Evaluation and Selection of Shoe Wearand Orthoses for the Runner

Michael H. Yamashita, PTEastside Sports Rehab, P.O. Box 6908, Bellevue, WA 98008-0908, USA

Every athlete seeks out equipment to maximize his/her sport performanceand minimize risk of injury. The two primary equipment variables in therunners tool box are running shoes and orthoses. Runners repeatedlysubject their bodies to stresses that are equal to two to three times their bodyweight [1,2] for a huge number of cycles each time that they participate intheir sport. Few runners are structurally ideal; this results in a range ofcompensations that contribute to ineciencies and, potentially, injury. Thepurpose of this article is to educate clinicians regarding the basic evaluationof the patient to assess appropriate shoe wear and to recognize when over-the-counter or custom orthosis intervention is necessary. To do thiseectively, a basic understanding of foot and ankle mechanics is essential.

The importance of the subtalar joint/midtarsal joint relationship

The subtalar joint (STJ) consists of the talus superiorly and the calcaneusinferiorly (Figs. 13). With an average axis orientation of 42 to thetransverse plane and 23 to the sagittal plane, the primary componentmotions are eversion/abduction and inversion/adduction, with inversion/eversion occurring in a 1:1 ratio with adduction/abduction based on theaverage axis orientation [35]. The primary importance of the STJ is that itsposition inuences midtarsal joint (MTJ) motion. The MTJ consists of thetalonavicular articulation and the calcaneocuboid articulation (see Figs 2and 3). The talonavicular joint has primary component motions of eversionand inversion (thus, the longitudinal axis), whereas the calcaneocuboid joint

Phys Med Rehabil Clin N Am

16 (2005) 801829has primary component motions of dorsiexion/abduction and plantar-exion/adduction (thus, the oblique axis). Note that signicant mobility inall three planes is available in the MTJ. This allows the MTJ to compensate

E-mail address: michaelyamashita@eastsidesportsrehab.com

1047-9651/05/$ - see front matter 2005 Elsevier Inc. All rights reserved.doi:10.1016/j.pmr.2005.02.006 pmr.theclinics.com

for restrictions or hypermobility in adjacent joints, which often leads toinjury.

Arguably, it is the goal of the running shoe or orthosis to control thetiming, rate, and excursion of STJ motion to allow the joints and muscles inthe lower extremity to function in a range that is closer to that required foroptimal shock absorption and force transmission. STJ position determinesMTJ function because when the STJ is everted during lower extremitypronation, the MTJ axes become more parallel, and subsequently loosen

Fig. 1. (A) Anterior view of subtalar joint. (B) Posterior view of subtalar joint.

802 YAMASHITAthe MTJ to provide shock absorption and to allow accommodation tovariations in the running surface [6]. This should occur simultaneouslythrough the foot, and distal to proximal in the lower limb from heelstrike

through midstance after which the lower extremity should begin toresupinate from proximal to distal [1]. As the STJ inverts from midstancethrough the propulsive phase, the MTJ axes become more perpendicular;this restricts MTJ motion and provides the lower extremity musculaturewith a sti forefoot [6] with which to propel forward.

When structural deviation, muscle restriction, or weakness interrupts thenormal timing, excursion, or rate of this sequence, running pathomechanicsoccur which negatively impact eciency and performance, and ultimatelycan result in acute or chronic injury.

Normal pronation

Pronation is a much maligned motion in the runners vocabulary. It is,however, an essential part of the running cycle because it allows for shockabsorption and accommodation for terrain when it occurs during the correct

Fig. 2. Talonavicular joint. (A) Talus. (B) Navicular. (C) Talonavicular joint. (D) Calcaneus.

803SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 3. Calcaneocuboid joint. (A) Calcaneus. (B) Cuboid. (C) Calcaneocuboid. (D) Talus.

phase of gait, at an appropriate rate, to the appropriate extent, andtransitions to resupination at the appropriate time. Closed chain pronationof the STJ is associated distally with talar adduction and plantarexion aswell as eversion of the calcaneus which unlocks the MTJ and facilitatesaccommodation of the foot to the ground. Concurrent with STJ eversion,tibial internal rotation also occurs [3], which unlocks the knee and allows thequadriceps to absorb shock. As motion moves more proximal, knee exionand valgus occur along with hip internal rotation and adduction.

Normal supination

Closed chain supination of the STJ locks the MTJ to provide a rigid leverfor propulsion. Lower extremity motion, associated with closed chainsupination, includes hip external rotation and abduction, knee extensionand varus, tibial external rotation, talar abduction and dorsiexion, andcalcaneal inversion. Supination also must occur at the correct phase of gait,at the correct rate, to the appropriate extent, and with transition topronation at the appropriate time for ecient function to occur.

Running versus walking

There are several obvious dierences between running and walking thatmust be considered when making decisions about appropriate shoe wearand orthoses. The vertical ground reaction force increases to approximatelythree times body weight in the runner; it increases even more when runninghills. There is a narrowing of the base of gait with running [7], which acts asfunctional tibial varum and requires increased STJ compensation. Rate andrange of motion in all planes increases; however, motion in the transverseplane increases at a greater rate than motion in other planes with an obviousdominance of trunk counterrotation at greater speeds. This necessitatesadequate range of motion to avoid pathologic compensations, particularlywith respect to talocrural joint (TCJ) dorsiexion, hip extension and hipinternal rotation, and STJ eversion. Additionally, because of the increasedrate of motion, greater eccentric control is required by the entire system.Keeping this in mind, if the STJ axis is closer to the frontal plane (high axis),as in a higher arched foot, the proportion of tibial rotation that is associatedwith each degree of STJ inversion/eversion becomes higher [4]. Therefore,greater eort is required to control proximal transverse plane motions thatare associated with pronation.

Other dierences to observe between running and walking are the

804 YAMASHITAdecrease in vertical excursion of the head, decrease in duration of gait cycle,decrease in the ratio between time spent in stance phase versus swing phase[8], and the shift to a oat phase versus double limb support. Withincreasing speed, location of initial contact generally shifts forward to the

midfoot, or the forefoot in faster runners, which provides an argument forpurposefully evaluating what features in the midfoot and forefoot of therunning shoe and orthosis would be appropriate.

Shoe anatomy

Every shoe manufacturer has its proprietary technology for cushion andmotion control, but the goal and eect of each brands combination ofcomponents is similar. The pertinent anatomy of the running shoe includesthe last (refers to the shape of the shoe), which can be curved, semicurved, orstraight (Fig. 4); the midsole, which can be dual density and composed ofa variety of materials with varying stiness (Fig. 5); the outsole, which,again, can be composed of a variety of materials with dierent durabilityand characteristics; the heel counter (Fig. 6), which can vary in stiness andcontributes to rearfoot control; and the upper, which can have a variety ofmaterials that can be oriented in a manner to resist the stresses that areassociated with normal or abnormal gait mechanics. The two methods bywhich the upper is joined to the midsole also are important. The rst is sliplasting, which refers to a shoe that has a midsole that is stitched to the upperand allows the sti foot to move more freely. The second is the board lastedshoe, which uses a rm brous board between the midsole and the upperand provides a more stable base for function of the exible foot. Therunning shoe also can use a combination of board and slip lasting, which isreferred to appropriately as a combination last.

805SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 4. Cushion shoe with curved last (Asics; A). Stability shoe with semicurved last (Brooks;

B). Motion control shoe with straight last (Brooks; C).

Shoe types

The runner, essentially, has three broad categories of shoes from which topick. These categories are cushion shoes, stability shoes, and motion controlshoes. Features may overlap and shoe t may vary from brand to brand, butthis provides the individual runner with an excellent opportunity to nd justthe right shoe features and t.

Cushion shoes

Generally, cushion shoes are best for the patient who has an exces-sively supinatory gait to provide additional shock absorption, although

Fig. 5. Medial view of motion control shoe with dual density midsole (Brooks). (A) dual density

midsole; (B) heel counter; (C) upper.

806 YAMASHITAFig. 6. Posterior view of motion control shoe heel counter (Brooks). (A) heel counter; (B) dual

density midsole.

biomechanically ecient runners also can benet from the cushioning that isaorded by this type of shoe. Typically, the shoe is built on a curved- orsemicurved-shaped last and will be slip lasted or combination lasted (board-lasted rearfoot, slip-lasted forefoot) with cushioning in the midfoot andforefoot. The midsole may be broader through the forefoot and rearfoot,but narrower through the midfoot, and appears somewhat hourglass-shaped(Fig. 7A). With the absence of a dual-density midsole and with minimaladditional reinforcing materials overlying the narrower midfoot region, thecushion shoe allows more pronation to occur to facilitate shock absorption.This is an obvious contrast to a motion control shoe, which is left broaderthrough the same area to facilitate greater torsional stability (Fig. 7B). Thisdierence becomes obvious when performing long axis and sagittal planestability tests on the cushion shoe (Fig. 8).

One other important consideration with regard to cushion shoes isspecic t. The supinator tends to have a C-shaped foot with a high arch,a wide forefoot, and, often, a clawing of the toes which necessitates a highand wide toe box.

Stability shoes

Stability shoes are best for the mild to moderate overpronator. Typically,they are semicurved or straight lasted and usually are combination lasted.

807SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 7. (A) Bottom of cushion shoe with tapered midfoot shape (Saucony). (B) Bottom of

motion control shoe with broad midfoot (Brooks).

These shoes usually provide a compromise between motion control andcushioning by using materials that assist in shock attenuation, but alsoincorporate some motion control feature, such as a rm heel counter; dual-density midsole; and, often, a more rigid material imbedded into the midfootregion of the midsole to facilitate greater torsional rigidity. The densermaterial in a dual-density midsole typically is a dierent color than the restof the midsole and is present from the medial side of the rearfoot to theregion just distal to the talonavicular joint, or as far forward as the regionproximal to the metatarsal heads (see Fig. 5).

Motion control shoes

Motion control shoes are best for the moderate to severe overpronator.They incorporate all of the motion control features of the stability shoe, butalso may include a reinforced heel counter; extension of the denser midsolematerial proximal to the metatarsal heads for greater control during thepropulsive phase of gait; and a straight, board-lasted construction. Whenassessing the motion control shoe, the medial side of the rearfoot should benoncompressible by hand, it should not be possible to deform the shoe alongthe longitudinal axis when grasping the front of the shoe with one hand andthe back of the shoe with the other, and the shoe should ex in the sagittalplane through the metatarsal phalangeal region, but not the midfoot(Fig. 9). Additionally, shoes should be observed from behind to conrm that

Fig. 8. (A) Example of deformation along the longitudinal axis allowed by cushion shoe

(Brooks). (B) Example of sagittal plane midfoot motion allowed by the cushion shoe (Brooks).

808 YAMASHITAthe heels are vertical and that symmetry is present from side to side. Thisevaluation is as important in assessing an old shoe for replacement, as it isfor assessing the new shoe for purchase, especially considering that it should

Fig. 9. (A) Example of medial rearfoot noncompressibility in the motion control shoe (Brooks).

809SHOE WEAR AND ORTHOSES FOR RUNNERS(B) Example of longitudinal axis stability associated with the motion control shoe (Brooks). (C)

Example of sagittal plane motion occurring at the metatarsal phalangeal joints versus the

midfoot in the motion control shoe (Brooks).

serve as a neutral and stable base for function of the runner who uses footorthoses to facilitate normalization of gait mechanics.

Anatomy of the orthosis

The biomechanical orthotic device essentially is made up of a shell,rearfoot posting, and forefoot posting (Fig. 10). Other features are used forspecic issues, but these are the three essential components.

The shell is molded from a representation of the foot with the STJ ina neutral position (see section on casting technique below). The arch heightof the shell can inuence the rate of pronation and can provide pro-prioceptive feedback. In addition, the depth of the heel seat, or, conversely,the height of the shell that cups around the heel, also inuences rearfootcontrol. The shell thickness and rigidity also can inuence control orcushioning.

Rearfoot posting is a wedge that is applied to the proximal/plantar aspectof the shell to gain early control of motion or to provide cushioning at heelstrike and through early stance. The goal is to inuence STJ motion andposition, which will inuence MTJ function during the transition tomidstance and propulsion. The absence of rearfoot posting, even ona neutral device, compromises rearfoot stability by allowing rocking of theshell within the shoe as a result of the rounded contour of the rearfootportion of the shell (Fig. 11).

Forefoot posting is a wedge that is applied to the distal/plantar aspect ofthe shell to inuence deviation from neutral alignment of the bonystructures in the lower extremity. By addressing lower extremity positionaldeformity with a forefoot wedge, abnormal STJ compensation is prevented;this decreases compensatory pathomechanics distally and proximally. Themost obvious example of this is the forefoot which is in varus when the STJis in a neutral position. This scenario presents a situation in which theforefoot is o the ground when the STJ is in neutral and the condyles of thecalcaneus are on the ground (Fig. 12A). As the foot shifts into midstance

810 YAMASHITAFig. 10. Side view of orthotic. (A) shell; (B) rearfoot post; (C) forefoot post to sulcus; (D) heel

seat.

and propulsion, the STJ must evert to allow the forefoot to contact theground (Fig. 12B). This unlocks the MTJ just as it should be locking toprovide a rigid lever for propulsion. This results in prolonged pronationwhich forces the rst ray (rst cuneiform and rst metatarsal) into

Fig. 11. Posterior view of orthotic without rearfoot posting.

811SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 12. Neutral STJ cast representation of forefoot varus deformity. (A) Neutral STJ position

cast reveals forefoot varus relative to a vertical rearfoot. (B) Neutral casts of a patient who has

forefoot varus deformity that represents STJ eversion compensation at midstance.

a dorsiexed position and excessively loads the second metatarsal. In thissituation, the forefoot post builds the ground up to the forefoot, therebypreventing the need for compensatory STJ eversion at midstance andfacilitating a stable MTJ and rst ray during the propulsive phase of gait.

Types of devices

There are two types of orthotic devices. First, there is the neutral over-the-counter device which aords a nonspecic arch contour that may assistin some motion control, proprioceptive feedback, and cushioning, but failsto address positional/structural deformity and the obligatory compensationsthat result. In an excessively pronatory gait, the arch simply acts asa buttress to slow the compensatory pronation. In contrast, biomechanicalorthotic devices address the source of the compensation and slow the rateand extent, and alter the timing of the compensation using rearfoot andforefoot posting to build the ground up to the foot. In addition, the shellacts as a support for compensatory midfoot motion. In this way, the archcontour of the custom device must only act as a secondary support, ratherthan a primary one, because the posting facilitates more appropriate STJand MTJ function. This results in less compensatory inferior and medialnavicular excursion (navicular drop) as well as a stable rst ray in the case ofearly, excessive, and prolonged pronation.

Custom devices for the runner can be classied by stiness. There are rigid,semirigid, and exible devices. The easiest way to think about appropriaterigidity is that the rigid foot requires a more exible device and amore exiblefoot requires a more rigid device; the goal is to provide adequate stability tothe exible foot and adequate cushioning to the sti foot.

Importance of appropriate casting technique

Because shell contour signicantly aects midfoot control, it is importantto evaluate an often overlooked aspect of orthosis fabricationthe castingtechnique that is used by the dispensing provider. This plays a pivotal role inthe ultimate comfort and function of the custom device.

A variety of techniques are used to capture the contour of the foot tofabricate custom orthotic devices. The two broad categories are weightbearing (eg, stepping into a box with compressible foam) and nonweightbearing (eg, using plaster splints to create a slipper cast of the foot). In each,the key is to capture the contour of the foot with the STJ in a neutralposition. This assures that the contour of the device at midstance matches

812 YAMASHITAthe arch contour of the patient. Obviously, the weight-bearing arch contourthat is dictated by the nished device depends on the posting angles that arespecied by the practitioner; they need to support a neutral STJ position atmidstance to normalize gait mechanics.

Posting anglesthe angles of the wedges that are applied to the rear andforefoot of the devicesare the predominant inuences on STJ position inweight bearing; however, positioning the STJ in neutral while capturing thecontour of the foot for orthosis fabrication is essential for comfort. If thefoot is pronated, the resultant device has a lower than ideal arch contour,whereas if the foot is supinated, the arch height is higher. Less support isprovided during the stance phase with the lower arch contour, and increasedcompression and discomfort result from a device with an excessivelyelevated arch contour. Capturing the pathologically compensated positionof the foot in midstance, whether that tendency is toward pronation orsupination, has the unfortunate consequence of a device contour thatreects and facilitates the compensated position in midstance. These errorsare possible with weight-bearing and nonweight-bearing techniques, so theimportance of conscientious maintenance of STJ neutral position whencasting cannot be overstressed.

For this reason, it is the authors bias to use nonweight-bearing castsbecause it is simple to maintain STJ neutral position by palpating the headof the talus for equal medial and lateral prominence with the thumb andforenger of one hand while applying a mild dorsiexion force over thefourth and fth metatarsal heads to facilitate neutral talocrural jointdorsiexion (Fig. 13). This simulates the foot and ankle orientation inmidstance with the STJ in a neutral position [9]. In contrast, it is dicult tocontrol the forefoot with a weight-bearing casting technique, such as a foambox into which the patient steps. In this situation, the forefoot may tend tomove in the direction that it moves commonly (ie, it tends to move into itstypical position of compensation). This results in an inaccurate represen-tation of the foot at midstance with the STJ in a neutral position andreduces the comfort and eectiveness of the device.

813SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 13. Neutral STJ casting technique.

The subjective evaluation

As with all patients, the subjective evaluation of the runner givessignicant clues as to what the objective evaluation will reveal. The questionof current symptoms and previous injuries gives a broader picture of thepatients history of tolerance for running as well as possible biomechanicalcontributing factors. Chronic symptoms, insidious onset of symptoms, andfamily history may point out the likelihood that structural issues contributeto running pathomechanics. In contrast, traumatic onset or rst time injurymay indicate injury in the presence or absence of additional biomechanicalfactors. Recent initiation of a running program, overtraining, road camberand surface type also can contribute to injury without a bias towardpathomechanics as a primary contributing factor.

All runners training schedules should be scrutinized for appropriatemileage progression and appropriate rest. Intensity parameters consist ofdistance, speed, hills, terrain, and duration. Speed of the individual runneralso should be considered because of the dierent predominant inuencesthat are associated with running gait versus jogging or walking.

Additionally, timely replacement of running shoes should be stressed tomaintain appropriate cushioning and control. The predominant industryrecommendation has been to replace shoes approximately every 300 miles or6 months; however, Bates and Stergiou [10] suggested that study ndings arevariable on this point. It is important to keep in mind that breakdown canoccur more or less rapidly, depending on weight, weather conditions,terrain, and other factors.

Objective evaluation

Gross evaluation of gait

Initial objective evaluation should start with observation of gait while thepatient is wearing shoes as well as in bare feet. Several laps up and down a longhallway should be observed, while focusing on one area of the body at a timefor each lap. Watch for asymmetries, abnormal compensation, and anyobvious deviation in any plane from a smooth and ecient gait. Examplesof obvious deviation include excessive frontal plane motion of the trunk,excessive lumbar lordosis, asymmetrical arm swing, decreased transverseplane motion of the pelvis, obvious hip internal rotation associated withfemoral anteversion, rapid and excessive internal rotation at the knees, earlyheel rise (typically associated with greater vertical displacement of the head),excessive out toeing/in toeing, excessive rearfoot eversion in midstance,medial/lateral heel whip, or a wide base of support. Also, listen for an abnor-mally loud gait, which often correlateswith observation of a supinatory gait as

814 YAMASHITAa result of the decreased shock absorption that is aorded by this gait pattern.These same issues should be assessed with evaluation of running gait,

keeping in mind the previously outlined dierences between walking and

running. A treadmill and a camera with slow motion capability are helpfulfor breaking down running gait because of the speed at which motionoccurs; however, in the context of an oce visit, a few trips down thehallway should reveal the more obvious compensations. Patients who havehistory and evaluation ndings that are suggestive of biomechanical issues,but more subtle gait deviation on visual assessment, are obvious candidatesfor more formal biomechanical evaluation.

This is especially important when the practitioner recognizes that someobservable structural issues may or may not correlate consistently witha particular gait pattern because people have varied compensatory strategiesfor the same structural issues. Similarly, issues, such as a hallux valgusdeformity, can stem from a wide variety of root causes. The primary issue isexcessive pronation late during the propulsive phase; however, this canoccur with an extremely pronatory gait, or with a supinatory gait that shiftsinto abrupt pronation late during the propulsive phase to inuence thereturn of the center of gravity to a more midline position.

The specialist in biomechanical evaluation observes gait deviations andassesses the patient for specic contributory issues. Gait evaluation, in thecontext of this article, should alert the practitioner to any obvious gaitdeviations while walking and running, and should establish recognition ofa tendency toward excessive pronation, supination, or a neutral gait. Withexperience, this also gives rise to an awareness of possible biomechanicalfactors which contribute to pathologic compensations.

Simple weight-bearing tests

Weight-bearing tests can reveal a great deal about planes of dysfunction.When asking the patient to perform a single leg squat (Fig. 14A) or tomaintain single leg stance (Fig. 14B), watch for quantity of movement andquality of movement at the ankle, knee, hip, and lumbar spine. This revealsstrategies to aect stability or to compensate for weakness or motionrestriction. Also note any pain complaint. Typical compensation can includethings, such as trunk lean and clawing of the toes. Also, watch fora tendency for the knee to shift into valgus and internal rotation, whichoften is concurrent with a tendency to adduct the hip in the case of anexcessive pronator. Conversely, a supinator tends to lack motion intoweight-bearing dorsiexion and compensates with weight bearing back ontothe heels with a concurrent forward lean of the trunk. A tendency to weightbear onto the lateral edge of the foot also is noted.

Other weight-bearing tests include single leg stance reach tests with theupper extremity or nonweight-bearing lower extremity in various directions(Fig. 15), while watching for quantity and quality of movement. Sit to stand

815SHOE WEAR AND ORTHOSES FOR RUNNERS(Fig. 16) and stand to squat tests (Fig. 17) can be performed with an eye forarch and rear foot motion and excursion. The same areas also can beobserved with heel raises. Standing trunk rotation testing (Fig. 18) should

result in immediate ipsilateral supination at the foot and contralateralpronation. Although many dierent tests can reveal a tremendous amountof information about patient movement strategies, it is important to assesswhich tests provide the most pertinent information within the limited timethat is available for evaluation. The most obvious strategy is to use the teststhat challenge the patient to function in the most likely planes ofdysfunction, based on the subjective evaluation and gait analysis.

Standing evaluation

The static weight-bearing examination also reveals valuable informationabout positional deformity, compensated positions, exibility, and otherfactors that are pertinent to function. Initially, the overall structure shouldbe observed from all sides while looking for any obvious deviations ofstructure in any plane. Any signicant weight issue, whether due to obesityor simply a larger frame, should be noted because of the additional load thatis placed on joints that are less than ideal in orientation, as well as thelikelihood of more rapid breakdown of shoes. Obvious static structuralassociations with pronatory stress include an abducted forefoot position,signicant inferior excursion of the arch in nonweight bearing versus weightbearing, an everted rearfoot position in relaxed standing (compensation for

Fig. 14. (A) Single leg squat. (B) Single leg stance.

816 YAMASHITAa forefoot varus deformity), tibial varum, genu varum, and genu valgum.Observable deviations that are associated with supinatory stresses includean adducted forefoot position, an inverted rearfoot position, and pes cavus.

One extremely important weight-bearing assessment is that of passivehallux dorsiexion. This relates to the windlass mechanism in which thehallux undergoes passive dorsiexion after heel o, and thus, tensionsthe plantar fascia, elevates the arch, inverts the calcaneus, approximatesthe heel to the forefoot (Fig. 19), and increases midfoot stability whiledecreasing tension in the ligaments of the midfoot [11]. If the STJ remainsexcessively pronated during late stance, midfoot ligamentous stress is

Fig. 15. (AE) Single leg stance reach tests with upper and lower extremities.

817SHOE WEAR AND ORTHOSES FOR RUNNERSincreased, and hallux dorsiexion is inhibited because the midfoot remainspronated and unstable. In this scenario, the arch fails to elevate and theperoneus longus is in a disadvantaged position, and, thus, is unable toplantarex and stabilize the rst ray to the ground [4,12,13]. Consequently,

passive hallux dorsiexion is unable to overcome the force that isexerted by pronatory tensioning of the plantar fascia. Michaud [14]further described the additional inability of peroneus longus to dorsiexand evert the cuboid; this results in failure to maintain calcaneocuboidjoint stability during propulsion. This illustrates the importance of

Fig. 15 (continued )

818 YAMASHITAassessing in nonweight-bearing and weight-bearing positions because ofthe compensations that may only be obvious when the foot is on theground.

Strength tests

Standard lower extremity strength testing is an important evaluationtool. It oers information regarding deciencies in strength that maycontribute to gait pathomechanics. Conversely, gait pathomechanics canput lower extremity musculature at a disadvantage and lead to patterns of

Fig. 16. (A,B) Sit to stand test.

819SHOE WEAR AND ORTHOSES FOR RUNNERSFig. 17. (A,B) Stand to squat test.

weakness as a consequence. Typical weakness that is associated with anexcessively pronatory gait includes posterior tibialis, tensor fascia lata, andgluteus medius weakness. When observed, the question of source versus

Fig. 18. (AC) Standing trunk rotation test.

820 YAMASHITAsymptoms must be addressed. Did the weakness allow excessive pronationor did a structural issue lead to compensatory pronation, and thus, put thesemuscles at a disadvantage?

Flexibility tests

Assessment of exibility also is important in that if adequate exibilityfor normal gait is not present, the body is forced to compensate (eg, iftalocrural joint dorsiexion is restricted, dorsiexion occurs through thenext joint that allows a large component motion of dorsiexion, in this case,the oblique axis of the MTJ). The result of this compensatory gaitineciency is a greater likelihood of injury.

Nonweight-bearing observation

In addition to the standard and specic functional evaluation, thenonweight-bearing examination can oer valuable information to thepractitioner. The nonweight-bearing arch height can be observed andcompared with that observed in weight bearing, leg length discrepancy can

Fig. 19. (A,B) The windlass mechanism. Representation of arch elevation associated with

passive hallux dorsiexion.

821SHOE WEAR AND ORTHOSES FOR RUNNERSbe assessed, and the presence of tibial and femoral torsions can be evaluated.Hallux dorsiexion range in nonweight bearing can be assessed andcompared with available range in weight bearing to determine the dierence

between a functional hallux limitus that is due to impairment of the windlassmechanism, and a true hallux limitus or rigidus.

When observing the plantar aspect of the foot, the presence of calluspatterns should be noted, and the presence of skin folds over the plantaraspect of the feet (an indication of hypermobility) can be observed.Additionally, recognition of ankle or forefoot equinus deformity, presenceor absence of a plantarexed rst ray, and forefoot varus or valgusdeformity can be appreciated in prone with the STJ maintained in neutral.Assessment of these issues can help the provider to recognize the reasonsbehind any gait deviations or functional compensations that are observedduring the weight-bearing aspects of evaluation.

Clinical decision making

Following physical examination of the patient, the practitioner shouldhave a basic idea of whether the patient tends toward a pronatory,supinatory, or neutral gait. In addition, recognition of some of the factorsthat contribute to gait deviation should be obvious. The next step is toevaluate the severity of any gait pathomechanics and decide what type ofshoe should be prescribed to the patient and whether an over-the-counter orcustom orthosis would be helpful.

As any experienced practitioner knows, the most important issue intreating any pathology is recognition of the source versus the symptoms.The chronicity of pathology in the runner who has biomechanical issuesmay point to a history of only focal symptomatic treatment. This can beeective transiently; however, without addressing the distal or proximalcause of the oending pathomechanics, recurrent injury or pain is inevitable.

The excessive pronator

Typical signs and symptoms

Excessive pronators present with a broad range of pathology (Box 1). Theycan be plagued by a variety of injuries in dierent areas, or experience chronicinjury of the same structures. This depends on compensatory strategies andthe integrity of the areas that are inuenced by pronatory dysfunction at anypoint in time. Again, the key feature to watch for with any biomechanicalissue is chronicity.

Often, the overpronator presents with early, excessive, and prolongedpronation which results in characteristic callus patterns. Ordinarily, a pinchcallus over the medial hallux can be observed, which is due to the patient

822 YAMASHITApropelling medially over a functional hallux limitus, as well as diusecallusing over the ball of the foot. In this situation, hallux dorsiexion islimited because of the pathologic inuence of prolonged pronation on thewindlass mechanism. Additionally, when the STJ remains pronated through

the propulsive phase of gait, the MTJ fails to lock and the peroneus longusis placed at a mechanical disadvantage. Therefore, instead of providinga plantarexion force to maintain rst ray stability for propulsion, theperoneus longus allows the ground to push the rst ray up into dorsiexion;this results in excessive loading of the other metatarsals. Consequently,callusing over the second, and sometimes, the third and fourth metatarsalheads can be observed.

Other issues that often are present include weakness of hip abductors andexternal rotators, as well as peroneus longus and posterior tibialis, due tothe excessive loads that are placed upon these structures by this inecientgait pattern.

Contributing factors

Structural issues that contribute to excessive pronation include rear footvarus deformity, forefoot varus deformity, equinus deformity, tibial orfemoral torsion, and genu varus or valgus. Common contributory exibilityissues include TCJ dorsiexion restriction and functional forefoot varus orsupinatus [15,16]. The latter is a supinatory soft tissue restriction along thelong axis of the MTJ which mimics the osseous forefoot varus deformity.

Appropriate shoes/orthoses

Depending on the severity of overpronation, stability shoes or motioncontrol shoes are indicated. In the case of the moderate to severe

Box 1. Typical pathology of the overpronator

Stress fractureNeuromaHallux abducto valgusAchilles tendonitisMedial tibial stress syndromeAnterior shin splintsTarsal tunnel syndromePatellofemoral trackingPatellar tendonitisPes anserine tendonitis/bursitisIliotibial band tendonitisSacroiliac joint pathologyLumbar spine pathology

823SHOE WEAR AND ORTHOSES FOR RUNNERSoverpronator, a motion control shoe is preferred. If there are not multipleareas of involvement and there is not a history of chronic injury with activity,an over-the-counter arch support may be helpful in slowing excessive midfoot

compensation in the mild overpronator. If, however, the patient hasexperienced a variety of symptoms over the course of his/her running career,if there is an issue of chronicity, or if obvious structural issues are dictatingfunctional compensation, a formal biomechanical evaluation should bepursued. Custom biomechanical orthoses, which are fabricated based onevaluation by a knowledgeable practitioner, should facilitate normalizationof running mechanics, and thereby, assist in the resolution of the presentingissue and decrease the likelihood of injury in the future.

The supinator

Typical signs and symptoms

The supinator is characterized by a gait pattern that lacks shockabsorption. Because the STJ remains inverted through much of the stancephase, the midfoot remains sti and fails to assist in cushioning the impactthat is associated with early stance. Typically, this is a loud gait because ofthe abrupt rate of loading. This gait pattern often is marked by callositiesover the rst and fth metatarsal heads in the case of a forefoot valgusdeformity. In this case, the forefoot sits in valgus relative to the rearfootwhen the STJ is in neutral; as the forefoot loads, the rst ray contacts theground rst and forces the STJ to compensate into an inverted position.Consequently, the fth metatarsal head loads rapidly, only to shift abruptlymedially as the STJ pronates to shift the center of gravity back towardmidline at heel o [17]. This appears as a lateral heel whip.

The tenuous balance that is aorded by the rate and duration of lateralcolumn loading, as well as the lack of shock absorption that is associatedwith this gait pattern results in the characteristic array of pathology that isnoted in Box 2.

Contributing factors

The typical supinator has a high arched foot which tends to be sti anda forefoot valgus deformity often is present. It also is common to seea concurrent rigid plantarexed rst ray.

Another scenario is the uncompensated forefoot varus deformity inwhich the STJ lacks adequate eversion to compensate for the varus positionof the forefoot. This foot type maintains a supinated position throughstance phase with the lateral foot remaining loaded late into the propulsivephase; this creates a characteristic callus pattern along the lateral border ofthe foot. This necessitates an abrupt shift of the center of gravity towardmidline during terminal stance which sharply loads the medial hallux.

Obviously, this tenuous balance, which is provided by weight bearing on

824 YAMASHITAthe lateral aspect of the foot, is exacerbated in a patient who hasa concurrent tibial or genu varum because of the absence of pronatorycompensation in the STJ.

Appropriate shoes/orthoses

The issue with the supinator is to facilitate motion and shock attenuation.The shoe of choice, therefore, is the cushion shoe. Cushion insoles also maybe helpful; however, if an obvious structural issue contributes to this gaitpattern, as well as chronic pathology, a custom device is essential.

The neutral runner

The neutral runner tends to visit the clinic primarily as a result of trauma,inappropriate training progression, terrain issues, exibility issues, orweakness. A stability shoe with a good combination of motion controland shock absorption is appropriate for this type of runner, but a cushionshoe also may be well-tolerated. Considerations should include mileage,terrain, and body weight when selecting more or less stable shoes on thespectrum.

Evaluating the orthosis

When evaluating the orthoses of a patient who arrives in the clinic for therst time, gait and quality of functional weight-bearing test performanceshould be observed. Next, the contour of the device should be observed andmatched to the nonweight-bearing foot in a neutral STJ position. A

Box 2. Typical pathology of the supinator

Chronic ankle sprainsSublexed peroneal tendonsPlantar fasciitisMetatarsalgiaStress fracturesHammer toesClaw toesHaglunds deformitySesamoiditisPeroneal tendonitisIliotibial band tendonitisSacroiliac joint pathologyLumbar pathology

825SHOE WEAR AND ORTHOSES FOR RUNNERScommon casting error is to capture the contour of the foot in a compensatedposition, which, for the overpronator, means that the device contour will belower than the arch when assessed in the manner that was described

previously. Cursory evaluation, based on the previous sections should beperformed to assess the sources of weight-bearing pathomechanics, as wellas to evaluate how well the devices resolve the compensatory mechanics.Full correction to an idealized gait is not necessarily the goal, but rather,gait pathomechanics should be controlled well enough to facilitate thepatients ability to function without an injury-inducing level of stress.

The combined eect of the orthosis and the shoe also needs to beconsidered when evaluating function. An aggressive device with motioncontrol shoes may overcorrect a mild to moderate pronator, whereasa cushion shoe or a 2-year-old motion control shoe fails to provide anappropriate platform for comfort and function of a severe overpronator,even with appropriate orthoses.

One must recognize that orthoses inuence major changes in the patientsweight-bearing environment and that they generally do not feel completelycomfortable for several weeks. This emphasizes the importance of a gradualbreak-in process with wearing time increasing by 1 to 2 hours per day,depending on tolerance. Diuse arch soreness and general lower extremitymuscle soreness is to be expected, but joint pain in the lower extremity orspine indicates that the device may require alteration. Additionally, if thepatient reports return of symptoms following a period of initial relief withthe devices, undercorrection may be the problem. Referral back to thedispensing provider in each of these cases often results in a quick andeective resolution to the problem.

Devices for the excessive pronator

When evaluating a custom device for the overpronating runner, the mostobvious issue is whether the device is addressing the source of the problem.For example, if the structural issue is a forefoot varus deformity, the postingshould extend to the sulcus, just beyond the metatarsal heads to control theforefoot position through the propulsive phase. If, however, the rearfoot isthe sole issue, a standard length device that extends only to the regionbehind the metatarsal heads is adequate, as long as the rearfoot varusdeformity is addressed appropriately (Fig. 20). Forefoot posting is notnecessary in this circumstance, but a deep heel seat is an extremely helpfultool in the overpronator to control excessive rearfoot motion that is due toSTJ compensation.

Another common issue that drives excessive pronation is one ofstructural deformity that is extrinsic to the foot, such as tibial varum orfemoral anteversion. This type of deformity exerts inuence throughout thestance phase of gait and must be addressed accordingly, with posting

826 YAMASHITAmaterial used in the rearfoot and extending forward to the sulcus. Acommon error is to post standard length for a patient who has extrinsicissues or forefoot varus issues. This results in abrupt pronatory pathome-

chanics late during the propulsive phase, which force transverse planecompensation proximally. This abrupt internal rotation results in increasedmedial stress to the knee and lateral stress to the hip, which can aect theplantar fascia, pes anserine and trochanteric bursae, and the sacroiliac andlumbar zygapophyseal joints.

Devices for the supinator

In the case of an uncompensated forefoot varus, a softer device withmedial forefoot posting to address the deformity can help to decrease thelateral instability by distributing the forces through the entire foot versustenuously on the lateral aspect. With the forefoot valgus, a standard lengthdevice with a few degrees of forefoot valgus posting can facilitate morenormal pronation by building the ground up to the lateral side of the foot. Arst ray cut-out takes away material where the rst metatarsal head hits thedevice. This allows for more time before the rst ray contacts the groundand, thereby, decreases STJ compensation into supination as forefootloading occurs. Rearfoot control also must be considered, using a deep heelseat to control the rearfoot in preparation for forefoot loading as well.

Fig. 20. (A) Standard length orthotic. (B) Orthotic posted to the sulcus.

827SHOE WEAR AND ORTHOSES FOR RUNNERSSummary

Many patients have been t with orthoses and arrive to the clinic statingthat their symptoms failed to resolve, or were even worse with use of the

devices. Upon further questioning, they reveal that they may or may nothave been evaluated thoroughly, according to the areas of evaluation thatwere explored in this article. Furthermore, they may have been casted inweight bearing, and often by a technician, instead of the medical provider.They usually have no awareness of having been maintained in a neutral STJposition for casting and generally remark that they were not educated at allregarding the contributory factors for their particular gait pathomechanicsor pathology.

Providers who dispense custom foot orthoses include physicians, physicaltherapists, podiatrists, pedorthotists, and chiropractors. Because of thenumber of disciplines that consider foot orthoses as part of their scope ofpractice, the presence of a frustrating lack of uniformity with respect toknowledge base, evaluation skills, casting skills, and treatment philosophywithin this population is understandable. Even the language that is used todescribe positions, motions, deformity, and pathology vary based onspecialty and specic training. Not surprisingly, unacceptable disparities arepresent, even within the same disciplines. This huge variability underminesthe credibility of those practitioners who thoughtfully and deliberatelyfabricate devices based on sound biomechanical principles. It behooves thereferring provider, as well as his/her patients, to know the background of,and the evaluation procedures that are used by, the practitioner who will beevaluating the patient for custom foot orthoses.

References

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[13] Root ML, Orien WP, Weed JH. Normal and abnormal function of the foot. Los Angeles

(CA): Clinical Biomechanics; 1977.

[14] Michaud TC. Ideal motions during the gait cycle. In: Foot orthoses and other forms of

conservative foot care. Newton: Thomas C. Michaud; 1997. p. 2756.

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conservative foot care. Newton: Thomas C. Michaud; 1997. p. 18192.

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829SHOE WEAR AND ORTHOSES FOR RUNNERS

Evaluation and Selection of Shoe Wear and Orthoses for the RunnerThe importance of the subtalar joint/midtarsal joint relationshipNormal pronationNormal supinationRunning versus walkingShoe anatomyShoe typesCushion shoesStability shoesMotion control shoes

Anatomy of the orthosisTypes of devicesImportance of appropriate casting techniqueThe subjective evaluationObjective evaluationGross evaluation of gaitSimple weight-bearing testsStanding evaluationStrength testsFlexibility testsNonweight-bearing observation

Clinical decision makingThe excessive pronatorTypical signs and symptomsContributing factorsAppropriate shoes/orthoses

The supinatorTypical signs and symptomsContributing factorsAppropriate shoes/orthoses

The neutral runnerEvaluating the orthosisDevices for the excessive pronatorDevices for the supinatorSummaryReferences