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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_574_Библиотеки_им_академика_М_И_Перельмана.pdf
articular platform in space, with appropriate volar tilt and
radial inclination, ( iii)promote adequate healing, ( iv)ensure
astable and reduced DRUJ, and ( v )tomaintain adequate
finger and elbow ROM. It also must be remembered that
the distal radius has two chondral surfaces that must be
aligned: the radiocarpal joint with the scaphoid and lunate
facets,and thesigmoid notchthat articulates with the
distal ulna.
External fixator frames function by inducing ligamentotaxisacrossthe fracture site andtherebyreducing fracture
fragments. Distraction alone can maintain length, neutralize
forces,and reduce largerperipheralfracturefragments.
However,external fixation alone is often ineffective in reducing
impactedcentral articular fragments. Flexionalone cannot
restorevolar tilt, as the dorsal capsular ligaments are more
expansile than the volar ligaments. Indeed, excessive flexion
FIGURE 1 The proximal fixator pins are placed through one open incision. The pins
are placed betweenthe tendons of the radial wrist extensors. The superficial radial
nerve can be seen volar to this interval. Source:Courtesy of John T. Capo, MD.
FIGURE2 Half pins with a2.5-mm thread diameter areplacedinthe second
metacarpal. The proximal pin is placed at the metaphyseal flare and the distal pin is
placed in the shaft. Source:Courtesy of John T. Capo, MD.
134
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Capo et al.
and ulnar deviation can cause acute carpal tunnel syndrome
and make postoperative rehabilitation difficult, as this position
severely limits finger ROM.
&
Operative Technique
Proximal threaded half pins, 3.0 to 4.0 mm, are placed approximately one hand’s breadthproximal to the radial styloid, in a
relatively uncovered area of the radial shaft. This area is largely
devoid of tendons and is just proximal to the muscles of the first
and thirdcompartments (the extensor pollicis longus, extensor
pollicis brevis,and abductor pollicis longus). Asingle 2- to 3-cm
incision should be used for both proximal pins, and care taken
to identify and protect the tendons and the superficial branch of
the radial nerve. Percutaneous incisions should be avoided as
this places these structures at risk. The extensor carpi radialis
longus (ECRL) and extensor carpi radialis brevis interval is
FIGURE 3 Placement of proximal and distal half pins in a45 8
dorsal–radial plane. Source:Courtesy of John T. Capo, MD.
FIGURE 4 Excessive wrist flexion is inappropriately placed in
this distal radius fracture case. The wrist should be placed in
neutral alignmenttopromotefinger ROMand rehabilitation.
Abbreviation:ROM, range of motion. Source:Courtesy of John
T. Capo, MD.
Augmented External Fixation for Distal Radius Fractures
&
135
utilized. This is slightly more dorsal than the brachioradialis–
ECRL interval, and thus lies further away from the superficial
branch of the radial nerve. Also this interval provides atendon
buffer on either side of thepinsand provokes less nerve
irritation (Fig. 1). The wrist extensors are immobilized by the
frame and thus there is little tendon excursion in this interval.
Distal pins placed in the hand should have asmaller
thread diameter (2.5 mm) to help avoid fracturing the metacarpal. These are placed in the proximal metaphyseal flare
andshaftofthe second metacarpal(Fig. 2).Openpin
placement is again used to avoid injuring the first dorsal
interosseous muscle and terminal branches of the superficial
radial nerve. In addition, pins should not be transfixed into
the thirdmetacarpal as this may damage the motor branch of
the ulnar nerve. Both sets of pins should be bicortical and
placed 458 in the radial–dorsal plane. Placing the frame in this
plane allows full retropulsion of thethumb andaids in
achieving unobstructed lateral Xrays (Fig. 3).
Next, all the skin incisions at the pin sites are closed with
nylon sutures. This is easier nowthan at the close of the
procedurewhere spanningbarsand otherexposed
hardware make closure tedious. The pinclampsare next
placed on the half pins at an appropriate level and tightened.
The fracture must next be reduced. It is tempting to apply
excessive volar flexion and ulnar deviation in an attempt to
reduce the fracture deformity (Fig. 4). However,this extreme
degree of positioning does not effectively induce flexion of the
distal fragment andmay result in elevatedcarpaltunnel
pressures (6,7). It is more effectivetoinducetractionand
palmar translation of the carpus. In addition, ulnar deviation
(A) (B)
FIGURE 5 ( A )APview of distal radius fracture treated with augmented external fixation. The carpus is reduced on the distal radius
and there is no over-distractionatthe radiocarpalormidcarpal joints. ( B )Lateral view of another distal radius fracture showing
neutral alignment of the wrist and hand. Abbreviation:AP, anterior–posterior. Source:Courtesy of John T. Capo, MD.
FIGURE 6 Over-distraction of the carpus in this distal radius fracture
demonstrates distal translation of thescaphoid whichindicates an
associated scapho-lunate ligament tear. Source:Courtesy of John T.
Capo, MD.
136
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Capo et al.
should not exceed 208 ,asthis may place excessive strain on the
triangular fibrocartilage complex.
Distal radius fractures oftenrequire additional fixation
methods after placement of the external fixator.The addition
of Kirschner (K)-wires to an external fixation construct has been
proven in the lab to have significantly increased rigidity (8).
This may be required if fracturereduction cannot be obtained by
ligamentotaxis alone, or if an excessive, nonphysiologic position
of the wrist is needed for fracture reduction. In this latter case,
the fixator can be utilized as aprovisional reduction tool. Often
the fracture requires hyperflexion, ulnar deviation, and significant palmar translation. After this is achieved the reduction
can be held with crossed K-wires(0.062
00
,0.05400,or0.04500), one
or two placed in the radial styloid and an additional pin placed
in the ulnar corner of the radius. This configuration with 0.062
00
K-wires has been shown to provide optimal rigidity (9). The
radial-sided pins pass from straight radial to ulnar or slightly
volar to dorsal, while the ulnar corner pin is placed obliquely
from dorsal to volar.The radial styloid pins should be placed
through asmall open incision while the dorsal ulnar pins can be
placed percutaneously.Once the pins are placed, the external
fixator is adjusted back to amoreneutral andphysiologic
alignment (Fig. 5). Supplemental K-wires may also be utilized
as reduction joysticks to move articular fragments into anatomic
position prior to final pin positioning.
At the close of the procedure, the position of the wrist and
degree of distractionmustbecritically assessed. Flexion
should not be more than 108 as this prevents power grip of
the handand caninducemediannerve compression.Full
passive flexion of the fingers into the palm should be easily
achieved. If this is impossible or has significant rebound then
the distractionisexcessiveand needs to be reduced.This
inhibitionofpassive flexion is caused by tensiononthe
external finger extensors and will seriously jeopardize final
finger ROM. Examination of the final fluoroscopy shot should
show even distraction across all the carpal joints. There should
be equal distraction seen at the midcarpal and radiocarpal
joints. Excessive distraction can be displayed as distraction of
(A)
(C)
(B)
(D)
FIGURE 7 ( A )APand ( B )lateral views of an open, severelycomminuted and displaced distal radius
fracture. ( C )APand ( D )lateral Xrays showing initial stabilization of an external fixator. The distal most
proximal pin is near the fracture site which may interfere with future plate placement. Abbreviations:AP,
anterior–posterior. Source:Courtesy of John T. Capo, MD.
Augmented External Fixation for Distal Radius Fractures
&
137
the scaphoid in relation to the lunate, signifying ascapholunate tear (Fig. 6). In both the AP and lateral views, the carpus
should be concentrically reduced, with thelunate and
scaphoid in there respective fossa.
&
COMBINED ORIF TECHNIQUES
An external fixator can be used as one of several components
in the fracture fixation hardware of adistal radius fracture.
This is ideal forseverehigh-energy fracturesthat have
metaphyseal and articular comminution. The external fixator
is used to neutralize the metaphyseal fragmentation while
smallplatesorpercutaneouslyplaced wiresare used to
alignand fix thearticular fragments. Ideally,the fixator
should be placed in the standard 458 dorsal–radial position.
This orientation allows access for either adorsal, volar,or
radial approach. Initially,excessive traction and angulation
can be applied to help align fragments provisionally.Alarge
radial styloid fragment may be approached by avolar Henry
approach or astraight lateral approach. Lunate facet fragmentscan be addressedthrough avolar–ulnar approach
betweenthe ulnar neurovascularbundle and thecarpal
tunnel contents, or dorsally throughthe thirdorfourth
dorsalcompartments. First, thearticular fragmentsare
secured, then the articular segment is attached to the shaft.
At this point, the fixator can be backed offtoaphysiologic
position, while still maintaining mild distraction to unload the
(A)
(B)
(C)
(D)
FIGURE 8 ( A )Intra-operative AP and ( B )lateral Xrays demonstrating restoration of the joint surface with asmall
volar plate and additional percutaneous wires placed in the styloid. ( C , D )Radiographs at follow-up showing
healing of the fracture, reduction of the carpus, and articular congruity at the distal radius. Abbreviations :AP,
anterior–posterior. Source:Courtesy of John T. Capo, MD.
138
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Capo et al.
carpus from the distal radius (Figs. 7and 8). The fixator can
be removed at four to five weeks for early wrist ROM with the
other hardwareproviding adequate stability.
&
STABLIZATION OF DRUJ
The stability of the DRUJ should be evaluated at the close of
operative fixation of all wrist injuries. DRUJ instability injury
occurs in up to 10% of patients with distal radius fractures and
is amajor source of disability following successful healing of
these fractures (10). The DRUJ is assessed with the elbow placed
on the hand table and flexed at 908 .The radius and hand are
stabilized and the ulna is stressed volarly and dorsally.This
maneuver is done in neutral rotation and again in full pronation
and supination. If there is abnormal translation or asignificant
click or sense of subluxation, the DRUJ must be stabilized. If the
DRUJ can easily be reduced it can be stabilized in several ways.
It can be fixed with percutaneous ulnoradial pins (Fig. 9) or by
inclusion of the ulna in the external fixator construct with an
extension bar (Fig. 10). Alargeassociated ulnar styloid can be
fixed with ascrew or tension band technique. If radioulnar
instability is not treated at initial injury,chronic subluxations
ensuesand usuallyrequiresopenreductionand ligament
reconstruction for treatment (10).
&
AFTERCARE
Pin track irritation and infection may occur.The importance of
dailypin care must be reinforcedtopatients. Caregivers
responsible forelderlyorinfirmed patientsmustalso
understand the importance of compliance with pin care. After
the first post-op dressing change, twice daily cleaning with onehalfstrengthhydrogenperoxideisinitiated.Daily ROM
exercises are also important. Occupational therapy is used in
approximatelytwo-thirdsofour patients.The decision for
therapy is usually made in the first two weeks after fixation.
External fixation across the wrist should allow for complete
finger ROM. Digital stiffness must be avoided as this is very
difficult to treat chronically.Elbow flexion and extension and
limited forearm rotation should also be initiated if there is no
associatedinstabilityofthe elboworDRUJ(Fig. 11). The
functional goal is to have complete digital and elbow ROM at
the time of fixator removal.
Augmentedfixationcan alsobebeneficial during the
postoperative course. With thepresenceofdualfixation,
either the fixator or K-wires can be removed earlier if they
become problematic.Thiscan be especially helpfulinthe
presence of apin tract infection or in order to initiate early
ROM therapy.
&
COMPLICATIONS
The complication rate associated with external fixation of distal
radius fractures can be quite high, ranging from 20% to 85%
(11–15). Themajorityofcomplications areminor pintrack
infections and transient neuropraxias. Wrist stiffness is often
associated with external fixation, but usually is afunction of the
injury and not the fixator.However,more serious complications
canoccur. Theseprimarily consist of tendon irritation and
rupture, loss of fracture reduction, andcomplex regional
pain–like syndromes (CRPS).
Most superficial pin track infections can be treated with
meticulous pin care and oral antibiotics. However,occasionally pintract infections requiredebridement or pin
removal. In such cases, the presence of augmentation such
as K-wirescan be very valuable formaintaining the
reduction. The rate of pin track infections, both superficial
and deep, is about 20% (11,15,16). Some have advocated
delaying surgery 7to10days prior to pin placement to
allow swelling to subside and potentially decrease the rate of
pin tract infections (4).
(A)
(C)
(B)
FIGURE 9 ( A )Lateral postoperative Xray of distal radius stabilized with an external fixator demonstrating dorsal subluxations of the ulna. The
patient had aprominent distal ulna and difficulty with forearm rotation. ( B )APXray showing two 0.062
00
K-wires holding the reduced DRUJ. ( C )
Lateral view demonstrating reduction of DRUJ. Abbreviations:AP, anterior–posterior; DRUJ, distal radial–ulnar joint; K-wires,Kirschner wires.
Source:Courtesy of John T. Capo, MD.
Augmented External Fixation for Distal Radius Fractures
&
139
Ratesofneuritisand CRPS of 10%to22% havebeen
reported (11,12,14).Itisunclear if thesenerve injuries are
from the initial trauma, or acomplication of the treatment. It
seems the incidence of nerve irritation may be significant (14)
butthe occurrence of atrue CRPS is rare.Openhalf pin
placementishelpful in minimizing iatrogenicnerve injury.
Kaempffe and Walker (17) have suggested acausal relationship
between fixatorcarpaldistraction andpostoperative ROM
deficits. This often quoted study,however,did not demonstrate
astatistically significant effect of distraction on outcome. Only
duration of external fixation was statistically correlated with
decreased wrist ROM.
We have analyzed 21 patients, two years after external
fixation for moderate and severe distal radius fractures. The
clinical results demonstrated 10 excellent, 7good, 4fair,and no
poor outcomes according to the Gartland and Werley classification. Grip strength averaged 83% of the contralateral side,
and ROM showed flexion of 628 ,extension of 568 ,and a1548 arc
of rotation.The amountofdistraction,asmeasured by the
carpal height index was assessed and related to final clinical
outcome. We found no adverse effects on wrist flexion extension
or rotation with fixator distraction. It appears that stiffness in
injuries treatedbyexternal fixation is more afunction of the
injury rather than the distraction induced by the fixator.
&
OUTCOMES
The biomechanics of augmented external fixation has been
studied by Wo lfe (8). These authors compared osteotomized
distal radii stabilizedwith an external fixator aloneor
combined with various K-wire configurations. Both standard
fracture transfixion wirescombined with an external fixator,
and afixator with and an “outrigger” wire placed into the
distal fragment andsecured to theexternalfixatorwere
superior to external fixation alone in reducing fracture
motion. Asingle wireacross the fracture site was enough to
gain appreciable stability, and additionalwires didnot
improve stability further.
(A) (B)
(C)
(D)
FIGURE 10 ( A )APand ( B )lateral view of acomminuted distal radius fracture. ( C )Postoperative Xray showing
stabilization of fracture with volar plating, dorsal pin fixation, and an externalfixator. ( D )The external fixator constructis
extended to the ulnar shaft with an outrigger bar to stabilize the DRUJ. Abbreviations:AP, anterior–posterior; DRUJ, distal
radial–ulnar joint. Source:Courtesy of John T. Capo, MD.
140
&
Capo et al.
Dunning et al. (18) studied augmented external fixation in
distal radius fracturesbygeneratingsimulatedfinger and
forearmmotions in cadavers. The extremetieswerestabilized
using spanningexternal fixation with or withoutradial
styloid pins, or with adorsal distal radius plate. The results
demonstrated that supplemental K-wires significantly reduce
fracture fragment motion when compared with external
fixation alone. The stability imparted by the augmented ex-fix
construct approached that reachedwith the dorsal plating
technique.
Harleyetal. (14) performedaprospective randomized
study comparing augmented external fixation versus casting
combined with percutaneous pinning for unstable distal radius
fractures.Forty-one patients were followed forsix months.
The authors noted no difference in clinical outcome between
the two groups, although they did note percutaneous pins and
casting weremorelikely to result in articular gaps and defects.
There was also adefinite trend towardmore frequent pin tract
infections,CRPS, andnerve injuries in theexternalfixator
group. The external fixator grouphad no significant difference
in postoperative ROM.
Werber et al. (12) performed arandomized, prospective
study comparing external fixation of distal radius fractures
using the standard four-pin technique to afive-pin external
fixator that included an additional pin placed in the radial
styloidand attached to thefixator.Fifty patients were
evaluated at least six months postoperatively.The authors
found that thefive-pinfixatorwas significantly better at
(A)
(B)
FIGURE 11 ( A )Clinical photograph demonstrating full elbow extension and ( B )flexion of patient with adistal radius
fracture treated with an external fixator. Source:Courtesy of John T. Capo, MD.
Augmented External Fixation for Distal Radius Fractures
&
141
reduction of the fracture and in maintenance of the anatomic
parameters. Therewas no differenceinarticular step-off
between the groups. The five-pin group had abetter clinical
outcome with better ROM, and grip strength when compared
with the four-pin group.
&
SUMMARY
Distal radius fractures are ubiquitous and are seen in all age
groups from children to the elderly.Today,the choice of options
for surgical treatment of distal radius fractures is wide ranging.
With the popularity of locked plating, typically through avolar
approach,the external fixator is nowusedlessfrequently.
However with theadventofnewer lowprofile designsin
combinationwith supplementary pins,screws, or small
plates, theutility of external fixatorshas increased.
The principles of anatomic articular reduction, minimal softtissue trauma,and earlyROM must be strictly adhered to
ensure optimal results (19).
&
SUMMATION POINTS
Indications
&
Extra-articular distal radius fractureswithsignificant
displacement.
&
Intra-articular fractures with large fragments that can be
reduced with percutaneous or limited open means.
&
Open fractureswith complexopenwoundsand softtissue injury.
Complications
&
Pin sight irritation and infection.
&
Inadequate reduction of articular surface.
&
Over-distraction resultingindigital stiffness and median
nerve irritation.
Outcomes
&
Stable fixation with early return to function.
&
Limited soft-tissue injury with surgery.
&
Excellent and good results in O 85% of patients.
&
REFERENCES
1. Alffram PA,G’doran CHB. Epidemiology of fractures of the
forearm. JBone Joint Surg 1962; 44A:105–14.
2. Cohen MS, McMurtry RY,Jupiter JB. Fractures of the distal radius.
In: Browner BD, Jupiter JB, Levine AM, Tr afton PG ,eds. Skeletal
Trauma: Basic Science, Management and Reconstruction., Vo l. 2.
Philadelphia,PA: WB Saunders, 2003:1315–61.
3. Edwards GS. Intra-articular fractures of the distal part of the radius
treated with asmall AO external fixator.JBone Joint Surg 1991;
73A(8):1241–50.
4. Zanotti RM, Louis DS. Intra-articular fractures of the distal end of
the radius treated with an adjustable fixator system. JHand Surg
1997; 22A(3):428–40.
5. Capo JT,Accousti K. The Effect of Rotational Malalignment on
Radiographs of the Wr ist. Scientific Presentation, ASSH Annual
Meeting, 2002.
6. Gausepohl T, Pennig D, Mader K. Principles of external fixation
and supplementary techniquesindistal radius fractures. Injury
2000; 31(1):56–70.
7. Bartosh RA, Saldana MJ. Intra-articular fractures of the distal
radius: acadavericstudy to determine if ligamentotaxis restores
radiopalmar tilt. JHand Surg1990; 15A:18–21.
8. Wolfe SW,Swigart CR, Grauer J. Augmented external fixation of
distal radius fractures: abiomechanicalanalysis. JHand Surg1998;
23A(1):127–34.
9. Naidu SH, Capo JT,Ciccone W. Percutaneous pin fixation of distal
radius fractures: abiomechanical study.JHand Surg 1997;
22A(2):252–7.
10. Geissler WB ,Fernandez DL, Lamey DM. Distal radioulnar joint
injuries associated with fractures of the distal radius. Clin Orthop
1996; 327:135–46.
11.Cannegieter DM, Juttmann JW.Cancellous grafting and external
fixation for unstable Colles’ fractures. JBone Joint Surg1997;
79B(3):428–32.
12. McQueen MM. Redisplaced unstable fractures of the distal
radius: arandomized, prospective study of bridging versus
non-bridging external fixation. JBone Joint Surg 1998;
80B(4):665–9.
13. Tapio F, Jukka R, Pekka H, et al. Nonbridging external fixation in
the treatment of unstablefractures of the distal forearm. Arch
Orthop Trauma Surg 2003; 123:349–52.
14. Harley BJ, Scharfenberger A, BeaupreLA, et al. Augmented
external fixation versus percutaneous pinning and casting for
unstable fractures of the distal radius—a prospective randomized
trial. JHand Surg2004; 29(5):815–24.
15. Sanders RA, Keppel FL ,Waldrop JI. External fixation of distal
radial fractures: resultsand complications. JHand Surg 1991;
16A(3):385–91.
16. McQueen MM, Michie M, Court-Brown CM. Hand and wrist
function after external fixation of unstable distal radial fractures.
Clin Orthop 1992; 285:200–4.
17. Kaempffe FA,Walker KM. External fixation for distal radius
fractures: effect of distraction on outcome. Clin Orthop 2000;
380:220–5.
18. Dunning CE, Lindsay CS, Bicknell RT,etal. Supplemental pinning
improves the stability of external fixation in distal radius
fractures during simulated forearm motion. JHand Surg 1999;
24A(5):992–1000.
19. Behrens FF.General theory and principles of external fixation. Clin
Orthop 1989; 241:15–23.
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Capo et al.
18
Non-Bridging External Fixation of the Distal Radius
Margaret M. McQueen
Royal Infirmary of Edinburgh,Edinburgh, Scotland, U.K.
&
INTRODUCTION
Distal radius fractures are extremely common injuries occurring
mostly as low-energyextra-articular or minimal articular fractures in middle-aged to elderly women but with asmall peak of
incidence also in young men with higher energy injuries that
tend to be intra-articular (1).
Most stable distal radial fractures can be treated in acast.
Instability of the distal radius, defined as either demonstrated
or predicted inability to retain the reduced radiological position
in acast or articular displacement, are considered indications
for surgical treatment of distal radial fractures in independent
patients regardless of age. Anumber of surgical techniques are
possibleinthissituation, includingnonbridgingexternal
fixation. This method employs pins in the distal fragment and
radius proximal to the fracture, thus not bridging either the
radiocarpal, intercarpal, or carpometacarpal joints.
The first recorded use of external fixation in the wrist was
reported by Ombre´danne who used anonbridging technique
for fractures and osteotomies of the forearm in children in 1929.
Ombre´danne concluded that “temporary osteosynthesis with
external connection allows amathematical adjustment of the
surgical correction . and guarantees further retention with
ample and sufficient precision” (2).
For about 60 years, this sensible conclusion was largely
ignoredwithsurgeons concentrating on bridging external
fixation first introduced by Anderson and O’Neil in 1944 (3).
At that time, external fixation was generally used for severely
comminuted intra-articularfractures of thedistalradiusin
young men in whom nonbridging external fixation may not
have been an option. Interest in the technique did not revive
untilthe 1990s,possiblybecauseofincreasing numbersof
healthier,elderlypatients with low-energy fractures, who
unlike previous generations, were notpreparedtoaccept
malunion and possible functional deficit and in whom nonbridging external fixation was afeasible option.
&
INDICATIONS
It is now generally agreed that malunion of afracture of the
distal radius, whether metaphyseal or intra-articular,islikely to
lead to functional deficit leading to difficulty with the normal
activities of daily living (4–7). Metaphyseal instability of the
distal radius, whetherdemonstrated or predicted, in the fit
patientisthe most commonindicationfor treatment with
nonbridging external fixation to prevent malunion. Nonbridging external fixation should be used in preference to bridging
external fixation whenever possible because of the improved
radiological and functional results that have been demonstrated
(8–10).
Nonbridging techniques are indicated for extra-articular
dorsally displaced fractures with metaphyseal instability.The
technique is not suitable for the treatment of volar displaced
fractures.Mostunstablefractures of thedistalradiuswith
minimal or undisplaced articular extension can also be successfully treated using this technique. Fewer cases with displaced
articular extensions are suitable for nonbridging ex fix as after
fixation of the joint surface they may lack the necessary space in
the distal fragment for the distal pins. However,the use of
multiplanar wires both to reduce and hold the articular fragments and to hold the metaphyseal alignment in ahybrid-type
construct of nonbridging external fixation was recently reported
as agood treatment option for articular fractures (11). Nonbridging external fixation is also indicated as aminimally invasive
technique for corrective osteotomy of the distal radius for the
treatment of symptomatic malunion.
The main contraindications for the technique of nonbridging external fixation is lack of space for pins in the distal
fragment: approximately1cm of intact volar cortex is required
to allow purchase for the pins. Dorsal comminution is not a
contraindication for the technique as the pins achieve their grip
on thevolar cortex butsevere articular comminutionmay
preclude pin placement in the distal fragment.
As in any other technique for the management of unstable
distal radius fracture, nonbridgingexternalfixation is not
recommended forthe frail elderlydependent patient.With
such patients, the fracture should be managed in acast and
malunion accepted (12). However,osteoporosis in the fit patient
is not acontraindication as fixation failure is rare(8,11,13,14). As
with any external fixation technique, insertion of pins through
areas of possible skin infection is also contraindicated.
The indications for nonbridging external fixation of the
distal radius do not differ significantly from the indications for
the comparable open technique of either dorsal or volar plating.
However,platingtechniques frequentlyrequireasecond
operation for implant removal, which may be arelative contraindication in patients with significant comorbidities.
&
CONSIDERATIONS FOR PREOPERATIVE
PLANNING
The technique of nonbridging external fixation for fracture of
the distal radius is simple and requires minimal preoperative
planning. Physical examination should include assessment of
neurological function in the hand, since in the presence of carpal
tunnel syndromedecompressionshouldbeaddedtothe
surgicalprocedure.Evidenceofcomplex regional pain
syndrome type Ishould be noted but is not acontraindication
for the technique. Examination of the skin in the area is required
to exclude local infection.
The mainstay of preoperative imaging is agood series of
preoperative films with true anteroposterior (AP) and lateral
views of the wrist. This should allow assessment of the size of
the distal fragment. On the lateral view,the volar cortex should
be seen clearly: 1cmofintact volar cortex is required. The AP
view also allows assessment of the size of the fragment. Beware
of the distal fragment that narrows towardthe distal radioulnar