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Although the treatment results in pedi-atric foot trauma are generally good, potential pitfalls in the treatment of Lisfranc fractures, talar neck and body fractures, and lawn mower inj

Foot fractures account for 5% to 8%

of pediatric fractures and

approxi-mately 7% of all physeal injuries.1-4

These fractures are very rare in

infants and toddlers due to the

large cartilage component of their

feet (hence the relative resistance to

fracture), but the incidence increases

with age The more elastic and

pressible nature of cartilage in

com-parison to bone partly explains why

foot fractures are less common in

children than in adults As with most

traumatic injuries, pediatric foot

fractures occur more commonly in

boys than in girls

The child’s foot is generally a

for-giving location for fractures The

vast majority of pediatric foot

frac-tures do well with nonoperative

management There are, however, a

group of these fractures that may

have poor results even with

ana-tomic reduction and internal

fixa-tion A comprehensive

understand-ing of the anatomy of the foot,

espe-cially the location and nature of

injury to the physes, is requisite for optimal evaluation and treatment of children with these injuries

Anatomy

As with other musculoskeletal inju-ries, a thorough understanding of the relevant anatomy is crucial in the diagnosis and treatment of pe-diatric foot fractures The foot can

be thought of as consisting of three main subdivisions: the forefoot, the midfoot, and the hindfoot The forefoot consists of the metatarsals and phalanges The phalangeal physes are located proximally, but the metatarsal physes are located distally in all but the first meta-tarsal The forefoot is separated from the midfoot by the tarsometa-tarsal (Lisfranc) joint

The tarsometatarsal joints have tremendous intrinsic stability as a result of both the osseous architec-ture and the associated ligamentous

structures The recessed base of the second metatarsal locks between the medial and lateral cuneiforms, limiting medial-lateral translation

of the metatarsals Another ana-tomic consideration is the trape-zoidal shape of the middle three metatarsal bases, which form a

“Roman arch” configuration when they are positioned side by side, affording stability in the sagittal plane The metatarsals are held together by the transverse metatar-sal ligaments distally In addition, the bases of the lateral four metatar-sals are secured by the intermeta-tarsal ligaments There is no inter-metatarsal ligament between the first and second metatarsals, which can predispose to a medial Lisfranc injury The Lisfranc ligament, which extends from the medial cuneiform

to the base of the second metatarsal, further enhances the stability of these joints

Dr Kay is Professor of Orthopaedic Surgery, University of Southern California School of Medicine, Los Angeles, and Attending Surgeon, Childrens Hospital Los Angeles, Los Angeles, Calif Dr Tang is Resident, Department of Orthopaedic Surgery, University of Southern California, Los Angeles.

Reprint requests: Dr Kay, Childrens Hospital Los Angeles, 4650 Sunset Boulevard, Mailstop

69, Los Angeles, CA 90027.

Copyright 2001 by the American Academy of Orthopaedic Surgeons.

Abstract

Foot fractures account for 5% to 8% of all pediatric fractures and for

approxi-mately 7% of all physeal fractures A thorough understanding of the anatomy

of the child’s foot is of central importance when treating these injuries Due to

the difficulties that may be encountered in obtaining an accurate physical

exam-ination of a child with a foot injury and the complexities of radiographic

evalua-tion of the immature foot, a high index of suspicion for the presence of a fracture

facilitates early and accurate diagnosis Although the treatment results in

pedi-atric foot trauma are generally good, potential pitfalls in the treatment of

Lisfranc fractures, talar neck and body fractures, and lawn mower injuries to

the foot must be anticipated and avoided if possible.

J Am Acad Orthop Surg 2001;9:308-319 Evaluation and Treatment

Robert M Kay, MD, and Chris W Tang, MD

The Chopart transverse

mid-tarsal joint separates the midfoot

from the hindfoot (talus and

calca-neus) The talus is unusual in that

a large portion of its surface is

ar-ticular cartilage Articulations of

the talus include the talar body

with the tibial plafond proximally,

the inferior surface of the talus

with the calcaneal facets plantarly,

and the head of the talus with the

navicular distally

In contrast to the talus, the

calca-neus has numerous muscle and

tendon attachments There are

three articulating facets on the

superior surface of the calcaneus: a

large posterior facet, a concave

middle facet, and an anterior facet

Together, these form a complex

sub-talar joint with the corresponding

talar facets The anterior facet also

articulates with the cuboid The

Achilles tendon inserts on the

poste-rior tubercle

The lateral and medial plantar

processes serve as points of origin

for the plantar fascia and the small

muscles of the plantar surface of the

foot The plantar fascia has a thick

central fibrous tissue encased by

thinner lateral bands The fascia

spreads into five sections distally,

each travelling to a toe and

strad-dling the flexor tendons The

super-ficial layers are attached to the deep

skin fold between the toes and the

sole of the foot

There are nine compartments of

the foot: the medial and lateral

partments, the three central

com-partments, and the four interosseous

compartments.5 The medial

com-partment contains the abductor

hal-lucis and flexor halhal-lucis brevis

mus-cles as well as the tendon of the flexor

hallucis longus The lateral

com-partment contains the abductor digiti

minimi and flexor digiti minimi

muscles The three central

compart-ments contain the flexor digitorum

brevis and the four lumbrical

mus-cles, along with the tendons of the

flexor digitorum longus in the

su-perficial compartment, the adductor hallucis in the adductor compart-ment, and the quadratus plantae in the calcaneal compartment The cal-caneal compartment is limited to the hindfoot and is confluent with the deep posterior compartment of the leg Each interosseous compartment contains a plantar and a dorsal inter-osseous muscle

The timing of the appearance of the ossification centers in the pedi-atric foot is quite variable In young children, these ossification centers represent only a small portion of the bone, as a large cartilage anlage is present The calcaneus, cuboid, and talus are the tarsal bones that are most commonly ossified at the time

of birth, with the calcaneus begin-ning to ossify at around 5 months of gestation, the cuboid at 9 months, and the talus at 8 to 9 months The phalanges also start ossifying at 2 to

4 months of gestation The lateral cuneiform starts to ossify 1 year after birth; the medial and middle cunei-forms, at 4 years The secondary os-sification centers for the metatarsals and the phalanges ossify at around 3 years, as does the navicular The secondary ossification center for the calcaneus is the last to ossify, at 10 years

The presence of one or more of the various accessory ossicles may confound the radiographic diagnosis

of a fracture (Fig 1) The os vesa-lianum may be mistaken for a frac-ture of the base of the fifth meta-tarsal The os fibulare and os tibiale (located at the lateral border of the cuboid and the proximal medial aspect of the navicular, respectively) are each present in 10% of the popu-lation The os trigonum, located at the posterior lip of the talus, is pres-ent in approximately 13% of the population, and is commonly mis-taken for an avulsion fracture of the talus

The terminal branches of the anterior and posterior tibial arteries provide the blood supply to the

foot The anterior tibial artery con-tinues as the dorsalis pedis artery, supplies the greater part of the dor-sum of the foot, and provides anas-tomosis with the deep plantar arch and the arcuate artery (which later supplies the dorsal metatarsal ar-tery) The posterior tibial artery divides to become the lateral and medial plantar arteries, with the lateral artery being dominant The lateral plantar artery also forms the plantar arch, which then gives rise

to the plantar metatarsal arteries and common digital arteries The blood supply to the talus is limited, making it prone to osteo-necrosis after a talar neck fracture.6

The posterior tibial artery gives rise

to the artery to the tarsal canal that feeds the deltoid branches, which

in turn supply parts of the talar body The dorsalis pedis artery gives off multiple arterioles that penetrate the superior surface of the head and neck of the talus, as well as the artery of the sinus tarsi The artery to the tarsal canal and the artery of the sinus tarsi form an anastomotic arch that supplies most of the talus body by retro-grade fill In the child’s foot, there

is less dominance of a single

arteri-al system with retrograde flow from the neck, which may explain a potentially lower risk of osteone-crosis after talus fractures in chil-dren

The posterior tibial nerve gives rise to the medial and lateral plantar nerves The lateral plantar nerve innervates the intrinsic musculature

of the plantar aspect of the foot as well as the adductor hallucis The lateral plantar nerve also provides sensation to the lateral one and a half toes, analogous to the ulnar nerve distribution in the upper ex-tremity The medial plantar nerve supplies sensory branches to the medial three and a half toes, simi-lar to the sensory distribution of the median nerve in the upper ex-tremity

Although most pediatric foot

frac-tures are isolated injuries, some

occur in polytrauma patients,

war-ranting serial examinations In one

series, 21 (17%) of 125 patients with

pediatric ankle and foot injuries had

other skeletal injuries as well.7

Patients with massive soft-tissue

injury present special challenges A

careful neurovascular examination

is essential, but often difficult in a

frightened, uncooperative child

Palpation of pulses and assessment

of capillary refill are important

Doppler evaluation of a child with a

pulseless foot is often necessary

Noxious stimuli, including needle

sticks, can be used to help assess

sensation in the child who will not cooperate with evaluation of light touch sensation distal to the injury

As in adults, compartment syn-dromes may occur after crush or other high-energy injuries.8 Affected feet are quite swollen and generally very painful Compartment pres-sure meapres-surements are invaluable

in the assessment of a child with a suspected compartment syndrome, especially one who is obtunded and has significant swelling of a foot as-sociated with a fracture Fasciotomy should be performed if compart-ment pressures exceed 30 mm Hg

Anteroposterior (AP), lateral, and oblique radiographs are most com-monly utilized to assess patients with foot trauma The oblique

radio-graphs are necessary to supplement the AP and lateral views because of the significant osseous overlap on the lateral view Other specialized views and/or computed tomographic (CT) and magnetic resonance (MR) imag-ing studies may be necessary to com-pletely evaluate specific fracture con-figurations Comparison views are rarely necessary for the orthopaedist familiar with the normal radio-graphic appearance.9

Fractures and Dislocations

of the Talus

Fewer than 1% of all pediatric frac-tures and only 2% of all pediatric foot fractures are talus fractures.1,10

Os cuboideum secundarium, 1%

Os tibiale externum, 10%

Os tibiale externum, 10%

Os intercuneiforme

Os sustentaculum, 5%

Talus secundarius

Os trigonum, 13%

Calcaneus secundarius, 4%

Os intercuneiforme

Os intermetatarseum, 9%

Os vesalianum

Os peroneum

Pars fibularis ossis metatarsalis I

Os peroneum

Os vesalianum

A

Figure 1 Accessory ossifications in the foot and their frequency of occurrence (if data are available) (Adapted with permission from

Tachdjian MO [ed]: Pediatric Orthopedics, 2nd ed Philadelphia: WB Saunders, 1990, p 471.)

In a series of 90 pediatric talus

tures, there were 50 avulsion

frac-tures (56%), 18 osteochondral

le-sions (20%), 17 talar neck fractures

(19%), and 5 talar body fractures

(6%).11

Avulsion fractures require only

symptomatic treatment, often with a

short leg splint or short walking cast

for 1 to 2 weeks until symptoms

subside There are generally no

long-term sequelae

As in adults, talar neck and body

fractures result from forceful

dorsi-flexion of the ankle However, in

reported series dealing with

chil-dren, the mechanism of injury was a

fall from a height or a motor vehicle

accident in approximately 70% to

90% of cases.11,12 Of all talar neck

and body fractures, only 10% occur

in children.13 These fractures occur

throughout childhood and have

even been reported in children less

than 2 years old.11,12 Jensen et al11

reported that 6 (43%) of the 14

pa-tients in their series of pediatric talar

neck and body fractures had associ-ated fractures

Signs and symptoms of talar frac-tures include ankle or hindfoot pain, local tenderness, and pain with ankle dorsiflexion Local swelling is variable Plain radiographs fre-quently delineate the fracture line and the amount of displacement, al-though they may be read as normal initially.12 Computed tomography may aid in the assessment of frac-ture configuration and displace-ment

The Hawkins classification sys-tem is most commonly used for classifying talar neck fractures in children as well as in adults.14,15

Type I fractures are nondisplaced (Fig 2) Type II fractures are dis-placed talar neck fractures in con-junction with subluxation or dislo-cation of the subtalar joint Type III fractures are displaced talar neck fractures in conjunction with sub-luxation or dislocation of both the subtalar and the tibiotalar joint The

extremely rare type IV injuries are characterized by a displaced talar neck fracture, subluxation of the head of the talus from the talonavic-ular joint, and subluxation or dislo-cation of the subtalar and/or ankle joints

Osteonecrosis of the talar body is common after fractures of the talar neck and body due to disruption of the vascular ring surrounding the talar neck as the fracture displaces Because the surface of the talus is mostly articular cartilage, the talar blood supply is tenuous Overall, the risk of osteonecrosis in reported series of talar neck fractures that combine adult and pediatric patients

is approximately 50%, and is highest for type III and IV fractures and low-est for type I fractures In one such series, Canale and Kelly16reported osteonecrosis in 15% of type I frac-tures, 50% of type II fracfrac-tures, and 84% of type III fractures In another series, Jensen et al11reported no cases of osteonecrosis in 10 fractures

Figure 2 AP (A) and lateral (B) radiographs of a minimally displaced talar neck fracture (arrows) in a 4-year-old boy who sustained

ipsi-lateral fractures of the distal tibial physis and distal fibular diaphysis C, CT scan confirms minimal displacement Fracture comminution

is evident (Courtesy of J Dominic Femino, MD.)

(3 of which were displaced) Letts

and Gibeault12reported 3 cases of

osteonecrosis in 13 nondisplaced

pediatric talar neck fractures

(inci-dence of 23%)

The Hawkins sign (lucency in

the subchondral bone of the talar

dome, usually seen by 8 weeks

after injury) suggests that the talar

body is adequately vascularized

and the risk of osteonecrosis is low

Technetium bone scanning and,

more commonly, MR imaging can

be useful to assess the presence of

osteonecrosis in borderline cases

Treatment of nondisplaced talar

neck and body fractures consists of

immobilization in a

non-weight-bearing long leg cast After

approxi-mately 2 months, a patient with a

positive Hawkins sign (indicating

that there is no osteonecrosis) may

begin weight bearing as tolerated

A closed reduction should be

attempted for displaced talar

frac-tures, although the criteria for an

acceptable reduction have not been

clearly defined In general, however,

the surgeon should attempt to

achieve an intra-articular reduction

with less than 2 mm of residual

dis-placement These fractures are

of-ten stable with the foot in a

plantar-flexed position If open reduction

and internal fixation is performed,

insertion of screws into the talus

from posterior to anterior has been

shown to be biomechanically

supe-rior to insertion from antesupe-rior to

posterior.17

Long-term follow-up suggests

that pain is common after displaced

talar fractures in children.11 Whether

this pain is due to the initial

high-energy injury and associated

chon-dral damage or to residual

intra-articular incongruity is unclear.11

Follow-up radiographic studies have

demonstrated the development of

arthrosis in the ankle joints, but not

the subtalar joints, of patients with

displaced talar fractures.11

The duration of protected weight

bearing for patients with

osteone-crosis remains controversial Vari-ous mechanisms of unloading the talus have been tried, including the use of ambulatory aids, bracing, and casting Letts and Gibeault12

reported on three pediatric patients with osteonecrosis after talar neck fractures Talar flattening and ankle stiffness developed in two patients after bearing weight on the affected extremity (due to a delay in diagno-sis) The patient whose weight bear-ing was limited until the osteone-crotic segment had healed did not have such complications Even when weight bearing is not recom-mended, the long-term effect and the influence of patient compliance

on outcome are unclear

Peritalar dislocations are defined

as dislocations of the subtalar joint and talonavicular joint in the ab-sence of a talar fracture These inju-ries are rare, accounting for only 4%

of all pediatric talar fractures and dislocations.18 These are generally high-energy injuries and were asso-ciated with ipsilateral foot fractures

in all 5 patients in the series of Dimentberg and Rosman.18 Closed reduction is generally feasible, but may be impossible if diagnosis is delayed or if there are interposed soft-tissue or osseous structures

Osteochondritis Dissecans

of the Talus

The talus is the second most com-mon site for osteochondritis cans (OCD) Osteochondritis disse-cans of the talus is analogous to that found in other anatomic locations and is characterized by necrotic bone underlying articular cartilage

In the talus, OCD usually occurs either anterolaterally or posterome-dially

Children with OCD of the talus may present with the acute onset of pain after a traumatic incident (such

as an inversion injury) or with

chron-ic ankle pain Trauma to the ankle

has been reported in 46% to 63% of children with OCD of the talus.19,20

The mean age of children with OCD

of the talus is 13 to 14 years, al-though it may be seen in children less than 10 years old.19,20 Signs and symptoms in the affected ankle may include pain, swelling, instability, repetitive sprains, and decreased range of motion In one series,20the average duration of symptoms prior

to diagnosis was 4.3 months Locking

of the ankle joint is rarely reported Physical examination usually dem-onstrates decreased range of motion

of the ankle, which is often painful Localized tenderness may be difficult

to elicit, and the presence of synovitis

is variable

Grading of OCD of the talus is based on the system described by Berndt and Harty in 1959.21 Type I lesions are nondisplaced Type II lesions are partially detached Type III lesions are detached but not dis-placed Type IV lesions are detached and displaced or rotated Plain radio-graphs will often demonstrate a tri-angular sclerotic fragment separated from the talar dome anterolaterally

or posteromedially (Fig 3) Some-times, these lesions are hard to visu-alize on plain films, depending on their location in the sagittal plane Magnetic resonance imaging is the most helpful radiologic study for assessing OCD of the talus.22

This modality can help delineate the condition of the articular carti-lage, whether the articular cartilage

is intact, the extent of the lesion, the extent of sclerosis of the fragment, and whether the fragment is dis-placed Evidence of fluid under-neath the OCD fragment indicates disruption of the articular cartilage The MR study should be used in conjunction with plain radiographs

to classify these lesions

The course of OCD of the talus appears to be more benign in chil-dren than in adults Bauer et al23

reported on five children with OCD

of the talus followed up for an

aver-age of 22 years: four of the lesions

regressed, the fifth did not progress,

and no patient had radiographic

evidence of osteoarthritis at

long-term follow-up The results of

sur-gical treatment also appear to be

better in children than in adults.19,23

Nonoperative management has

been recommended as the initial

treatment of choice for all but type

IV lesions,19,20generally beginning

with immobilization and protected

weight bearing for 1 to 2 months

Activity modification and protected

weight bearing may continue for an

additional 2 to 3 months If there is

no symptomatic and radiographic

improvement by 3 to 4 months,

drilling, debridement, or

arthro-scopic fixation may be indicated

Greenspoon and Rosman24reported

that the results of bone grafting

were better than the results of OCD

fragment excision Arthrotomy

with a medial malleolar osteotomy

has been used in various series, but

often can be avoided owing to

ad-vances in arthroscopic technique

Type IV lesions should be treated operatively

Calcaneal Fractures

Approximately 5% of all patients with calcaneal fractures are chil-dren25; however, calcaneal fractures represent only 2% of pediatric foot injuries.10 Boys are more commonly affected than girls Extra-articular fractures are more frequent in chil-dren than in adults, representing 65% of pediatric calcaneal frac-tures.25,26 Fifty percent of pediatric calcaneal injuries that occur after falls result in intra-articular frac-tures In adolescents 15 years and older, the fracture patterns are com-parable to those seen in adults.25

The mechanism of most calcaneal fractures is axial loading, with the talus being driven into the calcaneus

The fracture is most commonly due

to a fall from a height or a motor vehicle accident (incidence rates of 40% and 15%, respectively, in two

studies25,26) Because these injuries generally are the result of high-energy trauma, associated injuries are com-mon, occurring in approximately one third of children with calcaneal fractures These may be lacerations

of the ipsilateral lower extremity25,26

or even spine fractures (5% of the children in one study25) In an early series before the advent of CT and

MR imaging, 26% of calcaneal frac-tures were missed initially.25

A plain-radiographic study should include AP, lateral, and axial views Oblique calcaneal views may also aid

in the initial assessment of fracture configuration The lateral view is im-portant because it allows measure-ment of the Böhler’s angle (Fig 4) Böhler’s angle normally measures 25

to 40 degrees in adults, but is less in children.14 The “crucial angle of Gisanne” is rarely measured in chil-dren because a large portion of the calcaneus is not yet ossified The angle usually measures 125 to 140 degrees in adolescents A CT scan may also be valuable in assessing the

Figure 3 AP (A) and lateral (B) radiographs of a 14-year-old boy with a 1-year history of ankle stiffness after an inversion ankle injury

demonstrate a large osteochondral lesion (arrows) of the anterolateral talar dome At the time of presentation, the patient was fully active

and denied pain C, CT scan demonstrates a type III lesion and significant sclerosis of the osteochondral fragment Observation was

undertaken because of the minimal symptoms.

configuration of an intra-articular

fracture

There are several classification

sys-tems for calcaneal fractures The

Essex-Lopresti method is widely

used This system categorizes injuries

as tongue-type or split-depression

fractures, but the most important

dif-ferentiation is between intra-articular

(Fig 5) and extra-articular fractures

Extra-articular fractures can be

treated with a bulky Jones dressing

followed by weight bearing in 3 to 4

weeks The long-term sequelae of

such fractures are rare, although

there may be some residual loss of

heel height and widening of the heel

Some authors advocate surgical

treatment for displaced intra-articular

fractures in young patients

How-ever, Schantz and Rasmussen27

reported good results in pediatric

patients treated nonoperatively

Thomas28reported good results even

in patients with a decreased Böhler’s

angle who were treated

nonopera-tively; these results were thought to

be secondary to potential talar

re-modeling in the pediatric population

Although the optimal treatment for

younger patients remains

controver-sial, open reduction and internal

fixa-tion is indicated for displaced intra-articular calcaneal fractures in adoles-cents, as it is in adults

Other Tarsal Fractures

Tarsal fractures account for approxi-mately 1% of all pediatric fractures.1

Fractures of the navicular, cuboid, and cuneiforms are reported to rep-resent 2% to 7% of pediatric foot injuries.10,29 Most tarsal fractures are avulsion or stress fractures, both

of which can be treated in a short walking cast for 2 to 3 weeks This

is sufficient to allow healing, and no long-term sequelae need be expected

Complete displaced fractures of the navicular, cuneiforms, and cu-boid often result from high-energy trauma; therefore, associated injuries, such as those of the Lisfranc com-plex, are common Because much of the surface of these bones is intra-articular, closed or open reduction and internal fixation may be needed for displaced fractures Assessment

of the soft-tissue envelope is impor-tant in these high-energy injuries, and compartment syndrome must

be ruled out

Lisfranc Injuries

Injuries of the tarsometatarsal joint complex are uncommon in children The mechanism of injury is either forceful plantar-flexion of the foot, generally with axial loading, or a direct crush injury Falls from a height accounted for approximately 60% of the pediatric Lisfranc inju-ries in the two largest seinju-ries.30,31 Of the 34 patients in those studies, 21 (62%) were boys The age range in the two studies differed consider-ably: Johnson30 reported that the fracture occurred most commonly

in children aged 3 to 6 years, but Wiley31reported a mean patient age

of 12 years Johnson reported frac-tures of the proximal first metatarsal

in all 16 of his patients, including 1 with a concomitant second metatar-sal fracture

Ligamentous injury may accom-pany fractures as the Lisfranc joint complex is loaded Because the plan-tar ligaments of the plan-tarsometaplan-tarsal joint complex are stronger than the dorsal ligaments, the dorsal liga-ments rupture first With continued

Figure 5 Lateral radiograph demonstrates

a minimally displaced intra-articular cal-caneal fracture (split-depression type) in a 4-year-old boy involved in a motor vehicle accident Associated injuries included an ipsilateral femoral shaft fracture, contralat-eral distal femoral physeal fracture, and a degloving injury to the contralateral leg Care for the calcaneal fracture consisted of initial splinting and a 3-week non-weight-bearing period The dotted lines indicate the fracture pattern.

Figure 4 Lateral view of the calcaneus depicts Bohler’s angle and Gissane’s angle.

Böhler’s angle is defined as the angle between two lines as seen on the lateral view: the

first connects the superior portion of the anterior and posterior calcaneal facets, and the

second connects the superior portions of the posterior facet and the tuberosity (Adapted

with permission from Heckman JD: Fractures and dislocations of the foot, in Rockwood

CA, Green DP, Bucholz RW, Heckman JD [eds]: Rockwood and Green’s Fractures in Adults,

4th ed Philadelphia: Raven Publishers, 1996, p 2326.)

Böhler’s angle

Lateral process

Navicular

Talus

Cuboid

Calcaneus

Crucial angle

of Gissane

loading, the plantar ligaments then

rupture, after which plantar

dis-placement of the metatarsal bases

may occur

Children who sustain Lisfranc

in-juries due to high-energy trauma

often have significant soft-tissue

injury and should be admitted to the

hospital for observation overnight

Compartment syndrome may be

her-alded by pain out of proportion to

the injury, as well as pain with

pas-sive motion of the toes in the awake

patient Compartment pressures

must be measured if there is the

pos-sibility of a compartment syndrome

in any patient, regardless of cognitive

status In patients with altered

men-tal status, the physician should be

more inclined to measure

compart-ment pressures, as clinical signs of

pain may not be easily appreciated in

the obtunded patient Fasciotomy of

all compartments of the foot should

be performed if compartment

pres-sures are greater than 30 mm Hg.5,8

Lisfranc injuries may involve the

entire tarsometatarsal complex or

any portion thereof Diastasis

fre-quently occurs between the bases of

the first and second metatarsals, as

there is no intermetatarsal ligament

in that interval (Fig 6)

Alterna-tively, all five rays may be involved,

either with all rays displacing in the

same direction (homolateral injury)

or with the first ray displacing

me-dially and the lateral four rays

dis-placing laterally (divergent injury).32

The initial radiographic

evalua-tion should consist of AP, oblique,

and lateral radiographs If possible,

the AP and lateral films should be

weight-bearing views, as subtle

injuries may not be evident on

non-weight-bearing radiographs.33

Frac-tures of the base of the first

meta-tarsal are common, but an isolated

fracture of the base of the second

metatarsal may result from avulsion

of the insertion of the Lisfranc

liga-ment, heralding the presence of an

injury to the Lisfranc complex If no

fracture is evident on presentation,

the medial aspect of the base of the second metatarsal should line up with the medial aspect of the mid-dle cuneiform, and the medial as-pect of the base of the fourth meta-tarsal should line up with the medial aspect of the cuboid

Nondisplaced fractures at the level of the tarsometatarsal joint complex may actually be injuries that were initially displaced but then spontaneously reduced Patients with such injuries may be treated with a bulky dressing or posterior plaster splint for several days to 1 week, followed by a non-weight-bearing short leg cast until 1 month after injury, and then a short walk-ing cast for an additional 2 weeks

Patients with Lisfranc fracture-dislocations should be treated opera-tively Closed reduction should be attempted in the operating room

Wiley31reported that 7 (39%) of 18 patients in his series required closed

reduction Finger traps placed on the toes facilitate reduction If closed reduction is possible, internal fixa-tion should be performed Kirschner wires may be used in young chil-dren Cannulated screws are pre-ferred for the older child with suffi-cient bone stock for screw fixation If

a nearly anatomic closed reduction is not possible, open reduction should

be performed, with removal of any impediments to reduction (frequently osteocartilaginous fracture frag-ments), followed by internal fixation The long-term results in children with Lisfranc injuries are uncertain Even with short-term follow-up, Wiley re-ported residual pain at the Lisfranc joint in 4 (22%) of his 18 patients

Metatarsal Fractures

Metatarsal physeal fractures repre-sent 1% to 2% of all physeal injuries

Figure 6 AP radiographs of both the uninjured left foot (A) and the injured right foot (B)

of a 6-year-old boy whose right foot had been run over by a car the previous day Diastasis is evident between the first and second rays proximally and distally in the right foot Although the medial column is disrupted, the remainder of the Lisfranc complex is appropriately aligned The patient underwent open reduction and pinning after an unsuc-cessful attempt at closed reduction in the operating room.

in children and adolescents.1-3 In

one large series, metatarsal fractures

accounted for approximately 60% of

pediatric foot fractures, with

frac-tures of the base of the fifth

metatar-sal accounting for 22%.10 Owen et

al29 reported that first-metatarsal

fractures accounted for 73% of all

tarsal and metatarsal fractures in

children younger than 5 years, but

only 12% of such fractures in

chil-dren older than 5 In the same

se-ries, 6.5% of all fractures and 20% of

all first-metatarsal fractures were

initially unrecognized by the

treat-ing physician

The mechanism of metatarsal

frac-ture may be either indirect or direct

Indirect injuries often result from

axial loading, inversion, rotation, or a

combination thereof (Fig 7) Direct

injuries often result from the impact

of falling objects or crush injuries If

these fractures occur proximally

rather than in the midshaft, evalua-tion of the tarsometatarsal joint com-plex for concomitant injury is impor-tant Radiographs should consist

of AP, lateral, and oblique views to assess fracture alignment Medial-lateral displacement of the fracture may be seen, but is acceptable in the absence of displacement of the Lis-franc complex

If these fractures are not proxi-mal, they can almost always be treated with weight bearing as toler-ated in a short walking cast or a cast shoe The duration of treatment is generally 3 weeks (until tenderness

at the fracture site has subsided) In children with marked swelling, a circumferential cast should not be applied at the time of evaluation, and consideration should be given

to admitting the child for overnight observation Compartment syn-dromes, though rare, may occur if high-energy trauma has caused mul-tiple metatarsal fractures

In the rare instance in which there is marked sagittal malalign-ment of the metatarsal heads, closed reduction and pinning of a metatar-sal fracture should be considered to avoid transfer lesions in the future

Finger traps are often helpful in re-ducing such fractures

Growth disturbance may occur

as a result of a metatarsal fracture

Physeal fractures of the base of the first metatarsal may potentially cause a growth disturbance and shortening of the first ray This com-plication is rare, but may result in transfer lesions Overgrowth may also occur after metatarsal fractures

Fractures of the Base of the Fifth Metatarsal

Approximately 40% of all metatar-sal fractures are fractures of the base of the fifth metatarsal In one large series,10 as many as 22% of pediatric foot fractures were at that site In that same series, 90% of

fifth-metatarsal fractures occurred

in children older than 10 years As

in adults, the location of the frac-ture, the fracture appearance, and the duration of symptoms before presentation are important prog-nostic factors The injury generally occurs with the foot in a weight-bearing position Inversion has been reported as the most common mechanism of injury.29

The initial radiographic examina-tion should consist of AP, lateral, and oblique views The location of the fracture is important to both prognosis and treatment Tuber-osity fractures are generally benign and heal with 6 weeks in a short walking cast Although previously thought to be due to avulsion at the insertion of the peroneus brevis, tuberosity fractures now appear to

be due to avulsion at the origin of the abductor digiti minimi Frac-tures at or distal to the metaphyseal-diaphyseal junction are more recal-citrant to treatment These fractures should be treated with at least 6 weeks in a non-weight-bearing cast

If the fracture is preceded by weeks

to months of pain (or if there is radio-graphic evidence of a preceding stress injury), internal fixation should

be considered Some authors advo-cate curettage and bone grafting in patients with intramedullary sclero-sis indicative of a delayed union or nonunion.34,35

Phalangeal Fractures

Phalangeal fractures are common

in the pediatric population and of-ten do not even result in the child being seen by an orthopaedic sur-geon Many of these fractures are treated symptomatically by the pa-tient and family or by the primary-care physician Phalangeal fractures may account for as many as 18% of pediatric foot fractures.10 In three studies,1-3phalangeal fractures rep-resented 3% to 7% of all physeal

Figure 7 Displaced third- and

fourth-metatarsal fractures and a nondisplaced

second-metatarsal fracture sustained by a

15-year-old boy due to an indirect

mecha-nism of injury The patient was treated in a

short walking cast for 2 weeks, followed by

a cast boot for 2 additional weeks.

fractures and were usually

Salter-Harris type I or type II injuries

The examining physician must

closely evaluate the toe for integrity

of the skin and also make sure that

there is not a nail-bed injury Open

fractures require irrigation and

debridement and intravenous

anti-biotic therapy (Fig 8) Nail-bed

in-juries involving the germinal matrix

should be repaired

Closed fractures rarely require

reduction Buddy-taping of the toes

with weight bearing as tolerated

almost universally results in a

well-healed and well-aligned fracture

within 3 to 4 weeks (A hard-soled

shoe may be used for patient comfort

until fracture healing has occurred.)

Closed versus open reduction and

pinning should be considered for

markedly angulated fractures or

dis-placed intra-articular fractures of the

proximal phalanx of the great toe

(including Salter-Harris type III and

type IV fractures) involving more

than 25% of the joint surface and

those with more than 2 mm of

dis-placement

Growth arrest and stiffness are

uncommon sequelae of phalangeal

fractures When growth arrest

oc-curs, it most commonly follows

fractures of the great toe

Lawn Mower Injuries

Lawn mowers have been reported

to cause as many as 160,000 injuries

annually, including approximately

2,000 that result in permanent

im-pairment in children.36-38 Accidents

occur with all types of mowers, but

the most severe injuries usually

occur when young children are

struck by riding mowers In fact, as

many as 72% of children who

sus-tain severe lawn mower injuries are

bystanders.37,38

A careful evaluation of the entire

child, including all extremities, is

vital In a study of 33 children with

lawn mower injuries, Alonso and

Sanchez36 found that 8 (24%) had head and eye injuries, 12 (36%) had upper-extremity injuries, and 13 (39%) had lower-extremity injuries

Fractures must be evaluated in conjunction with the degree of soft-tissue damage and the integrity of neurovascular structures

These are high-energy injuries that frequently involve significant soft-tissue and fracture contamina-tion Initial treatment should consist

of irrigation and debridement and triple-antibiotic coverage Internal fixation of fractures and/or external fixation spanning the injured seg-ment may help stabilize the soft tis-sues, allow access to the zone of injury, and facilitate patient care

Repeat debridements should be per-formed at 2- to 3-day intervals until the wound is sufficiently clean

Soft-tissue damage from lawn mower injuries is extensive, and the soft-tissue envelope generally ap-pears better on presentation than it does in the ensuing days due to the initial compromised soft-tissue per-fusion Early involvement of the plastic surgery team is important to facilitate coverage of these wounds

by 7 to 14 days after injury Skin grafting or flap coverage is needed

in more than 50% of patients.37 Un-like adults, children may do well with split-thickness skin grafts placed on the plantar aspect of the foot.38 Despite appropriate early care, amputation rates in children with lower-extremity lawn mower injuries have ranged from 16% to 78%.36-38 Even in salvaged extremi-ties, late deformity may occur due

to muscle imbalance resulting from the damage or loss of muscles, ten-dons, or nerves at the time of injury

Occult Foot Fractures

Toddlers often present with the acute onset of a limp but without a definite trauma history Unlike a

“toddler’s fracture,” there may be no tenderness over the tibia Tender-ness is often evident in the foot, but may be hard to pinpoint Typically,

a child with an occult foot fracture will be able to crawl without diffi-culty but will limp when walking Plain radiographs will rarely reveal a fracture A bone scan,

how-Figure 8 AP (left) and lateral (above) radiographs of a

12-year-old boy after an open Salter-Harris type II fracture of the distal phalanx of the great toe The open fracture was not recognized on initial presentation When the patient presented to the author’s institution, purulent drainage and cellulitis were evident Treatment consisted of irrigation and debridement, followed by open reduction and percuta-neous pinning of the fracture (Courtesy of Richard A K Reynolds, MD, Los Angeles, Calif.)