DYNAMIC EXTERNAL FIXATION FOR COMPLEXINTRAARTICULAR PHALANGEAL FRACTURES

D. JOHNSON, E. TIERNAN, A. M. RICHARDS and R. P. COLE

From the Department of Plastic and Reconstructive Surgery, Salisbury District Hospital, Odstock, Salisbury, Wiltshire SP2 8BJ, UK

Intraarticular phalangeal fractures are difficult to treat. The advantages of using dynamic externalfixation devices include distraction of impacted fracture fragments and reduction in joint stiffnessby allowing early joint mobilization. Previous reports have concentrated on pilon fractures anddorsal fracture dislocations affecting the proximal interphalangeal joint. We report our experienceusing a dynamic external spring fixator in the management of 15 patients with a variety of fracturepatterns affecting the metacarpophalangeal, proximal interphalangeal and distal interphalangealjoints. In three cases the device spanned two adjacent joints. Long-term follow-up has shownexcellent range of joint movement and no major complications. We consider that this device is aneffective tool in the management of a range on complex intraarticular phalangeal fractures.Journal of Hand Surgery (British and European Volume, 2004) 29B: 1: 76–81

Keywords: dynamic, external fixation, phalangeal fractures

INTRODUCTION

Complex intraarticular phalangeal fractures withor without associated dislocation are difficult to treat.Conservative management comprising immobilizationwith splintage alone frequently produces a pooroutcome with stiffness, pain and a markedly reducedrange of movement (Stern et al., 1991). Open reductionand internal fixation is often technically difficult owingto comminution of the bone fragments. To circumventthese problems, a variety of static and dynamic externalfixation devices have been designed to treatsuch fractures of the interphalangeal joints. The abilityto provide both distraction at the fracture site andallow active mobilization offers the best solution tothe management of many of these fractures (Agee,1987; Allison, 1996; Fahmy, 1990; Hynes andGiddins, 2001; Inanami et al., 1993; Schenk, 1986;Suzuki et al., 1994).

We report our experience with a dynamic externalfixation device similar to that described by Allison(1996). In our series of 15 patients, we have extended theuse of this type of dynamic fixator to include a variety ofintraarticular phalangeal fracture patterns involving themetacarpophalangeal, proximal interphalangeal anddistal interphalangeal joints, as well as using the deviceto span two adjacent joints.

PATIENTS AND METHODS

The design of the device and the operative technique forits application are a modification of that described byAllison (1996). Briefly, under X-ray screening a 1.1 mmKirschner wire is positioned transversely through thecentre of rotation of the head of the bone immediately

proximal to the fracture. A second, parallel Kirschnerwire is passed through the bone at a point distal to thefracture. The planned distance between the two parallelK-wires is determined preoperatively with the use ofradiographs, and allows the springs to be prefabricatedby the maxillofacial technicians in our department. Eachspring consists of two single 1 mm stainless-steel coils inseries, with acrylic ferrules sealed around the ends ofeach limb, through the centre of which a hole is drilledin order to slot over the ends of the Kirschner wires(Fig 1). At rest the limbs of the device diverge(subtending an angle of 301 with the perpendicular),but by compressing the limbs to make them parallel,each spring is loaded with potential energy and thisprovides a distracting force when slotted onto theparallel transverse Kirschner wires. The distractionforce can be modified postoperatively by the additionof elastic bands between the two sides of the digit.

Provided there is sufficient soft-tissue coverage toallow ligamentotaxis, suitable cases for the technique

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Fig 1 Photograph of the spring fixator used in this study. Note theacrylic ferrules.

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include both closed and open intraarticular fractures ofthe metacarpophalangeal, proximal interphalangeal anddistal interphalangeal joints, in which there is comminu-tion as well as bony impaction.

RESULTS

Between January 1997 and July 2001, 15 cases weretreated with dynamic external fixation devices (Table 1).

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Table 1—Details of patients treated

Age (years)Sex (M/F)

Injury1 Digit2 Treatment delay(days)

Jointsspanned

Devicein situ(days)

Follow-up(months)

Complications Range ofmovement

1 28M Palmar fracture-dislocation (c) Little (d) 10 (salvage) PIP 37 2 Infection NR2 62M Shaft and condylar Index (nd) 0 PIP 44 10 None PIP 0–901

head P2 (o) DIP DIP 0–5513 23M Pilon P1 (c) Thumb (d) 2 MCP 29 55 Spring adjustment MCP 0–551

IP 0–8014n 27M Comminuted P2 Middle (d) 0 PIP 51 12 None PIP 0–901

shaft fracture (o) DIP 15–4515 18M Fracture both Ring (d) 1 PIP 25 41 None PIP 25–901

articular surfaces PIP joint (o) DIP DIP 0–9016 28M Palmar fracture-dislocation (c) Little (nd) 3 PIP 57 9 Additional K-wires

insertedPIP 25–851

7n 52M Palmar fracture-dislocation (c) Ring (d) 2 (salvage) PIP 58 41 Additional K-wiresinserted

PIP 0–901

8 18M Dorsal fracture Index (d) 0 PIP 25 3 Infection PIP 10–901dislocation (c) Spring adjustment

9 41F Dorsal fracture dislocation (c) Ring (nd) 11 PIP 28 58 None PIP 0–100110 19M Condylar head P2 (o) Ring (d) 4 (salvage) DIP 42 29 None DIP 0–60111 54M Comminuted P2 shaft

fracture (c)Ring (nd) 0 PIP 53 3 None PIP 0–701

12 55M Comminuted P1 Thumb (nd) 1 MCP 43 19 None MCP 0–501shaft fracture (o) IP IP 0–501

13 31M Comminuted P1 shaftfracture (o)

Little (d) 0 PIP NR 8 None PIP 0–751

14 29M Palmar fracture-dislocation (c) Little (nd) 2 PIP 38 1 None PIP 20–60115 40M Pilon P1 (c) Thumb (nd) 0 MCP 36 7 None MCP 0–451

1 o=Open; c=closed.2 d=Dominant; nd=non-dominant.nAdditional internal fixation performed at time of spring application. NR=not recorded; P1=proximal phalanx; P2=middle phalanx;

PIP=proximal interphalangeal joint; DIP=distal interphalangeal joint; MCP=metacarpophalangeal joint.

Fig 2 Palmar fracture-dislocation of the proximal interphalangeal joint of the little finger (case 6). (A) Lateral radiograph showing extent of bonyinjury; (B) 9 months postoperative result showing adequate bony union following management with spring fixator and Kirschner wires; (C,D) the range of movement of the proximal interphalangeal joint (25–851), at 9 months follow-up.

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The mean patient age was 35 (range, 18–62 years).Twelve cases were primary cases, 11 of which weretreated within a few days of their injury. One primarycase (case 9) presented late, leading to a delay intreatment of 11 days. Three cases were salvage (cases 1,7 and 10) following initial inadequate conservativefracture management.

A variety of fracture patterns were treated usingthe spring fixator. Six cases involving the proximalinterphalangeal joint were associated with dis-location (four palmar-fracture dislocations (Fig 2),two dorsal fracture dislocations (Fig 3)), and there weretwo pilon type fractures (Fig 4), four intraarticularcomminuted shaft fractures (Fig 5), two condylarhead fractures and one case where both articularsurfaces of the proximal interphalangeal joint werefractured.

Twelve cases involved a single joint. Of these, theproximal interphalangeal joint was involved in eightcases, the distal interphalangeal joint in one case, andthe metacarpophalangeal joint of the thumb in threecases. In three cases the spring fixator was positionedacross two adjacent joints with excellent long-termresults (cases 2, 5 and 12 in Table 1). One of theseinvolved an intraarticular impacted fracture of the headof the middle phalanx. Here we used the device to spanboth proximal interphalangeal and distal interphalan-geal joints: The second case involved an open commin-uted proximal phalanx fracture of the thumb treated bydynamic fixation spanning the metacarpophalangealand interphalangeal joints (Fig 5). In both these casesthe fracture healed with almost full range of jointmovement. The third case (case 5) was an impacted openfracture involving both proximal interphalangeal joint

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Fig 3 Dorsal fracture-dislocation of the proximal interphalangeal joint (case 9). (A) Lateral radiograph showing extent of bony injury; (B)adequate reduction achieved following application of the dynamic external spring fixator; (C) lateral radiograph showing bony union in thesame patient, after 8 months follow-up; (D, E) photographs of same patient demonstrating an excellent range of movement at 58 monthsfollow-up.

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surfaces. Here the device was positioned to span boththe proximal interphalangeal and distal interphalangealjoints. Long-term follow-up revealed a fixed flexiondeformity of 251 at the proximal interphalangeal jointbut active flexion to 901.

The average follow-up period was 19 (range, 1.5–58)months. Three patients had minor complications. Twohad wound infections requiring admission for IVantibiotics, while one patient required additionalKirschner wire fixation. Two patients required minoradjustments of the spring with elastic bands which wasundertaken in the outpatient clinic. In three cases it wasbeneficial to use supplementary internal fixation to fixlarge malrotated fracture fragments at the time of appli-cation of the spring fixator (cases 4, 7, 14 in Table 1).

Two of these cases were palmar fracture-dislocationswhich were not reduced with ligamentotaxis alone. Inone case with a palmar fracture-dislocation, the patientunderwent a second procedure where additional Kirsch-ner wires were inserted to stabilize a small fracturefragment (case 6).

All patients in our series complied fully with wearingthe device and none found it particularly cumbersome.The long-term follow available in 10 out ofthe 15 patients showed excellent range of movementat the affected joints. Only four out of 15 patientslost full extension of the affected joint. There were nocases of chronic pain or osteomyelitis. Ranges ofmovement were recorded on 14 patients and are shownin Table 1.

DISCUSSION

The management of complex intraarticular phalangealfractures is difficult. Immobilization using splints leadsto joint stiffness, while internal fixation is technicallydifficult and frequently impossible due to comminutionof fragments.

The advantage of a dynamic external fixation device isthat it can apply traction as well as allowing movementat the joint. The traction prevents shortening of theligaments, which contributes to joint stiffness. Activeand passive movement allows tendon gliding and helpslimit periarticular adhesions. Cumbersome devices suchas the banjo-style outrigger frames achieve distraction,but full active motion is sometimes limited (Morganet al., 1995; Robertson et al., 1946; Schenk, 1986). Anumber of true dynamic systems allow active movement(Agee, 1987; Allison, 1996; De Soras et al., 1997; Hynesand Giddins, 2001; Inanami et al., 1993; Suzuki et al.,1993).

Our modification of the spring fixator device de-scribed by Allison (1996) uses acrylic instead of stainlesssteel ferrules. The ferrules make the whole device morestable and prevent rocking and slippage between thetransverse Kirschner wires and the spring itself. Acrylicis readily available in the maxillofacial laboratory and itis easier to cure and seal this around the ends of thespring than having to manufacture steel ferrules whichneed to be clipped into place. Acrylic also has theadvantage of decreasing the friction at the point ofcontact between the transverse Kirschner wire and thespring component.

We have found the application of the device useful fora number of different phalangeal fracture patternsirrespective of the presence of an open wound, providedthere is sufficient soft-tissue coverage to allow ligamen-totaxis. Six out of 15 cases in this series were openfractures. In addition to its established use in themanagement of pilon fractures and dorsal fracture-dislocations of the proximal interphalangeal joint

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Fig 4 Pilon type fracture of the proximal phalanx of the thumb (case15: Table 1). (A, B) Preoperative radiographs showing the pilonfracture; (C, D). Postoperative radiographs of the same patientat 7 months follow-up.

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(Allison, 1996), this series has extended the appli-cation of the dynamic external spring fixation deviceto include palmar fracture-dislocations, fracturesinvolving the metacarpophalangeal and distal interpha-langeal joints, condylar head fractures and impactedphalangeal shaft fractures. The spring fixator aloneis useful in the fixation of both dorsal and palmarfracture dislocations provided the dislocation can bereduced and held reduced by ligamentotaxis (two out offour cases in this series). If dislocation is still presentafter distraction then additional Kirschner wire fixationwill be required.

The complication rate following use of the device waslow in this series. Bony union was achieved in every caseand there were no major complications. Only threeminor complications occurred, none of which requiredremoval of the fixator. Our stiffest joints were allproximal interphalangeal joints (25–901; 25–851; 20–601)in young patients who were able to return to workwithout chronic pain. All patients were reported to bepain free. Although our series comprises a range offracture patterns, with or without associated dislocation,the results compare favourably with previous reports(Allison, 1996; De Soras et al., 1997; Fahmy et al., 1990;Inanami et al., 1993; Stern et al., 1991).

Acknowledgements

We thank the patients for their help in participating in this study. We thank KenRussell and Mark Richards from the maxillofacial laboratory in SalisburyDistrict Hospital for help with design and construction of the spring fixationdevices.

References

Agee JM (1987). Unstable fracture dislocations of the proximal interphalangealjoint: treatment with the force couple splint. Clinical Orthopaedics andRelated Research, 214: 101–112.

Allison DM (1996). Fractures of the base of the middle phalanx treated by adynamic external fixation device. Journal of Hand Surgery, 21B: 305–310.

De Soras X, De Mourgues P, Guinard D, Moutete F (1997). Pins and rubberstraction system. Journal of Hand Surgery, 22B: 730–735.

Fahmy NRM (1990). The Stockport serpentine spring system for the treatmentof displaced comminuted intra-articular phalangeal fractures. Journal ofHand Surgery, 15B: 303–311.

Hynes MC, Giddins GEB (2001). Dynamic external fixation for pilon fracturesof the interphalangeal joints. Journal of Hand Surgery, 26B: 122–124.

Inanami H, Ninomiya S, Okutsa I, Tarui T, Fujiwara N (1993). Dynamicexternal fixation for fracture-dislocation of the proximal interphalangealjoint. Journal of Hand Surgery, 18A: 160–164.

Morgan JP, Gordon DA, Klug MS, Perry PE, Barre PS (1995). Dynamic digitaltraction for unstable comminuted intra-articular fracture-dislocation ofthe proximal interphalangeal joint. Journal of Hand Surgery, 20A: 565–573.

Robertson RC, Cawley JJ, Faris AM (1946). Treatment of fracture-dislocationof the interphalangeal joints of the hand. Journal of Bone and JointSurgery, 28: 68–70.

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Fig 5 Intraarticular comminuted fracture of the proximal phalanx of the thumb (case 12). (A, B) AP and lateral radiographs showing springfixator in position; (C, D) same views showing bony union at 19 months follow-up. (E, F) photographs showing excellent range ofmovement at 19 months follow-up.

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Schenk RR (1986). Dynamic traction and early passive movement for fracturesof the proximal interphalangeal joint. Journal of Hand Surgery, 11A:850–858.

Stern PJ, Roman RJ, Kiefhaber TR, McDonough JJ (1991). Pilon fractures of theproximal interphalangeal joint. Journal of Hand Surgery, 16A: 844–850.

Suzuki Y, Matsunaga T, Sato S, Yokoi T (1994). The pins and rubbers tractionsystem for treatment of comminuted intraarticular fractures andfracture-dislocations in the hand. Journal of Hand Surgery, 19B: 98–107.

Received: 17 January 2003Accepted after revision: 4 August 2003

Mr David Johnson, Maple Lodge, Manor Road, South Hinksey, Oxford OX1 5AS, UK.Tel.: +44-1865-327067; E-mail address: davidjohnson plastic@lycos.co.uk

r 2003 The British Society for Surgery of the Hand. Published by Elsevier Ltd. All rightsreserved.doi:10.1016/j.jhsb.2003.08.009 available online at http://www.sciencedirect.com

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