Podiatric Management in Ice Skating - AAPSM climate and ice hockey teams ... Podiatric Management in Ice Skating Understanding the biomechanics of this sport can help you better treat

NOVEMBER/DECEMBER 2003 • PODIATRY MANAGEMENTwww.podiatrym.com 49

This article is the second in a seven-part sports podiatry series written bymembers of the American Academy ofPodiatric Sports Medicine. This sport-specific series is intended as a practical“how-to” primer to familiarize you withthe specific needs of patients who partici-pate in these sports, and the types of in-juries and treatment challenges you’relikely to encounter.

Ice skating in all its various formshas shown increased popularityworld wide. Olympic speed skating

champions are coming from areas ofwarm climate and ice hockey teamsare starting up in almost every popu-

lated geographical location. A closecousin to ice skating is in-line skat-ing, which is a similar biomechanical

activity and is another commonrecreational and fitness endeavor.The increasing popularity of skating

makes it likely that all podiatric prac-titioners will benefit from a funda-mental understanding of the man-agement of this athletic population,regardless of practice location.

Ice skating involves three disci-plines: figure skating, speed skatingand power skating. It is power skat-ing that defines the unique skatingpatterns and mechanics of locomo-tion seen in ice hockey. The princi-ples of podiatric biomechanics canbe applied to all of these skatingdisciplines, as many of the mechan-ics of foot position and balance aresimilar. For the purposes of this ar-ticle, however, I will focus on thebiomechanics of power skating.

By R. Neil Humble, D.P.M.

Continued on page 50

Podiatric Management in Ice Skating

Understanding the biomechanics of this sport can help you better treat skaters.

S P O R T S P O D I A T R YS P O R T S P O D I A T R Y

Both walking andskating are biphasic

movement patterns thatconsist of periods of

single and double-limbsupport.

that may arise, it is first helpful tocompare power skating with themore commonly understoodbiomechanics of walking. Bothwalking and skating are biphasicmovement pat-terns that consistof periods of sin-gle and double-limb support. Bycomparison, it isthe support phaseof walking thatbecomes the skat-ing glide. One as-pect of skatingthat makes itunique in the sup-port phase is thatthe friction on theperformance surface is much lessthan that seen in most walking activ-ities. As a result there are decreased

posterior linearshear forces withtouchdown due todecreased frictionand decreased ante-rior linear shearforces in the latemidstance topropulsion stage.This low frictionsurface will neces-sarily impart a needto abduct the footby external hip ro-tation at propul-sion.1 The center ofgravity thereforedoes not progress ina linear sinusoidalpath over the footas seen in walking,but rather theskater and his/her

Biomechanics Power skating in hockey in-

volves skating forward, backwardand with multiple directionalchanges as the game evolves. It isthis ever-changing movement pat-tern that makes this activity diffi-cult to study from a biomechanicalstandpoint. It is forward accelera-tion and striding, however, that arethe most consistent and studied as-pects of power skating. The podi-atric assistance in foot and lowerextremity balance on top of a nar-row balance point, the skate blade,will allow a practitioner to assist inboth improved performance andoveruse injury patterns.

In order to better understandthe biomechanics of power skatingand the clinical injury perspectives

center of gravity move in an oppositedirection to the weight bearing skate.

The acceleration in power skat-ing is divided into two uniquestride patterns, the first three

strides and thefourth stride,known as thetypical skate cut.2

The first stridepattern usuallyinvolves the firstthree strides. Itlasts approxi-mately 1.75 sec-onds, involvescontinual posi-tive accelerationand has a negligi-ble or non-exis-

tent glide phase.3 It is during thisstride pattern that the skater oftenappears to be “running” on his/herskates.

The second stride pattern oftenbegins on the fourth stride and isconsidered the typical skate cut.2

This stride pattern consists of peri-ods of positive and negative accel-eration and involves three phases.It starts with a glide during singlelimb support which imparts nega-tive acceleration.4 It continues withpropulsion during single limb sup-port which is accomplished by ex-ternal rotation of the thigh and theinitial extension movements of thehip and knee.5 This stride patternconcludes with propulsion duringdouble limb support. During thisphase the second limb acts as a bal-ance point to complete propulsionthrough full knee extension, hyper-extension of hip and plantar flex-ion of the ankle.

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50 www.podiatrym.comPODIATRY MANAGEMENT • NOVEMBER/DECEMBER 2003

Figure 1: Ice hockey, power skating.

The most common footand lower extremity

injury patterns seen inice hockey are acute

traumatic events.

Circle #112

Clinical Injury Perspective Without a doubt the most com-

mon foot and lower extremity injurypatterns seen in ice hockey are acutetraumatic events. However, for thepurposes of this article we will focuson the more common presentingproblems in an office setting. Thereis, first, the common dermatologicconditions seen in this patient popu-lation. Second, there are the intrinsicfoot-to-boot injuries that can be pre-cipitated from the nature of theunique footwear, and last, there arethe specific biomechanically-pro-duced clinical injury patterns thatmay arise from overuse.

A general understanding of skateanatomy and fit is necessary for a fullunderstanding of the impact of com-mon podiatric pathologies, as well asfor an understanding of the biome-chanically-produced overuse injuriesseen in the skating population. Thereis first the skate boot that is rigid forprotection and support.

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Figure 4: Skate Anatomy

Circle #5

boot itself. The attachment of theblade housing to the boot can be apoint of biomechanical input. Thishousing can be moved medial tolateral, or anterior to posterior onthe boot. Its standard position isto hold the blades centrally underthe heel to continue forwardunder the second metatarsal headand further forward through thesecond digit. The blade housingcan also act as an attachment site

Sewn skates generally fit one toone and a half sizes smaller thanone’s regular shoe size. Skates needto fit snugly and toes should“feather” the toe cap. All bootshave a heel raise that may be fromfive degrees to nine degrees butcan vary from one manufacturer toanother. Next is the blade housingthat is riveted or screwed onto the

for heel lifts and wedges as theyare sandwiched between the hous-ing and boot. Lastly is the narrowblade, which can also be adjustedfor biomechanical effect. It is rock-ered front to back and is hollowground on the bottom surface tocreate a medial and lateral edge orbite angle. The blade acts as a bal-ance point and as little as one inchis all that normally contacts theice surface.

As mentioned above, skates needto fit snugly, and as such manyskaters wear their skates withoutsocks for a better “feel.” This prac-tice should be discouraged due tothe dermatological consequencesfrom both friction and hygiene. Blis-ters, corns, callouses, tinea pedis,onychomycosis, and verrucae arecommon in this patient population.

Use of general podiatric principlesalong with a thin, well-fitting per-formance sock with both hy-drophilic and hydrophobic proper-ties will decrease friction within theboot and improve hygiene. If thinenough, it will still allow the “feel”needed for performance.

The specificity of the footwearand its need for a performance fitcan also cause friction and pressureinjuries at the interface betweencommon structural foot deformitiesand the boot. Common podiatricpathologies such as hammertoesand bunions are a painful dilemmain this footwear and are treated inthe usual fashion. Haglund’s defor-mity, however, is an especially dif-ficult problem for skaters.

Other than traditional podiatrictreatments one may alleviate theskate counter pressure with internalor external heel lifts, accommoda-

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tive adhesive felt padding withinthe skates, or expansion of the heelcounter by a local skate shop. Awell-posted custom foot orthoticcan also decrease the movement ofthis prominence within the skate.The tight fit of skates can also in-crease the incidence of Morton’sneuroma and dorsal superficialcompression neuropathies.

Proper boot structure, alongwith the necessary biomechanics ofskating, can decrease the frequencyof complaints from certain patholo-gies. Hallux limitus, Achilles ten-donopathy and plantar fasciitis areall less commonly a problem dur-ing skating activities.

Biomechanical ly-producedoveruse foot and ankle clinical in-jury patterns can clearly be identi-fied in ice skating. The narrowblade or balance point creates needfor strenuous eccentric muscle con-trol and proprioceptive skills to as-sist in balance over this small bal-ance point. As a result, general footfatigue from strain of the small in-trinsic muscles of the foot are com-mon. As well as the intrinsic mus-cle strains, there are the extrinsictendonopathies that can occur inthe posterior tibial tendon and theperoneal tendons and muscles as areaction to the need for balance.

In comparison to other sportingactivities, power skating shows a de-crease in the number of contact phaseinjuries due to the low friction of theice surface. The overuse injuries in thelower extremity usually show upmore proximally in the groin or lowback due to the inherent need forskate and skater to be moving in op-posite directions as propulsion occurs.Groin injuries in the adductor musclegroup (adductor magnus, longus andbrevis) occur when the thigh is exter-nally rotated and the hip is abducted,thus putting this muscle group undermaximal strain. Dr. Eric Babins fromthe University of Calgary has reporteda reduction in pain of the lumbarspine and lower extremity along withimproved performance with properfitting of skates, blade alignment andadjustment for leg length discrepan-cies as required due to the improvedbiomechanical balance above theskate blade.



Figure 6: Haglund’s deformity and counter expansion.

lower extremityand foot examneeds to be doneas would be donefor any athleticpopulation, and adecision on footorthotics can bemade using soundRoot biomechani-cal techniques.6

These techniquesof forefoot to rear-foot and rearfootto leg control willhelp to compensate for biomechan-ical faults, help stabilize the subta-lar and midtarsal joints, and helpmaintain sound structural align-

Clinical Biomechanical Balance There are two steps in the pro-

cess to assist a skater from a biome-chanical perspective. The first is thepositioning of the foot within theboot using standard podiatricbiomechanical principles. The sec-ond is the balance of the bladeonto the boot itself.

Step 1: Foot balance withinboot—custom foot orthotic.

A general podiatric clinician canbe confident when dealing with thefirst step of biomechanical control,which is positioning the foot prop-erly within the boot. A complete

ment of the lower extremity fromthe midtarsal joint to the hip, pro-viding a solid lever for propulsion.This orthotic can then be improvedupon by using a general under-standing of skating mechanics andapplying the newer techniques offoot orthotic control as discussedby Kirby and Blake.7,8

As a skater is in single-limb sup-port in the early stages of propul-sion, the foot is abducted and thehip externally rotated. The skateand skater are moving in oppositedirections at this time while tryingto balance on the narrow skateblade. As such, the center of gravityis much more medial with respectto the weight-bearing extremity,and even subtle biomechanicalfaults, causing excessive foot prona-tion, will cause a skater to spendtoo much time on the medial skateedge. Power and efficiency are cre-ated by staying on the outside edgeas long as possible early in the typi-cal skate cut. Therefore, maximallycontrolling the medial column ofthe foot with respect to the subtalarjoint axis location can greatly assista skater with this task. Using boththe newer and traditional biome-chanical controlling techniques im-proves skating power and balanceduring propulsion.

Orthotic Design For Skating1. Neutral suspension casts of feet. 2. Trace or send skate insoles

with casts to improve boot fit. 3. Intrinsic forefoot posting un-

less custom added-depth skateboots are used.

4. Standardly, invert casts 10degrees using Blake technique toincrease medial arch contact andto increase time spent on lateral

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Figure 7: Skate Orthotic

About The American Academy ofPodiatric Sports Medicine

The American Academy of Podiatric Sports Medicine is thesecond largest affiliate of the American Podiatric Medical Associa-tion. Over 150 of its 500 plus members have achieved Fellowshipstatus in the AAPSM.

The AAPSM has a major goal of advancing the understanding,prevention and management of lower extremity sports and fit-ness injuries. The AAPSM believes that providing such knowledgeto the profession and to the public will optimize enjoyment andsafe participation in sports and fitness activities. The AAPSM ac-complishes this mission through professional education, scientificresearch, public awareness and membership support.

The AAPSM has long been the organization looked to by thepublic and media for authoritative information on all aspects ofpodiatric sports medicine. Members of the AAPSM have alldemonstrated significant interest in podiatric sports medicineand are sought out by athletic trainers, teams, and patients alikefor their expertise. In general, members of the AAPSM have ex-tremely busy practices and attract patients who are physically ac-tive and have a commitment to health and wellness.

One of the most popular sources the AAPSM has available isthe website (www.aapsm.org.), which offers information to thepodiatric profession as well as the general public. The most popu-lar section of the website is the AAPSM shoe evaluations. TheAAPSM evaluates over 100 shoes each year in over 15 categoriesand they are posted on the AAPSM website.

Any practicing podiatrist with an interest in sports medicineshould become a member of AAPSM. Join other AAPSM memberswho are dedicated to promoting the AAPSM mission statement aswell as demonstrating to their own patients that they have made acommitment to this practice specialty. If you are interested in be-coming a member, please contact Rita Yates, AAPSM Executive Di-rector, at [email protected] or call toll free at (888) 854-FEET.

For more information, circle #196 on the reader service card.


blade edge. Increase as clinically justified. 5. Standardly, use a 3-4 mm medial heel skive

cast modification to help with lateral edge control.Increase as clinically justified.

6. Polypropylene shells are preferable as they canbe more easily modified as needed to the medial shankof the skate boot.

7. Extrinsic rearfoot posts work if well-skived to fitin the heel counter of boot and use a thin cap to de-crease heel lift. There should be no motion allowed for

in the rearfoot posting. 8. Use full-length extensions with thin top cover

materials of good friction next to the foot for grip and“feel.” A thin layer of firm Korex under the extensionwill decrease forefoot irritation from blade housingmounting rivets in the boot.

9. Some skaters like buttress or toe crest pads builtinto the extension for their toes to grip onto.

Step 2: Blade Balance The second step in mechanically helping skaters in-

volves blade balance. Blade balance is accomplishedusing three different techniques: sagittal plane rocker,medial-lateral position of blade, and varus/valgus wedg-ing of blade, which can incorporate limb lifts. These in-terventions are usually best performed by a professionalskate mechanic after podiatric advice is given.

The sagittal plane rocker of the blade allows for easy re-sponse to the center of gravity changes in the sagittal plane.Standardly, the rocker is in the centre of the blade with onlyone inch of the blade in contact with the ice. Some skaterswill increase their rocker (decrease contact with ice) in order

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Figure 8: Sagittal plane rocker.

individual preference for performance,and should only be done in the handsof a skilled skate technician.

The medial-lateral position of theblade on the boot has a significant ef-fect on a skater’s posture and bal-ance. The standard blade placementis longitudinally from heel center tothe second metatarsal head, and sec-ond digit. This blade position shouldprovide an inherently stable platformfor the foot to sit with pure sagittalplane rocking.

A medially deviatedsubtalar joint axis will in-fluence the default contactportion of the standardlyplaced blade. Shifting theblade medially will placethe default contact portionof the blade in a morefunctional position with re-spect to the medially devi-ated axis in those patients.See figure 11 and 12. In ex-tremely rigid inverted feet,moving the blade laterallyon the boot will help to

improve balance.Balancing the blade

with wedging is thefinal blade adjust-ment technique. Afteran appropriate orthot-ic has been made, therocker has beenchecked, the bladehas been moved me-dially or laterally asneeded, a decision onusing a wedge can bemade by looking atthe position of theblade edges with respect to the

to improve their maneuverability.Others will decrease their rocker toallow more blade to contact the iceand this will increase speed but de-crease turning capabilities. Adjust-ments of rockers are more a matter of

weight-bearing surface. A wedge canassist in balancing the blade to theboot and upper body so that in staticstance each edge of the blade bal-ances on the ice surface equally. Asodd as it may seem, a supinated orvarus foot can require a medialwedge to bring the medial blade edgeevenly to the ground. A pronated orvalgus foot can require a lateralwedge to bring the lateral blade edgeto the ground. (See figures 13 to 15.)

The podiatric management of theskater can be best shown through aseries of case examples. Each of thesescenarios depicts the management ofincreasingly complex cases involvingboth foot-to-boot balance and blade-to-boot balancing techniques.

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Figure 9: Standard blade placement.

Figure 13: No wedge needed.

Figure 14: Supinated or lower extremity varum-medial wedge.

Figure 12: Shifting the blade medially willput it in a more functional position.

Figure 11: Standard blade placementcompared to STJ axis.

Figure 15: Pronated or lower extremity valgum-lateral wedge.

Figure 10: Standard blade placement, poste-rior view.


The first goal in treat-ment was a daily orthot-ic to relieve his symp-toms and the secondarygoal was a skating-specif-ic orthotic to improvehis skating performanceand his enjoyment of hisrecreation. Thepolypropylene skatingorthotic was made froma neutral suspension castwith reduction of thesupinatus. The casts were modified

Case #1—Moderate Pronation Ten year old white male suffers

from medial arch and heel painpredominantly in his day-to-dayactivities, which carries over intohis recreational hockey. He is other-wise fit and healthy and has beendiagnosed with plantar fasciitis.

A complete podiatric biomechani-cal exam was performed and the per-tinent results were a two degree fore-foot varus and a four degree forefootsupinatus bilaterally.

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Figure 16: Case #1, Moderate pronation.

Figure 17: Case #1, moderate pronation. Figure 18: Case #1, moderate pronation.

the orthotic. A functional skate or-thotic with maximal control wasused to assist this patient, along witha good-quality and well-fitted skateboot. No blade adjustments wereneeded, and the blade was left in itsstandard default position.

with 10 degrees of inversion, and a 3mm. medial heel skive. The forefootwas posted intrinsically 2° varus afterthe inversion cast modification, anda rearfoot post was added to balance

Case #2—Moderate-SeverePronation

Twelve year old male suffersfrom medial ankle and knee painwhile playing hockey. He is other-

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Figure 19: Case #2, Moderate-severe pronation.

Figure 20: Case #2, skate orthotic.

Figure 21: Case #2, blade adjustment.

Figure 22: Case # 2, end results.


wise fit and healthy. After a complete history andphysical examination, a diagnosis of posterior tibialtendon strain and patellofemoral pain syndrome wasmade. The primary etiology of his problems wasdeemed to be biomechanically produced from exces-sive foot pronation. He functions maximally pronateddue to a fully compensated forefoot and rearfoot varusdeformity bilaterally of approximately four degrees forboth.

A custom foot orthotic was manufactured fromcasts corrected to 25° of inversion using the Blake in-version technique and a 4 mm. medial heel skive wasadded. The forefoot to rearfoot was posted a further 4°of varus and a balancing post was placed on the rear-foot also in 4° of varus. A further mechanical interven-tion was needed and the blades were moved medially

on the skates.The final solu-

t ion for this pa-t ient was a goodquality skate bootappropriately fit-ted, an aggressivecustom foot or-thotic and a bladebalancing adjust-ment.

Case #3—Supinated PesCavus Foot Type

An 18 year oldWestern Canadian

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Figure 23: Case 3, forefoot valgus. Continued on page 62

Figure 24: Case 3, neutral cast.

Figure 25: Case #3, skate orthotic.

Conclusion Ice skating, and more specifi-

cally power skating, is showing in-creased popularity throughoutNorth America. All podiatric prac-titioners can expect to see iceskaters in their offices. Podiatricbiomechanical management usingboth traditional and newer tech-niques used in other athletic popu-lations can be modified to work inthe athletic skating population.The sound use of biomechanicalintervention can assist in the plea-sure and performance of thisunique activity.

Many thanks to my partner LeeNugent, D.P.M. for his many dis-cussions on this topic and his artis-tic input with diagrams. Thanksalso to Jamie Wilson of Graf Cana-da for his assistance with blade bal-ancing techniques.

Bibliography:1 Roy B: Biomechanically features of

different starting positions and skatingstrides in ice hockey. In Asmussen E,Jorgenson K (eds): Biomechanics V1-B.

Hockey League player suffers fromlateral leg and ankle pain, as well asskate balance problems. Historyand physical exam finds him other-wise fit and healthy. A diagnosis ofperoneal tendonitis was made dueto a rigid forefoot valgus and alimb-length discrepancy.

The mechanical solution tothis patient’s problem was a cus-tom-made, added-depth skateboot to accommodate an orthoticwith an extrinsic forefoot valguspost to the sulcus. Standard Rootbiomechanical principles wereused to make this orthotic and nonewer inversion techniques wereutilized.

Many blade adjustments wereneeded to assist in this patient’sperformance. A l imb-l i f t wasadded full-length, the blades weremoved laterally on the boots anda medial wedge was inserted toassist further in bringing the me-dial edge of the skate blade downto the ground.

Baltimore, University Park Press, 1978,p. 137.

2 Hoshizaki TB, Kirchner GJ: A com-parison of the kinematic patterns be-tween supported and non-supported an-kles during the acceleration phase offorward skating. Proceedings of the In-ternational Symposium of Biomechan-ics in Sport, 1987.

3 Marino GW: Acceleration time re-lationships in an ice skating start. Res Q50:55, 1979.

4 Mueller M: Kinematics of speedskating. Master’s thesis, University ofWisconsin, 1972.

5 Marino GW, Weese RG: A kine-matic analysis of the ice skating stride.In Terauds J, Gros HJ (eds): Science inSkiing, Skating and Hockey. Del Mar,California, Academic Publishers, 1979,pp. 65, 73.

6 Root ML, Orien WP, Weed JH,Hughes RJ: Biomechanical Examinationof the Foot Volume 1. Clinical Biome-chanics Corporation. Los Angeles, CA.

7 Kirby KA: Subtalar Joint Axis Loca-tion and Rotational Equilibrium Theoryof Foot Function. J AM Podiatr MedAssoc 91(9): 465-487, 2001.

8 Blade RL: Inverted functional or-thosis. JAPMA 76: 275, 1986.

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Dr. Humble is ClinicalAssistant Professor,Department of Surgeryat the University ofCalgary and AssistantProfessor, Faculty ofKinesiology at the Uni-versity of Calgary. He isa Fellow of The Ameri-can Academy of Podi-atric Sports Medicineand of The AmericanCollege of Foot andAnkle Surgeons

Figure 26: Case #3, heel lift.

Figure 27: Case #3, blade placement.

Figure 28: Case #3, medial wedge to balance.

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Podiatric Management in Ice Skating - AAPSM climate and ice hockey teams ... Podiatric Management in Ice Skating Understanding the biomechanics of this sport can help you better treat