The FootLecture 9

The Foot

one of the highest incidence of sport injuries

account for 20 to 25 % of injuries associated with running and jumping sports

Anatomy

26 bones - 14 phalangeal, 5 metatarsals & 7 tarsels

toes function to smooth the weight shift and to help maintain stability during weight bearing

Arches

function to support and distribute body weight from the talus through the foot , changing weight bearing conditions over varying terrain

Longitudinal Arch

from medial border calcaneus to head of 1st metatarsal

arch is higher medially than laterally - medial is usually the point of reference

supported by spring ligament (calcaneonavicular), plantar fascia

tib post. and ant provide dynamic support

Plantar Fascia

is a thick interconnected band of fascia that covers the plantar surface of the foot, providing support for the longitudinal arch

it extends from the calcaneus to the proximal phalanx of each toe

during the weight bearing phase of the gait cycle the plantar fascia functions like a spring to store mechanical energy that is release to help the foot push off from the surface

Transverse Arch

runs across the anterior tarsal (navicular cuboid and cuneiforms)

supported most by bony structure

Joints

1) lnterphalangeal (IP)

PIP& DIP (except 1 st)

hinge joints with support on med and lat collateral , plantar and dorsal surface

2) Metatarsophalangeal (MTP)

condyloid - 2 planes of movement ( flex/ ext, abd/add)

supported by med & lat collat. & plantar and dorsal surfaces

3) Tarsometatarsal

attached base of metarsal to tarsal bone slight gliding in 2 planes (flex/ext ,

abd/add) attached by plantar and dorsal lig

4) lntertarsal

Gliding joints these joints allow the foot to adapt to

uneven surfaces

Foot Mechanics Pronation Supination

a normal amount of pronation is necessary in reducing peak forces sustained during impact

there is a link between excessive pronation and running related injuries

normal pronation 6- 8 degrees

Pronation

Pronation problems. loose and unlocked 2nd metatarsal #, plantar fasciitis, ant/post

tibialis tendinitis, Achilles tendinitis, tibial stress fractures, PFS ( patella

femoral syndrome)

Supination Problems lack of shock absorption inversion ankle sprains , tibial stress

syndrome, peroneal tendinitis, ITB friction syndrome, trochanteric bursitis

Dorsiflexion / Plantar Flexion Motion occurring in the sagittal plane DF – ankle flexion PF – ankle extension

Inversion / Eversion Movements at the subtalar joint Inversion – medial rotation Eversion – lateral rotation

ROM of Ankle

Common Foot Problems and Injuries

Hammer and Claw Toes

often congenital - can be caused by improperly fitted shoes - muscle contractures or malalignment of bony structures

hammer toes involve extension of MTP joint and neutral

position of PIP and flexion at the DIP joint

claw toes are a flexion deformities of DIP and PIP

joint and hyperextension of the MTP joint

both can lead to painful callus formation on bottom of toe or under MT head

surgery is often only solution to severe cases

Turf Toe

Sprain of the plantar capsular ligament of the first toe

Results from forced hyperextension of the first toe

related to artificial turf - lightweight shoes that are too flexible and positions that require forced toe hyperextension ( as football linebackers and offensive lineman)

pain - tenderness - swelling at MTP joint

push off phase of running particularly painful - as with passive extension of great toe

Rx - ice, protection from excessive motion (taping) - or stiff -soled shoe

decrease activity - particularly running

Common Fractures

often caused by repeated low magnitude forces

March # - 2nd metatarsal

Jone's # - base of fifth metatarsal -

Stress Fractures Often found in runners

especially long distance runners

Females tend to be more susceptible than males

2nd and 3rd more commonly affected , but a stress fracture may develop any where

MOI : overuse , however it can be due to a traumatic event

s/s

Insidious onset of vague pain Tenderness to palpation Possible loss of function

Bone scan Decreased activity 4- 6 weeks Surgical fixation if necessary

Hallux Valgus

bunion - typically found on the medial aspect of the MTP joint of the great toe

on lateral side of foot they are called - bunionettes

pronation of the foot - arthritis, and generalized ligamentous laxity can lead to thickening on the medial side of the first MT head

as condition worsens , the great toe may shift laterally and overlap the second toe

this condition is exacerbated by high heels, pointed shoes - thus it is more common in women than men

once deformity has occurred little can be done

tapping in more anatomical position may help – or the use of a toe spacer - otherwise surgery is indicated in severe cases

Retrocalcaneal Bursitis pump bump external pressure from a heel cup excessive pronation poorly padded heel counter all these lead to swelling, redness of

the skin and irritation of the bursa (retrocalcaneal bursa located between the anterior Achilles’ tendon and calcaneus)

pain on palpation , active plantar flexion Rx - gentle stretching , shoe modification -

heel lifts pump bump - large bone spur commonly

seen in runners and skaters

Morton's Neuroma

plantar nerve becomes compressed between the MT heads

due to tight fitting shoes or pronated feet this leads to irritation of the nerve - pain Rx - larger shoes - arch supports (MT

pads) local injections

Blisters and Calluses

excessive localized pressure or friction between the skin and shoe

caused by shearing forces which cause fluid accumulation to separate the skin layers

fluid is usually clear - sometimes bloody

should be regularly shaved with a callous file or emory board

blood blisters may appear under calluses that are to large and become detached from the underlying skin

Calluses

Preventing Blisters

wear properly fitted shoes break shoes in gradually lubricants can be applied to susceptible

areas (petroleum jelly, skin lube)

Athlete's foot (tinea pedis) a common fungal infection can be spread

during casual handling of contaminated socks or picked up in a shower often based on an individual susceptibility and may not affect certain people

characterized by extreme itching, burning and irritation on the sole of the foot and between the toes

Rx with topical antifungal agents and proper foot care

Toe Sprains

tripping or stubbing pain , dysfunction, immediate swelling dislocation - obvious deformities strap with next toe for a week to two

weeks

Plantar Fasciitis excessive tightness of Achilles tendon, excessive

pronation , obesity predisposing factors - training errors, overuse ,

hyperpronation pain upon rising in morning - usually subsides with

in a short period of time but builds trough out the day

point tenderness over medial calcaneus - increases with forefoot dorsiflexion and toe extension

Rx - taping of arch - foot orthoses (heel spurs)

Ingrown toenail Preventable with proper care, hygiene

and nail care Toenail should be trimmed straight

across to prevent edges from growing under the skin on the side of the nail

Proper fitting shoes should be worn Problems with shoe size , improper care

of nails and sliding of foot in shoe may cause the edge to grow into the lateral nail fold and surrounding skin

The nail margin reddens and becomes very painful , may become infected

RX- soak the foot in hot (salty) water Lift the nail bed and place cotton under the nail

to elevate it from the skin fold Apply antiseptic over the area daily If infection occurs refer to doctor Also can try to soak the toe and then cut a V in

the centre of the nail As nail grows it pull the nail away from under the

skin again if infected refer to doctor