manufacturer' s rccommenda t l ons (Ma ",cot
Electronique, Biostim 6010 user's manual).
After skin preparation, surface electrodes were attachcd
as close as possible to the motor point of the subject'~)
hamstring muscles according to the manufacturer's
l 41
recornmendations. The ground electrode was placed at the head
of the first metatarsal of the limb to be evaluated so that
the electrode would not interfere with the application of the
test protocol. To minimize rnovement of the electrodes, they
were fixed ta the subject's thigh with tape. The skin surface
was cleaned with alcohol to minimize electrical interferences.
A gel was used to improve electrical conductance.
The Biostim was set to i ts most sensi t ive mode. Each
electrode channel was regulated at 5 millivolts, representing
a true sensitivity of 1.6 millivolts according to the
manufacturer's manual.
After the sensitivity was set, the machi~e's auditive and
visual output were regulated. SUbjects were asked to perform
a maximum contraction of the hamstrings (knee flexion against
a resistance). The potentiometers that regulate auditive
output were calibrated to the 100 percent level during the
maximum contraction.
During test application, sorne movement of the electrodes
was observed. This produced sorne output that co'lld be
confounded with muscular activity. To solve the problem, two
criteria were employed to disregard tests. First, tests were
stored if there was no auditive output. Second, if there was
a sou~d, numerical outputs equal or greater than 5 millivolts
were used as a criteria for exclusion of tests.
It is important to note that no true measurernents of
1 electromiography were employed. The use of the Biostim 6010
· l was an atternpt ta: (1) select tests withaut undesirùblc
external muscular guarding and (2) help subjects to cantrQct
mainly their quadriceps when the active protocol Wé1S employcLl.
3.4 Treatment of Data
Each patient had three anterior and threc posterior tesL;
per leg (invalved and intact), per type of test (~ctivc Hnd
passive), and per session (1 and 2). Each test WQS performcd
at four angles of flexion (60, 70, 80, and 90 degreos). Uninq
the raw data, a pragram was designed to read the laxity scores
at ~orces of approximate1y 60, 90, and ]30 Newtons.
Three trials were performed for cach type of test, sossion
and angle of flexion. A mean of the three trials w~s
calculated. A computer program calculated the differenco in
tibial displacement for the involved 1eg compared ta the
intact leg for each subject.
3,5 Statistical Analysis
Means and standard deviations were calculQted for iHJ",
weight and height of the peL and ACL subjects. stat h,t i ca J
analyses were performed using SPSSX (statistjcal Package for
Social Sciences - version X) on the McGi11 university System
Interactive Computing (MUSIC).
A three-factor ANOVA was performed for dnterj or <.lOd
posterjor 1axity scores. The factors were: (1) type of test
(active and passive), (2) session (1 and 2), and angle of kncc
l 43
flexion (60, 70,80 and 90 degrees). A .05 probability level
was chosen for statistical comparisons. 'l'he exper imental
design is presented in Table 1.
Table 1: Experimental Design.
Test
Ses. Sess ion 1
Flex. 60 70 80 90
Subjects
1 2 3
8
Active
Session 2
60 70 80 90
Passive
Session 1 Session 2
60 70 80 90 60 70 80 90
Dependent variable: tibial laxity for involved - intact leg
To test the six hypotheses outlined in chapter l, this
experimental design was repeated for six analysis. These
analyses were:
1. PLAX for PCL patients at 60 Newtons.
2 . PLAX for PCL patients at 90 Newtons.
3. PLAX for PCL patients at 130 Newtons.
4 • ALAX for ACL patients at 60 Newtons.
5. ALAX for ACL patients at 90 Newtons.
6. ALAX for ACL patients at 13 0 Newtons.
4.1 Introduction
CHAPTER IV
Resui ts
44
The obj ectives of th is study were to test crucj ote>
deficient knees under two test starting positions of the
tibia: resting and neutral. Using the Genucom System,
anterior-posterior knee drawer tests (active and passive» wer0
administered to 8 PCL and 8 ACL injured individuals. 'J'Ile
subjects were tested during two sessions with the knec <lt fou/
angles of fI ex.:... on (60, 70, 80, and 90 degrees). 'l'he dependcnt
variables were posterior tibial laxity (mm) for the PCIJ
subjects and anterior tibidl laxity (mm) for the ACL subjccts.
For the PCL inj ured subj ects, i t was hypothes i :~(~d thilt
posterior knee laxity at GO, 90 and 130 Newtons wou] d be
similar during active and passive tests, dur ing sess ions 1 and
2, and for the four knee flexion angles. For the ACL inj ure 1
subjects, it was hypothesized that anterior knee Jaxity at (J!),
90 and 130 Newtons would be similar during active and pc1SS i Vt>
tests, during sessions 1 and 2, and for the four knec flexion
angles.
4.2 Characteristics of the Subject~
This study included 8 PCL and 8 ACL injured subjccts who
were referred by orthopaedic surgeons. Physical
characteristics of the PCL and the ACL subjects arc incJudcd
45
in Tables 2 and 3, respectively.
Table 2: Physical Characteristics of the PCL Subjects.
Subject
1 2 3 4 5 6 7 8
Mean S. D.
Gender
F F F M M M M M
Age (yrs)
30 28 27 37 26 23 25 36
29.0 5.1
Height (cm)
167.2 177.8 154.9 172.7 177.4 198.1 185.4 182.9
177.0 12.8
Weight (kg)
58.8 67.9 45.3 77.0 65.7 97.5 74.9 90.1
72.1 16.7
Table 3: Physical Characteristics of the ACL Subjects.
Subject
1 2 3 4 5 6 7 8
Meiln S. D.
Gender
M M M F F F F F
Age (yrs)
29 21 16 21 23 26 28 24
23.5 4.2
Height (cm)
177.8 185.4 170.2 154.9 167.6 170.2 154.9 165.1
168.3 10.4
Weight (kg)
77.6 86.2 68.0 49.1 59.0 61. 2 52.2 58.1
63.9 12.7
Medical information was collected on each patient. This
information is shown in Table 4 for the peL subjects and in
'l'able 5 for the ACL subjects. The criteria outlined by Daniel
et al. (1985) and Anderson and Lipscomb (1989) were used for
selection of subjects. AlI PCL patients performed passive
posterior tests at 90 degrees of flexion at a force of 90
Newtons on the Genucom. Ta be included in this study, the
subjects had ta present a posterior knee laxity of at least
·1 G
2.5 mm averaged across six trials. AU ACL patients perfonned
passive ante ri or tests at 60 degrees of flexion at il force of
90 Newtons on the Genucom. To be included in this study, the>
sUbjects had to present an anterior knee laxity of at lcast
3.0 mm averaged across six trials.
Table 4: Medical Information for the peL Subjccts.
SUbject Date of Date of oiagnosis PLAX Injury Arthroscopy (mm)
------------------------------------------------------------1 Feb 1991 Jul.,1991 peL, MM 7 • J ~ 2 Jan 1991 May ,1991 peL 2.60 3 Apr 1989 Aug.,1989 peL, MeL, LM 7 .80 4 Jan 1991 Sep.,1991 peL 2.60 5 Jan 1991 Jun.,1991 peL 2.90 6 Jun 1989 Dec.,1989 peL, MM 3 • Il 0 7 Mar 1989 Aug.,1989 PCL, MCL 2. 70 8 Sep 1990 Feb.,1991 PCL, LCL 2 • (,0
Table 9: ANOVA Results at 90 Newtons for the peL Subjects. ------------------------------------------------------------Source df SS MS F p ------------------------------------------------------------Test (T) 1 18.60 18.60 4.58 .03(*)
Session (S) 1 4.20 4.20 1.03 .31
Knee Flexion (F) 3 4.51 1.50 0.37 .77
T x S 1 0.12 0.12 0.03 .86
T x F 3 20.99 6.99 1.72 .17
S x F 3 1. 61 0.54 0.13 .94
T x S x F 3 0.40 0.13 0.03 .99
Error 112 455.17 4.06 ------------------------------------------------------------(*) p < .05
Table 10: Mean PLAX at 130 Newtons for the peL Subjccts.
Test Flexion Session Mel1n s. [).
Active 60 1 4.72 :: •• ~ 0 2 4.95 :'.32
70 1 4.05 2.23 2 4.44 2.2G
80 1 3.27 1.BG 2 3.64 0.99
90 1 3.90 ;~ • 31 2 4.00 ) .)C)
Passive 60 1 2.00 l. ~d 2 2.67 1.60
70 1 2.22 /. 1 r)
2 3.55 ) ~- 1 ..... :.J J
80 1 2.94 1 • ~30 2 3.47 :J. (,l
90 1 3.72 3 • () n 2 4.29 L ·1tl
Collapsed cells Mean ~; . /).
Test Active 4.12 2.0tl
Passive 3. Il
Flexion 60 3.59 /.4'j
70 3.57 ;~ . ~ 'J
80 3.33 l.,n
90 3.98 /.. (J'J
Session 1 3.35 2.24
2 3.88 2.42
1 55
Table 11: ANOVA Results at 130 Newtons for the peL Subjects. ------------------------------------------------------------Source df SS MS F P ------------------------------------------------------------'l'est ('l' ) 1 32.00 32. 00 5.88 .02 ( *)
Session (S) 1 9.14 9.14 1.68 .20
Knee Flexion ( F) 3 6.96 2.32 0.43 .74
'}' x S 1 1.85 1. 85 0.34 .56
'l' x F 3 31. 26 10.42 1.91 .13
S x F 3 1. 22 0.41 0.08 .97
rr x S x F 3 0.64 0.21 0.04 .99
Error 112 610.30 5.45 ------------------------------------------------------------(*) p < .05
Table 12: Mean ALAX at 60 Newtons for the ACL Subjccts.
Table 16: Mean ALAX at 130 Newtons for the ACL Sub j C''-~u ••
Test Flexion Session HCùl1 S.D.
Active 60 1 7.10 <1. 1 Cl 2 7. Il 3.8'1
70 1 6.67 J • ~) 3 2 7.37 .\ . / /
80 1 6.::>1 J. lB 2 6.62 ,). JO
90 1 ~.90 2.69 2 6. Il 3. q 1
Passive 60 1 7.71 ·1 • ·1 ·1 2 6.99 ·1. ; ,)
70 l -J • 1 :: \ . ()~; 2 (, . 31! ·1. 1 -1
80 1 t 1.- .... ) ). )a .' •• )(1
2 ,) • () 1 ? JO
90 1 <1.5-; / . il (,
2 '1. "J 1 1 • 1 /
Collapsed cells Mean
Test Active 6.76
Passive G.O,) 1 • ,1 ()
Flexion 60 7.2-3 ,1 • 1 1
70 G.88
80 6.17
90 5.42 ,) . il J
Session 1 6.40
2
61
Table 17: ANOVA Results at 130 N for the ACL Subjects. ------------------------------------------------------------Source df SS MS F P ------------------------------------------------------------Test (T) 1 14.72 14.72 1. 04 .31
Figure 1: Knee Flexion and ALAX for the ACL Subjccts
,-_._------------------- ----- -- - -
• 0 Cf) (j) C
0
~ Q)
Z 0 Ct) ,-
,-(j)
0 'l> 0) (1)
~
0) CI) (1)
""'0 C "'-"" 0 C ~ 0 (}) X Z (1)
...) li. (i)
0 (1)
i (1) t'- c + ~
Cf)
C 0
~ (})
Z 0
0 (!) (!)
i • l
1
- -1 -,-----r-------r-- --- - - -1" ,
ex> t- <D L!) ~ (Y) C\J ,- a
(ww) X\flV
Figure 2: Knee Flexion and PLAX for the peL Subjects
-- ------- -----------,------
, ,
co ~I --~I ~---II---.I----II----~I----~
~ W ~ ~ M N ~ o (ww) X\fld
a 0)
u;a Q) <X) Q) -C>
Q) 'U -c o x Q)
Ua Q)
~ ~ ~
a w
63
en C o ~ Q)
Z o ('f') T"'"'
en c o j Q)
Z o 0)
t en c: o
~ Z o (0
5.1 Introduction
CHAPTER v
Discussion of the Results
It has been weIl documcntcd that posterio!" Cl"\ll'illtO
ligament disruptions cause an incn:~ase in poster i or k!lC'P
laxity scores (King et al., 1986) and can be best ::.hown whcn
the knee is examined at 90 degrees of flexion (Grood ct ~l.,
1988). On the other hand, anterior cruciatc Ugament injuL"ic~~
cause an increase in anterior knee laxity scores (M~rkolt 0t
al., 1978; 1984). This can be most clearly (~l icitocl \..;I1(>n tlw
knee is flexed from 20 to 30 degrees during application 01 tho
so called Lachrnan test (Gurtler et al., 1987).
However, él distinction bet\.,een ACL and PCL J iqùmont
injuries requires the establishment of a tibial neutra 1 po i nt,
from which tibial displacements can be referenced. F'rdrü: 1 in
et al. (1991) and Torzilli et al. (1981; 1984) omploYt>d !;trer~~;
radiographie techniques to compare norm.:ll anù cruci Lltc in) url·ri
knees. Using the KT-lOGO {MEDmetric, San Diego, CdJ ifornin),
Daniel et al. (1982; 1988) demonstrated that the Quadricoph
Active Test can oe used to diagnose poster ior crue i dt<..'
ligament disruptions and to measurc posterior laxity at the>
knee. Cannon and Lamoreux, in a persona l commun j Cd t i on
referenced by Anderson and Lipscomb (198 'J), suggcsted thù t
true posterior tibi al displacement could be determined by
placing the knee at 90 degrees of flexion and zero i ng the
65
stryker with the quadriceps contracted. This would enable the
examiner to determine if an instability could be secondary to
an anterior or posterior cruciate ligament in jury.
'l'he present investigat ion examined tibial displacement
values relative to the initial testing position of the tibia
in the sagittal plane during anterior-posterior assessment of
cruciate ligament injured knees on the Genucom Knee Analysis
Systen. Patients were submitted to active and passive
i1nterior-posterior knec drawer tests at 60, 70, 80 and 90
degrees ot flexion during two evaluation sessions. Laxity
scores wcre estimated at forces of 60, 90 and 130 Newtons.
5.2 Type of Test and Laxity in Cruciate Deficient Knees
Orthopaedic surgeons have usually assessed the integrity
of knee ligaments by measuring the arnount and direction of
tibial motion that results from manually applied forces
(Markolf et al., 1978). These are passive tests since the
displacing force is applied by the examiner. Another method
of assessing ligamentous and capsular integrity is to measure
the change in joint position which results from active
contraction of the patient's muscles. These are active tests
Binee the patient's muscles provide the joint displacement
force (Daniel et al., 1988).
At full extension, the patellar tendon lies anterior to an
imaginary reference line that is perpendicular to the surface
of the tibial plateau and passes through the tibial tubercle
1
(Muller, 1988). As the knee approaches flexion, the lemul"
rolls posteriorly on the tibia, guided by the (TUC L.ltt">
ligaments. The orientation of the patellar tendon c11Lll1qcs
continuously from anterior to posterior with respoct to the
reference line (Goodfellow et al., 1978). 'l'he resul ttlnt !:~l1e,ll'
force produced by the pull of the patellllr tendon on tll0
tibial tubercle changes from anterior to poster iOI' \-J i tl!
increasing flexion angle. In the normal knee, the crOG~~ovel'
from anterior to posterior shear occurs between GO ~nd 90
degrees. At this position, called 1:he quadd ceps I1[>Ut I"dl
angle, the tibia does not shi ft anterior l y or poster j or 1 y \-Jl!ell
the quadriceps muscles are contractcd (Dùn je l et él J ., 1 ') ~:rn .
In the ACL-def ic ient pi1t ient, i1nter ior sub] UXélt i on n j ttH'
tibia can be demonstrated during applicl)tion of the qu,Hlr i ccp:;
active test at 20 to JO degrees of knee flexion. 'l'his w,,:;
first demonstrated by Daniel et al. (1988) on the KT-l0()() ,lnr!
later achieved by Frankl in et al. (1991) who eJT1p] oyerJ d
quadriceps contraction technique to assess ACL j nsLüJ il j t i 0:;
through x-rays. This subI uxation occurs bccausc a qUùdr 1 cop:;
contraction beyond its neutral angle causes anterior tibial
displacement (Anderson and Lipscomb, 1989).
5.2.1 PCL Injured Patients
In 1988, Daniel ct al. reported on the uco of th0
quadriceps active test to determine posterior knee lnxity ~nd
PCL disruptions. Part of the sample included 24 patients with
67
unilateral chronic peL injuries. The testing instrument was
the KT-1 000. Tests were performed at 89 Newtons of force.
Their knees were tested at 30 degrees of flexion and at the
posi tian that had been determined ta be the quadriceps neutral
angle in the intact side. with the lower 1imb re1axed and the
knce in 90 dcgrees of flexion, the tibia shifted anteriorly on
contraction of the quadriceps in aIl but one of the 24 knees
thùt had a chronic rupture of the posterior cruciate ligament.
The subjccts had mcan posterior differences (involved minus
intact knecs) equal ta 2.1 mm during passive tests and 7.3 mm
during active tests, which were significantly different at the
.001 lcvel. The present experiment showed similar significant
diffcrenccs (p<.05) between active and passive tests at 90 and
1JO Newtons of force. Mean posterior differences (involved
minus intact knees) were 2.89 mm for active tests and 2.31 mm
for passive tests at 60 Newtons, 3.53 mm for active tests and
2.77 mm for passive tests at 90 Newtons and 4.12 mm for active
tests and J.11 mm for passive tests at 130 Newtons. A larger
sample might have provided enough statistical power to
dcmonstrate significant differences at 60 Newtons of force.
The values recorded for laxity in the present study may have
becn smaller since tibial rotation was lirnited when compared
to tests performed on the K'l'-1000. The resul ts of bath
experiments confirmed that a quadriceps contraction was able
to cause a signifj cant anterior shift of the tibia in peL
injured patients who had a previous posterior tibial sag prior
to the posterior knee drawer test.
5.2.2 ACL Injured Patients
The present experiment tested ACL patients betwecn 60 and
90 degrees of flexion. The ANOVA results revealed no
significant differences (p>. 05) between active and pilS~:::;i Vt>
tests at 60, 90 and 130 Newtons of applicd force. 'l'his (\grco~~
with results presented by Daniel et al. (1988). In theit' AC/,
injured patients, there was no more than one millimctrc 01
anterior translation after contraction of the quadr l Cepfj w i lh
the knee at 90 degrees of flexion with a force application 01
89 Newtons. This translation was not significant whon
comparing active and passive tests. Althouqh siqni 1 lL'ant
differences were not found in the present invcsUgation, it
can be observed that for the ACL subjects evaluated at 90 and
130 Newtons, there is more anterior tibial laxity for nctivc
tests. This supports arguments by Anderson and Li pscomb
(1989) that a quadriceps contraction with the kncc floy.c'rj
beyond the quadriceps neutral position, as mny have o('currerj
with some flexion angles employed in the> protoco] 01 thi:.
research (80 and 90 degrees), resul ts in po~~t('r j or
displacement of the tibia. This occurs due to the oricntiltion
of the pull by the patellar tendon. For the ACL sub-jccts, th'.'
tibia was shifted posteriorly after contraction 01 the
quadriceps muscles at angles of flexion beyond tt1C' quarJriccp',
neutral angle. 'fherefore, when an anteriorly di rectc'rj J Qild
69
was applied, more anterior laxity was recorded during active
tests, but not enough to elicit significant differences as
compùred to passive tests.
5.3 Flexion Angle and Laxity in Cruciate Deficient Knees
5.3.1 peL Injured Patients
In 1988, Grood et al. demonstrated that the amount of
posterior translation after the PCL was injured increased as
the knee was flexed, being greatest at 90 degrees. The same
observation was made in the present research. Posterior
tibial laxity showed the highest scores at 90 degrees of
flexion under GO Newtons (2.01 mm), 90 Newtons (2.15 mm) and
130 Newtons of force (2.69 mm). The results for the other
angles of flexion confirm the observations by Daniel et al.
(1988) with greater values for posterior tibial laxity at 60
as compared to 70 and 80 degrees of flexion. It is important
to note that an accurate determination of the quadriceps
neutral angle on the Genucom, as described for the KT-IOOO
(Daniel et al., 1988), was very difficult as the Genucom
goniometer is very sensitive to any slight modification in
knee angle or tibial position.
The fact that no significant differences were found among
knec flexion angles for the PCL subjects is illustrated in
Figure 2 (Chapter 4). This fa ct is also supported by the non-
significant ANOVA results (p=.84 for 60 Newtons, p=.77 for 90
Newtons, and p=.74 for 130 Newtons) and can be explained by
l two arguments.
70
First, the angles employed in the protocol
were not different enough to alter anterior-posterior tibial
displacement as theorized by Anderson and Lipscomb (1 9B9) •
The second argument stems from a l'PC re important observtl t ion by
Gollehon et al. (1987) and Grood et al. (1988). The tluthors
stated th3t both the posterior cruciate ligament tlnd other
secondary restraints are required to maintain rl normnl
anterior-posterior motion of the tibia, particu]arly nt knoo
flexion angles less than 45 degrees. This points out thnt the
secondary restraints play a more important role in stnbilizinq
tibial posterior laxity at angles that are ClOSE to extension
of the knee. These secondary restraints to posterior
translation are less effective when the knee ls evaIuéltod
between 60 to 90 degrees of flexion. Therefore, once the
posterior cruciate ligament is injured, tcsting postorior
laxity of the knee between 60 and 90 degrees of flexion ShC>llld
reveal similar values since slackness increases in the
secondary restraints which limit posterior tibial trélns]rltion.
According te Butler et al. (1980), these structure~~ art! the
posterior part of the lateral area of the capsule, the mollidl
area of the capsule, the collateral 1 igaments ~1l1d the meu i dl
area of the capsule.
5.3.2 ACL Injured Patients
Results from previous studies have shawn that as th0 kncc
flexion angle approaches extension, there is an incrcose jn
71
rccorded anterior laxity of ACL deficient patients (Butler et
al., 1980: Hosenberg and Rasmussen, 1984). This is in
agreement with the findings of the present investigation when
comparing ALAX across 60, 70, 80 and 90 degrees. It is
import<:mt to mention that the increase in ALAX is best
demonstrated at 20 to 30 degrees of knee flexion (Gurtler et
al., 1987). lIowever, these angles were not employed as part
of the protocol of this experiment.
A cJear trend in ALAX scores was observed in the present
reseal~h, as illustrated in Figure 1 (Chapter 4). As knee
f J c·/.! on angle increased, anterior knee laxi ty va J. ùes
clecreased, which agrees with previous tindings. HO\vE'ver, this
trend and the ANOVA results (p=0.08 at 60 Newtons, p=.13 for
90 Newtons, a:1d p=.23 for 130 Newtons) suggest that there
might have been a significant main effect for the variable
flexion angle if a larger nurrl'er of ACL deficient subjects
wore tested. Three arguments support the non-significant
finctings among flexion angles for the ACL subjects. First, at
f 1 ex ion angles less than the quadriceps neutral angle, a
quadriceps contraction previous to the anterior drawer brings
the tibia anteriorly through the pull of the patellar tendon
([)anip 1 et al., 1988; Anderson and Lipscomb, 1989) .
'l'herefore, decreased ALAX scores might have been recorded at
angles of flexion of 60 and 70 degrees. Second, the opposite
occurs when the quadriceps is contracted at 80 and 90 degrees
when the patellar tendon pulls the tibia posteriorly before an
"
"1 ;l
anterior force is app' 'ed. Therefore, an incrcascd anterlor
, axi ty might have beel -ecorded a t knce flex i on all91 c~, 0 1 ~~ 0
and 90 degrees during the active protocol. 'l'hird, ,\t the'
angles of f] exion employed in the protocol (w i th tl10 knpc
close ta flexion), the secondary rcstra i nts to [onv,) rd ti b i <11
displacernent were taut (Gollehon et al., 1987). 'l'his may hi1ve
decreased the magnitude and the variance recordcd [or scorc~;
of ALAX. According to Rovere and Adai r (l9BJ), tll('!;,
secondary restraints are the medjal col1atcr(1l 1jtJdrn0nt, tlw
retinacul um and the poster ior port ion 0 r tlw c;\ p~;\ll (' .
5.4 Reprod1'cib i li ty of Sess i ons on the GcntJ.t;PJTI
In 1985, Emery et al. found no significant dl t t ('/'('/W0';
between first and second testing sessions 01 dl [forent tc':;tcn;
for any anterior/posterior tests complcted on the G('I1IICO/TI.
Subjects had no injuries ta their knees. fIo jnlorrndti()l1 \·/d',
avail able regarding specifie resu l ts 0 f tria ls or' 1 C!ve 1:> 0 f
force that were used to calculate knee laxi ty. 'rests 'vIC rc
performed at 30 and 90 degrees of flexion.
Highgenboten an~ associates (1990) reported on results of
reproducibility testing of the GenUCOll. ':In 20 subjccb~ ',li th
intact knees. They found means and standard errar:: j or
anterior laxlty at 90 degrees of 7.92 mm and 0.51 mm in trial
1 and 8.01 mm and 0.47 mm in trial 2. A t-test for correlntcd
rneans indicated no significant differences (p<. 05) betvlcen any
of the pairs of the independent trials.
73 F
l Wroble et al. (1990) tested five males and five females
with no history of knee problems on the Genucom. Day-to-day
vüriabil i ty was not statistically signi ficant. Anterior-
postcdor drav/Cr tests were performed at 90 and 30 degrees of
flex jan w i th forces of 90 Newtons. In the same study, three
uni lateral ACL deficient subj ects were tested. The mean
diffcrence (involved minus intact knees) for anterior laxity
\-1i1S only O.G mm with a standard deviation of 4.0 mm. In the
present experiment, at 90 degrees of knee flexion with a force
of 90 Newtons 1 the T'lean difference was 3.64 mm wi th a standard
deviat ion of 1. 75 mm when combininq active and passive
protocols and sessions 1 and 2. These discrepancies in mean
differences may be explained by the larger sample size in the
present experiment.
The findings of the three previous experiments are in
agreement with those of this study. The day-to-day
I"oproducibility of the active and passive protocols on the
Genucom was statistically confirmed by non-significant ANOVA
rcsul ts for the session variable and no interaction of this
variable wi th the type of test or the flexion variables.
Howevcr, for bath samples of ACL and the peL injured
patients evaluated at 60, 90 and 130 Newtons 1 the resul ts for
scss ion 2 were always higher than session 1. Edixhoven et al.
(1987) in measuring test-to-test reproducibility observed a
cycle effect. The authors observed that the first test in a
sCnting was signif icantly smaller than subsequent tests after
! ,1
subj ects were instructed how to control the ir muscular st,1tus.
Wroble et al. (1990), testing on the Genucom, <lnd Riedcnn,ll1 et
al. (1991), testing on the Knee Signature System, ,\1 ~~0
identi fied a "learning effect". In the present expC' t' 1 I11pnt ,
the use of the Biostim 6010 holpcd sub:i cets to re l,lX tilt' i t"
hamstrings and to contract their quadr iceps musc l es. At t C' l'
the initial seating, sub j ects may have loa rned how to con t 1'01
thei"'::' muscular status which may have ùccounteù t 0 t" thl.'
increased laxity scores durlng the second session.
5.5 Levels of Force and Tibia l Dl êQli:tçc'n1çJ1t
Al though not a maj or focus of the present rese,) rch, t hr>
relationship between force application (60, 90 dnd 130
Newtons) and tibial laxity of the pel. and J\CL pdti('nL~
deserves sorne comment. It is important ta note that thes0
findings are limited by the facts that hJO different s,1mple~;
of ACL and peL subj ects were tested and these observat i om:, l'dl1
be applied only to the Genucom system.
Sherman et al. (1987) compared the ueLA device to the K'l'-
1000. In examining 48 normal and 19 ACL-deficient patients,
the ueLA device gave consistently lm-1er absolute disp1 ace-ment
readings than the KT-lOOO at the same displacement force (B~
Newtons). However, when the recommended displacement forcc of
200 Newtons was used for the ueLA apparatus, similôr
displacements were observed. These discrepancies wcrc
attributed to differences in device design. It is important
75
thilt standard procedures be fc·llowed when testing for knee
l ax i ty. In ùddi tian, the levels of force used ta measure
lûxjty should ùlways be reported.
Fukubayashi et al. (1982) observed that at high levels of
force (."ore than 90 Newtons), a greater standard deviation in
the displacements was found in ACL injured patients compared
ta PCL injured patients. This was a Iso observed in the
present experiment and was probably due to a greater
variabi li ty of secondary restraints that control for anterior
tibial displacement. It suggests that when PCL injured
p()ticnts perform active and passive tests, secondary
restrtlints come into play at low levels of force, \:hich does
Ilot occur in ACL inj ured subj ects. In the present study, this
is aIso supported by the fact that posterior laxity of the peL
p()ticnts at 60, 70, 80 and 90 degrees had smaller variability
than anterior laxity of the ACL patients when looking at the
three levels of force. This is illustrated in Figures 1 and
2 (Chapter4).
steiner et al. (1990) tested the anterior-posterior
displacement of the knee of 13 normal and 15 ACL injured
patients on the Genucom. The authors found that the
reproducibility of their measures and their diagnostic
correctness were similar at bath 89 and 133 Newtons of force.
The test variability was smaller at the higher force. This
does not agree with the results of the present study and with
those of Sherman et al. (1987). Forces higher than 89 Newtons
appear to be more appropriate for identi ficùtion of knoc'~-; th,\t
have a rupture of the anterior cruciate J leJLlI1lCnt.
other hand, low levels of force oppear to be s\lrricicnt tew
testing posterior laxity of peL injured subjects.
1
77
.\ CHAPTER VI
Summary, Conclusions and Recommendations
G.l Summary
'rhis cxperimcnt attempted to characterize cruciate knee
deficiencies using the Genucom system with two test starting
positions of the tibia: (1) neutral and (2) resting. A
qUùdr leeps active technique was compared to a passive protocol
ùt four angles of flexion of the knee: 60, 70, 80 and 90
degrees.
Eight ACL and eight PCL injured individuals with ages
rùnging from 16 to 37 years participated as volunteers in this
rcsea rch. For ACL patients, the cri terion for inclusion j n
this study was anterior tibial displacement equal or greater
than ] mm for the involved leg compared to the intact leg when
assessed at 60 degrees of flexion. For PCL patients, the
criterion for inclusion in this study was posterior tibial
displacement equal or greater than 2.5 mm for the involved leg
compared to the intact leg when assessed at 90 degrees of
flexion.
Subjects performed active and passiv~ anterior-posterior
knee drawer tests wi th both the invol ved and intact legs.
These tests were performed during two sessions to verify the
reliability of the procedures. posterior tibial displacement
values (laxity in mm) were measured at knee flexion angles of
60, 70, 80 and 90 degrees for PCL subjects. Anterior tibial
lH
displacement values (laxity in mm) wcrc measured at kncc
flexion angles of 6 0, 70, 80 and 90 degn~ûs for ACT. sub j cd:;.
Laxity .cores were estimated at force values of 60, 90 ~nd 130
Newtons tor both peL and ACL subjects.
A feedback un i t (Biostim 6010) was used to mon i tor
muscular contraction during application of the i1ct ive <1nd
passive protocols. Surface elcctrodes werc ,1ttilched to tlw
hamstr ing muscl es. The feedback un i t tlSS i ~> tell ttH' l'V.! 1 ucll (Il
to select tests \.Jithout contractions of cxtc>rndl mll~~CLlI ,thll ('.
The quadriceps muscles were contracted ùurinrJ tilt' <let iv('
protoeol and relaxed during the passive protoco1 .
Three trj aIs were performed for céleh type oL test, ~:,C':;';i()n
and angle of flexion. Mean di fferenees bet\'/0cn the i nvo 1 vl'd
and intact l eg were used for statist iC2l1 (1 na1 yscs. Ath 1 ("'('
factor ANOVA was performed ta test the hypothescs. '('he·
factors were: (1) type of test (active and passive), (?)
session (1 and 2), and (3) knee flexion angle (60, 70, 80 <1nd
90 degrees).
The first hypothesis stated that posterior knee 1 in: 1 ty
values for peL subjects would be similar [or actl vc dnd
passive tests at 60, 90 and 130 Nevltons. The ANOVA resu]t!;
showed F-ratios of 4.58 for 90 Newtons and 5.88 for 1 JO
Newtons, which were significant at the .03 and .02 lev!? l~;,
respectively. At these levels of force, postcrior laxity wns
significantly greater for active tests as compared ta passive
tests (p<. 05). At 60 Newtons, the ANOVA ShOvlCd an F-rat io of
3.56 (p=.06).
79
The use of a larger sample might also have
elicited significant difference between active and passive
tests at this level of force.
ln the second hypothesis, it was predicted that anterior
knee laxlty val ues for ACL subjects would be similar for
active and passive tests at 60, 90 and 130 Newtons. This was
confirmed by the ANOVA results, which revealed F-ratios of
0.97 (p=.33) for 60 Newtons, 1.19 (p=.28) for 90 Newtons and
].04 (p""'.31) for 130 Newtons.
The third and fourth hypothesis predicted that the values
[or posterior knee laxity of PCL subjects and anterior knee
laxity of ACL subjects would be similar for the two sessions
at 60, 90 and 130 Newtons. For PCL subj eets, the ANOVA
calculated F-ratios of 0.01 (p=.93) for 60 Newtons, 1.03
(p:...-.31) for 90 Newtons and 1.68 (p=.20) for 130 Newtons. For
ACL subjects, the ANOVA calculated F-ratios of 2.75 (p=.10)
[or 60 Newtons, 2.25 (p=.14) for 90 Newtons and 0.01 (p=.95)
for 130 Newtons. Therefore, the active and passive protocols
produced reliable results across two sessions.
The fifth hypothesis stated that the posterior knee laxity
val ues for PCL subjects would be similar for 60, 70, 80 and 90
degrees of knee flexion at 60, 90 and 130 Newtons. This
hypothesis was accepted at the .05 level as the ANOVA results
revealed F-ratios of 0.28 (p=.84) for 60 Newtons, 0.37 (p=.77)
for 90 Newtons and 0.43 (p=.74) for 130 Newtons. For the PCL
subjects, a trend in the data was not observed as illustrated
80
in Figure 2 (Chapter 4).
The sixth hypothesis predicted that antcrior kncC' l<1x i ty
values for ACL subjects would be similar for GO, 70, 80 dlHI ')l)
degrees of knee flexion at 60, 90 and 1 J 0 Newtons. '1'11(' F
ratios from the ANOVA were 3.25 (p=.08) for 60 Ncwtom" l.')}
(p=.lJ) for 90 Newtons and 1.44 (p=.23) for 130 Nc'wton:-'.
Al though the ANOVA resul ts did not show s ign if LCllnt
differences (p>. 05), a trend in the da té1 ex i stod dnd "-,d',
illustrated in Figure] (Chapter 4). A lùt"gcr Gl1mplf' ::1.'('
might have decreased the variability in antC'rior kncc I<1X i ty
and might have demonstrated significant differenccs LimOn,) the
four levels of knee flexion.
6.2 Conclusions
Considering the limitations and deI imi ttltj ons, th i s ~;hldy
justifies the following conclusions:
1. There was a significant anterior tibia l sh i ft in peL
injured patients when comparing active to passjvc tcstr;
performed from 60 to 90 degrees of knee flexion at forcc~;
ranging from 60 to 130 Newtons on the Genucom Knee Analysi~
System.
, 81
2. Therc was no significant anterior tibial shift in ACL
injured patients when comparing active to passive tests
pcrformed from 60 to 90 degrees of knee flexion at forces
ranging from GO to 130 Newtons on the Genucom Knee Analysis
System.
3. The Genucom Knee Analysis System produced rel iable
rcsults for two sessions when ACL and peL subjects performed
dctlve and pJssive tests at flexion angles of 60, 70, 80 and
00 dcgrees with forces of 60, 90 and 130 Newtons.
4. Posterior knee laxity of PCL injured subjects was
similar for knee flexion angles between 60 and 90 degrees at
levcls of force ranging from 60 to 130 Newtons.
5. Statistically, the resul ts showed that ACL inj ured
subjects had similar anterior knee laxity at flexion angles
between 60 and 90 degrees. However, a trend in the data
suggested that with a larger sample size this hypothesis might
have been rejected.
6.3 Recornrnendations
\' , L'.
The following recommendations can bc proposC'd 10r futul"l'
studies:
]. The effects of a quadriceps contraction on rotùUol1Lll
stability of the knee (cornbined rotation and ùnter iOl'-
posterior drawer) and on other joint flexion angles should b0
investigated.
2. It is suggested that the digi ti zat ion rout i no on t Il,.
Genucom be employed with active and passive protoco ls ta t('~.t-
its sensitivity and specificity to rneasure possible tibictl
shifts during the active protocol.
83
BIBLIOGRAPHY
Akeson, W.H., Woo, SL-Y., Amiel, D., Frank, C.B. (1984). The chemical basis of tissue repair: ligament biology. In: Hunter, L.Y., Funk, F.J. (eds); Rehabilitation of the Injured Knee. CV Mosby, st. Louis, p. 93.
Alexander, H., Nehmer, S., Parsons, J.R., Weiss, A.B., Pavlisko, F. (1989). Knee anterior stability measurements: manua l vs. knee ligament arthrometer. Transactions of the Orthopaedic Research Society, 2, p. 64.
Anderson, A.F., and Lipscomb, B. (1989). Preoperative instrumented testing of ùnterior and posterior knee laxi ty. The American Journal of Sports Nedicine 17, (3),387-392.
Arnoczky, S.P. (1983). Anatomy of the anterior cruciate ligament. Cl inical Orthopaedics and Related Research, 172, 19-25.
l\rnoczky, S. P. 1 Warren, cruciate ligaments. Ligaments, Churchill 195.
R.F. (1988). Anatomy of the In: Feagin, J.A. (ed); The Crucial Livingstone, New York, N.Y., 179-
Askew, M., Melby, A., Good, L., Baniewicz, F., Hurst, F., Boom, A. (1987). In vitro kinematic studies of n2mll, ACL def icient, and meniscectomized knees. 33rd. Annual Meeting of the Research orthoapaedic Society, January 19-22, ~an Francisco, Calitornia.
Baxter, M.P., Wiley, J.J. (1988). Fractures of the tibial spine in children - an evaluation of knee stability. The J011rna] oi Bone and Joint Surgery, 70-B, (2), 228-230.
Brien, IL, Hoshizaki, T.B., Lenczner, E. (1986). An evalulltion of four knee laxity testing procedures for crucillte ligament insufficiency. Unpublished Master' s Thesis. Department of Physical Education, McGill university.
Butler, D.L., Noyes, F.R., Grood, E.S. (1980). Ligamentous restraints to anterior-posterior drawer in the human kn e e . Th e Jou rn a l_o::::.=f--,Bo:<.o=...n:..::e=--=.!.a.!..On""d,--~J""o-=i~n~t=--~s~u~r:..:g=e-=r~yw',--~6~2,,----,A"-!.1 (2), 259-270.
Clancy, W.G., Shelbourne, K.D., Zoellner, G.B. (1983). Treatment of knee joint stability secondary ta rupture of the posterj or cruciate ligament. TJ19 __ Œournéll _Cl t Bone and Joint Surgery, 65-A, 315-322.
Clendenin, M. B., Delee, J. C. , Heckman, .J. J). (1980) . Interstitial tears of the posterior cruciatc ljgament 01 th8 knee. Orthopaedics~, 764-772.
Cooper, R.R., Misol, S. (1970) 'l'endon ,lI1d ligùmcnt insertion. A 1 ight and electron m icroscop i c study. The Journal of Bone and Jojnt SurgerY-~~~-A, 1-20.
Daniel, D.M., Lawler, J., Malcolm, L., Biddcn, E., O'Connor, J.J., Goodfellow, J. (1982). The quadriceps ;:1ntcrior-cruciate interaction. Orthopaed is§_.Tr<)J]l;iJ_c_t.LQI1.s J Jl, 199-200.
Daniel, D.M., Malcom, L.L., Loose, G., Stonr~, 1'1. L., ~;ilChs, R., Burks, R. (1985). Instrumentcd m()d~-;Uromcnt 01 anterior laxi ty of the knee. The Jouxn" l 0 f 1!0I1Ç> <l/HI Joint Surgery, 67-A, 720-725.
Daniel, D.M., stone, H.L. (1988). Diagnosü; ai kncc ligament in jury: tests and measurements of joint lioci~. In: Feagin, J.A. (ed.); 'l'he Crucial Lig_~!D.Çnj:..f~, Churchill Livingstone Inc., New York, N.Y., 287-100.
Daniel, D.M., stone, M.L., Barnett, P., Sachs, R. Use of the quadriceps active test to diagnose cruciate ligament disruption and mensure laxi ty of the knee. The Journéll _oX __ Jlon0 Surgery, 69-A, 386-391.
(1988) • postcrior posterio!"
i1nd ,J9Jnt
Danylchuk, K.O., Finlay, J.B., Krcek, ,ToP. (J9'l8). Microstructural organization of human and bovine cruciate ligament. Cl inical Orthopaedlc$~ ____ J JJ, 2')4-298.
Dye, S.F. (1988). An evolutionary perspective). In: FGélrJi " J .A. (ed); The Crucial Ligaments, Church i 11 Livingstone Inc., New York, N.Y., 161-17~.
Emery, M., Moffroid, M., Barman, J., Flcmjnq, IL, iIo'v/inrJ, J., Pope, M. (1989). Reliability of torc('/di~~pLlccrnont measures in a clinical device dcsign'....'u tu rneùsur c'
ligamentous laxi ty at the knee. __ Tbc __ ,!..c)~J_ŒQl_ 9J Orthopaedir:s and Sports Physical Ttg~rr;lpy.J._ .-LQ, (11), 441-447.
Biomcchùn ies of the The Cruçj 9J __ Ji) g~lm!?Dtê,
York, N. Y., 96-107.
Franklin, J.L., Rosenberg, T.D., PauIos, L.E., Frùncc, E.r. (1991) • Radiographie assessment of instùbi 1 j ty of tho knee due to rupture of the anterior cruciùtc ligament -a quadriceps-contraction technique. Thç ___ ,Lo~!YJ!~1l __ 9r Bone and Joint Surgery, 73-A, (3), 365-372.
Fukubayashi, T., Torzilli, P.A., Sherman, M.F., Wùrren, R.P. (1982). An in-vitro biomechanieal cvaluation of anterior- posterior motion of the knee. Tl1Ç~ __ .)_oJ.lrn~ l __ qL Bone and Joint Surgery, 64-A, (2), 258-76tl.
Furman, W., Marshall, J.L., Girgis, F.G. (lC)'/G). 'rhc anterior cruciate ligament. A function~l ùnalysis based on post-mortem studies. J'he .:[ol!X:_Jl,ll _ QJ !~OIJC'_ clll~l Joint Surgery, 58-A, 179-185.
Gardner, E., O'Rahilli, R. (1968). The early dcvolopment of the knee joint in stùged human embryos. ~1'1lC' ,JourD01 __ pf Anatomy, 102, 289-299.
Girgis, F.G., Marshall, J.L., Monajem, A.R.S. (19/S). 'l'he cruciate ligaments of the knee joint. Anatomic~l, functional, and experimental analysis. çJjJ::nÇ!..<.' L Orthopaedics, 106, 216-231.
Gollehon, D.L., Torzilli, P.A., War:en, R.F. (J'JB7). 'l'he role of the posterolateral and cruel atc ] lqùments in the stability of the human knee. L@ __ .J..9_lJXDJoll ___ 9.I_ H9[lg and Joint Surgery~9-A, 233-242.
Grood,E.S., stwers, S.F., Noyes, F.R. (1988). Limits of movement in the human knee. The \J ou rJl..é.lL __ 52 t __ UQ.TJ.Q __ .<Jl1td Joint Surgery, 60-A, 88-97.
Gurtler, R.A., stine, R., Torg, J.S. (1987). Ldchmiln test evaluated. Quantification of a clinical observation. Clinical Orthopaedics and Related ResearçhJ.-_2U, 141-150.
Highgenboten, C. L. (1986). The rel iabil i ty of thc: Gcnucom Knee Analysis System (abstract). Prc~~cntcrj at the Second European Congress of Knee _Surgcry ___ ~~~ Arthroscopy. Basel, switzerland, Septc~b0r 20th.
86
Highgenboten, C.L., Jackson, A., Meske, N.B. (1990). Genucom knee analysis system: reproducibility and database development. Medicine and Science in Sports and Exercisp., 22, (5), 713-717.
Hsieh, H-H., Walker, P.S. (1976). Stabilizing mechanisms of the loaded and unloaded knee joint. The Journal of Bane and Joint Surgery, 58-A, (1), 87-93.
Insall, J.N., Hood, R.W. (1982). Bone-block transfer of the medial head of the gastrocnemius for posterior cruciate insufficiency. The Journal of Bone ~nd Joint Surgery, 64-A, 691-699.
Iversen, B. F., Sturup, J. , Jacobsen, K., Andersen, J. (1989). Implications of muscular defense in testing for the anterior drawer sign in the knee - a stress radiographie investigation. The American Journal of Sports Medicine, 17, (3), 409-413.
Jacobsen, K. (1976) • Stress radiographical rneasurernent of the anteroposterior, medial and lateral stabili ty of the knee joint. Acta Orthopaedica Scandinavica, 17, 335-344.
Johnson, R.J. problem. li, 14-19.
(1983) . The anterior cruciate ligament Clinical Orthopaedics and Related Research,
Kennedy, J.C., Fowler, P.J. (1971). Medial and anterior instability of the knee. An anatomical and clinical study using stress machines. The Journal of Bone and Joint Surgery, 53-A,1257-1270.
Kennedy, .J.C., Weinberg, H.W., Wilson, A.S. (1974). The anatomy and function of the anterior cruciate ligament as determined by clinical and morphological studies. The Journal of Bone and Joint Surgery, 56-A, 223-235.
Kennedy, J.C., Hawkins, R.J., Willis, R.B., Danylchuk, K.D. (1976). Tension studies of human knee ligaments. Yield point, ul timat€:.. failure, and disruption of the cruciate and tibial collateral ligaments. The Journal of Bone and Joint Surgery, 58-A, 350-J55.
Kennedy, J.C., Alexander, I.J., Hayes, K.C. (1982). Nerve supply of the human knee and its functional importance. The American Journal of Sports Medicine, 10, 329-335.
87
King, S., Butterwick, D.J., Cuerrier, J-P. (1986). The ante ri or cruciate ligament: ~ rev iew of rûcent concepts. 'fhe Journal of Orthopaed iç'_._.<lD5L_~.P.QJ:.tJ! Physical Therapy, 8, (3), l10-122.
Kirk, R. E. (1982). Experimental Design - Proc~Q~lr..QE_.Jor tJJQ Behavioral Sciences. Wadsworth, Inc., Belmont, California, 2nd. ed, pp.144-145, 841-842.
Lipke, J.M., Janecki, C.J., Nelson, C.L. (1981). The role of incompetence of the anterior cruciate and laterù l ligaments in anterolateral and anteromedial instabil ity. The Journal of Bone and Joint Surger~Q_::lL 1015-1030.
Malcolm, L.L., Daniel, D.M., Sachs, R., stone, M.L. (198':». 'rhe measurement of anterior knee lax i ty t1 fter AC/, reconstructive surgery. Clinical OrtllOp0ol)ic[y, .l<)(),
35-41.
Markolf, K.L., Mensch, J.S., Amstutz, Il.e. (l()'/G). stiffness and laxity of the knee - the contrIbution~:; of supporting structures. Th~ourna LgJ . Hot1o "nd ,j 0 i nt Surgery, 58-A, 583-593.
Markolf, K. L., Graff-Radford, A., Amstutz, Il. C. (1 cn B) . ln vivo knee stability. A quantitative assessment using ~n instrumented cl inica 1 testing apparatus. Thil _~J Q~j n]a) .0 f Bone and Joint Surgery, 60-A, 664-674.
Markolf, K.L., Kochan, A., Amstutz, H.C. (198'Î). Measurement of knee stiffness and laxi ty j n pat i ont s with documented absence of the anter lor crue i fit" ligament. The Journal of BQne anQ.....J91..nt )~llrg0t'YJ ()()-A.,
242-252.
Marshall, J.L., Arnoczky, S.P., Rubin, H.r·1" vJjcUovdc7., T. L. (1979) . Microvasculature of the crue iL! te ligaments. The Physician and Sports MerLlçLrlr::' 1_.2, 81-91.
Mazet (1986). France.
McQuade, K.J., Crutcher, J.P., sidles, J.A., Lélrson, R.V. (1989). Tibial rotation in anterior cruciate deficicnt knees: an in vitro study. The Journal 9f_9r.t.boPilQ_(JJ.IT! and Sports Physical Therapy, 11, (4), l'ÎC,-149.
88
Muller, W. (1983). The Knee: Form. Function and Ligament Reconstruction, Sp~inger, New York, N.Y., p. 123.
Muller, W. (1988) . Kinematics of the cruciate ligaments. In: Feagin, J .A. (ed); The Crucial Ligaments, Churchill Livingstone, New York, N.Y., 217-233.
Noyes, F.R., (1974). failure. mechanics and Joint
Torvik, P.J., Hyde, W.B., and DeLucas, J.L. Biomechanics of anterior cruciate ligament An analysis of strain-rate sensitivity and
of failure in primates. The Journal of Bone Surgery, 56-A, 236-253.
Noyes, F.R., Keller, C.S., Grood, E.S., Butler, B.L. (J934). Advances in the understanding of knee ligament inj ury repair and rehabilitation. Medicine and Science in Sports and Exercise, 16, 427-443.
O'Connor, J.J., Goodfellow, J,W., Young, S.K. (1985). Mechanical interaction between the muscles and the cruciate ligaments in the knee. Orthopaedics Transactions, 9, 271.
O'Donoghue, D.H. (1959). Surgical treatment of injuries to ligaments of the knee. The Journal of the American Medical Associati~169, 1423-1431.
Oliver, J.H., Raab, S. (1984). A new device for in vivo the Genucom Knee Analysis Inc., Montreal, Quebec,
knee stabili ty measurement: System. FAR Orthopaedics Canada, Newsletter, 1, 2.
Oliver, J.H., Coughlin, L.P. (1987). Objective knee evaluatioll using the Genucom Knee Analysis System clinical implications. The American Journal of Sports Medicine, 15, (6), 571-578.
Riederman, R., Wroble, R.R. (1991). Reproducibility of the Knee Signature System. The American Journal of Sports Medicine, 19, (6), 660-664.
Rosenberg, T.D., Rasmussen, G.L. (1984). 'l'he function of the anterior cruciate ligament during anterior drawer and Lachman's testing. The American Journal of Sports Medicine, 12, (4), 318-322.
Rovere, G.D., Adair, D.M. (1983). Anterior cruciate-deficient knees - a review of the literature. The American Journal of Sports Medicine, Il, (6), 412-418.
89
Schultz, R.A., Miller, D.C., Kerr, C.S., Micheli, L. (1984). Mechanoreceptors in human cruciate ligaments. A histological study. The Journal of Bone and _JQlntSurgery, 66-A, 1072-1076.
Sherman, O.H., Markolf, K.L., Ferkel, R.D. (1987). Measurernents of anterior laxity in nor~al and anterior cruciate absent ~nees with two instrumentcd te~t devices. Clinical orthopaedicsL-215, 15G-161.
Shiavi, R., Lir..~ -ri, T., Frazer, M., Strauss, 11.., Abrarnovitz, J. (1987). Helical motion of the kncc -II. Kinematics of uninjured and injured knces dur i nq walking and pivoting. The Journal of Biom~chmLLL=~ 1 ;)0 , (7), 653-665.
Shino, K. Ohta, N., Horibe S., Ono, K. (1984). rn VIVO
measurement of A-P instability in the ACL-di!3nlptrd knees. Transact ions of the QCtJl0P0(-'(;:l i c _ f{or;c'd n'h Society, 't, 394.
Staubli, H.U., Jakob, R.P. (1990). posterior instùbility nf the knee near extension. A cl inicd l,mL! stressradiographic analysis of acutc inj u ries 0 [ the posterior cruciate 1 igament. The Journ~LÇ>J: _J}QrJ0 .'Incl Joint Surgery, 72-B, 225-230.
Steiner, M.E., Grana, W.A., Chillag, K., Sche]berg-KL)rnc~" 1:. (1986). The effect of exercise on anterior- postcrior knee laxity. The American Journrtl __ Qf __ SpoItÇ; MN] Icin r , li, (1),24-29.
Steiner, M.E., Brown, C., Zarins, B., Brownstein, B., Kov,ll, P.S., stone, P. (1990). Measuremcnt of ùntcriorposterior displacernent of the knee. A comparlson of the resul ts wi th instrumented devices and w i th cl j n i Cd 1 examination. The Journal of Bone and J_Q1Dt _ ~u.rgpry 1
72-A, (9) 1 1307-1315.
Sullivan, D., Levy, LM., Sheskier, S. (1984). r1edi,ll restraints to anterior-poster ior knce motion. 'l'hr> Journal of Bane and Joint Surgery~_~-l\, 930-93G.
Torg, S.S., Conrad, W., KaIen, V. (1976). ClinicdJ diagnosis of anterior cruciate ligament instability in the athlete. The American Journal of Sports M0dicinQJ .i, 84-92.
Tortora, G.J. (1989). principles of Human Anatomy. Harper & Row Publishers, Inc., New York, N.Y., 212-213.
90
Torzilli, P.A., Greenberg, R.L., Insall, J. (1981). An in vivo biomechanical evaluation of anterior-posterior motion of the knee. Roentgenographic measurement technique, stress machine, and stable population. The Journal 0 f Bone and Joint Surgery« 63-A, 960-968.
Torzilli, P.A., Greenberg, R.L., Hood, R.W., Pavlov, H., Insall, J. N. (1984) . Measurement of anteriorposterior motion of the knee in injured patients using a biomechanical stress technique. The Journal of Bone and Joi~t Surgery, 66-~ 1338-1442.
Van Dommelen, B.A., Fowler, P.J. (1989). Anatomy of the posterior cruciate ligament - a review. The American Journal of Sport-s Medicine. 17, (1), 24-29.
Walker, P.S., Wang, C-J., Masse, Y. (1974). Joint laxity as a criterion for the design of condylar knee prosthesis. proceedings of Conference on Total Knee __ Replacement, London, England.
Welsh, R.P. (1980). Knee joint structure and function. Cljni~qL Orthopaedics and Related Research, 147, 7-13.
Wroble, R.R., Grood, E.S., Noyes, F.R., Schmitt, D.J. (1990). Reproducibility of Genucom knee analysis testing. The American Journal of Sports Medicine« 18, 4, 387-395.
APPENDIX 1 Informed Consent Form
<)1
PROJECT TITLE: Laxity and the Tibial Neutral position in Cruclate DcficiC'nt KnC'C'~;.
PRII',CIPAL INVESTIGATOR: \vagn~r Cdlio Batista, M.P. Department of Phys 1 cal EcluL',\ t ion MCGlll UniversIty
The above mentioned study is designed to ev,l1ucltt' tW(l protocols, the anterior drawer test with and without- the influence of the quadriceps muscles using the Genucorn system.
Your invol vernent in the study requ ires pa rt ie i pa t j on i 11
two separate but identical testing sess ions w.i th the pr 1 ne i pd 1 investigator. One session will last about :3 0 to ,l'i ml IlU te:;. During the sessions, the investigator will conduct rndnudl nI)!)
invasive clinical tests on your knees usinq the Gf>Illll'O!11 1:11('('
Analysis System. First, nine points, l11cl r}.cd It/ i th ,1 p(·n, VIII 1 be digitized on your skin usinq i1n C'1(·ctroqonl{)Jl1r'tc.!. Electrodes from a bio-feedback un i t w il 1 be dt t,wh('<1 t () t Il!' thigh to monitor the contraction act l vi ty 01 th" mu';, -II",. IJn electrical current or radiation wi Il be employed. {nu 'vI i ] 1 !JI' required to sit on the system's chair ùnd rcLJx yOlll ] ()vJ01
limb muscles while the tests are being donc. II'h('Il, the investigc. tor wi Il ask you to hold your 16g at a spPC l 1 1 (' d nq l '-' for a short period while the tests are applicd and th., I)oint', are digitizcd. You \vill be allowcd to rcst bctlt/(lon :;r",:;I()I)'.
and tests as the achievement of fùt igue l s not i ntî>n<!('r!. '1'1)
restrain thigh movE'luents, thrl"'c c] amps wi Il bl"' lI::,od tl) ':r'f lIr-('
a fixed position. Every effort will be made tu conduct tl1P t,.':.t:: III ',1/1'11 .t
way to minimize an)' di scomfort. A report of the knce cVùluùtion::; vd 11 b(> rH-ovldc,rj t () jOli
and your physic ian. The data coll ccted W l 11 be ~:('pt 111 Oll tlab without indication of the subject' s namc. You m':ly dl;-;u discontinue your participation in the stucly ilt ùny t 1 me <lnrJ ask to have your resul ts destroyed.
If you understood this consent form clnd c\cccptod tn participate in the proj ect, pleasc s ign below. Jf you hd \l(' any questions about the study you can reach me at ('.;111) ;r,')-3244.
Signature ______________________________ _
Date ______________________________________________ _