Proximal Radius

(1)

695

Proximal Radius

For purposes of definition, radial head fractures in children are those that include the physis, or if in old- er children whose physes are closed include the ar- ticular surface. Radial neck fractures are metaphyseal, entirely distal to the physis [14]. Physeal fracture types 1, 2, 5, and 6 also involve the metaphysis, but since the major problem is physeal involvement they all qualify as fractures of the head.

Contents

Anatomy and Growth .. . . ..695 Classification ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 696 Epidemiology .. . . 696 Literature.Review. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 696 Head.and.Neck... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 696 Head.. . . .698 Olmsted.County.Study. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .698 Evaluation . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .699 Management ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . .700 Type.1... . . .704 Types.2.and.3. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. .704 Type.4... . . ..709 Type.5... . . ..713 Type.6... . . ..717 Excision.of.the.Radial.Head.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .718 Complications . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .718 Physeal.Arrest. .. . . ..727 Enlargement.of.the.Radial.Head. ... .. .. .. .. .. .. .. .. .. .. ...727 Loss.of.Motion. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .727 Delayed.Union.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .727 Malunion. ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...727 Nonunion. .. . . ..729 Heterotopic.Bone. ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...729 Ischemic.Necrosis.... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...729 Synostosis... . . ..729 Irreducible.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .731 Neuropathy.... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...731 Compartment.Syndrome.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .731 References . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .731

Chapter 21

Anatomy and Growth

Even in the embryo the head and neck of the radius are well defined, and have the same shape and relative size as an adult [16, 21]. Prior to the appearance of the epiphyseal secondary center of ossification (SCO), the same concave articulating surface of the head, much larger than the neck, should be conceptually “visual- ized” on toddlers’ roentgenographs. The center of this epiphysis begins to ossify at about the age of 4 years in females and a year later in males [31]. Although the SCO may appear first as a sphere, ossification soon advances into one or two ovoid, flat, or wedge-shaped nuclei, which may be eccentrically located on the ra- dial metaphysis and misinterpreted as a fracture of the epiphysis. Notches and clefts in the proximal ra- dial metaphysis may closely resemble post-traumatic appearances [16, 37].

The epiphysis of the radial head is completely cov- ered by articular cartilage and fits over the metaphy- sis like a bottle cap (Fig. 15.7n). The mature radial head is cylindrical in shape, broad in its longitudinal length medially where it articulates with the ulna, and narrow in the rest of its circumference where it is surrounded by the annular ligament [16, 20]. The joint capsule, in continuity with the annular ligament, is attached to the metaphysis making the entire head intracapsular.

The cartilage of the head is nourished by synovial fluid [47]. The blood supply to the epiphysis is derived from small branches from the recurrent radial and superior interosseous arteries, which anastomose with the periosteal network of arterioles from the su- pinator muscle to course along the surface of the me- taphysis intra-articularly before penetrating the head.

This creates an intracapsular epiphyseal blood supply similar to that of the capital femoral epiphysis [47].

Thus, following fracture any remnant of periosteum attached to the head should be carefully preserved.

The proximal radial physis accounts for 20% of

growth of the mature radius (Fig. 21.1). The percent-

(2)

696 Chapter 21 Proximal Radius

age of growth provided by the proximal radial physis gradually diminishes throughout growth (Fig. 21.2).

Knowledge of the amount of growth remaining of the proximal radial physis (Fig. 21.3) is helpful when evaluating length related problems of the radius. Be- cause of this limited growth, problems related to lack of growth of the proximal radius are rare and usually of minor magnitude. The physis closes at age 12–

14 years in females and 14–15 years in males [42].

Classification

The six type anatomic classification works well here (Fig. 21.4) [26]. Classification based on degree of angulation [21] does not determine the amount of physeal damage, and is subject to the plane of the roentgenograph projection. In addition, the degree of angulation in a fresh fracture may change at any time before or after the original roentgenograph. No Salt- er-Harris compression type 5 injuries have been re- ported at this site.

Epidemiology Literature Review Head and Neck

The majority of articles in the literature either do not define distinctions between head and neck fractures, or mix the two together in ways which obviate ex- tracting epidemiologic data for either [4, 7, 9–11, 13, 15, 19, 32, 33, 35, 36, 39, 43]. Numerous articles con- cerning radial neck fractures in children are not in- cluded in this review, even though some radial head

É Fig. 21.1

Percentage.of.growth.at.birth,.mid-childhood,.and.at.

maturity . (Adapted. from. Pritchett. [30],. with. permission)

Fig. 21.2

The. percentage. contribution.

of. the. proximal. physis. to. the.

growth.of.the.radius.is.shown.

below.the.solid line.and.that.of.

the. distal. growth. plate. above.

the.line .The.vertical axis.shows.

the.relative.activity.of.the.proximal. and. distal. growth. plates . Line B.indicates.birth .The.solid.

line.is.extrapolated.back.to.the.

beginning.of.growth .(Redrawn.

from. Pritchett. [29,. 30],. with.

permission)

(3)

697 Proximal Radius Chapter 21

fractures may have been included in some of those articles.

The incidence of radial head and neck fractures combined has been estimated at 0.07 [9] to 0.19 [13]

per 100,000 children, ages 0–15 years per year. Of all pediatric elbow fractures, radial head and neck frac- tures represent 4–16% [14, 44]. Of these, approximate- ly 50% involve the head and 50% the neck [11, 14–16, 19, 33, 36, 43]. In 2000, Leung and Peterson [14] docu- mented 116 radial head and neck fractures in children

0 through 16 years (Table 21.1). There were 58 head and 58 neck fractures. Eighty-three involved an open physis: 42 in the metaphysis (neck), and in 41 the phy- sis (head).

There are notable exceptions to this 50-50 propor- tion. In Henriksson’s [9] series, 50 cases (91%) in- volved the neck, and 5 cases (9%) involved the head.

Landin and Danielsson [13] noted identical results: 86 cases (91%) in the neck and 9 cases (9%) in the head.

Tibone and Stoltz [42] had 24 cases (77%) in the neck

Fig. 21.3

Growth.remaining.in.the.proximal.radius.from.age.7.years.to.

maturity .(Redrawn.from.Pritch- ett.[28],.with.permission)

Fig. 21.4

Peterson. classification. of. proximal. radius.

fractures.in.children .M.Metaphyseal.(neck).

fracture . Fracture. types.1. through. 6,. all. of.

which. involve. the. physis,. are. fractures. of.

the.head .(Redrawn.from.Leung.and.Peter- son.[14],.with.permission)

(4)

and 7 cases (23%) in the head. Conversely, D’Souza et al. [4] had 17 cases (18%) in the neck and 79 cases (82%) in the head. This disparity may be best ex- plained by the lack of definition of a head versus a neck fracture, the difficulty in differentiating a head from a neck fracture, and by a possible difference in age of the populations studied, since head fractures are more common in older children (and adults) and neck fractures more common in younger children.

The mean age for radial neck fractures in children is 9.3–9.8 years, versus 12.6–14 years for radial head fractures [9, 13].

Head

The percentage of physeal fractures of the proximal radius is low compared with physeal fractures at all sites. From 1915 to 1970, 4% of all physeal fractures were in the proximal radius (Table 4.5). From 1970 to 1990, the percentage was 2% (Table 4.6). When con- sidering physeal fractures only of the radius, 6% are

proximal and 94% are distal (Table 4.7). When ana- lyzing physeal fractures of only the elbow, 23% were in the proximal radius (54 of 227 cases by Havránek and Hájková [8], Table 15.3).

Type 2 fracture was the most common (81%) prior to 1999 (Table 21.2). Of the 41 physeal fractures in the Leung and Peterson series in 2000 [14], 25 (61%) were Peterson type 1, and only 9 (22%) were type 2 (Ta- ble 21.3). This is the first analysis of any site using the Peterson classification and supports the speculation that type 1 fracture (Chapter 3A) is the most common physeal fracture. Since type 1 fracture involves both metaphysis and physis, it could easily be mistaken for a neck fracture or a type 2 physeal fracture and helps explain the predominance of type 2 physeal fractures [19, 33, 42], prior to recognition of the type 1 fracture in 1994 [25].

Fractures of the head which involve the articular surface (types 4, 5, and 6) are extremely rare in chil- dren with an open physis [3, 14, 20, 42]. In a review of the English literature, Leung and Peterson [14]

found only 15 cases prior to 2000. The outcome was recorded in only 2 cases. This study [14] added 6 more cases and also confirmed that articular fracture of the radial head is less common when the physis is open than when closed, and that the prognosis is ex- tremely poor for these younger children with articu- lar involvement.

Olmsted County Study

In this ten-year population-based study of physeal fractures at all sites, 6 of 951 (0.6%) were in the proxi- mal radius (Table 4.12) [27]. These 6 cases in the prox- imal physis comprised 3% of all radial physeal frac- tures, compared with 170 cases (97%) located in the distal radial physis (Table 4.13). There were 3 males,

Table 21.1. Fractures of the proximal radial neck and head in children.^a (Adapted from Leung and Peterson [14], with permission)

Radial neck

(metaphysis) Radial head (physis) Total

n (%) n (%) n (%)

Open physis 42 (36) 41 (35) 83 (71)

Closed physis 16 (14) 17^b (15) 33 (29)

ToTal 58 (50) 58 (50) 116 (100)

a One hundred and sixteen fractures, 0 through 16 years

b All 17 head fractures with closed physes involved the articular surface and were, therefore, similar to type 4 and 5 physeal fractures

Table 21.2. Proximal radius physeal fractures by type (Salter-Harris classification)

Year Author 1 2 3 4 5 Total

1987 Mizuta et al. [17] 3 13 0 0 0 16

Percent 18.1 81.2 0 0 0 100

Table 21.3. Proximal radius physeal fractures by type (Peterson classification) [26]

Year Author Type Total

1 2 3 4 5 6

2000 Leung [14] 25 9 1 1 4 1 41

Percent 61.0 22.0 2.4 2.4 9.8 2.4 100

(5)

ages 9, 10, and 11 years, and 3 females, ages 6, 6, and 11 years. There were one type 1, three type 2, one type 3, and one type 4 fractures (Table 4.12). The type 1 fracture was not known at the time of data col- lection and neck fractures were not reviewed. Un- doubtedly, many type 1 fractures were unknowingly overlooked.

Evaluation

Reluctance to move the elbow, swelling, and tender- ness of the proximal radius are present in both head and neck fractures. Crepitus is frequently absent.

Usually, altered alignment of the fragments can be neither clinically visualized nor palpated. Active or passive forearm rotation, particularly supination, is more painful than elbow flexion and extension.

Physeal fractures of the proximal radius are often associated with other elbow injuries: elbow disloca- tion, and fractures of the olecranon, ulnar diaphysis, humeral lateral condyle, and medial and lateral epi- condyle [5, 7, 33, 35, 36, 42]. Each of these fractures deserves individual evaluation and treatment.

Roentgenographic evaluation is crucial in making the diagnosis. True AP and lateral roentgenographs with proper density definition of bone, fluid, and soft tissue are essential. If the initial films are of marginal quality they should be repeated and supplemented with oblique views. A line drawn longitudinally through the radius transects the center of the normal lateral humeral epiphysis in all planes of elbow flex- ion and extension and forearm rotation. Since the en- tire radial head is intracapsular, fracture of the radial head usually produces elbow effusion and a positive fat pad sign. Elevation of a fat pad may be the only indication of an undisplaced radial head fracture [16].

Much of the radial neck lies distal to the capsule, causing some fractures of the radial neck to have no joint effusion or positive fat pad sign [37].

The normal valgus carrying angle of the elbow makes valgus injury more likely. A fall on the out- stretched hand with the elbow in extension, drives the capitellum against the outer side of the head of the radius, tilting it and displacing it laterally. The radial fracture may, therefore involve either the head or the neck. A second mechanism is posterior dislocation of the ulna with simultaneous compression of the capi-

tellum on the anterior portion of the head of the ra- dius [21]. This has the potential to produce the more serious type 4 and 5 fractures. Or, as the anterior dis- located capitellum is reduced, the epiphysis may be disloged posteriorly (type 3 fracture) [10].

Differentiating fractures that involve the physis (head) from those that involve only the metaphysis (neck) can be difficult (Fig. 21.5) [13, 15]. Since many injured children are unable to fully extend the elbow, the AP and oblique views are often made with the hu- merus and forearm in varying degrees of flexion. The x-ray beam then passes obliquely through the head which may conceal a physeal fracture or cause misin- terpretation (Fig. 21.6a) [20]. If so, true AP, lateral, and oblique roentgenographs should be made of the proximal radius with the patient sitting, the elbow flexed, and the forearm flat against a horizontal cassette. Sometimes the physeal portion of the frac- ture is determined only by visualization at the time of open reduction (Fig. 21.6b). In some cases the differ- entiation is only apparent weeks after the fracture (Fig. 21.7). This is a large part of the reason head and neck fractures are usually discussed together.

Magnetic resonance imaging has been little used in the proximal radius and is helpful in differentiat- ing unossified portions of physeal fractures. Obvi- ously it would be of most help if the MRI equipment is in the emergency room.

The type 1 fracture (Fig. 21.4) may be difficult to

diagnose and is very common (Table 21.3) [14]. It is

often incorrectly called a neck fracture or type 2 frac-

ture (Fig. 21.8a). Silberstein et al. [37] published a

typical type 1 fracture (their Fig. 10A), which at the

time was designated a type 2. The type 1 is distin-

guished by a transmetaphyseal fracture that extends

proximally to the physis. Sometimes the transme-

taphyseal portion of the fracture is only compression

of the metaphysis which may not be visible on the ini-

tial roentgenograms. A small metaphyseal “corner

sign” fragment is often present if the appropriate rota-

tional view is obtained. There is no fracture across the

main portion of the physis and the epiphysis is not

displaced on the metaphysis. Therefore, this is not a

type 2 fracture. When an overt transmetaphyseal

fracture has a fracture line extending to the physis it

is often best seen on oblique views. Transmetaphyseal

sclerosis is always present 3–6 weeks post fracture

and verifies the compression component (Fig. 21.8b).

(6)

Management

Treatment considerations of proximal radial physeal fractures are based more on the amount of fragment displacement and the precise physeal damage, than on the degree of radial head angulation as espoused by some [2], or than by the fear of ischemic necrosis.

Of 16 fractures of the proximal radial physis in one series [17], 12 were treated with no reduction, 4 by

closed reduction, and none by open reduction. The use of biodegradable pins [5, 40] (Chapter 6), needs more evaluation. A fibrin adhesive system [1] was suc- cessfully used in a radial head fracture in a 16-year- old girl (presumably with a closed physis). Radial head prosthetic replacement for physeal fracture has had limited trial in children. It might be considered for the treatment of synostosis following physeal fracture of the head [45].

Fig. 21.5

Proximal.radius.type.2.fracture .This.11.year.4.month.old.boy.fell.one.foot.landing.on.his.outstretched.right.forearm ..

a. There. is. a. posterior. lateral. metaphyseal. fragment. (Holland. sign). attached. to. the. epiphysis. (arrows) . The. fracture.

.extends.proximally.along.the.physis.medially.and.anteriorly .The.epiphysis.and.metaphysis.are.displaced.posteriorly.

on.the.lateral.view .Oblique.roentgenographs.may.have.enhanced.the.diagnosis .b.Three.months.later.the.fracture.is.

healed .There.is.no.transmetaphyseal.sclerosis.suggestive.of.a.neck.or.type.1.fracture

(7)

Fig. 21.6

Proximal.radius,.type.2.fracture .This.7.year.6.month.old.girl.fell.from.a.bicycle.injuring.her.left.elbow .a.An.oblique.view.

shows.a.displaced.tilted.radial.head .The.attempted.AP.view.was.obscured.by.inability.to.extend.the.elbow,.and.a.true.

lateral.was.not.taken.because.the.posterior.dislocation.of.the.ulna.prevented.elbow.flexion .Fracture.type.undeter- mined .Closed.reduction.was.unsuccessful .b.At.open.reduction.there.was.a.large.metaphyseal.fragment.attached.to.

the.head,.but.with.physis.exposed.posteriorly,.confirming.a.type.2.fracture .The.head.was.replaced.and.was.stable.in.

all.planes.of.flexion.and.rotation .A.large.bulky.bandage.(Jones).was.applied .c.Four.days.post.operation.there.is.mild.

anterior-lateral.displacement .A.long.arm.cast.was.applied.and.removed.at.six.weeks .Full.flexion,.extension,.and.forearm.rotation.was.present.at.8.weeks .(Continuation see next page)

(8)

Fig. 21.6 (continued)

d.One.year.post.fracture,.age.8.years.6.months.there.is.normal.ROM,.function,.and.a.15º.carrying.angle.bilaterally ..

The.patient.easily.does.pushups .Radial.neck.remodeling.is.complete.and.the.physis.is.normal .Note:.In.the.absence.of.

direct.visualization.at.the.time.of.open.reduction,.this.fracture.would.have.been.coded.a.neck.fracture,.rather.than.a.

physeal.fracture .This.phenomenon.occurs.because.the.large.cartilaginous.head.fits.on.top.of.the.relatively.smaller.

osseous.metaphysis

Fig. 21.7

Proximal.radius.type.2.fracture .This.6.year.10.month.old.girl.jumped.from.a.swing.landing.on.her.left.arm .a.The.radial.

head.and.part.of.the.metaphysis.are.displaced .Growth.plate.involvement.is.indeterminate .b.Closed.reduction.under.

general.anesthesia.and.application.of.long.arm.cast.shows.acceptable.position.and.alignment.of.the.fractured.fragment .Differentiation.between.a.radial.neck.or.a.radial.head.fracture.is.still.not.possible .The.cast.was.removed.4.weeks.

post.injury .c.Nine.weeks.post.fracture.the.patient.was.using.her.arm.normally.and.had.regained.all.but.10º.elbow.extension,.30º.flexion,.and.5º.pronation .The.roentgenographs.now.reveal.residual.mild.anterior.displacement.of.the.

epiphysis.on.the.metaphysis.with.an.attached.metaphyseal.fragment.and.new.subperiosteal.bone.on.the.side.of.the.

metaphyseal.fragment,.verifying.a.type.2.fracture .d.Six.months.post.fracture.elbow.flexion.was.R.–5/145º,.L.0/125º.

with.normal.pronation.(left).and.supination.(right) .(Continuation see next page)

(9)

(10)

Type 1

Type 1 fractures of the proximal radius (Fig. 21.4) are often subtle and are typically neither angulated nor displaced (Fig. 21.8). They may be immobilized for 2–3 weeks to avoid further injury and possible angu- lation. They invariably heal without sequelae.

Types 2 and 3

The metaphyseal fragment (Holland sign) of a type 2 fracture is often small, making it very similar to a type 3 fracture (Fig. 21.4). If a type 2 or 3 fracture is minimally displaced or can be manually reduced, immobilization for 3–4 weeks will suffice (Fig. 21.5).

e.At.age.8.years.0.months,.14.months.post.fracture,.all.elbow.motions.were.symmetrically.equal .The.fracture.has.re- modeled.nicely

Fig. 21.8

Proximal.radius.type.1.fracture .This.11.year.6.month.old.girl.injured.her.left.elbow.in.a.fall.down.stairs .a.AP,.lateral,.and.

oblique.roentgenographs.(left to right).show.a.fragment.of.bone.in.the.anterolateral.metaphysis.(arrow) .The.metaphysis.is.wider.than.normal,.yet.the.epiphysis.is.not.displaced.on.the.metaphysis,.and.the.physis.appears.normal,.except.

for.mild.widening.at.the.site.of.the.metaphyseal.fragment .There.is.a.thin.band.of.mild.sclerosis.in.the.radial.neck,.sug- gesting.impaction .A.posterior.splint.was.applied.followed.later.by.a.cast .(Continuation see next page)

(11)

A wire, pin, or hook inserted percutaneously can be used to manipulate a mildly or moderately displaced head into position [8, 38]. A type 2 or 3 fracture that heals in a displaced position may result in a cam effect with forearm rotation leading to degenerative arthro- sis. Multiple articles debate the degree of angulation of the radial articular surface that can be accepted and still expect a good outcome. This is well summarized by Rodriguez-Merchan [33]. Interestingly, specific numbers of degree are often given with no regard to positioning the forearm rotation to capture the great- est degree of angulation, or to the age of the patient.

Obviously, remodeling is limited in older children whose physes are near closure. In addition, many of these articles concern both head and neck fractures.

Remodeling of angulation is superior in neck frac- tures. No angulation or displacement of radial head fractures should be accepted.

When closed reduction is incomplete or unstable, open reduction is indicated. A posterolateral Kocher approach between the anconeus and extensor carpi

ulnaris is optimal. The capsule and annular ligament are divided to allow gentle reduction. Meticulous dissection helps preserve periosteum attachments and therefore the blood supply to the metaphyseal fragment of type 2 and 5 fractures [4]. Once reduced many of these fractures, particularly type 3, will then be stable and no internal fixation will be needed (Figs. 21.6, 21.9) [8, 12, 18, 22, 44]. The capsular and annular ligament repair are accomplished during closure.

Often the entire epiphysis of a type 3 fracture will be displaced through the joint capsule, and closed re- duction is not possible. Occasionally the epiphysis of a type 3 fracture will be found in excellent position, but reversed with the articular surface in apposition with the metaphysis [38, 46]. Some of the “head” frac- tures in which the epiphysis is rotated 180° reported in the literature were found at operation to be neck rather than head fractures, with metaphyseal bone consisting of one surface of the fragment. The roent- genographs of these cases need close review and the reduction requires surgical intervention.

b.Three.weeks.post.fracture.at.time.of.cast.removal.there.is.radial.neck.(metaphyseal).sclerosis.(arrows).confirming.

type.1.fracture,.and.early.subperiosteal.new.bone.formation.along.the.lateral.border.of.the.neck .c.Three.months.post.

fracture,.age.11.years.9.months,.the.patient.is.normally.active.and.asymptomatic .There.was.full.range.of.motion.and.

no.tenderness .The.fracture.is.healed,.the.epiphysis.and.physis.are.normal,.and.there.is.mature.subperiosteal.new.bone.

along.the.neck .(From.Leung.and.Peterson.[14],.with.permission)

(12)

Fig. 21.9

(13)

If the surgical reduction is unstable, internal fixa- tion with two crossed Kirschner wires or one longitu- dinal wire through the capitellum across the radio- carpal joint and into the intramedullary cavity of the radial diaphysis can be considered [8, 15, 22]. Retro- grade pinning by introducing wires in the radial me- taphysis and across the fracture site into the head, thereby not crossing the joint, is difficult to accom- plish without further displacing the epiphyseal frag- ment.

Transarticular pinning through the capitellum, ra- dial head, and into the radial diaphysis is hotly de- bated. Some surgeons use such pins routinely, others say “never” [2]. It is true that a small single wire will break at the joint level, even when supported by a long arm cast (Fig. 21.10) [24]. When this occurs and as long as fracture reduction is maintained, it is only necessary to remove the proximal portion of the bro- ken wire. If the proximal portion of the wire is exiting the skin this can be done easily at the time of cast

change or removal. With experience the surgeon learns to avoid this occurrence by using a sufficiently large wire. The wire should be perpendicular to, and in the center of, the physis. No physeal bars have been reported with the use of these wires. The wires may be removed in 3 weeks and gentle protected motion using a collar and cuff begun.

Alternative methods of treatment such as obliquely inserted Kirschner wires cut off intra-articularly [44]

or bone graft transplant to correct severe angulation might be considered in difficult cases.

Each method of internal fixation should be supple- mented with a long arm cast. Immobilization for 2–3 weeks, with the elbow in 90 degrees of flexion and the forearm in neutral rotation, is usually satis- factory. A collar and cuff supplementing the cast re- duces humeral rotation on the forearm and elbow motion within the cast. Sometimes stability is supe- rior with the elbow in extension [35].

Fig. 21.9

Proximal.radius.type.3.fracture .This.6.year.9.month.old.girl.injured.her.right.elbow .a.On.the.lateral.view.(right).the.radial.head.is.obscured.by.its.posterior.and.lateral.displaced.position .Two.attempts.at.reduction.by.manual.traction.and.

manipulation.under.general.anesthesia.were.unsuccessful .b.Left.elbow.for.comparison .c.Open.reduction.revealed.a.

complete.transphyseal.fracture.with.no.metaphyseal.fragment,.verifying.a.type.3.fracture .After.manual.replacement.

the.epiphysis.was.noted.to.be.stable.throughout.a.full.range.of.flexion,.extension,.and.forearm.rotation .A.long.arm.

cast.was.worn.19.days.followed.by.a.collar.and.cuff.for.2.weeks .d.Six.months.later,.age.7.years.3.months.there.was.full.

range.of.motion.with.normal.elbow.function .The.patient.was.seen.on.multiple.occasions.in.other.departments.of.the.

clinic.over.the.next.13.years.with.no.mention.of.elbow.difficulty

(14)

Fig. 21.10

Proximal.radius.type.2.fracture.with.ORIF .This.8.year.6.month.old.boy.fell.down.stairs.injuring.his.left.elbow.sustaining.

a.type.2.fracture .Closed.reduction.under.general.anesthesia.was.unsuccessful .Open.reduction.was.supplemented.

with.trans-articular.K-wire.fixation .A.posterior.plaster.splint.and.bulky.padded.bandage.was.applied .a.Four.days.post.

operative.maintenance.of.reduction.was.recorded.and.a.long.arm.cast.applied.with.the.elbow.in.90º.flexion.and.the.

forearm.in.neutral.rotation .b.Five.weeks.post.fracture.the.cast.was.removed.and.the.wire.was.noted.to.be.broken .The.

proximal.portion.was.removed.and.active.motion.begun .Four.days.after.cast.removal.the.distal.portion.of.the.wire.

was.removed.under.general.anesthesia.by.open.exposure.and.applying.varus.stress.to.the.elbow .c.One.year.post.

fracture,.age.9.years.6.months.the.elbow.was.clinically.normal.and.the.fracture.healed.and.remodeling.satisfactorily

(15)

Type 4

Type 4 fractures (Fig. 21.4) require precise anatomic reduction to restore articular congruity. This usually requires open reduction and internal fixation with small diameter transverse or oblique Kirschner wires to prevent displacement of the fragments during heal- ing (Fig. 21.11). The cartilaginous portion of the head

in a young child may be much larger than the osseous fragment seen on the roentgenograph (Fig. 21.11f).

The epiphyseal fragment may displace extra-articu- larly (Fig. 21.12), just like a type 3 fracture. A dis- placed epiphyseal fragment is usually irreducible by closed means. Open manual replacement of a large fragment sometimes achieves sufficient stability that no internal fixation is necessary (Fig. 21.12c).

Fig. 21.11

Proximal.radius.type.4.fracture.in.a.6.year.7.month.old.girl .a.AP.roentgenograph.of.the.injured.left.elbow.is.normal ..

b.Lateral.roentgenograph.shows.irregularity.in.the.anterior.portion.of.the.radial.epiphysis .c.Oblique.view.confirms.

fracture.of.anterior.proximal.radial.epiphysis,.type.4 .The.radius.does.not.align.precisely.with.the.capitellum .d.One.

week.after.injury,.oblique.view.shows.further.displacement.of.the.fracture.fragment.and.posterior.alignment.of.the.

radius.on.the.capitellum .This.suggests.that.the.original.injury.included.posterior.dislocation.of.proximal.radius,.and.

possibly.of.both.the.radius.and.ulna .(Continuation see next page)

(16)

(17)

É Fig. 21.11 (continued)

e.Closed.reduction.under.anesthesia.and.application.of.cast.with.elbow.in.extension.reveals.persistent.posterior.sub- luxation.of.the.radius.on.the.capitellum .f.Intraoperative.photograph.after.reduction.and.K-wire.fixation .There.was.no.

fracture.of.the.metaphysis,.confirming.a.type.4.fracture .Note.that.the.size.of.the.anterior.(upper).fragment.is.much.

larger.than.suspected.roentgenographically .The.intra-articular.flap.of.articular.cartilage.attached.to.the.intact.portion.

of.the.radial.head.was.excised .g.Intraoperative.lateral.roentgenograph.shows.small.K-wire.fixation.of.fracture.fragment.and.a.larger.K-wire.transarticular.longitudinal.pin.to.maintain.radial.alignment .h.AP.roentgenograph.at.time.of.

wire.removal.3 5.weeks.after.surgery .The.epiphysis.and.physis.appear.normal .i.One.year.8.months.after.fracture,.age.

8.years.3.months .The.patient.is.right.handed.and.has.no.complaints.about.her.left.elbow .She.can.easily.do.push-ups . She.lacks.the.final.10º.pronation.and.5º.supination.on.the.left .The.physis.and.metaphysis.are.normal .The.epiphyseal.

fragment.has.united.with.a.residual.cleft.anterolaterally .The.patient.was.seen.in.departments.other.than.orthopedics.

over.the.next.four.years.with.no.mention.of.elbow.difficulty .(Reprinted.from.Leung.and.Peterson.[14],.with.permission)

Fig. 21.12

Proximal.radius.type.4.fracture .This.14.year.7.month.old.girl.injured.her.left.elbow.in.a.fall .a.A.large.portion.of.the.

.radial.epiphysis.(arrows).lies.posterior.to.the.joint .b.The.fragment.was.found.in.soft.tissue.extra-articularly.(left).and.

had.no.periosteal.attachments.(right) .(Continuation see next page)

(18)

c.The.fragment.was.manually.replaced.and.noted.to.be.

stable.through.all.planes.of.rotation .No.internal.fixation.was.used .A.long.arm.bulky.compression.bandage.

was.changed.to.a.long.arm.cast.2.days.later .d.Three.

days. post. fracture. the. fragment. remained. reduced . The.long.arm.cast.was.worn.4 5.weeks .e.At.age.21.years.

0.months.(6.years.5.months.post.fracture).the.patient.

was. without. complaint,. functioning. normally,. and.

.elbow.examination.was.normal

(19)

Premature closure of the physis nearly always oc- curs [14, 21], but because the proximal radius accounts for only 20% of the growth of the radius and because types 4 and 5 injuries often occur in older children, problems from growth arrest are rare. Functional im- pairment, however, particularly limited forearm rota- tion, is common after type 4 fractures [14].

Type 5

Differentiation between type 4 and type 5 (Fig. 21.4) may be subtle and often requires precise rotation projection to document the metaphyseal fracture (Fig. 21.13a–c). Minimally displaced and relatively stable fractures can be treated closed. Extension of

Fig. 21.13

Proximal.radius.type.5.fracture .This.7.year.11.month.old.boy.injured.his.left.elbow .a.An.AP.view.shows.irregularity.of.

the.epiphyseal.articular.surface.and.a.small.metaphyseal.fragment.laterally .The.remainder.of.the.metaphysis.and.the.

physis.are.normal .b.An.AP.view.with.more.elbow.flexion.shows.a.sagittal.fracture.of.the.epiphysis .c.The.lateral.view.

shows.distal.displacement.of.the.anterior.epiphyseal.fragment,.along.with.its.corresponding.physis.and.metaphysis,.

confirming.a.type.5.fracture .Note.posterior.subluxation.of.the.proximal.radius.and.ulna.allowing.the.capitellum.to.

exert.pressure.on.the.anterior.portion.of.radial.head .A.long.arm.cast.was.applied.with.the.elbow.flexed.90º .(Continu- ation see next page)

(20)

e.One.day.after.fracture .The.cast.was.removed.and.the.

elbow.extended .Position.of.the.radial.epiphyseal.and.

metaphyseal. fragment. is. improved .f. Long. arm. cast.

.applied. with. elbow. in. extension. (oblique. view) . Ana- tomic. reduction. of. fragments. and. radial. alignment . . g.Eight.weeks.after.fracture,.age.8.years.1.month .Cast.

removed .Fractures.appear.to.be.healing.in.anatomic.

position .Note.new.subperiosteal.bone.on.lateral.side.

of. metaphysis . Apparent. healed. appearance. of. the.

epiphysis.is.due.to.the.rotation.of.the.radius .h.Eight.

months.after.fracture,.age.8.years.7.months .The.epiphysis.is.healing.with.an.anterior.opening .The.physis.is.

open .(Continuation see next page)

(21)

the elbow helps to tighten the joint capsule, helping to reduce fragments and align the radius on the capitel- lum (Fig. 21.13e, f). Displaced or unstable fractures

i.Five.year.8.months.after.fracture,.age.13.years.7.months .AP.radiograph.both.elbows .Note.enlargement.of.left.radial.

head.with.anterior.central.articular.surface.depression .j.Lateral.both.elbows .Note.satisfactory.alignment.of.radius.on.

capitellum .(Reprinted.from.Leung.and.Peterson.[14],.with.permission)

may be reduced and fixed from epiphysis to epiphysis.

This will lessen the potential for nonunion, but not

for premature physeal arrest (Fig. 21.14).

(22)

Fig. 21.14

Proximal. radius. type.5. fracture. in. a. 7.year. 0.month. old. girl .a. A. type.5. fracture. similar. to. that. in. Fig .21 13a–c. was.

opened,.reduced,.and.fixed.from.epiphysis.to.epiphysis.with.2.smooth.Kirschner.wires .b.Twenty.months.later.the.

.elbow.was.functioning.well,.but.there.was.a.large.physeal.bar.laterally .Observation.was.advised;.the.patient.was.lost.

to.follow-up

(23)

Type 6

Type 6 fracture (a part missing) is always an open in- jury and has a very poor prognosis (Fig. 21.15). Re- gardless of how little physis is lost, the remaining phy- sis always stops growing. Late reconstructive surgery is usually necessary.

Fig. 21.15

Proximal. radius. type.6. fracture . This. boy. was. 3.years.

8.months.old.when.his.left.elbow.was.lacerated.multiple.times.by.a.rotary.lawnmower .a.There.are.multiple.

osseous.fragments.and.severe.soft.tissue.damage.on.

the.medial.side.of.the.elbow .Absence.of.a.thin.slice.of.

the.ulnar.side.of.the.proximal.radial.head.and.neck.was.

visualized. and. removed. at. the. time. of. debridement,.

but.is.not.visible.on.the.particular.rotation.of.the.radius.

on.this.view .b.The.site.of.the.missing.fragment.from.

the.proximal.radius.(arrow).is.best.seen.on.the.post.reduction. roentgenograph .c. Eleven. months. later,. age.

4.years. 7.months,. there. is. limited. elbow. motion. and.

early. degenerative. arthrosis . The. poor. result. in. this.

case.is.due.more.to.the.severity.of.the.injury.than.to.the.

type.6.proximal.radius.fracture .(Reprinted.from.Leung.

and.Peterson.[14],.with.permission)

(24)

Excision of the Radial Head

Excision of the radial head in any child with signifi- cant growth remaining (three years or more) should be avoided [8, 14, 22]. It will result in ulnar plus wrist deformity (Fig. 21.16), cubitus valgus (Fig. 21.17), cap- itellar-radial degenerative changes, and possible ra- dioulnar synostosis (Fig. 8K.1d, e). Forearm rotation is often disappointingly limited. It may be necessary in a severely comminuted radial head fracture which is rare in a child. Radial head excision in this case may be superior to insertion of a radial head prosthesis, of which there have been no successful case reports in children. When a child has reached maturity, radial head excision for chronic pain and limited motion is appropriate, just as it is in adulthood [22].

Complications

Newman [19] listed 106 complications in 48 children with head and neck fractures: thickened radial neck (36), premature physeal arrest (24), enlarged radial head (20), ectopic ossification (12), avascular necrosis (9), and radioulnar synostosis (5). But he did not specify the number or type of complications from head fractures (25), neck fractures (20), or unspeci- fied fractures (3). Interestingly, he and others [32, 42]

noted that younger children (under age 10 years of age) had a higher percentage of good and excellent results than did older children. A widened radial neck is more likely to occur in neck fractures and is hardly a complication as it causes no morbidity.

Fig. 21.16

Proximal.radius.type.5.fracture .This.11.year.2.month.old.right.handed.boy.fell.in.gym.class.injuring.his.right.elbow ..

a.These.initial.roentgenographs.showed.soft.tissue.swelling.laterally.over.the.head.of.the.radius .A.sling.was.applied ..

b.Two.weeks.later.he.fell.in.a.school.bus.reinjuring.the.right.elbow .Roentgenographs.revealed.a.mildly.displaced.

type.5.fracture.of.the.radial.head,.possibly.2.weeks.old .The.sling.was.continued.an.additional.4.weeks .c.Three.months.

later,.age.11.years.5.months.there.was.no.sign.of.union.of.the.epiphysis .Increasing.pain.with.elbow.flexion.and.extension.was.noted .d.Ten.months.post.fracture,.age.12.years.0.months,.pain.was.increased.and.there.was.prominence.and.

tenderness.over.the.radial.head .Right.pronation.and.supination.were.80º,.flexion.15–110º .There.is.malunion.of.the.

epiphyseal. fragment. (left) . A. tomogram. (right). shows. a. large. lytic. defect. in. the. capitellum . (Continuation see next page)

(25)

(26)

e.AP.views.of.both.wrists.show.mild.positive.ulnar.variance.on.the.right .Chylectomy.and.recontouring.of.the.radial.

head.were.combined.with.joint.debridement .There.was.marked.loss.of.articular.cartilage.of.both.the.capitellum.and.

radius .f.Three.months.post.operative,.age.12.year.3.months,.all.elbow.physes.were.closing.and.the.main.complaint.was.

ongoing.pain .g.Radial.head.excision.was.combined.with.arrest.of.the.distal.ulnar.physis .Note.degenerative.irregularity.on.the.radial.head.articular.surface .(Continuation see next page)

(27)

h. Elbow. pain. was. significantly. reduced .i. Seventeen.

months. post. radial. head. excision,. age. 13.years.

8.months,.there.was.slight.clinical.increase.cubitus.valgus.on.the.right .(Continuation see next page)

(28)

(29)

É Fig. 21.16 (continued)

j.Four.years.1.month.post.radial.head.excision,.age.16.years.4.months,.there.is.ulnar.plus.wrist.deformity.(right).despite.

the.surgical.closure.of.the.distal.ulnar.physis .Note.ulnar.styloid.nonunion,.possibly.associated.with.the.ulnar.plus.deformity,.since.there.was.no.known.injury.of.the.distal.ulna .At.age.19.years.7.months.persistent.lateral.elbow.pain.resulted.in.arthroscopic.debridement,.revision.radial.head.excision,.anterior.capsulotomy,.and.posterior.decompression . k.Three.months.post.elbow.joint.debridement.(age.19.years.10.months).persistent.pain.resulted.in.cortisone.and.anal- gia.injection .The.diagnosis.was.axial.displacement.of.the.radius.causing.residual.impingement.of.the.proximal.stump.

against.the.capitellum .The.patient.was.a.laborer.required.to.frequently.lift.objects.greater.than.20.lbs .He.was.advised.

to.change.employment

Fig. 21.17

Proximal.radius.type.5.fracture .This.14.year.6.month.old.boy.fell.playing.basketball.injuring.his.right.elbow .He.finished.

playing.the.game .Elbow.pain.that.night.along.with.swelling.the.next.morning.prompted.a.physician.visit.the.next.

morning .a.AP.and.lateral.roentgenographs.show.normal.osseous.structures .The.distal.humeral.physes.are.essentially.

closed .b.One.oblique.view.(right).shows.faint.longitudinal.defects.in.the.radial.epiphysis.suggestive.of.a.type.4.fracture .A.long.arm.cast.with.the.elbow.in.70º.flexion.was.worn.9.days .(Continuation see next page)

(30)

c.Nine.days.post.injury.the.lateral.view.(right).shows.anterior.displacement.of.the.anterior.half.of.the.epiphysis.along.

with.a.tiny.metaphyseal.fragment.confirming.a.type.5.fracture .A.posterior.splint.was.applied .d.One.month.post.injury.there.was.increased.displacement.of.the.epiphyseal-metaphyseal.fragment.and.subperiosteal.new.bone,.support- ing.the.type.5.diagnosis .(Continuation see next page)

(31)

e. A. long. arm. cast. with. the. elbow. in. full. extension.

showed.improved.anatomy.of.the.radial.head .f.Three.

and.a.half.months.post.injury.there.was.enlargement.

of.the.radial.head.which.was.reasonably.aligned .Joint.

motion,.however,.was.markedly.restricted .(Continua- tion see next page)

(32)

g. An. arthrogram. showed. no. dye. between. the. radial.

head. and. capitellum .h. Eight. months. post. fracture.

there.was.enlargement. of.the.right.radial.head.(left) . Elbow.flexion.was.right.85–125º,.left.–5.to.155º;.forearm. supination. 5/95º. (R/L),. pronation. 60/85º. (R/L) . . i.The.radial.head.was.excised.at.age.15.years.2.months . Motion. was. not. improved . At. age. 16.years. 1.month. . an.extensive.anklyosis.“take-down”.operation.was.per- formed .Intra-articular.adhesions.with.ectopic.bone.in.

the.coronoid.fossa.and.on.the.coronoid.were.removed . Post.operative.continuous.passive.motion.and.dynamic.

splinting.were.used .(Continuation see next page)

(33)

In the Olmsted County study [27], of six proximal ra- dial physeal fractures, one patient (17%) developed one complication (Table 8.6), an angular deformity (Table 8.1).

Physeal Arrest

Most proximal radial physeal fractures, particularly in older children, result in premature complete arrest.

Abnormal cam motion may occur with forearm rota- tion. The physeal closure may be related to mild degrees of cubitus valgus [21], but has not resulted in a published case of relative radial shortening (ulnar plus wrist deformity) sufficient to require treatment.

Partial radial head closure occurs infrequently (Fig. 21.14b). Reports of bar excision in the proximal radius are rare (Table 33.3). Surgical exposure of a central bar would be difficult.

Enlargement of the Radial Head

There is noticeable circumferential overgrowth of the radial head, as compared with the uninjured side, in virtually every child with a proximal radial physeal fracture (Fig. 21.13i). Mild enlargement usu- ally has no deleterious effects. However, if the enlargement is eccentric it may cause diminished forearm rotation.

Loss of Motion

Loss of mild degrees of rotation and extension is com- mon, may be associated with tightened joint capsule or ligamentous strictures, and usually does not reduce function. Offset of the radial head-shaft alignment, however, produces a rotation cam effect of the radial head against the capitellum predisposing it to degen- erative arthrosis. Loss of joint motion, even if signifi- cant, should be accepted during the growing years.

If there is significant growth remaining the radial head should not be excised since it will result in ulnar plus wrist deformity. When the patient reaches matu- rity the radial head may be excised with little risk of developing wrist deformity. However, the return of motion is usually disappointing. If forearm rotation is limited due to radial head deformity it would be expected that radial head excision would allow re- sumption of rotation. This frequently does not occur (Fig. 21.17). The primary indication for excision of the radial head is pain.

Delayed Union

Delayed union is not uncommon in radial head frac- tures (Figs. 21.13h, 21.16c).

Malunion

Malunion predisposes to degenerative arthrosis (Fig.

21.16d).

j.Seven.months.later,.age.16.years.8.months,.pain.was.no.longer.a.problem,.but.elbow.and.forearm.motion.were .There.

was.only.10º.elbow.flexion.(from.70.to.80º) .Forearm.rotation.was.the.same.as.in.i .The.patient.had.adapted.to.his.

.limited.motion,.had.returned.to.high.school.football.and.basketball,.and.declined.further.treatment

(34)

Fig. 21.18

Proximal.radius.type.5.fracture.with.nonunion .This.12.year.11.month.old.right.handed.boy.fell.from.a.tree.injuring.his.

right.elbow .a.AP.and.lateral.roentgenographs.were.normal.except.for.mild.soft.tissue.swelling.laterally.at.the.joint.

level .No.oblique.films.were.obtained .The.only.treatment.was.physical.therapy.for.several.weeks .All.motion.was.regained .b.Nine.months.post.injury,.age.13.years.8.months,.he.noted.instability.while.attempting.to.throw.a.baseball . There.was.mature.subperiosteal.new.bone.on.the.proximal.radial.metaphysis.(arrows,.left).and.a.poorly.visualized.

.anterior.prominence.of.the.radial.epiphysis.(arrow,.right) .(Continuation see next page)

(35)

Nonunion

Nonunion is not uncommon and is most likely to occur following unrecognized or untreated type 4 or type 5 fracture (Fig. 21.18c).

Heterotopic Bone

Children have a predisposition to absorb ectopic cal- cification before it becomes mature bone. Thus, chil- dren are much less likely than adults to develop het- erotopic bone after elbow injury [41]. Minor amounts of posttraumatic heterotopic bone formation are probably common [42, 43], but not frequently report- ed which suggests it rarely causes symptoms.

Ischemic Necrosis

Although the vascular supply of the radial epiphysis is similar to that of the proximal femur [47], ischemic necrosis is uncommon even when the head is com- pletely separated (type 2 and 3 fractures) [33, 42]. Per- haps revascularization of such a small volume of tis- sue is quickly accomplished.

Synostosis

Radioulnar synostosis following proximal radial phy- seal fractures (Fig. 8K.1b) is not uncommon. Synosto- sis may also occur following excision of the radial head and neck (Fig. 8K.1e) [6, 7, 19, 21, 33, 34, 43–45].

Treatment of synostosis by prosthetic replacement of the head was partially successful in one case [45].

Achieving a position of optimal forearm rotation, by osteotomy if necessary, may be the treatment of choice.

c.One.year.post.injury,.age.13.years.11.months.the.AP.

view.(left).shows.normal.osseous.anatomy,.but.the.lateral.(middle).and.oblique.(right).views.confirm.a.well.

established. nonunion. of. a. type.4. or. 5. fracture . The.

subperiosteal.new.bone.extending.distally.along.the.

radial. neck. favors. a. type.5. fracture .d. On. another.

oblique. view. the. main. portion. of. the. radial. head. is.

.positioned.laterally.relative.to.the.capitellum,.which.is.

wedging. between. the. two. fragments . (Continuation see next page)

(36)

e.Two.years.post.injury,.age.14.years.11.months,.there.was.catching.and.locking.of.the.elbow.several.times.daily .f.Two.

years.11.months.post.injury,.age.15.years.10.months,.degenerative.arthrosis.is.firmly.established .The.patient.has.pain.

and.diminished.motion .Note:.The.best.way.to.avoid.this.unfortunate.sequence.of.events.is.a.more.concerted.effort.to.

establish.a.diagnosis.at.the.time.of.injury,.and.treat.it.accordingly

(37)

Irreducible

Type 2, 3, and 4 fractures have been known to dis- place through a buttonhole-like rent in the annular ligament. These cannot be reduced closed and must be opened. Following reduction some may stabilize and not require internal fixation (Fig. 21.9c) [22].

Neuropathy

Posterior interosseous nerve palsy has been reported in association with head and neck fractures [2], but whether the fracture was in the head or the neck was not specified.

Compartment Syndrome

One volar compartment syndrome of the forearm was identified following a minimally displaced type 2 fracture of the radial head in a 6-year-old child [23].

References

1. Arcalis Arce A, Marti Garin D, Molero Garcia V, Pede- monte Jansana J: Treatment of radial head fractures using a fibrin adhesive seal: a review of 15 cases. J Bone Joint Surg 77B:422-424, 1995

2. Bennett JB: Radial head fractures: diagnosis and management. J Shoulder Elbow Surg 2:264-273, 1993

3. Benz G, Roth H: Therapeutic problems with fractures of the radial head in children [German]. Z Kinderchir 40:289- 293, 1985

4. D’Souza S, Vaishya R, Klenerman L: Management of radial neck fractures in children: A retrospective analysis of one hundred patients. J Pediatr Orthop 13:232-238, 1993 5. Ehrensperger J: Osteosynthesis of proximal radius frac-

tures using polydioxanona pins [German]. Z Unfallchir Versicherungsmed 83:84-90, 1990

6. Fielding JW: Radio-ulnar crossed union following displacement of the proximal radial epiphysis. A case report.

J Bone Joint Surg 46A:1277-1278, 1964

7. Gaston SR, Smith FM, Baab OD: Epiphyseal injuries of the radial head and neck. Am J Surg 85:266-254, 1953 8. Havránek P, Hájková H: Treatment of children’s epiphy-

seal injuries in the elbow region. Acta Univ Carol Medica 31:243-268, 1985

9. Henriksson B: Isolated fractures of the proximal end of the radius in children: Epidemiology, treatment, and prognosis. Acta Orthop Scand 40:246-260, 1969

10. Jeffrey CC: Fractures of the head of the radius in children.

J Bone Joint Surg 32B:314-324, 1950

11. Jones E, Esah M: Displaced fractures of the neck of the radius in children. J Bone Joint Surg 53B:429-439, 1971 12. Key JA: Treatment of fractures of the head and neck of the

radius. J Am Med Assoc 96:101-104, 1931

13. Landin LA, Danielsson LG: Elbow fractures in children.

An epidemiologic analysis of 589 cases. Acta Orthop Scand 57:309-312, 1986

14. Leung AG, Peterson HA: Fractures of the proximal radial head and neck, with emphasis on those that involve the articular cartilage. J Pediatr Orthop 20:7-14, 2000

15. McBride ED, Monnet JC: Epiphyseal fractures of the head of the radius in children. Clin Orthop 16:264-271, 1960 16. McCarthy SM, Ogden JA: Radiology of postnatal skeletal

development: VI: Elbow joint, proximal radius, and ulna.

Skel Radiol 9:17-26, 1982

17. Mizuta T, Benson WM, Foster BK, Patterson OL, Morris LL: Statistical analysis of the incidence of physeal injuries.

J Pediatr Orthop 71:518-523, 1987

18. Montgomery AH: Separation of the upper epiphysis of the radius. Arch Surg 10:961-968, 1925

19. Newman JH: Displaced radial neck fractures in children.

Injury 9:114-121, 1977

20. Nussbaum AJ: The off-profile proximal radial epiphysis:

Another potential pitfall in the diagnosis of elbow trauma.

J Trauma 23:40-46, 1983

21. O’Brien PI: Fractures involving the proximal radial epiphysis. Clin Orthop 41:51-58, 1965

22. Payne JF, Earle JL: Fracture dislocation of the proximal radial epiphysis. Minn Med 52:479, 1969

23. Peters CL, Scott SM: Compartment syndrome in the forearm following fractures of the radial head or neck in children. J Bone Joint Surg 77A:1070-1074, 1995

24. Peterson HA: Physeal fractures of the elbow. In: Morrey BF (ed). The Elbow and Its Disorders. W B Saunders Co., Philadelphia, 3rd edn, 2000, Chapter 17, pp 219-235 25. Peterson HA: Physeal fractures: Part 2, Two previously un-

classified types. J Pediatr Orthop 14:431-438, 1994 26. Peterson HA: Physeal fractures: Part 3, Classification. J Pe-

diatr Orthop 14:439-448, 1994

27. Peterson HA, Madhok R, Benson JT, Ilstrup DM, Melton III LJ: Physeal fractures: Part 1, Epidemiology in Olmsted County, Minnesota, 1979-1988. J Pediatr Orthop 14:423- 430, 1994

28. Pritchett JW: Growth and predictions of growth in the upper extremity. J Bone Joint Surg 70A:520-525, 1988 29. Pritchett JW: Growth plate activity in the upper extremity.

Clin Orthop 268:235-242, 1991

30. Pritchett JW: Practical Bone Growth. JW Pritchett, Seattle, 1993, p 161

31. Pyle I, Sontag LW: Variability in onset of ossification in epiphyses and short bones of the extremities. Am J Roent- genol 49:795-798, 1943

32. Reidy JA, VanGorder GW: Treatment of displacement of proximal radial epiphysis. J Bone Joint Surg 45A:1355- 1372, 1963

33. Rodriguez-Merchan EC: Displaced fractures of the head and neck of the radius in children: Open reduction and temporary transarticular internal fixation. Review article.

Orthopedics 14:697-700, 1991

34. Roy DR: Radioulnar synostosis following proximal radial fracture in a child. Orthop Rev 15:89-94, 1986

35. Schwartz RP, Young F: Treatment of fractures of the head and neck of the radius and slipped radial epiphysis in children. Surg Gynec and Obstet 57:528-537, 1933

36. Sessa S, Lascombes P, Prevot J, Gagneux E: Fractures of the radial head and associated elbow injuries in children.

J Pediatr Orthop 5:200, 1996

37. Silberstein MJ, Brodeur AE, Graviss ER: Some vagaries of the radial head and neck. J Bone Joint Surg 64A:1153, 1982

(38)

732 Chapter 21 Proximal Radius 38. Sponseller PD: Problem fractures in children. Hand Clin

10:495-505, 1994

39. Steinberg EL, Golomb D, Salama R, Weintroub S: Radial head and neck fractures in children. J Pediatr Orthop 8:35- 40, 1988

40. Svensson P, Janarv P, Hirsch G: Internal fixation with biodegradable rods in pediatric fractures: One-year follow-up of 50 patients. Pediatr Orthop 14:220-224, 1994

41. Thompson HC, Garcia A: Myositis ossificans: Aftermath of elbow injuries. Clin Orthop 50:129-134, 1967

42. Tibone JE, Stoltz M: Fractures of the radial head and neck in children. J Bone Joint Surg 63A:100-106, 1981

43. Vahvanen V, Gripenberg L: Fracture of the radial neck in children. Acta Orthop Scand 49:32-38, 1978

44. van Vugt AB: Surgical treatment of fractures of the proximal end of the radius in childhood. Arch Orthop Trauma Surg 104:37-41, 1985

45. Vince KG, Miller JE: Cross-union complicating fracture of the forearm. J Bone Joint Surg 69A:654-661, 1987

46. Wood SK: Reversal of the radial head during reduction of a fracture of the neck of the radius in children: report of two cases. J Bone Joint Surg 51B:707-710, 1969

47. Young S, Letts M, Jarvis J: Avascular necrosis of the radial head in children. J Pediatr Orthop 20:15-18, 2000