Weak foot: Pathogenesis and treatment

WEAK FOOT: PATHOGENESIS AND TREATMENT JAMES GRAHAM, M.D.

Attending Surgeon, St. John’s and SpringfieId HospitaIs

SPRINGFIELD, ILLINOIS

S UCCESS in the treatment of the com-

mon type of weak foot due to poor posture depends upon the inteIIigent

emptoyment by the physician and the patient of five separate but simuItaneous Iines of attack: (I) maintenance of correct posture; (2) proper use of the foot in waIking; (2) exercises for the re-education of foot and Ieg muscles; (4) properIy constructed shoes that fit correctIy; and, (5) a temporary crutch in the form of an arch support.

In this discussion the writer has in mind the uncompIicated weak foot. Just as in the treatment of compIicated diabetes, there is a basic attack directed aIways toward the primary distortion of physioIogy. the derangement of carbohydrate metabo- Iism, and a secondary attack varying in nature with the complication, whether it be a dermatitis, an arteria1 degeneration or a neuritis; so too in the treatment of the compIicated weak foot there is a basic attack directed aIways toward the primary distortion of physioIogy, maIadaptation of the weight-bearing mechanism to the superstructure, and a secondary attack varying in nature with the compIication, whether it be ffat foot, smaI1 joint arthritis, caIIous, march foot, synovitis, periostitis, muscIe spasm, or any other of the pathoIogica1 sequeIs that have for too Iong been dignified as cIinica1 entities for the nourishment of an army of parasitic speciaIists.

No matter whether the cIinica1 condition present in a given case is simpIe weak foot or weak foot compIicated by ffat foot, etc., the basic attack is the same regardIess of variations that must be made in the secondary attack. The intent here is a presentation of the rationaIe in the attack on the primary distortion of physiology Ieading to the common type of weak foot, uncompIi- cated or compIicated. The discussion con-

terns the weak foot per se and not the compIications.

POSTURE IN RELATIONSHIP TO PEDAL

EFFICIENCY

The superstructure of the body is attached to and hangs from that portion of the spina coIumn situated above the IeveI of the fourth Iumbar vertebra, and it amounts to perhaps two-thirds of the entire body weight. This superstructure incIudes the cranium and its contents, the shouIder girdIe and the upper extremities, the thorax and its contents, and the organs contained in the abdominal cavity. The spina coIumn in turn rests on the sacral pIatform, that is, the top of the first sacra1 vertebra, and this pIatform is supported by the peIvic girdIe and the Iower extremities. In a one hundred and fifty pound indi- vidua1 the superstructure represents a Ioad of one hundred pounds on the sacra1 pIatform.

This Ioad on the sacrum is transmitted through the iIiac bones to the femora1 heads in a very definite manner (Fig. I). When the body is maintained in the erect position so that the fuI1 superstructure weight rests on the sacrum, there is compression in the acetabuIi about the areas of contact with the femurs, and there is tension at the symphysis. There is compression in the acetabuIi because the Ioad is resisted in the opposite direction by the femurs. Ten- sion at the symphysis is the resuIt of the tendency of the peIvic bones to flare as a force is appIied to the top of the sacrum. The anterior face of the sacrum is wider than the posterior face and the upper haIf of the sacrum is anterior to the Iower haIf, the top of the bone being rotated forward on an axis extending through the third sacra1 vertebra (Figs. 2 and 3). A force

486

applied to the top of the sacrum pushes the bone downward and forward, thus dragging on the posterior sacroihac Iigaments that are attached to the posterior iIiac spines (Fig. 2). This puII on the posterior Iiga- ments causes the iIiac bones to rotate about the sacrum as a f&rum so that the posterior spines approximate each other and the pubic bones separate.

The weight of the superstructure is in this fashion distributed through the peIvic arches to the heads of the femurs in the acetabuli, each femora1 head receiving 5” per cent of the weight. The Ioad is received on a femur eccentricaIIy and is distributed to the cyIindrica1 shaft through the trabecuIar arches in the neck of the bone (Fig. I). The femora1 bases, or con- dyles, rest directIy on the tibia1 pIatforms. The mechanica axis of each femur (Fig. 4) forms an angle of 87 degrees with the biIat- era1 horizonta1 axis of the knee j0ints.l The anatomical femora1 axis makes an angIe of 81 degrees. BeIow the knee joint the me- chanica1 axis of the femur forms a suppIe- mentary angle of 93 degrees with the horizonta1 knee joint axis. This axia1 devia- tion between femur and tibia represents the norma vaIgity of the knee joint and is the resuIt of the difference between peIvic width and the distance between the ankIe joints. Each tibia is mounted on a pedesta1, or foot.

Considered anatomicaIIy as a bony structure, the human pedesta1 is simiIar to an eccentric tripod, or, in other words, it represents a three Iegged stand of unequa1 sides. It is formed by a number of bones that as a unit contact the ground at three points, the base of the caIcaneus and the heads of the first and the fifth metatarsaIs (Fig. 5). The Ioad of the tibia1 coIumn supporting the superstructure is received on the astrag- aIus which is closer to the base of the calcaneus than to the heads of the metatarsaIs (Fig. 6). Because of the proximity of the astragalus to the caIcaneus, sIightIy over

1 STEINDLER, ARTHUR. Mechanics of Norma1 and Pathologica Locomotion in Man, SpringtieId, III., Chnrlcs C. Thomas, 1935.

three-fifths of the Ioad is dissipated fairly directIy to the ground posteriorly through the calcaneus whiIe the other two-fifths is

U L--J

FIG. I. Diagrammatic representation of weight transmission through the pelvic girdle.

spread anteriorIy to the metatarsa1 heads. Of course, as the Iine of gravity of the body is shifted forward in waIking, the metatar- sa1 heads receive more and more of the Ioad. When the Iine of gravity faIIs over the metatarsa1 heads, the entire Ioad is dissipated to the ground through them.

A static tripod, however, couId not serve as the human pedesta1 because the device used in supporting the body must be an adjustabIe one in order that it may accom- modate itseIf to the shifting center of gravity of a mobiie superstructure, and in order that it may serve as an organ of

488 American Journal of Surgery Graham-Weak Foot MARCH. 193,

locomotion. The foot, in addition to acting caI Iine running through the center of as a pedestal, whose function is the dis- gravity of the astragaIus faIIs to the inner sipation of Ioad to the ground, serves in side of a verticaI Iine running through the

L-CM

FIG. 2. F~ti. 3. FIG. 2. Diagrammatic representation of a cross section through the adult peIvis. (After Schroeder

in WiIIiams’ Obstetrics. New York, D. AppIeton-Century Co.) FIG. 3. Diagrammatic representation of a sagittal section through the adult peIvis Zustrating

pelvic in&nation.

each step as a spring or as the spring base of a faIIing body, its purpose being to break the impact of the superstructure of that faIIing body. Considered physioIogicaIIy, the foot represents a spring, consisting of a bony framework outIining the major stresses on arches that are maintained by muscIes and Iigaments in physioIogica1 tone (Fig. 7). It is a spring that prevents jarring to the superstructure.

Of the two functions, support of a mobiIe superstructure and Iocomotion, the Iatter is the more compIicated, and the features of the pedesta1 that make Iocomotion a more efficient function are those that de- tract from its efficiency in the function of support. The two mechanisms responsibIe for this spring action are: (I) the eccentri- caIIy Ioaded caIcaneus, and (2) the system of resiIient arches.

The astragaIus does not sit squareIy on the top of the caIcaneus but rides on a support, the sustentaculum, extending from the inner side of the bone (Fig. 8). A verti-

center of gravity of the caIcaneus. The caI- caneus is thus eccentricaIIy Ioaded.

For cIarity in study, the system of arches in the foot can be reduced to two main stress areas crossing each other. The first of these areas runs anteroposteriorIy and centers about the caIcaneus, the astragaIus, the scaphoid, the cuneiforms and the inner three metatarsaIs (Fig. 3). For convenience, this area is considered as an imaginary Iine in the form of an arch, and the Iine is caIIed the “IongitudinaI arch” (Fig. 7). The second area crosses the anterior Iimb of the IongitudinaI arch and transects the heads of the first and the fifth and the necks of the second, third and fourth metatarsaIs (Fig. 5). It is caIIed the “anterior arch.” The issue of the existence of the anterior arch has been confused2 by those who ap- parentIy have considered the arch as tran- secting the heads of the second, third and fourth metatarsaIs, rather than the necks

2 MORTON, DUDLEY J. StructuraI factors in static disorders of the foot. Am. Jour. Surg., g: 315, 19x0.

of these bones (Fig. 5). The anterior ex- between the forward extension ot’ that arch tremity of the Iongitudinal arch joins the and the anterior arch. crown of the anterior arch. Both arches The action of this mechanism in locomo-

FIG. 4. Orientation and axes of the knee joint; illustrating the ana- tomicaI and mechanical axes of the femur, the mechanical axis of the leg and the horizonta1 knee joint axis. (Steindier, Mechanics of Norma1 and Pathologica Loco- motion in Man. SpringfieId, III., Chas. C. Thomas.)

are rampant; that is, the crowns are not equidistant from the bases. The astragaIus forms the crown of the IongitudinaI arch, and the crown of the anterior arch is at the inner edge of the second metatarsa1. Load on the posterior extremity of the Iongitudi- nal arch is transmitted to the ground through the caIcaneus. Load on the anterior extremity of the IongitudinaI arch is divided

FIG. 5. The skeIeton of the foot drawn from the plantar surface. The curved line outIines the inner boundary of the supporting surface; the vertical line ilIustrates the transection of the necks of the middle metatarsats by the “anterior arch.”

tion is as follows: As the lower extremity is moved forward at the hip, the leg is extended at the knee. The center of gravity of the body is shifted anteriorly, causing

FIG. 6. The Sk&ton of the foot drawn from tllc mrdial aspect.

the body to faII forward. As the heeI of the extended Iower extremity makes contact with the ground, the weight of the superstructure is received on the head of the femur and is transmitted to the astragaIus (Fig. I). If the fuI1 Ioad of the superstructure were transmitted directly to the ground through the hee1 at this point, the superstructure wouId be jarred. Such, however, is not the case, for the astragaIus, resting eccentricaIIy on the caIcaneus, tends to faI1 (Fig. 9). A considerabIe part of the impact is broken by this faIIing of the astragaIus. As the center of gravity of the body moves stiI1 farther forward, the anterior supports of the tripod, the heads of the metatarsaIs, contact the ground. At this point there is a second impact. The body weight is shifted anteriorIS- on the IongitudinaI arch which now has a contact

490 American Journal of Surgery Graham-Weak Foot MAHCH, 1937

with the ground through the anterior arch. The faII of the astragaIus is sIowed con- siderably, but there is a continuance of its

FIG. ,A.

the arch wouId be subjected to consider- abIe strain, and the superstructure wouId be jarred. The bending, however, is brought to a gradual haIt by the give or bend in the anterior arch upon the crown of which the IongitudinaI arch rests (Fig. 7).

As was noted previousIy, the device that prevents jar to the superstructure, that is, the eccentricaIIy Ioaded caIcaneus, is the very device that Ieads to a breakdown of the pedesta1 in its function of weight bearing.

When the body maintains the erect position and is stationary, there is a tendency for the astragaIus to faI1, because of its eccentric position on the caIcaneus. Since the astragaIus forms the crown, or the peak, of the Iongitudinal arch, the superstructure, resting on the astragaIus, rests on the crown of the IongitudinaI arch, and the arch therefore tends to bend. If it bends too much, there wiI1 be strain on the Iigaments binding the bones together. This tendency toward bending wiI1 be resisted efliciently onIy when the crown of the arch and the supporting ends of the arch are in the same pIane just as a structura1 stee1 arch efi- cientIy resists the tendency toward bending produced by a Ioad on its crown only when the crown of the arch and the supporting ends are in the same pIane (Fig. 12). The astragalus is the crown of the arch; the base of the caIcaneus is the posterior support;

FIG. 7B. FIG. 7. The DedaI “arch” svstem. The two heavv wires crossing each other represent the imaninarv lines that

arch.” The finer wires’outline the inner &face of the are’ caIled &the “IongitudiiaI arch” and the “akerior supporting system. (Photographs of author’s model.)

faI1 in the bending of the IongitudinaI arch. If the anterior Iimb of the Iongitudinal arch rested on the ground, this bending of the arch wouId be brought to a sudden stop,

and the crown of the anterior arch is the anterior support. These three points wiII be in the same pIane onIy when the foot is inverted and adducted. When the foot is

in the \TaIgus, or abducted position, the anterior Iimb of the IongitudinaI arch, that is, the part from the astragaIus to the anterior arch, is not in the pIane of the posterior limb which is formed by the astragalus and the calcaneus.

The ke\- to an understanding of the mechanical distortion responsibIe for the weak foot lies in a proper appreciation of the support given to the anterior extremity of the IongitudinaI arch by the crown of the anterior arch. If the foot is to function effI- cientlv, the anterior support of the Iongi- tudina1 arch, the crown, and the posterior support, must be in the same pIane or, stated differentIy, the anterior and posterior Iimbs of the IongitudinaI arch must Iie in the same pIane: they must be co- planar. A consideration of the joints and the movements of the foot wiI1 show that such a mechanica arrangement is not possibIe when the foot is in the vaIgus position.

The two joints of the foot of fundamenta1 importance are the subastragaIoid joint with its two subdivisions, and the astragalo- scaphoid joint. The subastragaIoid joint between the astragaIus and the caIcaneus comprises two parts, an anteromedia1 part

ward beIow the head of the astragaIus (Fig. 9); (2) in movement about an anteroposterior axis the calcaneus tilts to one

FIG. 8. FIG. g. FIG. 8. Anterior view of the astragalus and

calcaneus in the normal reIationship. FIG. g. Showing the head of the astragalus

rotated inward and downward and the anterior face of the calcaneus rotated upward and outward.

side or the other (Fig. 9); (3) in movement about a IateraI horizontal axis there is vertica raising or Iowering of the head of the caIcaneus; (4) in anteroposterior movement there is advancement or retardment of the caIcaneus (Fig. I I ).

In the astragaIoscaphoid joint there is a considerabIe degree of motion, both gliding

FIG. IO.

j\ ,,’ ‘.___I

FIG. II. FIG. IO. The upper surface of the calcaneus. FIG. I I. Lateral view of astragab and calcaneus. The dotted line

represents the cakaneus in its advanced position.

and a posterior part (Fig. IO). WiIes3 has and rotary. This is made possibIe by the described cIearIy the subastragaIoid move- baII and socket construction of the joint ment by resoIving it into four parts: (I) in and by the encIosing capsuIe which is loose movement about a vertica1 axis the anterior aImost to the point of redundancy. end of the caIcaneus moves inward or out- The bones of the forefoot interlock in a

3 WILES, PHILIP. Flat feet. Lancel, 2: 1089, 1934. very compIicated fashion and they are,

492 American Journal of Surgery Graham-Weak Foot

with the exception of those in the big toe, Because of the cIose connection between bound together by interosseous Iigaments the forefoot and the calcaneus, the move- (Fig. 12). For this reason, onIy the slightest ments of the caIcaneus about the astragaIus

FIG. 12. In the upper diagram the astragalus is represented in exte;naI rotation. The center of gravity of the astragalus is in the pIane of the anterior and posterior supports of the longitudinal arch. Compare with Figure 7.

In the Iower diagram the astragaIus is represented in interna rotation. The center of gravity of the astragalus is not in the plane of the anterior and posterior supports of the Iongitudinal arch.

motion is possible in the tarsa or the tarsa metatarsa1 joints and, from a practica1 standpoint, the entire forefoot may be considered a mechanical unit working as one piece. The forefoot unit in addition is firmIy bound to the caIcaneus by the strong Iiga- ments and fascia1 bands on the pIantar surface of the foot, and motion in the joint between the forefoot and the calcaneus, the caIcaneocuboid joint, is practicaIIy negIigibIe. Since the forefoot is connected with the astragaIus by nothing more than the Ioose astragaIoscaphoid joint the whoIe underfoot, which is practicaIIy a unit composed of the forefoot and the caI- caneus, moves as one piece about the astragaIus.

are reflected in the forefoot. When the head of the caIcaneus moves outward and upward about the horizonta1 and vertica1 axes, the forefoot, moving with it, is abducted and pronated. When the head of the caIcaneus moves inward and downward, the forefoot is adducted and supinated.

With this summary of pedal movements in mind, the effects on the copIanar arrangement in the IongitudinaI arch of movements of the underfoot unit (caIcaneus-forefoot) about the astragaIus are now readiIy appreciated.

Outward and upward rotation of the head of the caIcaneus increases the eccentricity of the astragaIus on the caIcaneus (Fig. 9). This increase in eccentricity of

the astragalus moves the anterior extension of the plane passing through the centers of gravity of the astragalus and the calcaneus medialward (Fig. 12). The result is that the posterior extremity of the Iongi- tudinal arch moves out of the pIane of the anterior extremity. The crown of the arch obviously then is not in the pIane of the anterior and posterior supports, and the bending of the arch under load on the crown is not resisted efficiently.

A brief reconsideration of the transmission of superstructure load to the femoral heads will bring out how a shift in the center of gravity -of the superstructure produces a change in the reIation of the astragaIus to the caIcaneus and to the anterior arch, that is, a change in the reIation of the crown of the IongitudinaI arch to its posterior and anterior supports.

In the norma individua1 who maintains good posture, the peIvis is incIined to an angle of 30 degrees from the horizontal. The plane of peIvic inclination is taken as one passing across the top of the symphysis and through the third sacra1 vertebra (Fig. 3). The Iine of gravity of the superstructure falls through a pIane through the anterior halves of the sacroiIiac joints and through a plane through the posterior borders of the acetabuli (Fig. 13). The important peIvic girdIe platforms receiving Ioad, the sacra1 pIatform and the femora1 heads, are thus anterior to the Iine of gravity- of the superstructure. The tendency for the peIvis to tiIt backward is resisted by the iIiofemora1 Iigaments. Since the Iine of gravity of the superstructure falls behind the hip sockets, the shafts of the femurs, representing the supporting columns, wil1 be approximated to this Iine of gravitv onIy when they are behind the hip sockets. They wiI1 be in this position onl?. when the heads of the femurs are rotated externaIIy. For this reason slight external rotation of the femurs is con- sistent with good posture.

In the common type of postura1 defect due to poor postura1 habits, the head is dropped down and forward, the shouIders

are dropped, the thoracic kyphosis is increased, the abdominal muscles are relaxed, aIIowing the abdomina1 organs to fall down and forward, and the lumbar curvature is accentuated. The center of gravity of the body is shifted forward and the load on the sacrum is consequentIy moved forward. The sacrum as a resuIt rotates about its axis, the pelvis moving with it (Figs. 14 and IS). With this shifting forward of body weight, the Iine of gravity moves forward and fails in a pIane through the anterior borders of the hip sockets. The change thus produced in weight distribution of the superstructure necessitates an adjustment in the supporting femoral columns. They must be moved forward to positions anterior to the hip sockets. This is accomplished by interna rotation of the femurs.

Internal rotation of the thigh is refIected in the ankle. Rotation at the knee joint is possibIe onIy when the knee is flexed. It cannot be accomplished when the joint is fuIIy extended. The thigh and leg must therefore move as a unit when the knee joint is extended. At the ankIe the horizon- ta1 rotary movement is possible only when the foot is plantarfIexed completely. Ankle rotation cannot take pIace when the foot is perpendicular to the Ieg. It is obvious then that when the individua1 assumes the erect position, with the knee joint extended and with the foot heId at a right angIe to the leg, that the femur, the tibia with its attached fibula, and the astragalus must move as a unit.

The effect on the foot of interna rotation of the unit composed of the femur, tibia, and astragaIus, is the production of a rela- tive vaIgus position, because the astragalus, rotating internally, moves inward and downward in relation to the caIcaneus. The effect on the astragaIoforefoot relationship of this movement of the astragalus, about the calcaneus is the same as that of an outward and upward movement of the caIcaneus about the astragaIus because the calcaneus and forefoot move as a unit. It produces a valgus reIation between the forefoot and the astragaIus ( Fig. I 2 j.

494 American Journal of Surgery Graham-Weak Foot MARCH, 1937

VALGUS RELATION tion foIlows and the result is the valgus

The earIiest distortion in the foot then relation in the feet. is the vaIgus reIation between the astraga- The adducted pIantigrade position of the

FIG. 13. FIG. 14. FIG. 15.

FIG. 13. Mustrating how the Iine of gravity of the superstructure faIIs through the pIane of the posterior borders of the acetab&.

FIG. 14. Correct posture with the pelvis incIined to 30 degrees. FIG. I 5. Poor posture with peIvic inclination increased.

Ius and the underfoot, the underfoot being norma foot is maintained by severa groups taken as the caIcaneus-forefoot unit. Im- of posturing muscIes. When a normaI body proper posturing of superstructure mus- is at rest in the erect position, the various cuIature aIIows a sagging and shifting bones of the skeIeton, bound together by forward of the spina coIumn. Load on the Iigaments and the articuIar processes of sacra1 pIatform is thus distributed more the bones themseIves, are maintained in anteriorly, and the bone as a resuIt rotates positions of comfort and efficiency by pos- about an axis extending through the third turing muscIes. Maximum efficiency in the sacraI vertebra. The peIvis, being firmIy posturing of any group of bones forming attached to the sacrum, rotates with it so the skeIeton is the resuIt of perfect baIance that pelvic tiIt is increased. InternaI rota- between antagonistic and synergistic mus- tion of the femurs now brings these sup- cIe groups that are in a state of physioIogi- porting coIumns into the pIane of the ca1 tone. Maximum efficiency in weight anteriorIy shifted Iine of gravity of the bearing does not aIIow of the constant sub- superstructure. Internal astragaIar rota- jection to strain of any Iigaments and it

does not alIow of prolonged maintenance of contraction in any muscIe or muscIe group. Wiles has pointed out that the posture of the foot is dependent on the positions of its intrinsic joints. He has emphasized that body weight or superstructure Ioad is transmitted from one bone to the next in the peIvis, in the thigh, in the Ieg, and in the foot, and that the positions of the various joints in the foot are “aItered by active muscular contraction and maintained by the tone of the posturing muscIes.“”

The vaIgus reIation between the astraga- Ius and the underfoot, the result of fauIty posturing of superstructure muscuIature, disturbs the baIance in the foot posturing muscles and it is the strain of the extra Ioad thrown on one group of these muscIes that is behind the clinica manifestations of the condition known as weak foot.

An individua1 analysis of the major foot posturing muscIes foIIows.

The ,Vl. tibia&s anterior is a superficia1 muscle on the anterior surface of the Ieg arising from the IateraI condyIe and the IateraI surface of the tibia and from the crural interosseous membrane. The fibers converge downward to a ffat tendon that crosses the ankIe joint anteriorIy and drops over the inner side of the foot to be inserted into the media1 and undersurfaces of the base of the first metatarsa1 and the first cuneiform bone. The muscIe dorsiflexes the whoIe foot and eIevates the first metatarsa1 base and the first cuneiform.

The M. extensor hallucis longus arises from the anterior surface of the fibuIa and from the crura1 interosseous membrane, crosses the ankIe joint anteriorIy in a special compartment, and runs aIong the dor- saI surface of the great toe to gain its insertion in the base of the proxima1 phaIanx. It dorsiffexes the foot and the first toe.

The M. extensor digitorum longus arises from the IateraI condyIe of the tibia, the upper portion of the fibuIa and from the crura1 interosseous membrane. Its tendon terminates in four divisions that are in-

serted into the second and third phalanges of the four outer toes. The muscle dorsiflexes and pronates Reverts] the foot.

The M. peroneus tertius arising from the fibuIa and being inserted into the dorsal surface of the base of the fifth metatarsa1 is a part of the nl. extensor digitorum longus.

The A4. gastrocnemius, iv. soleus, and 1\/1. plantaris take origin from the posterior surfaces of the femur, tibia and fibuIa and unite to form a common tendon, the tendo- caIcaneus, that is inserted into the middIe part of the posterior surface of the caI- caneus. They ffex the Ieg and the foot, and supinate (invert) the foot.

The kl. jexor hallucis longus arises from the Iower two-thirds of the posterior surface of the fibuIa and from surrounding fascia. The fibers converge to a tendon that lies in a groove crossing the posterior surface of the Iower end of the tibia, the posterior surface of the astragaIus, and the undersurface of the sustentacuIum tali. The tendon passes forward to its insertion in the undersurface of the base of the first phaIanx of the great toe. Its action is pIantarfI exion, supination (inversion) of the foot, and pIantarffexion of the first toe.

The 111. flexor digitorum longus situated on the inner side of the Ieg arises from the posterior surface of the tibia. The fibers end in a tendon that passes behind the media1 maIIeoIus and into the plantar surface of the foot where it divides into fhur

sIips that are inserted into the termina1 phaIanges of the Iesser toes. The muscle pIantarff exes and supinates ( in\.erts ) the foot and flexes the Iesser toespIantarn_ard.

The M. tibialis posterior arises from the posterior surface of the tibia and fibula and the crura1 interosseous membrane. Its tendon runs in a groove on the back of the media1 maIIeoIus and to the pIantar surface of the foot where it is inserted into the scaphoid, the sustentacuIum taIi of the caIcaneus, the cuneiforms, the cuboid and the bases of the second, third and fourth metatarsals. This muscIe plantarfIezes and supinates (inverts) the foot.


The M. peroneus longus situated on the IateraI side of the Ieg arises from the IateraI surface of the fibula. Its tendon runs in a groove on the posterior surface of the externa maIIeoIus and bends under the cuboid bone in a groove to gain theunder- surface of the foot. After crossing the pIan- tar surface of the foot the tendon is inserted into the IateraI and undersurfaces of the inner cuneiform and the base of the first metatarsa1. The muscIe ff exes the foot pIan- tarward, pronates and abducts it. It puIIs the big toe to the ground.

The M. peroneus brevis arises from the lower two-thirds of the Iateral surface of the fibuIa beneath the peroneus Iongus. The fibers end in a tendon that runs in a groove on the posterior surface of the externa maIIeoIus to be inserted into the latera surface of the base of the fifth meta- tarsa1. Its action is pIantarflexion and pronation (eversion) of the foot.

The muscIes considered individuaIIy in the foregoing section may be grouped as foIIows :

Group I Muscles. M. tibiaIis anterior, M. peroneus tertius, M. extensor digitorum Iongus, and M. extensor haIIucis Iongus.

These muscles dorsiflex the foot at the ankIe joint. The M. tibialis anterior in addition eIevates the inner border of the foot (supination). The M. peroneus tertius in addition when working with the peroneus Iongus eIevates the outer border of the foot (pronation).

Group II Muscles. M. gastrocnemius, M. soIeus, and M. pIantaris.

These are powerful pIantarfIexors. They Iift the hee1 from the ground in Iocomotion.

Group III Muscles. M. tibiaIis posterior, M. flexor haIIucis Iongus, and M. flexor digitorum Iongus.

These muscIes are supinators and pIan- tarff exors.

Group IV Muscles. M. peroneus Iongus and M. peroneus brevis.

These two muscIes are pronators and pIantarff exors. The M. peroneus Iongus pulIs the big toe toward the ground.

The posturing actions of these muscIes when the body is erect are cIearIy iIIustrated by shifting the superstructure without changing the positions of the feet. In these functions the fixed point of a muscIe is its insertion in the foot, the action being a pull on the supporting tibia1 coIumn from the foot. When the body leans forward, the muscIes in Groups II, III and IV exert a backward puI1 on the tibiae. When the body leans backward, the Group I muscIes exert forward traction on the tibiae. It is quite apparent that the Groups II, III and IV muscIes together are much more power- fu1 than the Group I muscIes, for the body can Iean forward much farther than backward if the superstructure remains straight. If the body is supported on one foot and Ieans to the unsupported side, lateral traction is exerted on the supporting tibia by the M. peroneus Iongus. If the body now Ieans toward the supported side, media1 traction is exerted by the M. tibiaIis posterior.

WhiIe there are many minor foot movements, such as toe ffexion, adduction or abduction, and whiIe there are many in- termediate movements, such as the count- Iess combinations of pIantarff exion and supination or dorsiff exion and supination, there are onIy four major foot movements: (I) pIantarfIexion and (2) dorsiffexion through the ankIe joint and (3) supination or inversion and (4) pronation or eversion through the subastragaloid and astragaIo- scaphoid joints. Group I muscIes are the chief dorsiflexors and the muscIes in Groups II and III are the chief pIantarfIexors. The M. tibiaIis posterior is the major supinator whiIe the M. peroneus Iongus is the major pronator. IndividuaI muscIes take part in many different movements but each muscIe has onIy one of four major functions: dorsiff exion, pIantarA exion, supination or pronation.

Perfect foot posturing then is the result of muscuIar baIancing. The bones of the foot are moved by the antagonistic and synergistic contractions of these muscIes into positions that favor the transmission

YEI\ SI.RIES Vat.. XXXV, No. 3 Graham-Weak Foot Anlrricu1 Journ.~i ot St~rgrrv -197

of superstructure weight from bone to bone foot, that is, the crown of the longitudinal with maximum architectura1 efficiency and arch. bodiIy comfort. The bones are maintained It has been shown (vide supra) that, in-

I,

FIG. 16. Diagrammatic illustration of the hammock efiect of the tendons crossing the inner side of the foot: A, composite of B, the M. tibialis posterior, c, the M. flexor digitorum Iongus, and D, the M. flexor hallucis Iongus. (Whitman, Orthopaedic Surgery, Phila., Lea and Febiger.)

in these positions by the same muscIes in a state of physioIogica1 tone.

How, then, is the baIance in these foot posturing muscIes upset by the vaIgus reIa- tionship between the astragaIus and the underfoot (calcaneus-forefoot)? VaIgus relation (the reIative vaIgus position) Ieads directIy to a Ioss of tone in the foot supinat- ing muscles, those in Group III. Loss of tone in the Group III muscIes foIIows their assumption of the burden of supporting the astragaIus and the inner side of the

terna rotation of the astragaIus increases the eccentricity of that bone on the caI- caneus. With this increased eccentricity there is a consequent increased tendency toward faIIing of the astragaIus which means increased bending of the IongitudinaI arch because the crown of the arch, that is, the astragaIus, and its anterior and posterior supports are not in the same pIane.

In this reIative vaIgus position with the eccentricity of the astragaIus increased, the crown of the arch, being out of the piane


of its anterior and posterior supports, is architecturaIIy incapable of effIcientIy carrying Ioad. In the very beginning of the vaIgus reIationship part of the burden of holding together this architecturaIIy inefl?- cient structure is borne by the Iigaments. However, they do not stand the strain and the astragaIus turns farther inward and faIIs farther down.

The burden is then assumed by the Group III muscIes. Figure 16 iIIustrates how these muscIes form a hammock for the astragaIar head, the sustentacuIum (the astragaIar support) and the inner side of the foot. To carry this Ioad the Group III

muscIes must be in a state of active contraction. TonaI baIance between them and their antagnostic muscIes (Groups I and IV)

wiI1 no Ionger hoId the foot in position, the Group III muscIes being at an architectura1 disadvantage.

Thus in maintaining the foot in a position of rest in standing, the Group III

muscIes must remain in a state of activity or contraction. Such a situation is dis- tinctIy not physioIogica1.

This is the weak foot, the vaIgus reIa- tionship between the astragaIus and the underfoot. Poor superstructure posturing shifts the center of gravity of the body an- teriorIy. The shift forward is foIIowed by interna femora1 rotation. The astragaIus, moving with the femoraI-tibia1 unit, rotates internaIIy. The eccentricity of the astraga- Ius on the caIcaneus is increased by this movement of interna rotation and the as- tragaIus, forming the crown of the Iongi- tudina1 arch, is moved out of the pIane of its anterior and posterior supports, the calcaneus and the crown of the anterior arch. The crown of the arch faIIs (that is, the architecturaIIy ineflicient arch bends) under the Ioad of the superstructure. The burden of supporting the astragaIus is taken over in part by the hammock muscles in Group III. The active contraction thus made necessary in the Group III muscIes destroys the baIance of foot posturing.

VALGUS POSITION

The changes described constitute the physioIogica1 distortion Ieading to the weak foot, vaIgus reIation. VaIgus position (pronated foot) is the first major compIication of the weak foot and is followed in a vari- abIe period of time by flat foot, caIIous (corn), muscIe spasm, synovitis, periostitis, arthritis and rigid foot.

VaIgus reIation produces vaIgus position or pronation because of the tiIting of the caIcaneus. The increase in eccentricity of the astragaIus throws the superstructure weight farther mediaIward on the supporting sheIf of the caIcaneus, the sustentaculum. This tiIts the calcaneus; the outer border of its base is Iifted, the upper inner edge is puIIed mediaIIy, and the head rotates outward and upward (Fig. 9). In other words, the head of the calcaneus moves outward and upward through the vertica1 and horizonta1 axes. The forefoot, firmIy attached to the caIcaneus-forefoot unit, foIIows this movement of the caI- caneus; it is abducted or pronated. The weight bearing Iine in Iocomotion is then thrown out compIeteIy. Further discussion of compIications is purposeIy avoided.

DIAGNOSIS

The subject of diagnosis is passed with a warning note. PhysioIogicaI and anatomica diagnoses are as important in the simpIe and complicated weak foot as they are in heart disease or biIiary tract disease. Diag- nosis in heart disease differentiates causes, e.g., rheumatic and syphiIitic; determines anatomica changes, e.g., enlargement of the organ and the state of the vaIves; and it estimates physioIogica1 status, e.g., auric- uIar fibriIIation and decompensation. The proper evaluation of biIiary tract stagna- tion in any given patient must incIude a differentiation of causes, e.g., stone or dyskinesia of the choIedochoduodena1 bar- rier; it must take into consideration the anatomica changes in the tract, e.g., choIecystitis, choIangitis, liver cirrhosis; and it must inctude a physiologica esti-

\I \\ SFRII s \‘oI, X\(X\‘, No. 3 Graham--Weak Foot

mate based on various functional studies, such as the gall-bladder dye and galactose tests.

A diagnosis in peda1 Iocomotor abnor- malities must include cause, physioIogica1 distortion, anatomica change and the degree of impairment of function.

While the common and, in fact, the usua1 cause of weak feet is the anteriorIy shifted center of gravity of the body resuIting from poor postura1 habits (sIouch posture), it must be borne in mind that many other conditions such as anterior poIiomyeIitis, arthitic disturbances, injuries and struc- tura1 abnormaIities may underIie maIa- daptation of the weight bearing mechanism to the superstructure, and the possibility of the presence of these conditions must be eliminated before the peda1 disturbance is laid at the foot of poor posture.

An estimation of physioIogica1 distortion must take into account functiona kyphosis and Iordosis, pelvic tilt, femora1 and as- tragaIar rotation, caIcanea1 tilt, the degree of pronation, muscIe spasm, and, Iast and least, the degree of depression of the peda1 system of arches.

Anatomica changes incIude synovitis, arthritis, periostitis, skin changes, and the structural bone changes that occur in accordance with WOKS Iaw, “Every change in the form and function of the bones or of their function aIone is foIIowed by certain definite changes in their internal architecture, and equaIIy definite secondary aItera- tions of their external conformation, in accordance with mathematica1 Iaws.”

TREATMENT

In the foregoing paragraphs the pathogenesis of the weak foot has been presented. Assuming valgus reIation (weak foot) to be the physioIogica1 upset that leads to rigid foot, caIIous, etc., the primary treatment of these conditions must aim at the correction of vaIgus relation. Readaptation of the weight bearing mechanism to the superstructure must be the starting point in the treatment of the weak foot or any of its compIications, just as metaboIic read-

justment with diet is the starting point in the treatment of diabetes meIIitus and its complications, or as immunologic readjustment with diphtheria antitoxin is the starting point in the treatment of diphtheria and its complications. It is with this phase of treatment aIone, the basic attack upon which the treatment of any complication of the weak foot is buiIt, that the author is here concerned.

Treatment, if it is to be successful, must incIude five separate methods of approach to the pathoIogica1 physioIogy here presented and a11 five of these approaches must be made simuItaneousIy.

Any one of the five therapeutic factors under consideration : postura1 correction, correct usage of the feet, exercises, proper shoes and arch supports, wiI1 bring con- siderabIe relief to the patient suffering with weak feet, but no one of them empIoyed singIy wiI1 effect a cure and thereby give compIete relief. The great majority of foot sufferers have gone from one surgeon to the next, from the surgeon to the chi- ropodist, to the osteopath, the chiropractor, and the shoe saIesman, only to concIude that nobody had a cure for aching feet. Each of these individuaIs perhaps gave the patient some temporary comfort because he employed one or even two or three of of the five factors to be considered, but no one of them cured the patient because the five eIements of treatment were not em- pIoyed simuItaneousIy.

These five therapeutic factors, then, postura1 correction, correct usage of the feet, exercises, proper shoes and arch supports must be employed simultaneously.

MAINTENANCE OF CORRECT POSTURE

Correct body posture impIies that the bones of the skeIeton to which the soft tissues are attached are maintained in positions of maximum comfort subjectiveIy and maximum architectura1 efficiency (weight transmission) objectiveIy by a minimum of muscuIar effort.

Certain fairIy constant spinal curves center about the Iine of gravity of the body


in the normaI ad&. The convexities of the cervica1 and Iumbar curves and the con- cavities of the thoracic and sacra1 curves are forward. These curves do not exist in the newborn. It is not unti1 the infant begins to hoId its head erect in the fourth or fifth month that the forward curve of the cervical vertebras appears. After the seventh or eighth month, when the infant first sits aIone, the upper thoracic kyphosis is produced. Changes in the Iumbar spine begin with weight bearing in the second year and progress throughout chiIdhood. The body is heId in the erect standing position when the resistance of the iIiopsoas group of muscles is overcome by the erector spinae muscIes. PeIvic tiIt and the norma Iumbar curve are produced by the antagonistic actions of these two muscuIar groups.

The norma cervica1 curve is obIiterated when the head drops forward. When the head is heId correctIy, that is, up and back, a Iine between the inferior margin of the orbit and the externa1 auditory meatus, or roughIy, a Iine dividing the zygoma, is on the horizontar.

If the shouIders are aIIowed to faI1 forward, thoracic kyphosis is increased. It is onIy when the head and shouIders are heId up and back that the S-configuration of the cervica1 and thoracic vertebras wiI1 be normal. The norma relation of the thoracic vertebras, present when the shouIders are up and back, aIIows the chest to expand more freeIy. The cIose connection between adequate chest expansion and good thoracic and shouIder girdIe posture is demonstrated when one expands the chest in deep inspira- tion. In this movement the shouIders are thrown up, back, and out. When the head is erect and the shouIders are dropped, both the cervica1 and the thoracic curves are accentuated. When the head drops with the shouIders, the cervica1 curve is forward and the vertebras from the Iumbar region to the axis form one Iong curve.

The norma degree of forward curvature of the Iumbar spine is greatIy dependent upon the backward curve of the thoracic

vertebras. Thoracic kyphosis (increased curvature) diminishes thoracic capacity, the decrease in capacity being greatest in the upper thorax. Thoracic space is gained by a Iowering of the diaphragm. Lowering of the diaphragm together with wider dia- phragmatic excursion, which is the necessary consequence of kyphotic interference with rib motion, decreases abdominal capacity. The encroachment upon abdominal capacity is easiIy remedied because the abdomina1 muscIes bridging a shorter gap between the Iower ribs and the peIvis mereIy buIge forward. Lumbar Iordosis, then, is the resuIt of severa combining factors; shifting forward of the center of gravity of the body, encroachment upon abdomina1 capacity and the drag of the downwardIy and forwardIy displaced ab- domina1 organs.

The opposing curves of the Iumbar vertebras and the sacrum bear a definite reIa- tionship to each other. When the Iumbar curve becomes more acute (Iordosis), the superstructure Ioad carried by the Iumbar vertebras is shifted anteriorIy on the sacral pIatform and the sacrum, carrying with it the peIvis is tiIted.

Determination of the degree of peIvic incIination is perhaps the most important singIe factor in estimating the postura1 habits of an individua1. Many patients with maIadaptation of the supporting mechanism appear to maintain good posture and in them foot discomfort at first is appar- entIy not dependent upon poor bodiIy posture. These patients hoId their heads correctIy and keep their shouIders we11 back. Some of them even walk and stand with their feet pointing straight ahead. However, further examination usuaIIy re- veaIs increased pelvic incIination and Ium- bar Iordosis. These are the patients with poor posture who have heeded the constant admonitions of their friends and reIatives that they are getting “stooped over” and “round shouIdered.” They have raised their heads and shouIders and some of them have even “puIIed in their stomachs,” but they “haven’t puIIed in” their buttocks by rais-

Ntu S~nras Var. XXXV. No. 3 Graham-Weak Foot

ing their peIves. When the buttocks protrude, peIvic inclination is increased.

The femurs must be rotated externaIIy if they are to approximate the line of gravity of the body. ExternaI femora1 rotation is essentia1 to good posture. The feet must be supinated, that is, they must point straight ahead.

Since most of these patients are aduIts, it is best to spend some time in showing them what correct posture is. If the various eIements of good posture are cIearIy demonstrated, it is very easy for the patient to remember one or two simpIe exercises in connection with each phase of posture and to run through different ones during odd moments at work. The entire series of exercises shouId be performed at Ieast twice a day, night and morning.

If the patient can be made “posture conscious,” any form of Iight genera1 exercise wiI1 be a heIp in maintaining good posture. WaIking is avaiIabIe to anyone and is one of the best forms of genera1 exercise. How- ever, unIess a delinite amount of walking, two, three or six miIes, is prescribed for each daiIy stretch, the patient wiI1 not waIk.

In demonstrating good posture the patient is asked to stand with his back against a wall, with heels, the caIves of the legs, the buttocks, the shouIders and the head, touching the wal1. If the patient then pIaces his hand between the smaII of his back and the wall, he wil1 readiIy appreciate the Iarge space made by the abnormal Iumbar curvature. If he now pushes the smaI1 of his back against his hand, he can fee1 the pelvis rising. In this attitude he shouId waIk away from the waI1 and around the room. A return to the original position against the waI1 wiI1 revea1 whether or not the position has been altered in the waIk around the room. In running through the series of exercises this maneuver is repeated five times. Nothing serves better than this to impress pelvic inclination upon the patient’s mind. A simiIar exercise is that of lying face upward on the floor with the knees flexed so that the heeIs touch the buttocks. The object here is to push

the smal1 of the back into the floor. The patient alternately pushes the small of the back into the floor, and relaxes, twenty times.

For the cervica1 muscIes there is no better exercise than the circular or rotary stretch- ing of the tiIted head and neck with the muscIes on the upward side tense.

The shoulders may be stretched by the common arm extending exercise; ahead, to the side, and to the back. These movements are accompanied by deep breathing. A very Iight shoulder strap Iooping over both shoulders in front and fastening to a ring or buckIe between the scapuIas behind is aIways heIpfu1 and often it is necessary. In Iarge breasted, round shotrIdered girIs at puberty this strap is very important and shouId be used in conjunction with a Iight upIift brassiere that eIevates the breasts. The psychoIogica1 effect of rapid deveIop- ment of the breasts at puberty often leads to a dropping forward of the shouIders. The norma response is opposite to this.

Forward bending, with the knees extended, and leg raising, whiIe in the supine position, strengthen the abdominal muscles. Special attention shouId be given to this exercise because of the cIose connection between abdomina1 muscIe tone, pelvic in- cIination and Iumbar curvature.

In men, change from a belt to suspenders for supporting the trousers is of definite benefit. When the individual wears a tight beIt, there is a very marked tendency to Iet the abdomen rest on the beIt so that the abdomina1 muscIes consequently are not used for support. The beIt supporting the abdomina1 waI1 drags on the lumbar vertebras and thereby causes an increase in Iumbar curvature. The absence of any artificia1 abdomina1 support in those wearing suspenders necessitates the use of the abdomina1 musculature.

The effect of the femaIe girdle is per- nicious. The same girdIe that enhances the symmetry of the femaIe form in the robed state is the very factor that is responsibIe for the “pot belIy” of the disrobed form, a condition attaining such prevaIence in


younger women as to assume the propor- tions of a secondary sexua1 characteristic. Prominence of the Iower abdomen in the femaIe is normaI, but the “pot beIIy” is not.

PosturaI correction in the patient then depends firstIy, upon instiIIing into him an adequate conception of correct posture and secondIy, upon exercises that wiI1 increase the tone of posturing muscles. The exercises outlined in the foregoing paragraphs are Iisted with those for the feet to make one compIete set of exercises.

CORRECT USE OF FOOT

If body weight is to be carried effIcientIy on the IongitudinaI arch, the crown of the arch and its anterior and posterior supports must be in the same pIane. These conditions wiI1 be satisfied roughIy from the cIinica1 point of view when the inner edge of the second toe, the head of the astragaIus and the base of the caIcaneus are in the same Iine, with the foot adducted, that is, pointing straight ahead, and the astragaIus ex- ternally rotated. Voluntarily throwing the weight on the outer edge of the adducted foot causes externa1 rotation of the astrag- aIus. This can be demonstrated very simpIy by having the patient grasp his Ieg and rotate it outward; he feels the weight shift to the outer side of the foot and he sees the buIge beneath the inner side of his ankle disappear.

It is obvious that in addition to adduction and externa1 astragalar rotation, both supports of the anterior arch, nameIy, the first and fifth metatarsa1 heads, must be on the ground. Concentration of weight on the outer side of the foot pIaces the fifth metatarsa1 head on the ground. At the same time, however, this tends to Iift the first metatarsal. Wiles3 has described a most vaIuabIe exercise for teaching the patient to adduct the foot, externaIly rotate the astragaIus and push the first and fifth metatarsa1 heads into the ground, a11 at the same time. This exercise which is given beIow, I refer to as the “chair maneuver.”

The patient sits on a chair with the foot on the ground and with the Ieg below the knee vertica1. His Ieg is then heId just above the ankIe by the physician. This prevents leg movement. A mark is made on the floor about an inch and a haIf interna to the first metatarsal head and the patient moves the front part of the foot to the mark. It is important that onIy the front part of the foot be moved. The big toe is then depressed so that the skin beneath the metatarsa head touches the floor. The foot is then in its proper position. These movements of metatarsa1 depression and eleva- tion are repeated unti1 the patient is abIe to perform them without any leg motion. At first the metatarsal head is depressed onIy feebIy because of the difficulty in inhibiting the action of the M. tibiaI& anterior. In practice the patient should pIace two fingers on the outer side of the Iower third of the Ieg so that he can fee1 the peronea1 muscIes contract when he de- presses the first metatarsa1. After a IittIe time it is possibIe to raise and Iower the first toe in this position without moving the rest of the foot.

The same principIes can be brought out in another maneuver in which the patient waIks very sIowIy across the room steady- ing the IateraIIy extended arm against the waII. The beef is touched to the ground with the foot adducted and the body is moved forward with the weight on the outer side of the foot. With the weight stiI1 on the outer side of the foot the first metatarsal is depressed and the body rises on the toes with a spring. The waIking is con- tinued in this manner while the patient concentrates on “hee1, outer side of foot, big toe, and spring.” This maneuver im- presses upon the patient the Iever function of the foot.

It is at first diffIcuIt for the patient to maintain the correct posture of the feet con- stantIy for the reason that a conscious effort is required. However, unconscious postura1 contro1 must be preceded by a stage of posture consciousness. Exercises and postura1 aids, such as the “waI1 maneuver” and the

“chair maneuver,” heIp to make the indi- vidua1 posture conscious. When a patient begins to take notice of the very Iarge per- centage of peopIe waIking on the streets with their feet in the vaIgus position and with their buttocks sticking out behind, he is becoming posture conscious. He more frequentIy notices his own fauIty posture and corrects it. He soon learns to correct his own posture when he feeIs the tired and hea\->- sensation in his feet. Correction of posture with the onset of the heavy sensation in the feet soon becomes invoIuntary and practicaIIy reflex.

EXERCISES

Foot and Ieg exercises serve severa purposes: they strengthen the pIantar flexors and the adductors so that these muscIes can effIcientIy serve their Iever function in walking; they act in conjunction with the postura1 aids in creating invoIuntary con- trol of posture; and they stretch the pronators and dorsifl exors.

In waIking, the body is puIIed over the metatarsa1 heads by the pIantarfIexors, the metatarsa1 heads representing a fuIcrum and the pIantarfIexors the power. Since the first metatarsa1 bone is Ionger than the fifth, the metatarsa1 fuIcrum wiI1 be per- pendicuIar to the Iine of progression onIy when the foot is inverted, for inversion in effect pushes the fifth metatarsa1 forward. For this reason the body is raised correctIy on the metatarsa1 fuIcrum only when the supinators puI1 the forefoot inwardly at the termination of a step. The weight Iine shouId pass through the center of the knee and ankIe joints and extend across the inner edge of the second toe.

Raising the body on the toes strengthens the plantarffexors. In order that the supinators may be brought into action, tiptoeing shouId be accompanied by a roIIing out onto the outer sides of the feet. The foot exercises then shouId aim at rising on the toes and roIIing to the sides of the feet.

In a11 of these exercises the patient gets the fee1 of correct foot posture and at the

same time the pronators and dorsiflexors are stretched.

Patients find that they can run through many of the exercises Iisted beIow at odd intervaIs during the day, and this is ad- visabIe. However, the compIete set of exercises shouId be performed twice daiIy. It is often diffIcuIt at first for patients to go through some of these maneuvers bare- footed but they shouId strive to do this as quickIy as possibIe.

INSTRUCTIONS FOR PATIENTS

Standing: I. Head up, shouIders back, abdomen

in, peIvis up; 2. Feet four inches apart; 3. Toes pointing straight ahead; 4. Weight on outer edges of feet; 5. Arches cupped, Iike paIm of hand. Wulking: Take a two miIe stretch daiIy,

preferabIy at noon. This does not incIude waIking whiIe at work. Keep in mind:

I. Toes pointing straight ahead; 2. Weight on outer edges of feet; 3. Toes gripping the ground to cup the

arches; 4. Keep conscious of “heel,” “outside

of foot,” and “big toe and spring.” General: I. When standing, practice gripping

ground with toes; 2. When waIking, do the same; 3. When sitting, cross feet and practice

cupping arches. Exercises and Postural Aids: Twice daiIy,

barefoot as soon as possibIe, and toes aI- ways straight ahead. Time-six minutes.

I. WaII maneuver: begin at waI1, waIk around room five times, checking posture at waI1 each time.

2. Chair maneuver: depress and elevate the big toe twenty times (each foot).

3. Neck rotation with muscIes on stretch; five times.

4. Arms extended forward and backward with deep breathing, ten times.

3. Touch floor with knees straight; five times.

6. Leg raising, Iying on back; five times.

5% American Sournal of Surgery Graham-Weak Foot

7. Push back into floor and reIax aI- ternateIy; ten times.

8. Up on toes, cupping arches by throwing weight on smaIIer toes; ten times.

g. Up on toes; roI1 out on sides; and down; ten times.

IO. Feet together; roI1 out on ankIes; ten times.

I I. WaIk across room on toes, and back on outer sides of feet; three times.

12. ManipuIate feet as directed; five times.

PROPER SHOES

The primary purpose of the shoe shouId be protection of the foot. UnfortunateIy, however, civiIized man has turned this protective covering into a decoration and a support. The average shoe marketed today is designed to serve three purposes, (I) protection against the eIements and the hard surfaces of floors, sidewaIks and streets, (2) adornment in accord with the rapidIy changing styIes of saIes promotion mana- gers, and (3) support for a weakened organ that through improper use is unable to perform effIcientIy its primary functions of weight bearing and Iocomotion.

The foot, if properIy used, couId quite effIcientIy and comfortabIy carry on over the hard surfaces marking the pathways of civilization without the shock absorbing rubber heels and without the heavy soIes and shanks that characterize present day footwear. From the standpoint of peda1 efficiency, even in civiIized environment, the Iight weight Ieather mocassin of the Indian is not surpassed by the cumbersome Ieather shoe. The Indian moIded his mocassin to the shape of his foot; civiIized man moIds his foot to the shape of his shoe.

It is useIess in this day, however, to Iong for the mocassin of the past, since society couId hardIy be expected to adjust itseIf to the business man wearing mocassins in his off&e or to the Iady wearing them for the theatre. Even in the face of this the situation is not as sad as might be expected for there are many shoes on the market today that serve their protective and even their

decorative functions at a minimum of interference with weight bearing or Iocomo- tion. ProperIy designed shoes can be had in practicaIIy any store that carries even a fair range of shoe stock. These shoes, however, usuaIIy are not on dispIay and they must be requested spec&aIIy. Nor is the store manager to be blamed for this when the buyer is attracted to the store that most effectiveIy displays shoes conforming to the standards set by nationaIIy advertising fashion designers.

The fact that properIy designed shoes do not aIways measure up to our changing conceptions of attractiveness must be taken into consideration. LittIe diffIcuIty is experienced with maIe patients, since comfort usuaIIy commands deeper respect in the male foot sufferer’s mind than does styIe. Such is not the case with women. A woman couId hardIy wear a corrective shoe to a tea or a baI1, but, fortunateIy, such sIavery to foot heaIth is not necessary. Women wiI1 aImost aIways submit to the corrective shoe if they are toId that it must be worn onIy during the major portion of the day. The corrective shoe has its pIace in housework, shopping and waIking, and if it is worn during these times, the most preposterous of styIe shoes, so Iong as it is not frightfuIIy smaI1, can do no harm during an evening’s wear.

The inner border of the shoe aIong the first metatarsa1 shouId be straight and it shouId paraIIe1 a Iine perpendicular to the hee1 base. The misIeading Iines marked on the soIes of shoes by manufacturers shouId be disregarded since their purpose is iIIus- tration for high pressure saIes taIk rather than measurement for proper shoe design. The front of the shoe shouId have a wide outward and backward sweep from the tip of the first toe around and behind the fifth toe. The bIunt toe does not necessarily mark a properIy designed shoe and it often Ieads one into buying a shoe that is too narrow. Many good shoes, however, are made with bIunt toes for the reason that shoeman have diff&Ity in convincing the customer that a corrective shoe can have

a slanting toe. The blunt toe is easier to sell to the person hunting a comfortabIe shoe.

The “combination Iast” is perhaps best for the average foot and this is particularI; true in women. In the “combination Iast shoe, the baI1 is one or more sizes wider than the heel. There shouId be room enough in the baI1 and cap of the shoe to aIIow the toes to separate and straighten and to flex when standing and walking. At the same time, the counter shouId grasp the heel snugly and the vamp shouId puI1 up firmly over the instep.

In oIder peopIe a rigid shank is advisable. In children and young adults the shank should be flexible.

The soIe shouId be flat and fairly fI exibIe. The usua1 type of heavy rocker soIe makes perfect foot function an impossibiIity because the bulge downward of the soIe is just beneath the upward eIevation of the central metatarsa1 necks. It is necessary also for the sole to project beyond the border of the foot in weight bearing because if it does not, the dorsum of the foot is compressed by the vamp and the toe cap.

The hee1 of a shoe makes waIking easier by inclining the body somewhat forward. The reason for this is that the caIf muscIes cannot raise the body on the toes when the knees are extended, unIess the center of gravity is first shifted forward. The hee1 must be broad. Its height may vary from three-quarters of an inch in men’s shoes to one inch or one and one-quarter inches in women’s shoes. The increased eIevation of the Cuban heel is deceptive because the foot is lifted at a point farther forward. This hee1 was designed as one that wouId appear to be a Iow hee1 and at the same time appreciabIy eIevate the back of the foot.

The size of the shoe must be correct. If, under weight bearing, the vamp and the toe cap are stretched tightIy over the dorsum of the foot, the shoe is too narrow, and the reason for this is obvious. When the soIe is too narrow, the foot, when under pressure, buIges over the sides of the soIe

and puIIs down on the vamp. The best and simpIest test for Iength is the reIation of the first metatarsa1 head to the flare of the soIe. The metatarsa1 head must push downward at the inner flare of the sole. While checking on a patient’s shoe size, it is wise to make certain that the hose afford the feet adequate room.

It is always advisable to have the patient buy the shoes on approva1 so that they may be brought to the physician’s offrce for inspection. Too often the salesman wiI1 se11 a patient the wrong size or the wrong shoe because he does not have the particu- Iar shoe and size in stock at the time. In addition, the various appIiances and supports put in the shoe by the manufacturer for sales purposes can be removed at this time.

Since specia1 shoe adjustments are rareIy necessary in the treatment of the uncom- pIicated weak foot, discussion of this subject is omitted.

THE ARCH SUPPORT

The arch support is the factor of least importance in the treatment of the uncom- pIicated weak foot; in the compIicated weak foot it pIays a very important role. The support mechanicaIIy shifts the foot into its proper posture and it hoIds the foot in the corrected position unti1 proper exercises have eIevated the threshoId of fatigue in the pIantarfIexors and in the supinators.

Great caution must be exercised with the support. It is a temporary measure and it shouId be used only after the patient fuIIy appreciates that the arch support will not onIy not cure his condition but that it is the factor of Ieast importance in the treatment. Its value in aiding easily ex- hausted muscIes and in giving the patient the feel of correct foot posture is over- shadowed and invalidated when the patient thinks the support is the cure.

InteIIigent and cooperative patients whose work does not require prolonged standing, and whose muscIes are not too easiIy fatigued, progress more rapidIy without the support. When the support is not


used, the chair maneuver assumes stiII greater importance. The support must be used in those patients in whom the thresh- oId of muscuIar fatigue is Iow enough to Iead to daiIy discomfort, in those whose work requires standing for considerabIe periods of time, and in those who do not readiIy comprehend the chair and waI1 maneuvers.

When used, the support is worn continu- ousIy for from four to six weeks. At the end of this time its use shouId be tapered down over a period of two to four weeks so that within six to ten weeks from the time of beginning treatment, the patient shouId have discarded the support.

If the support is to assume, in part, the hammock function of the supinator muscIes and the caIcaneoscaphoid Iigament and if it is to hoId the foot in the corrected position, its shape must conform to that of the peda1 arch system and its size must conform to that of the individua1 patient. Few of the supports used meet either of these requirements.

The foot is a system of arches comprising an architectura1 unit (Fig. 7) and if the Ioad carried by the unit is improperIy distributed at any point, the entire system is subject to improper stresses. The so-caIIed inner and outer IongitudinaI arches, the anterior and the transverse arches are mereIy imaginary Iines representing major stress areas in an architectura1 system. For this reason, the practice of supporting one of these imaginary arches, or stress areas, in the hope of correcting the improper sub- jection to stress throughout the entire foot, is obviousIy iIIogica1. If one area is subjected to improper stress, Ioad distribution in the entire system must be abnorma1.

The practice of using factory made supports, or standard, ready-made forms, is Iikewise a mistake. The variations in the size and shape of the peda1 arch system cannot be met by ready-made supports. Feet may be Iong and narrow or they may be short and broad; the dome of the arch system may be high or Iow or it may be acute or obtuse; the toes may be long, or

they may be short and thick. The support must be made to fit the individua1 foot.

The shape of the eIevated supporting surface shouId simuIate that of the mode1 shown in Figure 7, if it is to support the entire unit. The eIevation begins just behind the head of the first metatarsa1 (Figs. 5 and 17) and runs outward and forward in a curve around the head of this bone to gain the undersurfaces of the necks of the second, third and fourth metatarsaIs. It then makes a Iong sweep backward running media1 to the fifth metatarsa1 head but slipping graduaIIy, in its backward sweep, beneath the media1 half of the fifth metatarsa body and the cuboid bone. Just posterior to the caIcaneocuboid articuIation it makes a fairIy sharp media1 turn to end at the media1 side of the foot in front of the tuberosity of the caIcaneus.

CIinicaIIy, the guiding points in mapping a support for the foot are the first metatarsa head, the necks of the second, third and fourth metatarsaIs, the fifth metatarsa1 head, the caIcaneocuboid articuIation and the anterior and media1 border of the tuberosity of the caIcaneus. The patient stands on a piece of paper, with his foot pointing straight ahead, and a Iine is drawn around the foot (Fig. 17). Marks are then made just posterior to the heads of the first and fifth metatarsaIs, A and B, at the caIcaneo- cuboid articuIation, c, and just anterior to the tuberosity of the caIcaneus, D. The patient then sits down whiIe keeping his foot in pIace on the paper. The front of the foot is Iifted so that the site of the third metatarsa neck may be determined by paIpa- tion. A mark is pIaced at this point, E.

These marks are then connected by a Iine. In making the support, a piece of heavy

paper is cut to fit the insoIe of the shoe (Fig. 18). The tracing of the foot, on which the figure of the eIevated area has been drawn, is then transposed to the paper representing the shoe insoIe. Two pieces of thin Ieather, tripIe spIit pigskin or caIfskin, are next cut from the insoIe pattern. The Ieather piece that wiI1 be the top is marked from the insoIe pattern and a smal1 flap is

\I \\ ‘;tHIES var.. xxx\-, No. 3 Graham-Weak Foot .4,nCl_ic:,n .lvurn:,l 01 5II Cli<‘i” ;o:

allowed to protrude from the inner edge SUMMARY

of what wiII be the supporting surface The author has attempted a presentation i,Fig. 19). The two leather pieces are now of the rationale in the attack on the distor-

FIG. 17. FIG. 18. FIG. 17. The tracing of the patient’s foot. FIG. 18. The tracing of the shoe insoIe. FIG. 19. The tracing of the upper surface of the support.

FIG. 19.

sewn together around the edges and aIong the Iine marking the eIevating surface so that a pocket, representing the supporting surface, opens on the inner side beneath the Aap.

A piece of harness feIt is cut to the shape of the supporting surface, its edges are beveIed to the shape of the foot, and it is slipped into the Ieather pocket. The height of the harness feIt and its degree of eIeva- tion vary with the individua1 foot.

There are, of course, many variations from this support but this is the one that is usuaIIy indicated. Such a support con- forms in shape to the patient’s arch system, it fits the shoe, and fits the foot. It is easily made in a short time with the heIp of a competent shoemaker.

tion of physioIogy Ieading to the common type of weak foot, that associated with poor body posture. The discussion has been Iimited to the uncompIicated weak foot, vaIgus reIation, this abnormaIity being

taken as the starting point in a Iarge number of the pathoIogica1 conditions of the foot, such as flat foot, caIIous, arthritis with true or faIse ankyIosis, etc., that resuit from maIadaptation of the weight bearing mechanism to the superstructure.

Briefly, the sequence of events appears to be as foIIows: sIouch posture with a forward shift of the Iine of gravity of the botiy, Iumbar Iordosis, increased peIvic tiIt, interna femora1 rotation, interna astragaIar rotation, vaIgus reIation. The effect of vaI-

508 American Journal of Surgery Graham-Weak Foot MARCH, 193,

gus reIation on the eficiency of the foot is It is obvious that the foot cannot func- discussed. tion effIcientIy when the shoe covering it

It is pointed out that there are five is not properIy constructed and correctIy therapeutic factors concerned in readapting sized. The elements of a good shoe are the weight bearing mechanism to the super- discussed. structure and that al1 of these factors-pos- The arch support is considered from the tura1 correction, correct usage of the mechanica and cIinica1 points of view. feet, exercises, proper shoes and arch sup- Patients for postura1 correction must be ports-must be employed simultaneously. seIected with care since readjustment of a

Absolute cooperation of the patient is posture that has been maintained for years essential since the pIan of treatment has as is a serious matter. In patients over fifty its goal the deveIopment in the individua1 years of age the weak foot is aImost invari- of a consciousness of posture that is foI- abIy accompanied by various pathoIogica1 Iowed eventuaIIy by a posture reflex. This sequeIs. PaIIiative treatment of these com- necessitates first of a11 the instruction of pIications shouId be undertaken immedi- the patient in the eIements of correct pos- ateIy and foIIowed whiIe postura1 correction ture. The “waI1 and chair maneuvers” are is in progress. This Iatter correction must described in this connection. be sIow and extended over a period of many

DeveIopment of negIected muscIes months or even several years. through exercises enabIes the patient to puI1 himseIf into correct posture and to stay

The author wishes to express his appreciation for the vaIuabIe assistance and criticism

there. This act in time becomes reffex. An of Mr. W. Gordon Garretson, Division of exercise routine is given and expIained. Architecture and Engineering, State of Illinois.

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Weak foot: Pathogenesis and treatment