Common Upper Extremity Injuries in Children
Clavicle Injuries
The Clavicle is the first
bone to ossify (between the fifth and sixth weeks of fetal life), and the last
bone in which physeal closure is observed (approximately 25 years of age).
Fractures of the clavicle can occur in any age group, from neonate to adult,
and can involve any portion of the clavicle from sternum to acromion.
Fractures of the clavicle at
the time of birth are the most common fracture in newborns. Generally, the
diagnosis is made by the pediatrician when observing an asymmetric Moro reflex,
and/or the child’s unwillingness to move the affected upper extremity, termed
pseudoparalysis. Great care must be taken to rule out coincident brachial
plexus injury. Treatment is typically
non-operative with immobilization of the affected limb to the chest wall, and
long-term sequelae are extremely rare.
In the growing child,
clavicular shaft fractures are one of the more commonly observed skeletal
injuries. History usually includes a fall on the point of the shoulder,
and the presence of tenderness and swelling around the mid-clavicle will
generally allow for prompt diagnosis. Most of these fractures will be of the
greenstick variety. Immobilization with a sling and swathe or figure of eight
brace will usually suffice for treatment. Callus healing will often lead to a
visible and palpable bump in the region of healing, and can cause alarm in
caregivers that have not been properly forewarned.
Fractures of either the
medial or distal ends of the clavicle often include some degree of physeal involvement,
and should be carefully evaluated. Again, sling and swathe immobilization will
adequately protect against re-injury, and will allow satisfactory healing. On
very rare occasion, posterior displacement of medial physeal injury is
observed, and sometimes requires open reduction and fixation to prevent risk to
the contents of the thoracic cavity.
Proximal Humerus Injuries
Proximal humerus fractures
represent less than 5% of children's fractures. These can be physeal injuries.
It is important to understand the normal radiographic anatomy of the proximal
humeral physis, so that the diagnosis can be made accurately, and the degree of
physeal involvement can be assessed. This physis is not planar, but rather is
tent-shaped, with the apex posteromedially. Under age 5, these injuries are
typically Salter-Harris type I, whereas after age 11, they are typically SH
type II.
In the newborn
sub-population, proximal humeral injuries can be challenging to diagnose, given
the preponderance of cartilage in this region, and the resultant radiolucency.
This injury is common in the newborn nursery as a result of birth trauma, and
can manifest itself as pseudoparalysis. Fortunately, nonoperative treatment is
usually adequate. This is due, in part, to the fact that 80% of humeral growth
occurs proximally, allowing tremendous remodeling potential. In fact angulation
of up to 45° will have disappeared
by 6 months of age.
Goals of reduction include
angulation less than 45°
and displacement of less than 70%. If adequate reduction is possible,
non-operative treatment will yield acceptable results. In very rare cases,
where reduction cannot be maintained, percutaneous pinning may be required,
though usually only in children over age 12.
Spiral fractures of the
humeral shaft are an entity worth mentioning. Particularly in the child under
three years old, the torsional mechanism required to create this mode of
failure, is often telling of child abuse. In fact, about 80-90% of shaft
fractures in children under 3 are thought to be due to abuse.
Fractures About the Elbow
Radiographs
The standard radiographs of
the elbow include an anteroposterior view with the elbow extended and a lateral
view with the elbow flexed to 90° and the forearm neutral. If a line is drawn
along the anterior border of the distal humeral shaft, it should pass through
the middle third of the ossification center of the capitellum. This is referred
to as the anterior humeral line. A line directed proximally along the anterior
border of the coronoid process should barely touch the anterior portion of the
lateral humeral condyle. This is called the coronoid line. A line drawn down
the shaft of the radius should pass through the capitellum. This is called the
radiocapitellar line. Because of the ever-changing ossification pattern,
identification and delineation of fractures about the elbow in the immature
skeleton may be subject to misinterpretation. Some vagaries of the ossification
process about the elbow may be interpreted as a fracture. It is therefore
imperative to understand the relative time interval of formation of each of the
six ossification centers around the elbow. The ossification center of the
capitellum appears first at about 6 months. At intervals of roughly 2 years the
remaining ossification centers form in the following order; radial head, medial
epicondyle, trochlea, olecranon, lateral epicondyle
Other important radiographic findings to be familiar
with include the fat pad sign. There are fat pads that overlie the capsule in
the coronoid fossa anteriorly and the olecranon fossa posteriorly. Because of
their location deep within these fossae, they are generally not visible
radiographically. in the presence of a joint effusion, however, displacement of
either or both of these fat pads may become apparent. Presence of a posterior
fat pad sign is the most telling, and should be considered a fracture until
proven otherwise.
Supracondylar Humerus Fractures
Children often extend their
elbows to break the force of a fall. Because of ligamentous laxity, the elbow
hyperextends, allowing the linear force applied along the extended elbow to be
converted to a bending force. This bending force is then concentrated by the
olecranon into the anatomically weak supracondylar area producing a supracondylar
fracture. As extension type (98%) supracondylar humerus fractures are far more
common than flexion type (2%), we will focus on them here.
Age is the key factor in the incidence of supracondylar fractures.
This fracture, without intra-articular extension, is almost exclusively a
phenomenon of the immature skeleton. Incidence increases during the first 5
years and peaks at 5 to 8 years of age. After this, there is a decrease in
incidence until age 15, after which it is rare. This decrease in the incidence
of supracondylar fractures is replaced by a rising incidence of elbow
dislocations. Males sustain almost twice as many supracondylar fractures as
females
.
Nerve injuries occur in
about 8% of these extension-type injuries. The most commonly injured is the
anterior interosseous, followed by the radial and ulnar in descending order.
The ulnar is the most common injured nerve in flexion-type supracondylar
fractures.
Vascular injury is another
significant concern in treating these fractures. The brachial artery is
particularly susceptible to injury in hyperextension type injuries, and can
lead to a compartment syndrome. Undiagnosed and prolonged compartment syndromes
of the forearm can cause a specific clinical entity known as Volkmann’s ischemic
contracture, though this has been described as occurring in only 0.5% of cases
(and even far fewer in a recent conference poll of many of our pediatric
staff). Historically, these injuries were treated with casting in hyperflexion,
which led to a high rate of Volkmann’s contracture, but with the advent of
percutaneous pinning techniques (see below), the arm could now be immobilized
at 70-80 degrees of flexion yielding markedly decreased rates of this
complication.
Gartland’s classification is a simple system that is widely
accepted. In type I injuries the fracture is non-displaced or minimally
displaced such that the anterior humeral line still passes through the
ossification center of the capitellum on the lateral radiograph. In type II
injuries there is an obvious fracture line with displacement of the distal
fragment, but there is still an intact cortex posteriorly. In type III
injuries the fragments are completely displaced.
Non-displaced, or type I,
supracondylar fractures usually require no more than simple immobilization for
comfort and further protection. Once the neurovascular assessment is made,
placing the extremity in either a posterior splint or circular cast is all that
is necessary. The decision of whether to hospitalize the child for a brief
period of observation usually depends on the degree of soft-tissue swelling and
discomfort and the reliability of the parents. By 3 weeks after injury, the
pain and swelling usually have significantly subsided to allow a protected
active range of motion. X-ray evaluation at this time usually reveals
periosteal new bone formation in the supracondylar area of the humerus.
Treatment of type II
fractures involves relaxation of the patient, manipulation and casting or
splinting. Sometimes percutaneous fixation is necessary to prevent the
deformity from recurring or to avoid the need for immobilization in more than
70 or 80° of flexion. Adequate
relaxation often requires a general anesthetic, so as to allow the surgeon to
better manipulate the fracture fragments.
Manipulation is carried out with the goal of approximating the carrying
angle of the uninjured side. Hyperflexion with the arm in a fully pronated
position will generally reduce these fractures. Maintaining this reduction, can
be challenging as the arm should remain in a position of 125-135 degrees of
flexion. if there is any concern regarding the degree of swelling, and the
added vascular compromise that this may impose, one should not hesitate to
consider percutaneous pin placement for added stability, allowing the arm to be
held in 90 degrees or less of flexion.
Treatment of type III
injuries must follow the following three steps. First, there must be some type
of manipulation to obtain a reduction of the fracture. Second, once the
fracture is reduced, the quality of the reduction must be assessed. And third,
the reduction must be maintained until the fracture is healed enough to be
intrinsically stable. Historically, there are many different approaches to
treatment of these injuries, but for the sake of simplicity, we will herein
discuss only the gold standard, percutaneous pin fixation with splinting or casting.
Stabilization of reduced
type III fractures with pins placed percutaneously has become the universally
accepted method of treatment. Pins may be placed from medial to lateral,
lateral to medial, or both. Most surgeons will elect to place either 1)
crossing k-wires, one from each side or 2) parallel pins placed lateral to
medial (which helps avoid injury to the ulnar nerve, but compromises some
amount of stability). In particularly unstable fracture patterns, many will
elect to place two parallel lateral to medial pins, and a third medial to
lateral that crosses these first two.
Incidence of injury to the ulnar nerve is estimated
to be 2% to 3%. In the reports of ulnar nerve injury occurring after pin fixation,
most cases will clear spontaneously after removal of the offending pin.
Further management generally
consists of three or four weeks of immobilization, followed by removal of
pins in the office, and active range of motion started at the child's own
pace. Strategies for prevention of reinjury include continued splinting during
play, or simple sling use for an additional 3-4 weeks time, or until tenderness
resolves and the child has begun to use the arm freely without difficulty.
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Cubitus varus (figure
17-14), or varus angulation through the region of the elbow, is the
most common late deformity associated with a supracondylar humerus fracture.
Typically it is caused by malreduction or failure to maintain an adequate
reduction, but can also occur due to osteonecrosis of the trochlea.
If the deformity is excessive, and is cosmetically objectionable to
the patient and family, a corrective supracondylar osteotomy can be
performed.
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Condylar Fractures
Fractures of the lateral
condylar physis constitute about 17% of fractures of the distal humerus. Fractures
involving the lateral condylar region in the immature skeleton either cross
the physis (Milch type I) or follow it for a short distance into the trochlea
(Milch type II). The diagnosis of these injuries may be less obvious both
clinically and radiographically than that of supracondylar fractures, especially
if the fracture is minimally displaced. These injuries are a challenge to
treat, and typically have worse outcomes than suprcondylar injuries due to
the poor blood supply of the fracture fragment, and because they are intra-articular
and transphyseal.
Fractures of the lateral
condylar physis are only occasionally associated with injuries outside the
elbow region. Within the elbow region, the associated injuries that can occur
with this fracture include dislocation of the elbow (which may be a result
of the injury to the lateral condylar physis rather than a separate injury),
fractures of the radial head, and fractures of the olecranon, which are often
greenstick in nature.
The incidence of a
functional loss of range of motion in the elbow is considerable with fractures
of the lateral condylar physis because the fracture line often extends into the
articular surface. A difficult supracondylar fracture with cubitus varus,
barring the immediate neurovascular complications, is likely to result in a
surgically correctible cosmetic deformity with an essentially normal range of
motion in the elbow. A poorly treated lateral condylar physeal injury, however,
is likely to result in a significant loss of range of motion that is not as
responsive to surgical correction.
A Milch Type I lateral
condylar injury is a true Salter-Harris type IV injury through the ossific
nucleus of the lateral condyle. In this type, the fracture line originates in
the metaphysis, crosses the physis more or less obliquely, and finally
traverses the ossification center of the lateral condylar epiphysis to exit in
the area of the capitulotrochlear groove. A Milch Type II injury is more common, and shares characteristics of
both Salter-Harris II and III type physeal injuries. The most common fracture
line originates in the posterolateral metaphysis, where there is a fragment of
variable size. The fracture then usually courses within the physis down to the
depths of the trochlea. In this most common type, the fracture line does not
traverse the lateral condylar epiphysis or ossification center. The
ossification center of the lateral condyle extends to the lateral crista of the
trochlea. Thus, the terminal portion of the fracture line courses through the
physeal cartilage that lies between the ossification centers of the lateral
condyle and the medial condyle. Treatment guidelines follow those of a type IV
injury: open reduction and internal fixation of displaced intra-articular
fractures, with the potential for mild growth disturbance of the distal humeral
physis.
Notice in figure 10-66 how
such a small sliver of bone can actually represent a larger fracture when
considering the non-ossified portions of the distal humerus.
There are three alternatives
for managing fractures involving the lateral condylar physis: simple
immobilization alone, reduction by closed methods, or open surgical
reduction.
Minimally displaced
fractures are stable and have considerable intrinsic soft-tissue attachments
that prevent displacement of the distal fragment. About 20% of lateral condylar
physeal fractures are sufficiently nondisplaced that they can be treated by
simple immobilization without surgical intervention
Because of the high
incidence of poor functional and cosmetic results with closed reduction
methods, open reduction has become the most widely advocated method for
unstable fractures with appreciable displacement. Smooth pins are the most
popular method of fixation.
Fractures of the medial
humeral condyle occur with about half the frequency of lateral condyle
injuries. This is generally an avulsion type injury, and can often be
associated with elbow dislocation. As such is the case, after reduction of an
elbow dislocation, it is very important to check post-reduction films to be
sure that there are no bony fragments of a medial condyle fracture that have become
entrapped in the joint.
These injuries were also
classified by Milch, and are divided into three types. Type I fractures begin
in the metaphysis and traverse the apex of the trochlea. Type II injuries start
in a similar manner and exit the groove between the capitellum and trochlea.
Type III injuries can be either of these types with significant displacement or
rotational mal-alignment. Displacement over 5mm is usually an indication for
operative management, and generally smooth pin placement is the procedure of
choice, though screw fixation is preferred by some (see figure 17-17)
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Injuries to the proximal
radius make up about 10% of fractures about the elbow. Usually, the insult
is to either the radial neck or the proximal radial physis. These injuries
are graded based on the degree of angulation, though it is most important
to remember simply that somewhere between 15 and 30 degrees of angulation
is the upper limit of acceptability for most authors. Closed reduction should
be attempted first, but failing that, consideration can be given to percutaneous
pinning. With any proximal radial injury, the ulna should be very closely
evaluated to rule out plastic deformation suggestive of a Monteggia type injury
(see below). As a rule, the posterior border of the ulna should be completely
straight. Any deviation from this should be considered bony injury.
Forearm Injuries
Forearm fractures account
for about 45% of fractures in children. Approximately 75% occur in the distal third,
20% in the middle third and 5% in the proximal
third. Most forearm fractures in children are the result of a fall on
the outstretched hand. Often the abbreviation FOOSH will be used in medical
documentation to indicate this mechanism of injury. Generally the arm is in a
position of relative pronation, and the fall creates a supination force,
resulting in the commonly found apex anterior supinated deformity.
In evaluating forearm
fractures, the deforming muscular forces should be kept in mind to help
understand the reasons for the presenting radiographic and clinical appearance,
and treatment rationale (figure 17-19). Distal fractures are often deformed by
the brachioradialis, while middle third fractures are more involved. The
supinator and biceps tend to flex and supinate a proximal radius fragment,
while the pronator teres can serve to pronate a distal radius fragment. Knowing
these muscular insertions, can aid in reduction maneuvers, and can help in the
planning of immobilization.
As with all orthopedic
injuries, forearm injuries should be evaluated
with radiographs of the joint above and the joint below the injury to be
certain that elbow and wrist involvement are not missed.
In general, forearm
fractures can be treated non-operatively in a long arm cast with satisfactory
results reported in about 85% of cases. Reports of loss of pronation and
supination have however turned the tide of management options somewhat, and
have led to increasing enthusiasm for operative management.
Some specific forearm
injuries that warrant further attention include distal radial physeal injuries,
Monteggia fracture dislocations and Galeazzi fracture dislocations.
Distal radial physeal
injuries are the most common physeal injuries incurred by juvenile long bones.
75% occur around the onset of puberty. Most of these are Salter-Harris II type
injuries, though in younger children, they tend to be of the Salter-Harris I
type. Frequently, they can be treated non-operatively with closed reduction and
casting. Most authors will start with long-arm casting and progress to short
arm casting once callus formation is visible radiographically. Partial or
complete growth arrest is observed in 5-10% of cases.
Monteggia Fractures
First described by Giovanni
Battista Monteggia in 1814, fracture dislocations involving dislocation of the
redial head accompanied by a proximal ulna fracture, are termed Monteggia
fractures. The ulnar fracture can be complete, incomplete or just plastically
deformed. Jose Luis Bado worked extensively
in further characterizing these injuries, and gave us a simplified
classification system based on the mechanism of injury.
A Bado type I injury involves an anterior dislocation of the
radial head with a fracture of the ulnar diaphysis. This represents about 70%
of all Monteggia lesions in pediatric populations. The type II lesion is
a posterior dislocation of the radial head associated with an ulnar diaphyseal
or metaphyseal fracture with posterior angulation. It is uncommon in children,
with most of the early series categorizing this as a fracture of adults only.
The type III lesion consists of a lateral or anterolateral dislocation
of the radial head associated with a fracture of the ulnar metaphysis. In
children, the metaphyseal fracture is generally of the greenstick variety. This
pattern represents about 23% of the lesions in children and is, therefore, the
second most common type of Monteggia fracture in children. It is often
associated with radial nerve injuries. The type IV Monteggia lesion,
also rare in children, is the association of anterior dislocation of the radial
head, fracture of the middle third of the radius, and fracture of the ulna at
the same level as, or more proximal to, the radius fracture.
Associated Nerve Injuries
There is a close relation
between the posterior interosseous nerve and the proximal radius, as the nerve
comes anterior and anterolateral to the radial head and neck on its path
through the supinator muscle. With anterolateral dislocations of the radial head,
this relation becomes particularly intimate, causing a paresis of the nerve. In
adults, there is a more discrete organization of the proximal border of the
superficial head of the supinator, forming the arcade of Frohse. This band is
not as well defined in children and, therefore, may partially account for the
lower incidence of permanent injury to the posterior interosseous nerve, as
well as the high incidence of resolution once the reduction of the radius is
obtained.
The ulnar nerve is
relatively tethered by the cubital tunnel and can be at risk in Monteggia
fractures involving the proximal end of the ulna, particularly type II
injuries.
Nonoperative treatment
should generally involve three steps: correct the ulnar deformity, provide a
stable reduction of the radial head, and relieve the deforming muscle forces,
preventing recurrent radial head dislocation and ulnar angulation.
The first step is to
reestablish the length of the ulna by longitudinal traction and manual
correction of any angular deformities present. The forearm is held in relaxed
supination as longitudinal traction is applied, with manual pressure directed
over the apex until the angular deformity is corrected clinically and
radiographically. With greenstick fractures, the plastic deformity must be
corrected or the fracture completed to prevent recurrence of the angular
deformity and/or re-dislocation of the radial head. Up to 10° of angulation is
acceptable in a complete fracture, providing a concentric radial head reduction
is maintained.
Once ulnar length and
alignment have been reestablished, the radial head can be located. This is
often accomplished simply by flexing the elbow to 90° or above, thus producing
spontaneous reduction. Occasionally, posteriorly directed pressure over the
anterior aspect of the radial head is necessary to facilitate reduction. Once
the radial head position is thought to be established, it should be scrutinized
radiographically in numerous views to ensure a concentric reduction.
Flexion of the elbow to
between 110 and 120° stabilizes the reduction of the radial head by alleviating
the force of the biceps, which could redislocate the radial head. The forearm
is placed in a position of midsupination to neutral rotation to alleviate the
forces of the supinator muscle and the anconeus, as well as the forearm
flexors, which tend to produce radial angulation of the ulna.
Once the fracture is reduced
and the neutral position is established, an above elbow cast or sugar tong
splint can be applied. The plaster should be molded using three contact points
to prevent recurrent angulation of the ulna. Once the cast is completed,
careful radiographic assessment should be performed, and necessary changes
made.
The patient is followed at
7- to 10-day intervals to confirm continued satisfactory reduction by
radiography. At 3 to 4 weeks after the initial reduction, the above elbow cast
is changed to a below elbow cast to allow early range of motion of the forearm,
particularly pronation and supination. Full activity is allowed at 6 to 8 weeks
after injury.
Although uncommon, there are
two indications for operative treatment of the Monteggia fracture dislocation:
failure of ulnar reduction and failure to reduce the radial head.
Galeazzi Fracture Dislocations
Although rare in children,
another commonly pimped eponym is that of the Galeazzi fracture. Riccardo
Galeazzi from Milan first described fractures of the distal radius associated
with disruption of the distal radioulnar joint (DRUJ) in 1934.
In the uninjured wrist,
little motion of the ulna occurs at the DRUJ due to the stabilizing forces of
the ulnar collateral ligament, the volar and dorsal radiocarpal ligaments, the
pronator quadratus muscle, the triangular fibrocartilage, and the dorsal and
volar distal radioulnar ligaments. The exact mechanism that produces injury to
these stabilizing structures is not well defined. It is established, however,
that extremes of rotation and axial loading can contribute. Typically, the ulna
will be dorsally displaced.
In two major reports that
address treatment in children, investigators achieved good results in 90% of
injuries treated by closed reduction alone. This is quite different from the
adult counterpart of this injury, which is known as the “fracture of necessity,”
meaning that operative intervention is a must. For Galeazzi fractures with a
dorsally displaced ulna, there seems to be agreement that the optimal position
of immobilization is with the forearm in supination. With the less common volar
displacement, however, there have been reports of successful treatment in both
supination and pronation.
The three major indications
for operative management are instability with secondary proximal migration of
the distal radial fracture fragment, inability to reduce the DRUJ due to
interposed tendons, and inability to reduce the distal ulnar physis.
Hand and Wrist Injuries
Distal Radius Fractures
The distal forearm deserves
special emphasis when discussing fractures in children because it is the most
common area to sustain a fracture in the immature skeleton. As well, in many
series, the distal radial physis is the most common pediatric physeal injury.
Compared to the adult,
distal radial fractures in children are rarely intra-articular. Radial
collapse, loss of wrist motion, and distal radioulnar joint dysfunction—all
common problems associated with distal radial fractures in the adult—are rare
after pediatric distal radius fractures. The incidence of complications and
poor results is also relatively low in children. In one series of 1346
fractures of the forearm, only 7% required remanipulation. In another series of
1767 fractures, only 2.5% had any significant residual angulation. The distal
radius has enormous remodeling potential due to the fact that 70-80% of forearm
growth occurs distally. This may account for this low rate of unacceptable
results.
The usual cause of a distal
forearm fracture is the patient's attempt to break a fall with an outstretched
hand. Usually the wrist is dorsiflexed, which transfers the bending force to
the distal radius. With this mechanism, the distal fragment is usually
displaced dorsally.
In a physeal injury, the
periosteum is usually intact on the same side to which the epiphyseal fragment
is displaced (ie, compression side), and can be used to help stabilize the
fracture after it is reduced. On the opposite, or tension side, the thicker
periosteum remains attached to the perichondral ring and ruptures proximally in
its thinner metaphyseal area. This wad of periosteum can become interposed in
the fracture site and can subsequently interfere with the reduction.
Documentation of the
neurovascular function is important in children's distal radial metaphyseal and
physeal injuries. Nerve injuries are most often neurapraxias of the median or
ulnar nerve that result from stretch at the time of acute deformation, and only
rarely is a major nerve trapped between the ends of the fractured bone. Nerve
paralysis with a peculiar springy sensation noted during attempts to reduce the
fracture may be the only indication of nerve entrapment within the fracture.
Closed reduction is usually
easy unless the ulna is intact and the radius is completely displaced.
Overreduction is rarely a problem because of the intact dorsal periosteum.
Repeat manipulation of distal radial physeal injuries is not recommended
because of the increased risk of growth disturbance. If the patient presents
for treatment later than 3 days after the injury, primary manipulation of the
fracture is not advisable, as forceful attempts are likely to damage the physis
and result in growth arrest. General anesthesia may be required to provide
adequate sedation in the event that late reduction must be performed.
Because the results with
nonoperative management are so good, there are primarily only five specific
indications for operative intervention: the need for percutaneous pin fixation
because of severe local soft-tissue injury or proximal ipsilateral fractures;
failure to achieve an adequate reduction by closed methods; open fractures;
comminuted intra-epiphyseal fractures; and carpal tunnel compression or
compartment syndrome
If severe soft-tissue injury
accompanies the bony injury, as with a crushing injury or superficial
abrasions, rigid external immobilization with a cast may not be adequate and
could even compromise the circulation. In these cases, the surgeon can
stabilize the fracture with a single pin placed percutaneously across the
fracture site. Once the distal fragment is internally stabilized, the surgeon
can place a loose-fitting cast, mainly for protection. The most common use for
percutaneous pins is with ipsilateral supracondylar humeral fractures
A prompt reduction under
adequate relaxation is important in the closed management of these fractures.
If a significant delay in reduction occurs, a fibrous clot usually develops at
the fracture site and may decrease the ease of reduction; the fracture may
require a more forceful manipulation to obtain an adequate reduction. The more
force applied across the fracture site, the greater the chance of injuring the
proliferating cells of the physis; therefore, one should try to obtain a prompt
reduction as gently as possible. During reduction, the surgeon should maintain
traction across the fracture site to separate the fracture fragments and,
theoretically, to decrease the shear forces on the physis with manipulation.
The use of finger-traps with counter traction applied across the anterior
portion of the flexed elbow can assist in maintaining traction during
reduction. With traction applied, the surgeon can often easily reduce the
fracture by simply pushing the distal fragment anteriorly and distally with the
thumb
Immobilization for 4 weeks
is typically adequate. Use of a volar splint for another 10 to 14 days provides
comfort and protection from reinjury until the forearm muscle strength and
wrist motion have begun to return to prefracture status.
Diligent follow-up is
essential. X-rays at 4 to 6 months after the injury can help to ensure that
normal growth has resumed. Symmetric migration proximally of the Harris-Park
growth lines is a manifestation of normal growth. All fractures should be
followed, because even the most benign-appearing ones may result in growth
arrest.
Distal radial physeal
fractures are usually Salter-Harris type II Injuries, and can be treated
similarly to distal radial metaphyseal injuries. It is important, however, to
stress to the parents the increased likelihood of physeal growth arrest, and
follow these injuries appropriately so as to catch any growth arrest as early
as possible.
The two factors most
directly related to this growth arrest are, the energy of the initial trauma,
and iatrogenic injury with late reduction. To avoid being part of the problem,
rather than the solution to it, one should avoid repeat reduction (closed or
open) after 7 days from the time of the injury. If necessary, dorsal (as
usually the deformity is apex volar) opening wedge osteotomy can be performed
in the skeletally mature patient to alleviate the complications of malunion.
Hand
Several factors combine to
make the pediatric hand vulnerable to injury. Among these are the usage pattern
of this relatively exposed appendage and the child's curiosity about the
surrounding world. It should therefore come as no surprise that injuries of the
hand and wrist are among the most common in the skeletally immature population.
The prevalence of these
injuries increases sharply after the eighth year. This may be due to the
changing balance between injury-resistant cartilage and bone in the maturing
hand, and the fact that children participate more aggressively in contact
sports around this age.
There is disagreement about
which is the most common fracture in the child's hand. Some authors cite the
distal phalanx crush injury as the most frequent, others recognize the
Salter-Harris (S-H) II fracture of the proximal phalanx base. Fractures of the phalanges outnumber
metacarpal fractures. The right and left hands are equally affected by skeletal
trauma. The border digits (the index and small fingers) are usually the most
commonly injured rays. More boys than girls present with hand fractures.
Hand injuries involving the
growth plate are less common than extraphyseal fractures, and reports vary
between 10% and 40% in the reported series. Salter Harris II fractures
predominate in all reports.
Most metacarpal and phalangeal
injuries of the pediatric hand are non-displaced, and can be treated non-operatively.
It is very important to respect the hand’s propensity for stiffening up in
the position in which it is immobilized. Hand injuries should always be splinted
in a position of function to protect against re-injury and debilitating stiffness
often found when fingers are immobilized in a fully extended position. One
of my earliest mentors used to say that the finger immobilized in extension
on a tongue depressor is only good for one thing, “so the kid could point
straight at you in court and say, ‘that’s the jerk who did this to
me.’”
