Two Ring Hybrid External Fixation of Distal Tibial Fractures

Two-ring Hybrid External Fixation of Distal Tibial Fractures:A Review of 47 CasesJukka Ristiniemi, MD, Tapio Flinkkila, MD, PhD, Pekka Hyvonen, MD, PhD, Martti Lakovaara, MD,Harri Pakarinen, MD, Fausto Biancari, MD, PhD, and Pekka Jalovaara, MD, PhD

Background: The healing of a me-taphyseal fracture line is a major problemin cases of distal tibial fracture treatedwith external fixation.

Methods: Forty-seven distal tibialfractures treated with two-ring Ilizarovhybrid external fixation (16 AO/OTA typeA and 31 type C, 10 open) were followedup. Fracture reduction and union timewas evaluated and IOWA and RAND 36-Item Health Survey scores were used toassess functional outcome.

Results: Thirty-five fractures uniteduneventfully in a median time of 20 weeks,but 12 fractures needed additional proce-dures because of delayed union. Accord-ing to univariate analysis, the risk factorsfor a longer time needed for fracture union

were translational displacement and cur-rent smoking, and the risk factors for reop-eration because of delayed union translationaldisplacement fibular fracture fixation, and thenumber of cigarettes smoked per day. In mul-tivariate analysis, translational displace-ment was a risk factor for both longertime to fracture union and reoperationand fibular fracture fixation was a riskfactor for reoperation. If the translationaldisplacement was less than 3 mm, the re-operation rate was 6%, whereas if the dis-placement was more than 3 mm, it was83%. Reoperation was performed on 50%of the patients who underwent fibular fix-ation and on 15% of the patients who didnot undergo fibular fixation. There wereonly marginal decreases in the range of

motion and arthritis scores in the AO/OTAfracture types other than type C3. Therewere no significant differences in RAND36 scores between the general Finnishpopulation aged 18 to 64 years and ourpatients.

Conclusions: Hybrid external fixationof distal tibial fractures is associated withdelayed union, which is closely related to thedegree of residual translational displace-ment after reduction. Fixation of an associ-ated fibular fracture does not help toachieve better contact in the tibial fractureand increases the risk of delayed union.

Key Words: Tibial fractures, Pilonfractures, External fixation, Fractureunion, Delayed union, Nonunion.

J Trauma. 2007;62:174–183.

Distal tibial fractures are uncommon, accounting for only1% of all lower extremity fractures.1–3 Open reductionwith internal fixation (ORIF) often results in serious

wound healing problems and deep infection in high-energyfractures with soft-tissue injuries and severe comminution.4–7

External fixation is a commonly used treatment8,9 and hasbeen shown to result in acceptable functional outcome withfew serious complications.10

In the treatment of tibial shaft fractures, external fixatorshave a reputation of being “nonunion machines.”11 Clinicalstudies have shown that the quality of reduction, especiallyavoiding fracture gap, is extremely important.12,13 This fact hasreceived little attention in the literature on distal tibial fractures.The published series on hybrid14–16 or ankle bridging externalfixation8,9 shows a tendency for delayed union and need foradditional operations especially in metaphyseal fractures.

Several factors have been recognized as risk factorsfor delayed healing of fracture: sex, malnutrition, anemia,

and diabetes mellitus (systemic factors); corticosteroids,nonsteroidal anti-inflammatory drugs, chemotherapeuticcytotoxins, and smoking (pharmacological factors); andlocation of the fracture, high fracture energy, soft-tissuedisruption, infection, and nerve injury (local factors). Inaddition, some aspects of fracture care, such as motion atthe fracture site, the fracture gap, periosteal stripping dur-ing open reduction, and repeated manipulation of the frac-ture in the early phase increase the risk of delayed union.17

There are no studies specifically addressing the impact ofthe risk factors on the outcome of distal tibial fracturestreated with external fixation.

Our purpose was to review our experience in the treat-ment of distal tibial fractures with two-ring hybrid externalfixation and to evaluate the risk factors associated with de-layed union.

PATIENTS AND METHODSWithin the period from October 1998 to November

2003, 2,091 tibial or malleolar fractures were treated inOulu University Hospital. In all, 106 fractures were in theAO/OTA18 zone 43 (within 5 cm from the ankle joint).Thirteen zone 43 fractures with minimal displacementwere treated conservatively with a cast. Twenty-six type Bfractures and nine type C fractures with minor soft-tissueinjury were treated with open reduction and internal fixation. Sixtype C fractures with severe comminution of the distal tibia were

Submitted for publication May 2, 2005.Accepted for publication February 8, 2006.Copyright © 2007 by Lippincott Williams & Wilkins, Inc.From the Department of Orthopaedic and Trauma Surgery, University

Hospital of Oulu, Oulu, Finland.Address for reprints: Jukka Ristiniemi, MD, Department of Orthopae-

dic and Trauma Surgery, Oulu University Hospital, P.O. Box 90029, OYS,Oulu, Finland; email: [email protected].

DOI: 10.1097/01.ta.0000215424.00039.3b

The Journal of TRAUMA� Injury, Infection, and Critical Care

174 January 2007

treated with external fixation spanning the ankle joint. Fifty-twofractures with moderate or severe soft-tissue injury were selectedfor treatment with hybrid external fixation, and these patientsconstituted our study group.

Five patients were excluded from the study. Three ofthem could not be followed up, one patient had a highlycomminuted pilon fracture and early arthrodesis of the anklejoint, and another patient with multiple organ complicationsunderwent lower-limb amputation because of severe deepinfection. Thus, the present study included a total of 47patients (27 men and 20 women; mean age 49 years, range15–79 years). Twenty-four patients had a relatively low-energy injury (fall from less than 2 m, such as stairs orsporting injuries), whereas 23 had a high-energy injury (fallfrom over 2 m in 11 cases, road traffic crash in 5 cases, and

industrial accident in 7 cases). Eight patients had multipleinjuries. Data concerning the mechanism of injury, the AO/OTA fracture classification, the grade of open fractures, op-erative notes, and postoperative recovery were prospectivelycollected by specialists of orthopedic traumatology on a spe-cial form. Smoking, medication, body mass index, and con-comitant illnesses were obtained from the patient records.

Classification of FracturesThe fractures were classified according to the AO/OTA

classification.18 All of them were in zone 43 (within 5 cmfrom the ankle joint) and thus too distal for intramedullarynailing. Six fractures had diaphyseal extension (Fig. 1), butbifocal fractures, as described by Keating et al.,19 were notincluded in this series. There were 16 extra-articular type A

Fig. 1. Gustilo-Anderson grade 3B open fracture with diaphyseal extension (A) was treated with hybrid external fixation (B). There was 4mm of posterolateral translation in proximal fracture. The fracture was nailed for delayed union of the proximal fracture line after the distalfractures had healed (C). The fracture united in good alignment but there was malorientation of the ankle joint 3 years after the injury (D).

External Fixation of Distal Tibial Fractures

Volume 62 • Number 1 175

fractures (10 A1, 4 A2, 2 A3) and 31 type C fractures (10 C1,11 C2, and 10 C3). We do not consider type B fracturessuitable for hybrid external fixation. The metaphyseal fractureline was spiral in 13 cases, oblique in 5, transverse in 3, simplewedge in 11, and comminuted in 15. Forty-six fractures had anassociated fibular fracture. Ten fractures were open (2 type II, 2type IIIA, and 6 type IIIB) and classified according to theGustilo-Anderson classification.20 There were two minor(wedge �50% but �100%, �2.5 cm) and three moderate(wedge �50% but �100%, �2.5 cm) bone defects accordingto the modified Winquist-Hansen classification,21 which wererecorded during the operation of the fracture.

Operative TechniqueThirty-three injured limbs were initially splinted and kept

elevated to reduce swelling. Fourteen fractures involving serioussoft-tissue injuries were temporarily stabilized with external fix-ation crossing the ankle joint (Hoffman II, Stryker, Geneva,Switzerland). The definitive operation was performed within amean of 2 days (range, 0–15) on splinted fractures and within amean of 10 days (range, 5–27) on temporarily fixed fractures.The definitive operation was done by three orthopedic surgeonsspecializing in orthopedic traumatology.

In 26 cases, the joint line was reconstructed using mini-invasive techniques through incisions over the major fracturelines or percutaneously with 3.5-mm screws. The associatedfibular fracture was fixed with lag screws and/or a plate in 13cases and with a Rush pin in one case. The two-ring hybridexternal fixator (Ilizarov, Smith & Nephew, Memphis, TN)was used as a neutralization device. Distal tibial fragmentswere fixed with two to four 1.8-mm olive wires depending onthe size of the distal fragments, and one 5-mm half pin wasoccasionally also used if the distal fragment was largeenough. Diaphyseal fixation was performed by applying twoor three 5-mm titanium half pins with 70 to 90 degreesdivergence with reference to each other; one pin was con-nected to a metal ring and the others to the ring with a Ranchocube. The distal wires were connected to another full ring,and four threaded rods connected the two rings to each otherafter reduction of the metaphyseal-diaphyseal fracture. Noattempts were made to fix the distal and proximal fragmentsto each other by lag screws. Open fractures were treatedaccording to a staged protocol with intravenous antibiotics,immediate debridement, primary stabilization with temporarybridging external fixation, repeated revisions, and early soft-tissue coverage when the wound was clean (mean 11, range4–27 days). Primary bone grafting was done in one case andearly delayed bone grafting (mean 43, range 28–55 days) infour cases because of a metaphyseal bone defect after an openfracture. One fracture had to be bone grafted twice. One closedAO/OTA C3 fracture with diaphyseal extension and impactionwas bone grafted 4 weeks after the injury. Physiotherapy wasstarted 3 to 5 days after the operation to maintain ankle and kneemovements, and it was continued until the healing of the frac-ture. Partial weight bearing was allowed until the wound was

healed, after which full weight bearing was gradually allowed astolerated. The patients were scheduled for frame removal assoon as there was radiographic evidence of bridging callus ordisappearance of the fracture lines. The mean fixator time was19 weeks (range 8–40).

Radiographic MeasurementsRoutine anteroposterior and lateral digital radiographs

were used to measure the radiographic parameters from pos-treduction and follow-up films. PCView 1.2 DICOM 3.0(Jons-Finland Oy, Heinavesi, Finland) software was used forthis purpose. The measurements were made by the first au-thor. Displacement of the diaphyseal-metaphyseal fractureline was measured after reduction from the follow-up radio-graphs by the method described by Green and Gibbs.22 Todetermine the translation on both anteroposterior and lateralradiographs, lines were drawn from the exterior of the corti-ces of the proximal and distal fragments to the level of thefracture (Fig. 2C). The degree of true translation was calcu-lated according to the following formula:

Translation (mm) � �APtrans (mm)2 � LATtrans (mm)2,

where APtrans is the translation measured from the antero-posterior radiograph and LATtrans is the translation mea-sured from the lateral radiograph. All radiographs were readby the first author.

Follow-upThe patients were followed up monthly at the outpatient

clinic until the fracture united. The fractures were consideredunited when anteroposterior and lateral radiographs showedbridging of three out of four cortices or the fracture lines haddisappeared and there was no pain in the fracture upon weightbearing. Fracture union was defined as delayed when anadditional operation was required to promote fracture union.

Thirty-eight patients could be reviewed at the outpatientclinic after a mean time of 3 years and 5 months (range 2–6years). The range of motion of the ankle joint was measuredaccording to the method described by Lindsjo et al.23 Func-tional recovery was assessed using the IOWA ankle score24

and self-administered RAND 36-Item Health Survey.25 Thegeneral Finnish population was used as controls for RAND36-Item Health Survey scores. Standing anteroposterior andlateral radiographs were taken from both legs, including bothknee and subtalar joints. Joint line orientation was assessedby the method described by Paley et al.26 The fracture wasconsidered malunited if there was at least 10 degrees differ-ence in either anterior distal tibial angle (ADTA) or lateraldistal tibial angle (LDTA) compared with the uninjuredtibia. Osteoarthritis was assessed according to the method ofWilliams et al.27 by comparing the injured and uninjuredankle joints. An ankle free of osteoarthritis is given 10 points,and points are subtracted based on subchondral sclerosis (–1to –2), subchondral cysts (–1 to –2), osteophytes (–1 to –2),


176 January 2007

and joint space narrowing (–1 to –4). The clinical tests wereperformed by an independent research physiotherapist, andthe radiographs were analyzed by the first author.

Statistical AnalysisStatistical analysis was performed using SPSS statistical

software (SPSS v. 10.0.5, SPSS Inc., Chicago, IL). Continu-

ous variables are reported as median and 25th and 75thpercentiles. Fisher’s exact test with or without the MonteCarlo method was used for univariate analysis of categoricaldata. The Mann-Whitney test and the Kruskall-Wallis testwere used to assess the distribution of continuous variables inthe different subgroups. Spearman’s test was used to evaluatethe correlation between continuous variables. The receiver

Fig. 2. AO/OTA A1 type spiral fracture (A) was treated with a two-ring hybrid fixator (B). Three months after the injury there was no clinicalor radiologic sign of fracture union. Radiography (B) showed 7 mm lateral and 3 mm posterior translation, which was the biggestdisplacement in this series. According to the graphic presentation (C), there was 8 mm of true translation 27 degrees posterolaterallymeasured from the mediolateral plane. Additional pins were inserted into both fragments (D), and translation was corrected along the planeof deformity by sliding the two rings in reference to each other (E). The fracture united in 32 weeks and 4 years after the injury there wasgood alignment and fracture union (F).



operating characteristics (ROC) curve was used to identifythe best cutoff value of the degree of translation predisposingto delayed union requiring reoperation. Linear and logisticregressions with the help of backward selection were used formultivariable analysis. Only preoperative variables whose pvalues at univariate analysis were �0.05 were considered forinclusion in the regression model. A p � 0.05 was consideredstatistically significant.

RESULTSThe median time for fracture union was 20 weeks (25th

and 75th percentile 17–30). Thirty-five fractures united with-out additional operations during a median period of 19 (16–22) weeks, while 12 patients required reoperation because ofdelayed union in a median time of 21 (16–24) weeks from theinjury. Three type C fractures with diaphyseal extension

(Fig. 1) were nailed after the intra-articular fractures hadhealed. Two fractures were treated with ORIF and bonegrafting. In one case, external fixation with interfragmentarycompression (Fig. 2) was used. Six fractures were bone-grafted, one fracture twice. Eventually, all fractures united.

Functional ResultsFollow-up data were available for 38 patients. Clinical

ankle scores and RAND 36-Item Health Survey scores arepresented in Table 1. Overall, there were no significant dif-ferences between the general Finnish population aged 18 to64 years and our series in RAND 36-Item Health Surveyscores. The patients with AO/OTA type C fractures, openfractures, and complex metaphyseal fractures had lowerscores on some of the subscales compared with the otherpatients and the general population. Delayed union had no

Fig. 2. (Continued).


178 January 2007

negative influence on the functional outcome. Differences inthe range of motion between the injured and uninjured anklesare shown in Figure 3 and ankle osteoarthritis scores in Figure4. There were only marginal decreases in the range of motion inthe AO/OTA fracture types other than type C3. The lowestosteoarthritis scores were seen, as expected, in the fracture typesC2 and C3. Four cases had malunion. Once corrective osteot-omy was done, but the other patients refused further operations.None of the patients in the follow-up study had a shortening ofmore than 10 mm compared with the uninjured leg.

ComplicationsEighteen patients had pin-tract problems. Fifteen of these

had at least one pin-tract infection diagnosed as discharge,redness, swelling, and pain at the pin site and verified bybacterial culture. Four pins were replaced and one was re-moved. One patient who had the frame and all pins removedbecause of fulminant pin infection 8 weeks after the injuryalready displayed bridging callus, and the infection healedrapidly after the procedure. One patient had local osteomy-elitis in a diaphyseal pin tract. Local revision and bonegrafting were done, and the infection resolved. Other pin-tractinfections resolved after local revision and oral cefalexine(750 mg three times per day).

There were six other complications and ten reoperationsbecause of hardware problems. Broken distal wires werereplaced in a noncooperative woman. The fracture united in19 weeks without any other complications. One patient witha serious grade 3B open fracture had penetration of the distalpins through the tibialis posterior and extensor tendons, andthey were replaced in an early phase. One patient had irrita-tion of the tibialis posterior nerve, which resolved after re-placement of the distal wire. One patient had superficialperoneal nerve injury during plating of the fibula, and onepatient during wire insertion. Hypoesthesia after nerve injuriesremained permanent in both cases. One patient with type C3fracture, comminution, and bone defect resulting from impactionhad deep infection after joint line reconstruction and primarybone grafting. The infection resolved and the fracture unitedafter seven revisions, treatment with intravenous vancomysin(Vancosin) 2 g twice daily, and delayed bone grafting.

Risk Factors Predicting Delayed UnionThe risk factors significantly associated with a longer

time to fracture union according to univariate analysis weretranslational displacement (p � 0.010, r � 0376) and currentsmoking (p � 0.013). According to linear regression analy-sis, the degree of translation was the only independent pre-

Table 1 Comparison of IOWA Ankle Scores and RAND 36-item Health Survey Scores Between DifferentSubpopulations

Subscale IOWA AnkleScore

PhysicalFunctioning

RoleLimitations:

Physical

RoleLimitations:Emotional

Vitality MentalHealth

SocialFunctioning

SomaticPain

GeneralHealth

General population(n � 1,529)

90 74 78 65 81 83 78 68

Our series (n � 38) 79 (19) 78 (23) 76 (37) 84 (31) 71 (21) 75 (20) 84 (19) 74 (27) 64 (22)Age- and sex-adjusted

difference (Rand-36)�3.6 (24) 4.9 (37) 1.4 (19) 7.1 (22) 1.5 (20) 2.7 (19) 0.7 (27) 3 (19)

AO/OTA class Afracture (n � 10)

87 (11) 10 (21) 24 (22) �19 (16) 18 (15) 7.7 (14) 12 (18) 15 (12) 9.4 (11)

AO/OTA class Cfracture (n � 28)

75 (21) �7.6 (24) �1.3 (39) �7.2 (35) 3.5 (24) �0.5 (21) �0.5 (21) �3.9 (29) 0.9 (21)

Closed fracture(n � 30)

82 (17) 3.1 (20) 9.6 (32) �9.6 (31) 12.7 (18) 4.8 (17) 6.2 (18) 3.2 (26) 5.7 (19)

Open fracture(n � 8)

64 (23) �26.5 (25)* �1.3 (49) �12.6 (35) �12.1 (25)* �10.8 (24) �9.9 (20) �8.3 (32) �6.9 (19)

Low-energy fracture(n � 19)

85 (17) 5.6 (18) 13.8 (31) �12.9 (29) 14.3 (17) 6.7 (15) 10.6 (15) 9 (20) 5.2 (14)

High-energy fracture(n � 19)

72 (20) �12.4 (26)* �3.5 (41) �7.6 (35) 0.8 (25) �3.6 (23) �4.7 (21)* �7.2 (31) 1 (23)

Union (n � 27) 81 (18) �6 (22) �1.3 (37) �8.7 (32) 8.8 (20) 1.8 (20) 3.1 (20) 1.4 (26) 3.4 (22)Delayed union

(n � 11)74 (22) 3.1 (30) 21.9 (33) �14.3 (34) 2.8 (29) 0.5 (21) 1.7 (20) �1.2 (32) 1.8 (14)

Simple metaphysealfracture (n � 26)

84 (15) 3.3 (20) 14 (27) �12.5 (28) 4.2 (19) 4.2 (19) 9 (17) 4.5 (28) 5.5 (16)

Complex metaphysealfracture (n � 12)

65 (23)* �18.7 (27)* �14.7 (46) �5.6 (39) 1.4 (22) �4.2 (20) �10.3 (19)* �7.2 (25) �2.4 (25)

Values are mean (SD) or age- and sex-adjusted mean difference (SD). The general population consisted of the Finnish population aged 18to 64 years. The bolded numbers indicate the differences between our series and the age- (10-year interval) and sex-adjusted general Finnishpopulation.

* p � 0.05.



Fig. 3. Boxplot diagram of range of motion. Median and 25th and 75th percentiles. The y axis represents difference in degrees comparedwith uninjured ankle.

Fig. 4. Boxplot diagram of ankle osteoarthritis scores in the different AO/OTA fracture classes. Median and 25th and 75th percentiles.


180 January 2007

dictor of longer union time (regression coefficient 3.9; 95%confidence interval [CI]: 2.1–5.7; p � 0.001). Smoking de-layed fracture union by 10 weeks (regression coefficient 10.1,95% CI: 1–21; p � 0.070).

According to univariate analysis, the risk factors forreoperation because of delayed healing were residual trans-lational displacement after reduction (p � 0.0001), fibularfracture fixation (p � 0.025), and number of cigarettessmoked per day (p � 0.043). Multivariate logistic regressionanalysis showed that the degree of translation (odds ratio[OR] 2.1; 95% CI: 1.3–3.5; p � 0.004) and fibular fracturefixation (OR 19.4; 95% CI: 1.1–340; p � 0.043) increasedthe risk for reoperation. Reoperation was performed on 50%of the patients who underwent fibular fixation and on 15% ofthe patients who did not undergo fibular fixation.

The area under the ROC curve was 0.883 for the degreeof residual translation after reduction in predicting reopera-tion (95% CI: 0.7–1.03; p � 0.001). Its best cutoff value was3 mm (sensitivity 83.3%, specificity 94.3%), under whichvalue (translation �3 mm) the rate of reoperation was 6%,whereas above that value (translation �3 mm), it was 83%(p � 0.001). Fifty percent of the patients having had atranslation �3 mm had fibular fixation, and 22.9% of thosewith a translation �3 mm had fibular fixation (p � 0.14).There were no differences between the high- and low-energyfractures in the number of cases with translation �3 mm(42% versus 58%, p � 0.56) or fibular fixation (43% versus57%, p � 0.59). Clinical characteristics of the patients withand without delayed union are presented in Table 2.

There were two diabetic patients and four patients whowere on corticosteroids treatment for concomitant illnesses. Onepatient with rheumatoid arthritis had sodium aurathiomalate(Myocrisin) medication. None of these patients needed reopera-tion as a result of delayed healing. In this series, obesity or lowbody mass index did not have any negative influence on fractureunion.

DISCUSSIONWe found that hybrid external fixation of distal tibial

fractures is associated with a considerably high rate of de-layed unions. Translational displacement seems to be themost important factor leading to delayed union. Fixation of

an associated fibular fracture did not help to achieve bettercontact in the metaphyseal fracture of the tibia. In fact,fixation of the fibular fracture was associated with delayedunion. Translational displacement has been recognized as arisk factor for delayed union in the treatment of tibial shaftfractures,13 but it has received no attention in distal tibialfractures.

The rates of delayed union or nonunion of distal tibialfractures treated with external fixation have varied markedlyin recent reports, ranging from 8% to 40%.6,15,16,28 Anglen15

treated 63 distal fractures of the tibial plafond with eitherinternal fixation (27 fractures) or hybrid external fixation (34fractures). Twenty-nine patients in the hybrid group werefollowed up, and despite the high rate of primary bone graft-ing (5/29 fractures), six fractures had nonunion. Bone et al.,8

in their series of ankle-bridging external fixation, found that3 out of 20 fractures had nonunion. They reported that non-union mostly occurred in the most proximal fracture line, butdid not occur when this area was bone grafted primarily.They did not mention how many fractures were bone graftedprimarily. Barbieri et al.16 bone grafted 12 out of 37 fractures,and three showed nonunion. Pugh et al.28 compared 21 frac-tures treated with ankle-spanning external fixation, 15 frac-tures treated with a single-ring hybrid fixator and 24 fractureswith ORIF. Although there were no nonunions in the hybridgroup, seven patients required bone grafting to promoteunion. Our results are in accordance with these reports. Weagree also with the earlier authors that soft tissue disruption,comminution and displacement of the fracture as well ascompromised vascular supply of the distal tibia are importantfactors for delayed union in high-energy fractures.

An interesting finding was the relatively high number ofdelayed unions in simple (spiral, oblique, or simple wedge)metaphyseal fractures. About one third of simple metaphy-seal fractures displayed delayed union. Half of these fractureswere relatively low-energy injuries. This reflects the difficul-ties in controlling translational displacement in simple frac-tures, which may be because of a relatively intact soft tissueenvelope resisting reduction. The tolerance for displacementis small, only 3 mm, thus even the fracture hematoma mayblock closed reduction. Metaphyseal fracture is mostly ob-liquely or spirally oriented. In the external fixation device

Table 2 Clinical Characteristics of Patients Without or With Delayed Union

Group No Delayed Union (n � 35) Delayed Union (n � 12) p Value

Mean age (SD) 47 (15) 55 (12) 0.143Male 22 (63%) 7 (58%) 0.326Current smoker 9 (26%) 7 (58%) 0.075Open fracture 8 (23%) 2 (17%) 0.645Class A fracture/Class C fracture 11 (31%)/24 (69%) 5 (42%)/7 (58%) 0.725Bone defect 4 (11%) 1 (17%) 0.741Fracture with diaphyseal extension 3 (9%) 3 (25%) 0.165Simple metaphyseal fracture 21 (62%) 10 (83%) 0.285No. of fixed fibula fractures 7 (20%) 7 (58%) 0.025Low-energy injury 18 (51%) 6 (50%) 1.000



used here, interfragmentary movement mostly consists ofshearing rather than axial loading, which is generally thoughtto be beneficial for fracture healing.

The literature concerning the fixation of associated fib-ular fractures is controversial. In experimental studies, thefixation of associated fibular fractures has been shown to addstructural stability whenever external fixation of the tibialfracture is used.29,30 The other theoretical benefits are that thelength of the extremity can be preserved and the rotation ofthe tibial fracture can be controlled. Some authors have fixedassociated fibular fractures in conjunction with the externalfixation of distal tibial fractures,8,31 but there are no unam-biguous recommendations for this in the clinical studies.Williams et al.32 found that there were significantly moreserious complications in the cases where the fibular fracturewas fixed compared with those where it was not fixed. Theydid not find any significant differences in the mean uniontimes of tibial fractures. In our series, fibular fixation was anindependent factor leading to additional operations caused bydelayed fracture union. We hypothesize that fibular fixationmight delay the healing of the tibial metaphyseal fracture bykeeping the fibula at full length and not permitting axialloading of the tibial fracture. This hypothesis was supportedby some experimental and clinical studies,29,30,33 whichshowed that axial loading of the tibia is significantly de-creased when the fibular fracture is stabilized.

Delayed union had no remarkable effect on functional out-come. This is explained by the facts that a relatively highproportion of delayed unions were simple fractures expected toresult in a good functional outcome, and that the evaluation offunctional outcome was done when the delayed union hadhealed.

The weakness of the treatment method used here is theinsufficient control of translational displacement. It has beensuggested that plate and screw fixation would be better in thisrespect. In two recent studies, the two-stage method of initialexternal fixation and consequent plating of the distal tibialfracture after healing of the soft tissues resulted in goodfracture union and an acceptable rate of complications.34,35

Furthermore, the modern intramedullary nails enabling nail-ing of very distal tibial fractures seem like an attractivealternative, but there are no reports of their use in the verydistal tibial fractures available yet. Although hybrid externalfixation in this study was shown to be safe in the mostseverely comminuted fractures with soft-tissue injury, itsapplicability can be questioned in the treatment of the simplemetaphyseal fractures.

In conclusion, in patients with distal tibial fracturestreated with a hybrid external fixator, every effort should bemade to avoid more than 3-mm translational displacement. Ifthis is not feasible, early bone grafting or other methods foraccelerating fracture union should be considered. Fixation ofthe associated fibular fracture is not recommended.

REFERENCES1. Bone LB. Fractures of the tibial plafond. The pilon fracture. Orthop

Clin North Am. 1987;18:95–104.2. Ayeni JP. Pilon fractures of the tibia: a study based on 19 cases.

Injury. 1988;19:109–114.3. Bourne RB. Pylon fractures of the distal tibia. Clin Orthop. 1989;

240:42–46.4. McFerran MA, Smith SW, Boulas HJ, Schwartz HS. Complications

encountered in the treatment of pilon fractures. J Orthop Trauma.1992;6:195–200.

5. Teeny SM, Wiss DA. Open reduction and internal fixation of tibialplafond fractures. Variables contributing to poor results andcomplications. Clin Orthop. 1993;292:108–117.

6. Wyrsch B, McFerran MA, McAndrew M, et al. Operative treatmentof fractures of the tibial plafond. A randomized, prospective study.J Bone Joint Surg Am. 1996;78:1646–1657.

7. Blauth M, Bastian L, Krettek C, et al. Surgical options for thetreatment of severe tibial pilon fractures: a study of threetechniques. J Orthop Trauma. 2001;15:153–160.

8. Bone L, Stegemann P, McNamara K, Seibel R. External fixation ofseverely comminuted and open tibial pilon fractures. Clin Orthop.1993;292:101–107.

9. Marsh JL, Bonar S, Nepola JV, et al. Use of an articulated externalfixator for fractures of the tibial plafond. J Bone Joint Surg Am.1995;77:1498–1509.

10. Marsh JL, Weigel DP, Dirschl DR. Tibial plafond fractures. Howdo these ankles function over time? J Bone Joint Surg Am. 2003;85A:287–295.

11. Court-Brown C. Fractures of the tibia and fibula. In: Buckholz RWand Heckman JD, ed. Rockwood and Green‘s Fractures in Adults.5th Ed. Philadelphia: JB Lippincott, 2001; 1971.

12. Court-Brown CM, Hughes SPF. Hughes external fixation intreatment of tibial fractures. J R Soc Med. 1985;78:830–837.

13. Helland P, Boe A, Molster AO, et al. Open tibial fractures treatedwith the Ex-fi-re external fixation system. Clin Orthop. 1996;326:209–220.

14. Tornetta P 3rd, Weiner L, Bergman M, et al. Pilon fractures:treatment with combined internal and external fixation. J OrthopTrauma. 1993;7:489–496.

15. Anglen JO. Early outcome of hybrid external fixation for fracture ofthe distal tibia. J Orthop Trauma. 1999;13:92–97.

16. Barbieri R, Schenk R, Koval K, et al. Hybrid external fixation inthe treatment of tibial plafond fractures. Clin Orthop. 1996;332:16 –22.

17. Hayda RA, Brighton CT, Esterhai JL Jr. Pathophysiology ofdelayed healing. Clin Orthop 1998;355:S31–S40.

18. Muller ME, Nazarian S, Koch P, Schatzker J. The comprehensiveclassification of fractures of long bones. New York: Springer;1990.

19. Keating JF, Kuo RS, Court-Brown CM. Bifocal fractures of thetibia and fibula. Incidence, classification and treatment. J BoneJoint Surg Br. 1994;76:395– 400.

20. Gustilo RB, Anderson JT. Prevention of infection in the treatment ofone thousand and twenty-five open fractures of long bones:retrospective and prospective analyses. J Bone Joint Surg Am. 1976;58:453–458.

21. Robinson CM, McLauchlan G, Christie J, et al. Tibial fractures withbone loss treated by primary reamed intramedullary nailing. J BoneJoint Surg Br. 1995;77:906–913.

22. Green SA, Gibbs P. The relationship of angulation to translation infracture deformities. J Bone Joint Surg. 1994;76A:390–397.

23. Lindsjo U, Danckwardt-Lilliestrom G, Sahlstedt B. Measurement ofthe motion range in the loaded ankle. Clin Orthop. 1985;199:68–71.

24. Merchant TC, Dietz FR. Long-term follow-up after fractures of thetibial and fibular shafts. J Bone Joint Surg Am. 1989;71:599–606.


182 January 2007

25. Aalto A-M, Aro A, Teperi J. RAND 36 terveyteen liittyvanelamanlaadun mittarina. Saarijarvi:Gummerus Kirjapaino Oy; 1999.

26. Paley D, Tetsworth K. Mechanical axis deviation of the lower limbs.Preoperative planning of uniapical angular deformities of the tibia orfemur. Clin Orthop. 1992;280:48–64.

27. Williams TM, Nepola JV, DeCoster TA, et al. Factors affectingoutcome in tibial plafond fractures. Clin Orthop. 2004;423:93–98.

28. Pugh KJ, Wolinsky PR, McAndrew MP, Johnson KD. Tibial pilonfractures: a comparison of treatment methods. J Trauma. 1999;47:937–941.

29. Morrison KM, Ebraheim NA, Southworth SR, et al. Plating of thefibula. Its potential value as an adjunct to external fixation of thetibia. Clin Orthop. 1991;266:209–213.

30. Weber TG, Harrington RM, Henley MB, Tencer AF. The role offibular fixation in combined fractures of the tibia and fibula: abiomechanical investigation. J Orthop Trauma. 1997;11:206–211.

31. Saleh M, Shanahan MD, Fern ED. Intra-articular fractures of thedistal tibia: surgical management by limited internal fixation andarticulated distraction. Injury. 1993;24:37–40.

32. Williams TM, Marsh JL, Nepola JV, et al. External fixation oftibial plafond fractures: is routine plating of the fibula necessary?J Orthop Trauma. 1998;12:16 –20.

33. Watson JT. Analysis of Failure of Hybrid External FixationTechniques for the Treatment of Distal Tibial Pilon Fractures.Available online at: http://www.hwbf.org/ota/am/ota00/otapa/OTA00960.htm. Accessed November 9, 2006.

34. Patterson MJ, Cole JD. Two-staged delayed open reduction andinternal fixation of severe pilon fractures. J Orthop Trauma. 1999;13:85–91.

35. Sirkin M, Sanders R, DiPasquale T, Herscovici D Jr. A stagedprotocol for soft tissue management in the treatment of complexpilon fractures. J Orthop Trauma. 2004;18:S32–S38.



Two Ring Hybrid External Fixation of Distal Tibial Fractures

Documents

Transcript of Two Ring Hybrid External Fixation of Distal Tibial Fractures