Transverse Rotation of the Segments of the Lower Extremity in Locomotion

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1948;30:859-872. J Bone Joint Surg Am.A. S. Levens, Verne T. Inman and J. A. Blosser

EXTREMITY IN LOCOMOTIONTRANSVERSE ROTATION OF THE SEGMENTS OF THE LOWER

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TRANSVERSE ROTATION OF THE SEGMENTS OF THE LOWER

EXTREMITY IN LOCOMOTION *

BY A. S. LEVENS, M.S., C.E., BERKELEY, VERNE T. INMAN, M.D., SAN FRANCISCO, AND

J. A. BLOSSER, M.D., BERKELEY, CALIFORNIA

Iro,,o the �‘ni�er,sity of California, College of Engineering, and Division of Orlhopaedic Surgery, ,lfedical Scho3l

A complete analysis of human locomotion is difficult. The fact that persons walk and

run with apparent ease, and without conscious effort, does not. imply that. the mechanisms

employed are simple or readily understood. A comprehensive study of locomotion includes

not only analysis of the movements of the various segments of the body, but also the con-

relation of these movements with force studies and muscle action. Consideration of a prob-

1cm of such complexity suggests that delimitations are necessary, and the present study

endeavors to present. but one component. in the displacement pattern of the low’er cx-

tremity.

Many investigators have reported their findings with regard to the movements of

the various segments of the body, as projected upon the parasagittal plane. Few’ have

described the motions projected onto the frontal plane. It is doubtful that any previous

observers have attempted to measure the transverse rotatory motions of the various seg-

ments of the low-er extremity, as projected upon a horizontal plane. It is conceivable that

little attention has been given to transverse rotatory motions, possibly because motion in

the parasagittal plane has usually been regarded as a more significant act-ion in human

propulsion.

Present indications are that transverse rotations of the various segments of the low’cr

extremity are an important factor in the ease and rhythm of walking of normal individuals.

In order to improve function, reduce fatigue, and prevent more or less continual abrasion

at critical points on the stump of the amputee, provision in the prosthesis for allow-ing

transverse rotations of the same order of magnitude as those in normal legs may be a major

contribution toward the improvement of artificial legs.

Transverse rotations, as discussed herein, refer to angular d!isplaccments of the

various bone segments of the leg about their longitudinal axes. Results are presented of a

study of these movements in twenty-six normal individuals, tw’elve of �t’hom provided

completely satisfactory data.

The primary objectives in this study were:

1. To determine the magnitude of transverse rotations of the segments of the low’cn

extremity, and their relative transverse rotations with respect to each other.

2. To formulate ideas for design with regard to artificial limbs.

TECHNIQUES

Placenient of Pins

Stainless-steel threaded pins, 2.5 millimeters in diameter, were drilled firmly into the

contices of the various bony prominences adjacent to the hip and knee joints, sterile pre-

cautions and local anaesthesia being used. Targets, each consisting of a light w-ooden rod

w’it.h spheres attached! at tw-o points, w’ere fastened to the pins. Figure 1 shows pins No. 1,

No. �&, and No. 3, placed in the iliac crest of the pelvis, in the adductor tuberele of the

femur, an(! in the upper portion of the tibia (tibial tubercle), respectively. The insertion

* In So’ptember 194�5, a research project on prosthetic devices was undertako’n at. the Univo’rsity of

(‘alifornia, supervised by Professor H. D. Eberhart of the Civil Engineering Division. The work was initi-ated by the National Research Council, at. the reQuest of the Surgeon General of tho’ Army. The nationalprogram is directed by the Committee on Artificial Limbs of the National Research Council.

�‘OI,. 30-A, NO. 4, OCTOBFR 194$ 85�

Flo;. 1

Fmu. 2

Fig. 1: Subject with limls and targets attached.Fig. 2: Arramigemiient for recording pin-study data. (Re-

produo’ed, liv J)crn)issiomi, fromu Populer �Scien.ce Monthly,page 82, July 1947.)

S6() A. 5. LEVENS, V. T. INMAN, AND J. A. BLOSSER

TilE JOURNAL (IF BONE AND JOINT SUR(;ERY

of pin No. 2 into the medial sidle of tile femur ��‘as dict-atco! by the fact that placement.

fm’om tile iat.eial aspect so restricted movement of the iliotihial tract. that motion at the

knee ��-as suppressed.

( ‘OlleCt’iofl of Data

A photographic t’ccoro! o�1 the movement. of tile targets w’as obtained by three syn-

(‘11 ronizc(l 35-millimeter motion-picture cameras, operating at forty -eight frames per

second, with a shutter speed of 1, ‘96 second!, orientc(l at- distances of twenty-five feet from

the siibjO’(’t. The cameras were so located as to refer the targets to three mutually penpen-

oli(’ular (‘o-o)r(!inate ncfcrcn(’c planes ( Fig. 2 ) . Iti this mannel’ top, front , and side views of

the sul)jcct ��‘crc obtaine(l simultaneously. A clock mechanism made it possible to identify

related frames , \Vhi(’ll we ii’ studied from enlarged! proj ectcd images.

Reduction of I)ata

The first method employed in the reduction of data made use of computed space

co-ordinates of the targets. This ��-as felt necessary to correct for possible errors due to

perspective amid parallax. Later it was found that. in certain cases the values of the anglesbetween pins, ol)tamed from orthogonal projections, compared quite favorably with values

obtained from measurements taken directly from the photographs, showing the projections

U�OI1 the horizontal plane only.

Further study show’ed that. if the pins is’ene set horizontally or within 10 degrees of

horizontal, the angle between the pins, read directly from the photographs show’ing hori-

zontal projections, yielded! results that were w’ithin 2 degrees of the true values for the

middle 60 per cent. of the stance phase; the maximum variation between values obtained

by the two methods was 5 to 6 degrees at the instant of toe-off. Phase relationships were

not affected by the results obtained from the tw-o methods. The differences between

computed values and those obtained directly from the motion-picture frames were

not significant, since the variations were less t.han the variations among the individuals

tested.

Subject Age(Years)

Weight Height It’niarks

(Pounds) (Feet) (Inches)

2

3

4

6

7

8

9

10

ii

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

2728

29

24

27

40

21

19

26

20

25

21

21

27

24

23

23

27

21

23

282823

26

23

2519

27

21

THE SEGMENTS OF THE LOWER EXTREMITY IN LOCOMOTION 861

VOL. 30-A, NO. 4. OCTOBER 1948

TABLE I

DATA ON AlA, SUBJECTS* FROM PIN STUDIES

185 6 4

150 6 2

180 5 9

168 5 11�2

160 6 0

150 5 10

160 .5 1132

162 6 1

165 5 11

175 6 l3�

152 5 11

165 5 10

175 6

170 5 9

152 5

180 6

145 5140 5

175 5

200 6

145 5

180 6

182 6

160 5

135 5

160 5

Mo’chan;cal difficulties; 110 olata

One pin only; no dataPins miot set properly; ono’ Pill bemit

Excessive pin vibration




Satisfactory data

Gait affected by pins; no data

Pin loosened; 110 runs made

Satisfactory dataSatisfactory (lata

Satisfactory data

Satisfactory data

Below-the-knee amputee; no pi�is

3 Satisfactory data

2 Bad limp; pain; mio data

Bilateral amputo’e; 110 pins

Above-the-knee amput-co’; 1101 pillS

93�2 Limping; one leg short

6 Removed pin No. 1; paimi

8 Tibial pimi No. 3 broken

7 Satisfactory data

83� Satisfactory data

0 Satisfactory data

1 Pin No. 2 worked looso’

11 Satisfactory data

10 No comriplo’to’ usable o’yo’io’

7 I)ata 110)1 reduce:1

*Tii.o,Iit.�,_5ix mio)rnial sul)jects and three aliih)utc’es.

Test Results

Twenty-six normal subjects, varying in age from nineteen to forty, i�’ere studied.

No data were obtained from the first seven subjects because of excessive pin vibration,

bending of pins, single pin settings, and mechanical difficulties. Of the remaining nineteen

subjects, the data from seven i�’ere not used for the reasons shown in Table I. Tw’elve of

the subjects were considered satisfactory for study and analysis. The pin data obtained

from the photographs w-ere plotted on a rectangular co-ordinate system, in w’hich the

horizontal axis represented time in seconds and t.he vertical axis represented transverse

notation in degrees.

Complete analysis has been made only of the data dealing w’ith the top view, in

straight. and level walking. Data dealing with front and lateral views, in straight and level

walking, will be presented in subsequent publications.

Discu-snion of Curves

Curves obtained from motion-picture records of twelve normal subjects performing

straight, level w’alking, as viewed from above, show-ed the same general pattern of action,

although the magnitudes of inward and outw’ard transverse rotation varied in individual

cases.

Detailed study and analysis of individual and composite curves of all subjects (Fig. 3)

had to he based on the action of both legs, since the significant. changes occurred with nela-

THE Jt)t’RNAL OF HONE AND JOINT SURGERY

862 A. S. LEVENS, V. T. INMAN, AND J. A. BLOSSEII

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THE sE(;MENTs OF THE LOWER EXTREMITY IN LoCOMoTIoN 563

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864 A. 5. IJEVENS, ‘I. T. INMAN, AND J. A. BLOSSER

TABLE II

RANGE OF TRANSVERSE HTArmoN

Po’lvis-Pin No. 1 l�’mniir-Pin No. 2 Tibia-Pili No, 3

Subject (Degrees) ( I)egrees) (I)egrees)

8 8.0 17.6 25.6

11 9.8 9.6 16.4

12 4.0 10.2 23.0

13 - 4.7 15.0 15.0

14 10.0 17.2 19.6

16 7.2 9.8 13.4

21 Notin 24.8 22.8

23 8.4 18.0 15.0

24 3.0 14.0 17.0

25 7.4 8.6 17.4

26 9.4 Loose 21.4

27 13.3 23.3 24.1

Maximum 13.3 24.8 25.6

Minimum 3.0 8.6 13.4

Average 7.7 15.3 19.2

tion to positions of each leg. The following leg positions proved to he of salient importance:

1. Toe (of extremity with pins) leaving the floor;

2. Foot. of sw’inging leg abreast of other foot;

3. Heel (of extremity with pins) striking the floor;

4. Foot fiat, other foot at toe-off;

5. Foot flat and abreast of other foot;

6. Heel (of extremity with pins) rising and heel of other foot- striking.

rrh time during ivhich the foot is in space is the swing phase, and the time d!uning

w-hich any part. of the foot is in contact with the floor is the stance phase. These two phases

comprise a w-alking cycle of one extremity.

From the time the foot of the pin-loaded extremity leaves the floor (toe-off), until the

moment it comes abreast of the other foot, the pelvis, femur, and tibia have start.e(l the

cycle of inw’ard rotation. At the time the feet. are abreast of each other, there is a definite

increase in the rate of rotation of the femur and the tibia. As the swinging leg continues to

move forward, there is considerable increase in inw’ard rotation until the heel strikes the

floor, and then a rapid increase until the other foot leaves the floor. At the peaks of the

curves, the pin-loaded extremity receives the full weight of the body. This period then,

from the time the foot leaves the floor until the full weight of the body is on the foot, is

characterized by inward notation of all segment-s (pelvis, femur, and tibia), the distal pants

rotating more than the proximal ones. Beyond this point, outward rotation of all segments

takes place until the foot of the pin-loaded extremity again leaves the floor; and is related

to the period of increased forward and upward acceleration of the body. Here again, the

distal segments rotate more than the proximal ones. In addition, the more significant

features of t.hese curves are related to weight-bearing, in that inward rotation starts with a

minimum of w-eight-bearing and terminates w’ith full weight-bearing, w’heneas outw’and

rotation starts i�-ith full weight-bearing and ends w’ith minimal weight-bearing. Rotation

of the tibia is momentarily suppressed just as the heel-striking position is reached, while

the pelvis and femur continue inward rotation. Tibial rotation is again suppressed just

before the heel-rising position, while the pelvis and femur continue outward notation. This

is show-n in Figure 5-A for a single subject.

The magnitude and time of occurrence of the transverse rotation of the femur on the

THE JOURNAL OF BONE AND JOINT SURGERY


TABLE III

RELATIVE TRANSVERSE ROTATION AT Hm� AND 1�NEE JOINTS

DURING STANCE PHASE

Subject Fo’mmmr with Respect to Pelvis

(Degrees)

Tibia with Respect to Feniur

(Degrees)

8 7.4 8.2

11 6.3 12.0

12 8.6 11.1)

13 10.1 6.2

14 7.4 6.6

16 6.4 9.4

21 Pin No. 1 out 8.8

23 11.4 6.4

24 10.3 9.0

25 4.9 13.3

26 Pin No. 2 loose Pin No). 2 loose

27 11.1 4.1

Average 8.4 8.6

Stamidard deviation ±2.5 ±2.7

tibia are of particular interest to the clinician, for they are no doubt related to the locking

mechanism of the knee. When the knee is locked, inward notation of the femur occurs; and!,

in unlocking the knee, outw’ard notation takes place. Normally the knee locks and unlocks

twice in a-n average w’alking cycle, once during the last portion of the sw’ing phase and

again near the end of the stance phase. This action is’as cleanly show-n in high-speed motion

pictures of a number of normal subject-s. Cadence alt-ens the degree to w’hich the double-

locking action occurs, in that during slow’er rates of w’alking the knee tends to remain

ext-ended during the entire stance phase. The double locking is more apparent in the fast-er

cadences.

Ranges of transverse notation of the pelvis, femur, and tibia, as well as the maximum,

minimum, and average values in each case, are shown in Table II. These values were

obtained from the individual curves. While the magnitudes of transverse rotation vary

ill individual cases, it is of importance for the designer of mechanisms and for the clinician

tO) have a concept. of ranges of these motions and �ie average values. Curves for a single

subject are show-n in Figure 5-A. The general pattern is similar to that of the curves shown

in Figure 3. As previously mentioned, however, the knee-locking effect is shown more dis-

TABLE IV

MAGNITUDES OF TRANSVERSE ROTATION OF THE PELVIS, FEMUR, AND TIBIA *

Transverse Rotation

Member Range Average

(Degrees) (Degrees)

Relative Transverse Rotation

Members Rango’ Average

(Degrees) (Degrees)

Pelvis 3.0 to 13.3 7.7

Feniur 8.6 to 24.8 15.3

Tibia 13,4 to 25.6 19.3

Tibia with respect 4.1 to 13.3 8.7

to femur

Femur with respect 4.9 to 11 .4 8.4

to pelvis

* Complete data are shown in Tables II and III.

VOL. 31-A, NO. 4, OCTOBER 1948

NOIi�V1Od

THE JOURNAl. OF BONE AND JOIINT SURGERY

866 A. 5. LE�’ENS, V. T. INMAN, AND J. A. BLOSSE1(

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Relation of rotation, in degrees, to percentile rank (during stance phase).

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868 A. S. LEVENS, V. T. INMAN, AND J. A. BLOSSER


tinctly in the tibia! curve. Note particularly the flattening of the curve near the heel-

striking an(! the heel-rising positions of the stance phase.

While it is important to know’ the ranges of transverse rotation of the p’lvis, femur,

and tibia, it is even more significant to learn of the magnitudes of relative notations of the

femur w’ith respect to the pelvis, and of the tibia w-ith respect to the femur, since such

value�s may have a bearing upon the design of artificial limbs, as w’ell as upon the functions

of the joints from a clinical point of view-.

Composite curves for all subjects, showing relative transverse notations of the tibia

w’ith respect to the femur (knee joint) and of the femur with respect to the pelvis (hip)

aie presented in Figure 4. In the former instance there is practically no relative rotation

during the period from the feet-abreast position to the locked-knee position of the swing

phase, and relative inward rotation of approximately 3.5 degrees occurs between the

locked-knee position and the full weight-bearing posit-ion. Beyond this point there is a

slight outward relative transverse rotation of approximately 1.5 degrees, during the in-

t-erval from the full weight-bearing position to the time flexing at- the knee occurs. This is

followed by a very slight mw-and rotation of about 0.5 degree, after which there is a marked

relative outward rotation of approximately 3.5 degrees as the foot reaches the toe-off

position.

The relative rotation of the femur with respect to the pelvis is also of considerable

interest. Throughout the period from minimal load to full weight-hearing, inward notation

of approximately 7 degrees occurs. From the fill! u-eight-bearing position to the toe-off

position, outward rotation of about 6.5 degrees takes place. It. should be reiterated that

this discussion of results deals only with transverse rotatory motions of the various seg-

ments of the low-en extremity, as projected upon a horizontal plane, and only for the cases

covering straight and level w’alking.

In all subjects, the average relative notation of the tibia with respect to the floor w’hen

the foot is fixed on the floor-that is, during the major portion of the stance phase-may

be obtained from the tibia! pin curve. The magnitude of the relative rotation is approxi-

matelv 7 degrees mw-and, during the interval from 7 per cent. to 17 per cent. of the walking

cycle ; and it is approximately 8 degrees outward in the interval from 17 pen cent. to 43

per cent. of the w-alking cycle (Fig. 3).

Ranges of relative transverse rotation of the tibia with respect to the femur and of the

femur wit-h respect to the pelvis, as well as maximum, minimum, and average values for the

individual cases, are show-n in Table IV. Here again, variations exist in the magnitudes of

relative transverse rotations for the individual cases. A know’ledge of the possible ranges

and average values is of significance to both designer and clinician, since such information

w’ill he helpful both in developing mechanisms for the improvement of artificial limbs and

in a bet-ten understanding of locomotion.

Figure 5-B shows the relative transverse rotations at the knee and hip joints of one

subject. During the stance phase, in the interval from the heel-striking position to the

feet-abreast position, very little transverse rotation of the tibia with respect to the femur

takes place (about 1 to 1 .5 degrees) . As the knee locks, relative rotation increases inw-ardly

about 2.5 degrees, follow-ed by a rapid outward relative rotation of about 4 degrees as the

knee flexes to the toe-off position.

During the interval from the heel-striking position to the foot-flat position of the

stance phase, the relative transverse rotation of the femur with respect to the pelvis is

about 10 degrees inward, follow-ed by a shorter interval from the latter position to the

feet--abreast position, during which the relative rotation is about 2 degrees out-w-ard. This

action is then followed by mw-and relative rotation of about 2 degrees, during the interval

from the feet--abreast position to the heel-rising position. From this point- on, fairly rapid

outw’and relative rotation of approximately 10 degrees occurs as the toe-off position is

reached.

VOL. 30-A, NO. 4, OCTOBER 1948

870 A. 5. LEVENS, V. T. INMAN, AND J. A. BLOSSER

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VOL. 30-A. NO. 4, OCTOBER 1948

‘l’he relation to percentile i’ank of the relative rotations of the iemui’ with t’espect to

the pelvis, a.I1d of the tibia with iespect to the femur, is show’n in Figure 6. ( )m’olinate values

represent percentages of SuI)jects having magnitudes of Iotation less than the values shown

by the corresponding abscissae. The points for both cases-femur with respect. to pelvis

and tibia w’ith respect to femur lie �-eny nearly on straight lines, indicating a normal

dist nil)iltiOIi pattern.

A sti’iking demonstration of relative transverse notation betw’een tile tibia and femur

at the knee joint is show’n in Figures 7-A and 7-B. The angular dhsplacement caused by the

change from the flexed position of the leg to the fully extended position is cleally seen in

the angular change between the targets.

SUMMARY AND CONCLUSIONS

TraIlSvel’se rotations of the pelvis, femur, and tibia occur in all normal individuals

(Table IV). Inward and! Outward! rotations of the segment-s are relate(l to weight-hearing.

Inward rotation takes place during the phase from minimal w’eight-i)eaning to full weight-

bearing, and outward rotation occurs (luring the phase from fill! weight-bearing to minimal

load.

The ro(ations of the low-er extremity appear to be absorbed in the articulations of the

foot and their related ligamentous structures.

Restrictions placed! upon the normal transverse notations will, to varying degrees,

modify the synchrony an(! rhythm of walking. The awkwardness an(l discomfort of a

patient., required to wear a leg brace w-hich does not provide for these rotations at the hip.

knee, and foot., are no doubt due, in pant., to the restriction of these motions.

At. the present time no prosthesis for t.he lower extremity has purposely incorporated

mechanisms to provide for transverse rotatory motions, except on an experimental basis.

Suppressing this rotation prevents the prosthesis from approaching t.he behavior of a

normal extremity, and thus requires alterations in the normal pattern of movement of the.

872 A. 5. LEVENS, v. T. INMAN, AND J. A. BLOSSER

joints proximal to the amputation. Relative motion will take place where the resistance

to torque is the least. During weight-bearing in the stance phase, this motion will tend to

occur between the stump and the socket, producing a most uncomfortable force on the

stump. This is particularly true of the above-the-knee suction-socket limb. In the below-

the-knee amputee, in addition to the major rotations that occur between the trunk and

the fixed foot position, there is further restriction of rotatory motion at the knee, produced

by the side hinge bars connecting the thigh lacer and the shank. In the case of below-the-

knee amputees who have adequate stump length and shape, the use of suction sockets and

an ankle mechanism may make it possible not only to provide for transverse rotation, but

also to do aw’ay w’ith side hinge bars and lacers, w-hich tend to restrict the normal action

of the knee.

The incorporation of a simple mechanism w’hich provides for transverse rotation of

sufficient magnitude, together with a unit for the return of the foot to the normal position,

may well constitute a major contribution to both the comfort of the amputee and the

improvement of function and synchrony in walking. An experimental mechanism has been

used on this project. All amputees who have employed this mechanism have attested to

the very marked improvement in comfort. Figure 8 shows reproductions of frames, taken

from high-speed motion pictures, of an amputee using the experimental rotatory mecha-

nism. The frames selected for reproduction show the six salient positions of the foot during

the stance phase. Attention should be called to changes in the gap (A) between the stops;

the width of the gap shows the amount of rotation occurring betw-een the leg and the foot.

The ultimate incorporation of this device, or modifications of it, in a prosthesis may well

become standard practice, and may be advantageous in leg braces.

CWdPLETE DISLOCATION oF THE TALUS

BY WENDELL J. NEWCOMB, M.D., PENSACOLA, FLORIDA, AND

ERNEST A. BRAY, M.D., LOUISVILLE, KENTUCKY

This case is reported because of its rarity and because it demonstrates the need for

immediate reduction, the possibility of revasculanization, and the policy of preserving

the talus.

A man, forty-five years old, jumped from a moving vehicle and struck the occipital port-ion of his skull

against the ground. He suffered a mild cerebral concussion and, therefore, had no recollection of the mecha-

nism of his associated ankle injury. He arrived at the hospital about one hour after the injury, and treatment

wa-s rendered immediately.

Physical examination showed inversion of the right foot- with a marked prominence anterior to the

lateral malleolus. The skin was very tense over the prominence. The roentgenograms revealed rotation of the

talus 90 degrees about the horizontal and vertical axes. The position of this bone was transverse to the hori--zontal axis of the foot, and its posterior portion was lateral and anterior to the fibula. No fracture was noted

<Figs. 1 and 2).

The treatment, carried out with the patient under spinal anaesthesia, consisted of traction by means of a

Kirschner wire through the calcaneus, and countertraction on a Steinmann pin in the proximal portion of

�the tibia. Considerable traction was necessary before pressure in a posteromedial direction, over the lateral

prominence, forced the displaced bone into the anteroposterior plane. Roentgenograms then revealed that

it had rotated 90 degrees about the vertical axis, while travelling the 90 degrees of displacement in the

horizontal plane.

The Kirschner wire and Steinmann pin were removed, and a toe-to-groin plaster was applied. This was

�immediately split anteriorly. After one week the plaster was changed; at this time a small necrotic area was


Transverse Rotation of the Segments of the Lower Extremity in Locomotion

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