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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_574_Библиотеки_им_академика_М_И_Перельмана.pdf
joint on the AP view forming atriangle with the radial styloid at
its apex. This configuration may not allow sufficient purchase
for an ulnar-sided pin.
Unless thefracturehas redisplaced afterinitialclosed
reduction, the likelihood of instability should also be assessed
on the preoperative plain films to establish the indication for
stabilization.Radiologicalfactors increasing theriskof
instability arethe presence of metaphysealcomminution,
increasing radial shortening, and increasing initial dorsal angulation (15).
No special preoperative planning is required for the use of
nonbridging external fixation in distal radial osteotomy.Inthis
situation, the size of the distal fragment is determined by the
placement of the osteotomy cut. The desiredangle of correction
may be estimated preoperatively but can easily be adjusted peroperatively by using the pins as ajoystick. Moreadvanced
imaging is not usually necessary unless the nonbridging technique is to be used for severe articular fractures when computed
tomography scanning may be required to visualize the articular
fracture pattern and to plan placement of hybrid-type pins.
&
SURGICAL TECHNIQUE
Axillary or supraclavicular regional block is recommended as
there is some evidence that the use of this technique will reduce
the incidence of complex regional pain syndrome type I(16).
The patient is placed supine with the affected arm extended on
the hand table and the wrist in neutral rotation. Atourniquet is
applied to the upper arm. The surgeon is seated on the cephalic
side of thearm table andthe C-armispositionedonthe
opposite side. Fracture reduction prior to insertion of the pins
is not necessary.
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Acute Fractures
The distal pins are inserted first from dorsal to volar,midway
between the fracturesite and the radiocarpal joint, and on either
side of Lister ’s tubercle. If there is an undisplaced sagittal,
articular fracture pins should be placed on both the radial and
ulnar sides of the articular extension. Lister’s tubercle may be
palpable in caseswith minimal swelling andgives agood
indicationofthe approximatelevel of pinentry.The exact
placing will be determined by the type of fixator used, but in
those with two parallel distal pins, the ulnar-sided pin should
be inserted first into the ulnar corner of the distal radius. A
marker is placed on the skin and its position in relation to the
entry point on bone confirmed on alateral and AP view of the
wrist (Figs. 1and 2). A1-cm longitudinal incision is made at this
point and the extensor retinaculum visualized. Alongitudinal
incision is made in the retinaculum under direct vision with
care takennot to damage anyunderlying te ndons.The
FIGURE 1 An anteroposterior view of the distal radius
showing theideal placementofafixator pininthe ulnar
corner of the distal radius. The patient had aconcomitant
scaphoid fracture fixed with ascrew.
144
&
McQueen
underlying bone is then exposed. Afixator pin is placed on the
bone and the position confirmed on the image intensifier.The
pin is then adjusted so that its projected course is parallel to the
radiocarpal joint on the lateral view.The pin is then inserted by
hand until its tip penetrates the volar cortex (Fig. 3). Predrilling
is not necessary.Further pins may then be inserted using the
same technique; the spacing and relationship of the pins will be
determined by the fixator used.
Pins are then placed in the radial diaphysis proximal to the
fracture. These should be as close as possible to the fracture to
allowassmallafixator construct as possible. Openpin
placement is mandatory to avoid damage to the dorsal branch
of the radial nerve. Alongitudinal skin incision is used over the
dorsum of the radius followed by blunt dissection to expose the
tendons of extensor carpi radialis longus and extensor carpi
radialis brevis.The natural interval between these tendons is
developed to expose the radius. The proximal pins are then
inserted by hand with or without predrilling and should engage
both cortices of the radius. The fixator should then be assembled
but not tightened. Reduction of the fracture is then achieved
using the distal pins as “joysticks” (Fig. 4). In afresh fracture,
this requires verylittle force. Wherereduc tionhas been
delayed, forcible reduction should not be attempted as this
may causepin loosening. In latecases,gradual reduction
shouldbeemployedand is usuallypossibleuptoaround
three weeks after fracture. Should reduction not be possible
without undue force asmall incision should be made over
the dorsum of the fracture and alever inserted to reduce the
fracture by direct means. The fixator is then tightened and the
reduction confirmed using the image intensifier.
&
Distal Radial Osteotomies
Use of anonbridging external fixator for distal radial osteotomy
allows minimal soft tissue dissection. A2.5-cm transverse skin
incision is made over thesite of deformity.The extensor
retinaculumisthendividedlongitudinally and theradius
exposed between the thirdand fourth extensor compartments.
The level of the osteotomy is identified. Distal pins are then
inserted through two separate incisions using the same technique as described for acute fractures and are placed between
the level of the planned osteotomy site and the radiocarpal joint.
An osteotomy cut is then made with asmall saw parallel to the
pins and as farasbut notthrough thevolar cortex. An
osteotome is then inserted into theosteotomy cut andthe
volar cortex cracked by creating an open wedge dorsally.
Proximal pin insertion is performed using the same technique as for acute fractures. The distal pins can then be used to
allow accurate positioning of the distal fragment. The wedgeshaped defect in the distal radius is filled with cancellous bone
FIGURE 2 Alateral view of the distal radius demonstrating the
starting point for afixator pin, midway between the fracture and the
joint.
Non-Bridging ExternalFixation of the Distal Radius
&
145
harvested from the iliac crest (Fig. 5). The transverse incision is
closed but the pin track incisions are left open.
Postoperative management is the same for both fractures
and osteotomies. Pin tracks are not closed but are treated with
dressings that are initially changed daily,but then twice weekly,
provided the pin tracks are satisfactory.Hand and wrist movements are encouraged and no form of immobilization is used.
The fixator is removed in the majority of cases at five to six
weeks. Occasionally,inthe presence of associated diaphyseal
comminution,alongerperiodisrequireduntil diaphyseal
healing is evident radiologically.
&
COMPLICATIONS
There are few perioperative pitfalls. One which may be encounteredper-operatively is over-reduction of the fracture (Fig. 6),
especially if there is bayoneting of the volar cortex. This should
be easily recognizedonthe imageintensifierviews andis
therefore apreventable complication. If insertion of distal pins
proves unsuccessful because of insufficient intact volar cortex,
then it is simple to convert the construct to abridging construct
with or without augmentation.
Aseptic pintrack looseningorpullout is rare even in
osteoporotic bone. However,the most common complication
of nonbridging external fixation of the distal radius is pin track
infection, which is reportedtooccur in 9% to 33% of cases
(8,11,13,14,17). Fortunately,the vast majority are minor infections that are treated with antibiotics and increased frequency
of dressings.
Extensor pollicis longus rupture or irritation occurs in less
than 5% of cases (8,11,13,18). This is asimilar rate to distal radial
fractures treated by different methods (1), but much less than
the more invasive technique of dorsal plating in which high
ratesofextensor tendonrupture or irritation arereported
(19,20). Rates of other fracture-related complications are not
affected by the use of nonbridging external fixation.
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OUTCOMES
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Fractures
Radiologicaloutcomesofnonbridging external fixationfor
extra-articularorminimal articularfractures areuniformly
good (Table 1). The first report of nonbridging external fixation
with anatomical results was acomparison of plaster versus
nonbridging external fixation in patients under 60 years of age
with displaced distal radial fractures. Thequality of the
reduction was good in both groups, but the reduced position
FIGURE 3 The pin has been inserted by hand. Note that the pin
penetrates the volar cortex.
146
&
McQueen
(A)
(B)
FIGURE 4 ( A )Two pins have been inserted. The fracture is unreduced.
( B )The fracture has been reduced using the joystick technique.
(A)
(B)
FIGURE 5 Apostoperative anteroposterior ( A )and lateral ( B )view
following corrective osteotomy of the distal radius using nonbridging
external fixation. Note the bone graft in the defect which is clearly seen on
the lateral view.
Non-Bridging ExternalFixation of the Distal Radius
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147
wasmaintainedbetter(p ! 0.01) by theexternalfixation
group(21).
The first randomized studyofnonbridgingexternal
fixation wasacomparison with bridging external fixation.
Sixty patients with redisplaced distal radial fracturesand an
average age of 61 years were included. Nonbridging external
fixation showed statistically significant improvement in both
dorsalangleand radial shorteningatall stages of revi ew,
successfully maintainingvolar tiltuntilfinalreview at one
year (8). There were no malunions in the nonbridging group
in this study.
Thus, themainradiologicaladvantage of nonbridging
external fixation is restoration and maintenance of the normal
volartiltofthe distal radius. In bridging external fixation,
reduction of the fracture depends on ligamentotaxis. Vo lar tilt
may not be restoredbecause the volar ligaments are shorter and
stronger than the dorsal ligaments and prevent full reduction
(23).With nonbridging external fixation,the reductionis
performed using thedistalpinsasjoyst icks,allowing the
surgeon direct controlofthe distal fragment and obviating the
need for ligamentotaxis.
Superior functional outcomes are also reported in nonbridging external fixation for acute fracturesofthe distal radius
compared to bridging techniques (8). In this study,the nonbridging groupgrip strength was restored to 87% of the opposite
normal side, allowing for appropriate hand dominance. Other
indices of functionalsoshowedsuperio rresults in the
nonbridging group.
The outcomes when nonbridging external fixation is used
for multifragmentary articular fractures are less optimal. Table 1
shows asummary of the reports available in the literatureon
nonbridging external fixation. In extra-articular and minimal
articular fractures, functional results are excellent. The only
exception to that rule is when the technique is used for severe
articular fractureswhen it is likely that the severity of the injury
dictates the outcome (22).
There have as yet been no randomized studies comparing
nonbridging external fixation with the more invasive technique
of plating forthe managementofunstabledistal radius
fractures. Vo lar locked plating has been introduced recently
for unstable distal radius fracturesinthe hope that fixed angle
devices would confer more stability in osteoporotic bone, and
that comparedtodorsalplat ingthere wouldbelesssoft
tissue irritation and therefore less need for implant removal.
The techniqueismoreinvasive than nonbridgingexternal
fixationand hasbeen widely usedwithverylimited data
available on its outcome.
One of the first reports of the technique was on 50 fractures
treated with avolar locked plate in patients with amean age of 62
years (24). In 21 of their fractures, the postoperative reduction
FIGURE 6 Alateral view of the distal radius showing overreduction of the same fracture as in Figures1–4.There is
excessive volar tilt.
148
&
McQueen
deteriorated by the final review,and in four there was sufficient
collapse of the fracturetoallow penetration of the radiocarpal
joint by the distal screws.The authors suggested that in patients
with significant osteoporosis bone grafting may be required to
augment the fixation, thus increasing the invasive nature of the
technique. Amore recent study has also shown aconcerning rate
of fracture collapse (10%), especiallyinpatients with severe
comminution(25). There also remainsasigni ficant rate of
secondary surgeryfor implantremoval duetoeitherflexor
tendon problems from the plate or extensor tendon irritation or
rupture due to screw penetration dorsally (24,25). Randomized
studies are required to compare this technique with established
techniques including nonbridging external fixation.
&
Osteotomy
Little is reported on the use of nonbridging external fixation for
distal radial osteotomy.Aseries of 23 patients were treated in
the author’s institution with nonbridging external fixators for
symptomatic malunion of the distal radius. There were statistically significant improvements in both dorsal angulation and
radial shortening, with dorsal angulation improving from a
mean of 18.68 to amean volar tilt of 6.58 at final review.All
functional measures were statistically significantly improved at
final review comparedwith preoperative levels except wrist
extension and key grip strength. The only major complications
weretwo patients with extensor pollicis longus ruptures. Radial
osteotomy with nonbridging external fixation provides aminimally invasive techniquefor distalradial osteotomy with
reliable radiological and functional results.
&
SUMMARY
Nonbridging external fixation of the distal radius for metaphyseal unstable fracturesisasimple minimally invasive technique
that allows the surgeon to obtain and maintain an excellent
reduction. Functional results are generally verysatisfactory
with arapid return to function and good long-term function.
Nonbridging external fixation has been shown to be superior
to bridgingexternalfixation in thetreatment of unstable
distal radiusfractures. The technique has not beendirectly
comparedtoeither dorsal or volar plating but is likely to have
less fracture collapse, fewer tendon problems, and thereforeless
secondary surgery.
&
FUTURE DIRECTION
Prospectiverandomizedstudies arerequiredtocompare
nonbridging external fixation with plating, especially locked
volar plating, for unstable extra and minimal articular fractures
of the distal radius. The use of the technique in severe articular
fractures should be defined more clearly. Thereisalsothe
opportunity to develop lighter and lower profile components
that are fully radiolucent in order to maximize function for the
patient while the fixator is in place.
&
SUMMATION POINTS
Indications
&
Unstable extra-articular and minimal intra-articular fractures of the distal radius
&
Severe articular fractures of the distal radius (using multiplanar K-wires)
&
Minimally invasive technique for distal radial osteotomy for
symptomatic malunion of the distal radius
Outcomes
&
Few malunions
&
Rapid rehabilitation and excellent long-term function
Complications
&
Minor pin track infections
&
Iatrogenic volar malunion
&
REFERENCES
1. McQueen MM. Fractures of the distal radius and ulna. In: CourtBrown CM, McQueen MM, Tornetta P, eds. Orthopedic Surgery
Essentials:Trauma. Philadelphia, PA:Lippincott Williams and
Wilkins, 2006:153–69.
2. Fernandez DL, Fleming MC. History,evolutionand biomechanics
of external fixation of the wrist joint. Injury 1994; 25(Suppl. 4):
S-D 1–-D 13.
3. AndersonR,O’Neil G. Comminuted fractures of the distal end of
the radius. Surg Gynaecol Obstet 1944; 78:434.
4. Jenkins NH, Mintowt-Czyt WJ.Mal-union and dysfunction in
Colles’ fracture: an anatomical and functional study.JHand Surg
1988; 13B:291–3.
5. McQueen MM, Caspers J. Colles’ fracture: does the anatomical
result affect the final function? JBone Joint Surg 1988; 70B:649–51.
6. SolgaardS.Functionafter distal radius fracture. Acta Orthop
Scand 1988; 59:39–42.
7. McQueen MM, Hajducka C, Court-Brown CM. Redisplaced
unstable fractures of the distal radius: aprospective randomised
comparison of four methods of treatment. JBone Joint Surg 1996;
78B:404–9.
8. McQueen MM. Redisplacedunstable fractures of the distal radius.
Arandomised prospective study of bridging versus non-bridging
external fixation. JBone Joint Surg 1998; 80B:665–9.
9. UchikuraC,Hirano J, Kudo F, Satomi K, Ohno T. Comparative
study of nonbridging and bridging external fixators for unstable
distal radius fractures. JOrthop Sci 2004; 9:560–5.
TABLE 1 Published Outcomes of NonbridgingExternal Fixation for Fracture of the Distal Radius
Fracture type MalunionFunction Major PTI EPL rupture
Jenkins (1987) (21) n Z 32 Extra-articular/nonarticular 2N/A 00
McQueen(1998) (8) n Z 30 Extra-articular/non articular0Grip strength 87% 02
Krishnan et al. (1998) (17) n Z 22 Intra-articular 029/30 excellent/good 20
McQueenetal. (1999) (13) n Z 20 Extra-articular/non articular1Grip strength 88% 10
Krishnan et al. (2003) (22) n Z 30 Intra-articular N/R Grip strength 45% 03
Flinkkila et al. (2003) (18) n Z 52 Extra-articular/non articular2Grip strength 90% 10
Gradl et al. (2005) (11) n Z 25 Extra-articular Severe articular196% excellent 20
Abbreviations:EPL, extensorpollicis longus; N/R, not reported; PTI, pin track infection.
Non-Bridging ExternalFixation of the Distal Radius&149
10. Bednar DA, Al-Harran H. Non-bridging external fixation for
fractures of the distal radius. JCan Chir 2004; 47(6):426–30.
11.Gradl G, Jupiter JB, GiererP,MittlmeierT.Fractures of the distal
radius treated with anonbridging external fixationtechnique using
multiplanar Kwires. JHand Surg2005; 30A:960–8.
12. Beumer A, McQueen MM. Fractures of the distal radius in lowdemand elderly patients: closed reduction of no value in 53 of 60
wrists. Acta Orthop Scand 2003; 74:98–100.
13. McQueen MM, Simpson D, Court-Brown CM. Metaphyseal
external fixationofredisplacedunstable distal radial fractures.
Use of the Hoffman 2compact external fixator.JOrthop Tr auma
1999; 13:501–5.
14. Fischer T, Koch P, Saager C, Kohut GN. The radio-radial external
fixator in the treatment of fractures of the distal radius. JHand Surg
1999; 24B(5):604–9.
15. Mackenney P, McQueen MM, Elton R. Prediction of instability in
distal radial fractures. JBone Joint Surg (Am) 2006; 88A:1944–51.
16. Reuben SS, Pristas R, Dixon D, Faruqh S, Madabhushi L, We rner S.
The incidence of CRPS after fasciectomy for Dupuytren’s contracture:aprospective observationalstudy of from anaesthetic
techniques. Anaesth Analg 2006; 102:499–503.
17. Krishnan J, Chipchase LS, Slavotinek J. Intraarticular fractures of
the distal radius treated with metaphyseal external fixation. JHand
Surg1998; 23B:396–9.
18. Flinkkila T, Ristiniemi J, Hyvonen P, Hamalainen M. Nonbridging
external fixationinthe treatment of unstable fractures of the distal
forearm. Arch Orthop Trauma Surg 2003; 123:349–52.
19. Rozental TD,Beredjiklian PK,BozentkaDJ. Functional outcome
and complications following two types of dorsal plating for
unstable fractures of the distal part of the radius. JBone Joint
Surg 2003; 85A:1956–60.
20. HerronM,Faraj A, Craigen MA. Dorsal plating for displacedintraarticular fractures of the distal radius. Injury 2003; 34:497–502.
21. Jenkins NH, Jones DG, Johnson SR, Mintowt-Czyt WJ .External
fixation of Colles’ fractures. An anatomical study.JBone Joint Surg
1987; 69B:207–11.
22. Krishnan J, Wigg AER, Walker RW,Slavotinekl J. Intra-articular
fractures of the distal radius: aprospective randomised controlled
trial comparing static bridging and dynamic non-bridging external
fixation. JHand Surg2003; 28B:417–21.
23. Bartosh RA, Saldana MJ. Intra-articular fractures of the distal
radius: acadavericstudy to determine if ligamentotaxis restores
radiopalmar tilt. JHand Surg1990; 15:18–21.
24. Drobetz D, Kutcha-Lissberg E. Osteosynthesis of distal radial
fractures with avolar locking screwplate system. Int Orthop
2003; 27:1–6.
25. Rozental TD,Blazar PE .Functional outcome and complications
after volar plating for dorsally displaced, unstable fractures of the
distal radius. JHand Surg2006; 31A:359–65.
150
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McQueen
19
Spanning Plating for Distal Radius Fractures
Anthony J. Lauder
Department of Orthopedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha,
Nebraska, U.S.A.
David S. Ruch
Department of Orthopedics, Duke University Medical Center, Durham, North Carolina, U.S.A.
Douglas P. Hanel
Section of Hand and Microvascular Surgery, Department of Orthopedics and Sports Medicine,
University of Washington,Seattle, Washington, U.S.A.
&
INTRODUCTION
Initially,asdescribed by Colles in 1814, distal radius fractures
wereconsidered entities that had universally good outcomes,
deserving only benign neglect as treatment (1). Although this
may occur for nondisplaced distal radius fractures that heal
uneventfully,many authors have demonstrated high complicationrates with conservative managementofmore
complicatedfractures (2,3). More recently,surgeonshave
becomemoreaggressive in theirtreatmentofdistalradius
fractures due to the recognition that good outcomes depend
on the restoration of normal anatomy (4–8). Even though distal
radiusfractures are exceedingly commoninjuries,itisthis
restorationofnormalanatomy, specificallythe articular
surface,which canpresent asignificant challengefor the
treating surgeon.
Furthermore, certain subsets of injuries including highenergy fracturesand fractures occurring in osteoporotic bone
pose particular problems. High-energy fractures with severe
comminution extending into themetaphyseal–diaphyseal
region and osteoporotic fracturesalso with comminution and
poor structural support make articular surface reconstruction
through open techniques adaunting task (Fig. 1). Adding to the
difficulty with surgical treatment for these types of distal radius
fractures is the fact that many of these patients present with
multiple injuries. Multiple injured patients, who often need
maximum use of their upper extremities to change assist with
mobilization,require rigidfracturefixation that dissipates
weight-bearing forces while providingenoughstabilityto
allow fracture healing. Ideally,amethod to treat distal radius
fractures in the face of polytraumatized patients or poor bone
stockwould provide rigidfixation, help maintainfracture
reduction, require minimal postoperative nursing or patient
care, be easily applied, and allow for early weight bearing.
Arelativelyfaciletechnique that providesthe support
necessary to allow early weight bearing is the spanning or
internal distractionplating of thedistalradius(Fig. 2).
Originally describedbyBurkeand Singer in 1998 (9), this
method bypassesthe injuredsegment with abridgeplate
from the distal shaft of the radius to the shaft of the second or
thirdmetacarpals. Advantages of this technique include the
following: ( i )iteffectively eliminates the compressive forcesat
the distal radius articularsurface seen whennon-spanning
devices are utilized; ( ii)itcan be much cheaper than external
fixators applied for similar fractures; ( iii)itallows for early
weight bearing and patient mobilization; ( iv)iteliminates the
need for pin site care and the complications that can stem from
infected tracts; ( v )itisindicated in severely comminuted or
osteoporotic bone whereproximal migrationofthe distal
fragments would be expected with weight-bearing and nonspanning devices; and ( vi)itimplements indirect reduction
techniques through ligamentotaxis that reduces the devascularization of fragments, which can occur with open techniques.
Important disadvantages of this techniqueinclude the
following: ( i )itentails prolonged immobilization of the wrist
during fracturehealing; ( ii)itrequires distraction to afford a
reduction that has been associated with complications (10–13);
and ( iii)itrequires asecond surgery for plate removal.
Certainly many other techniques, each with advantages
and disadvantages, exist for definitively treating distal radius
fractures that occur in osteoporotic bone or that stem from
high-energy insults. Closedreductionand percutaneous
pinning, aminimally invasive technique that can be performed
rapidly, providessomeadded stabilitycompared to closed
reduction alone. The stability added using percutaneous wires
is not enough to allow for early weight-bearing or aggressive
range of motion, however.External fixation, another option that
can be used as asupplement to Kirschner (K)-wires or by itself
to treat wrist fractures, has traditionally been implemented for
severely comminuted distal radius fractures. It bypasses the
injured segment and can provide avery rigid construct that
may allow for early weight bearing (11,14–-16). However,the
use of external fixation can be the source for many patient care
problems and complications. We ber and Szabo noted complication rates ranging from 52% to 63% in comminuted wrist
fracturestreated with external fixation (17). Furthermore, the
external pins not only add to the nursing burden by requiring
multiple cleanings each day,but also increasethe risk of local
infection and fixator loosening (18,19). Pin tract infections and
loosening may necessitate early removal of the external fixator,
making difficult anylong-term immobilizationthatmay be
desired for some high-energy injuries.
Most recently,the treatment of distal radius fractureshas
advanced rapidlywithalternative implants andtechniques
devised specifically for comminuted wrist fractures in single
extremity injuries. These innovative designs and techniques
include fixed-angle plates and small plates and/or wire forms
intendedfor fragment specific fixation(20,21).These new
implants are designed to be of low profile and to allow multiple
points of fixation to help restore astable, congruent articular
surface. The thinness of the implants and the fact that many are
designedfor volar placementalleviatethe problems with
extensor tendon irritation and rupture seen frequently with
bulkier implants placed dorsally (22,23). They are not without
complications, however.Implant breakage, tendon irritation/
rupture, loss of fixation, temporary paresthesias, and screw
perforation into the articularsurface arenoted problems
(20,24,25). Furthermore, these implants are not ideal for the
multiple injured patients or the highly comminuted fractures
with extension into the radial diaphysis. At this time, there is no
evidence that these newer plates and/or wire forms can support
the loads seen through the wrist in patients who requiretheir
upper extremities for transfers. Additionally,although the lowprofile volar locking plates with multiple screw options are
excellent for articular reconstruction, they are not designed to
provide the compression or rigidity required to adequately treat
aradial diaphyseal fracture (26,27).Severelycomminuted
osteoporotic fractures can also be problematic for these new
devices. This stems from the fact that these implants cannot
neutralize the compressive forces seen at the radiocarpal joint,
which can quickly lead to collapse of the weakened subchondral bone around ascrew,peg, or wire form.
The bridge plate, serving as an “internal fixator,” has many
biomechanical advantages that overcome the problems seen
with other implants. In astudy analyzing different external
fixator configurations, Behrens et al. noted that the rigidity of a
constructwas directly proportionaltothe proximity of the
longitudinal fixatorbar to the bone and fracture site (28).
Basedonthese findings, thebridgeplate,withits direct
contact to the radius and metacarpals, is the strongest possible
fixator construct. Additionally,while eliminating the compressive forcesseen at the radiocarpal joint, the bridge plate also
serves as adorsal buttress through its directcontact with the
dorsal cortex. The importance of the dorsal contact between the
plate and distal radius is underscored by astudy from Bartosh
and Saldana, showing that ligamentotaxis by itself was not a
sufficient means for restoring palmar tilt (29).
&
INDICATIONS
There are many situations in which the bridge plate for the distal
radius might be considered ideal. Current indications include
( i )high-energy injuries in polytraumatized patients where early
weight bearing on the upper extremities might be necessary for
transfers; ( ii)osteoporotic fractures with significant comminution that might lead to early collapse if the compressive forces
at the wrist are not neutralized; ( iii)high-energy fractureswith
extension into the metaphyseal–diaphyseal region of the distal
radius; and ( iv)fractures that would best be treated by bridging
techniques in patients who simply refuse to accept external
fixation as an option. Importantly, internal distractionor
bridge plating of the distal radius is not merely asubstitute
for external fixators. Certainly,externalfixators should still
have aplace in the wrist surgeon’s repertoire, especially when
there is significant soft tissue destruction and/or loss.
&
CONTRAINDICATIONS
The only true contraindication to bridge plating adistal radius
is apatient who, because of other injuries, cannot safely tolerate
the procedure. Tw orelative contraindications include ( i )the
presence of volar fracturefragments that do not reduce with
(A)
(B)
FIGURE 1 ( A) Anteroposterior radiographdemonstrating
high-energy fracture to distal radius with severe comminution extending into the metaphyseal–diaphysealregion. ( B)
Lateral radiograph of the same injury.
152
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Lauder et al.
distraction (these types of injuries may be better served with a
volarapproachand platingtechniquestosecure thefree
fragments) and ( ii)injuries that result in soft tissue loss that
would leave the plate exposed.
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PREOPERATIVE EVALUATION
As with any fractureofthe distal radius, preoperative radiographicevaluation should includeposteroanterior(PA),
oblique, and lateral views. The PA view should be taken with
the shoulder in neutral rotation and abducted 908 ,elbow flexed
908 ,and the forearmflat on the radiographic cassette. Atrue PA
view is noted when the ulnar and radial styloids make up the
far lateral and medial bordersofthe wrist on the X-ray (Fig. 3).
The lateral view should be taken with the beam perpendicular
to the long axis of the radial shaft. The quality of the lateral view
can be assessed by the position of the pisiform relative to the
distal pole of the scaphoid. In atrue lateral view,the pisiform
should overlapwiththe distal poleofthe scaphoid. Any
deviation from this suggests too much pronation or supination
of the wrist (Fig. 4) (30). Acomputed tomography (CT) scan
may be auseful adjunct in fractures where there is asuspected
free intra-articular fragment. Ty pically,these fragments will not
reduce with ligamentotaxis alone, and theCTcan provide
helpfulinformationoffracturelocation,which candirect
limited operative approaches to help restore joint congruity.
With thefragmentreduced,aspanning plate couldbe
applied. Finally,any preoperative evaluation of aperson with
ahigh-energy fracture should include the person as awhole,
realizing thatthe distal radius fracture may be arelatively
minor part of the entire picture.
Right
(A)
Right
(B)
FIGURE 2 ( A )Anteroposterior and ( B )lateral X-rays demonstrating a
comminuted distal radius fracture in apatient that sustained injuries to
multiple extremities. Note the supplementalKirschner wires providing
subchondral support and stabilization for smaller fragments.
FIGURE 3 Atrue anteroposterior view of the wrist with the ulnar and
radial styloids making up the outermost ulnar and radial portions on the
radiograph.
Spanning Plating for Distal Radius Fractures
&
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