Use of the Ilizarov method as a salvage procedure in infected nonunion of the distal femur with bone loss, The

use of the Ilizarov method as a salvage procedure in infected nonunion of the distal femur with bone loss, The

Saridis, A

We reviewed 13 patients with infected nonunion of the distal femur and bone loss, who had been treated by radical surgical debridement and the application of an Ilizarov external fixator. All had severely restricted movement of the knee and a mean of 3.1 previous operations. The mean length of the bony defect was 8.3 cm and no patient was able to bear weight.

The mean external fixation time was 309.8 days. According to Paley’s grading system, eight patients had an excellent clinical and radiological result and seven excellent and good functional results. Bony union, the ability to bear weight fully, and resolution of the infection were achieved in all the patients. The external fixation time was increased when the definitive treatment started six months or more after the initial trauma, the patient had been subjected to more than four previous operations and the initial operation had been open reduction and internal fixation.

In distal femoral fractures bone loss and associated contamination in open high-energy fractures, devitalisation of metaphyseal bone fragments from extensive surgical exposure1 and the use of bulky internal fixation may result in an infected nonunion. A short distal fragment, poor bone quality and compromised soft tissues are also associated with this outcome. Union may be achieved with deformity and leg-length discrepancy leading to posttraumatic osteoarthritis and stiffness of the knee.2-5 This may necessitate arthrodesis as a salvage procedure,6 and in some cases amputation may be required.

Although the Ilizarov external device has been described for use in the management of infected nonunion in general,7-9 to our knowledge there have been few reports regarding the treatment of infected nonunion of the distal femur with bone loss. In this retrospective study we have analysed the results of treatment of this condition using the Ilizarov external device in an attempt to salvage the limb and to maximise its function.

Patients and Methods

We reviewed the records of 13 adult patients who were treated with the Ilizarov system for infected nonunion of the distal femur and bone loss between January 1993 and December 2001. The inclusion criteria were the presence of such a problem with bone loss of 3 cm or more at a maximum distance of 9 cm from the knee.4

There were ten men and three women with a mean age of 34.6 years (19 to 55). The non-union resulted from open high-energy complex fractures of the distal femur, type III B in ten and type III C in three according to the classification of Gustilo and Anderson.10 Road-traffic accidents were the cause in 11 patients and gunshot injuries in the remaining two, with the left side affected in seven. The mean interval from the original injury to application of the Ilizarov fixator was 12.3 months (3 to 33). The initial treatment of the fracture consisted of open reduction and internal fixation (ORIF) in five patients, unilateral transarticular external fixation in seven and hybrid external fixation in one (Table I). A total of 40 operations had been performed before the definitive treatment, including internal and external fixation, intramedullary nailing, bone grafting, wound debridement and the use of myofasciocutaneous flaps. The mean number of previous surgical procedures was three (1 to 5). The mean number of interventions for the five patients who had initial ORIF was four operations and for those with initial external fixation it was two.

The mean length of the bone defect was 8.3 cm (3 to 18). In five patients the infection was active but without drainage, and in the remaining eight there was active purulent drainage. Staphylococcus aureus was the responsible organism in seven patients, Psendomonas aeruginosa in four and Escherichia coli and streptococcus type B in two patients each (Table I).

At the time of definitive treatment all patients had severe limitation of movement of the knee and in four, this joint was completely stiff. In some cases it was impossible to be certain whether the movement clinically detected was occurring at the knee or at the adjacent nonunion or in combination. Seven patients had moderate or severe post-traumatic osteoarthritis of the knee with radiologically-identified irregularity of the articular surface and a decreased joint space. Moderate to severe disuse osteopenia of the distal femoral fragment and extensive scarring were present in every patient and none was able to bear weight.

Pre-operatively the location of sinus tracts, previous scars, and the neurovascular condition were carefully evaluated. Imaging included plain radiography, tomography, CT, MRI and scintigraphy, which were used to identify the severity of the infection and the extent of infected and necrotic bone. Intra-operatively, sinography with Methylene Blue was used in eight patients with active infection to delineate the extent of the infection and bone destruction. Nevertheless, being in the metaphyseal area, the full extent of the infection could be determined only by inspection at operation.1

Operative technique. The infected area was exposed in all 13 patients by an extensive lateral approach through the less damaged soft tissues in order to remove all loose implants and all infected and non-viable tissue. Samples thus obtained were sent for Gram staining, culture and sensitivity (aerobic/anaerobic) and fungal and mycobacterial cultures.

The bone ends were freshened, the medullary canal reconstituted and open reduction of the main fragments was performed to achieve the best possible contact between them. Impaction of the shaft of the femur into the condylar area was attempted to increase internal stability at the site of the defect in each case.9,11

Acute docking was possible in ten patients, while acute shortening of the site of the defect in order to improve soft-tissue cover and circulation was performed in three with bone loss of more than 6 cm. In our experience acute shortening for more than 6 cm of femoral bone loss compromises the soft tissues and may give deleterious effects.

After the acute shortening or acute docking an Ilizarov external device (Smith & Nephew Orthopaedics, Memphis, Tennessee) was applied. Primary wound closure was performed in eight cases followed by adequate drainage. Two different techniques of bifocal osteosynthesis7,9 were used (Table II). In ten patients bifocal combined compression-distraction osteosynthesis was undertaken. In two of these with extensive soft-tissue damage and aggressive purulent infection, a second-stage corticotomy was performed at one and three months post-operatively. In three patients bifocal consecutive distraction-compression osteosynthesis was carried out. Proximal, subtrochanteric, corticotomy was performed in each to restore initial femoral length by filling the bone defect.

A standard bifocal circular frame for infected nonunion with bone loss at the distal femur consisted of three or four rings and one proximal semicircular ring (Fig. 1). In four patients with short distal fragments and considerable instability in the interfragmentary area, transarticular circular ring fixation on the proximal tibia without hinges was used to enhance stability and to protect the distal fixation.3,12 Additional surgical procedures after the application of the Ilizarov frame were required in some patients to eradicate the infection and encourage union. These included repeated debridement in four, modification of the external fixator in five, a myofasciocutaneous flap in one and freshening of the bone ends and iliac bone grafting in two with sclerotic avascular bone ends and no progress to union at the docking site.

Post-operative care. All patients received a course of antibiotics for at least four to six weeks post-operatively according to the microbiological results. The erythrocyte sedimentation rate and the level of C-reactive protein were monitored on a regular basis. Thromboprophylaxis with low-molecular-weight heparin was given to each patient. The latency period before commencing bone transportation was three to five days and the rate of distraction at the site of the corticotomy ranged from 0.5 to 1.25 mm per day depending on the regenerative capacity, pain experienced at the corticotomy and the reaction at the hip. When docking was achieved, interfragmentary compression was continued at the rate of 0.5 mm per day for five to seven days and once consolidation had commenced at a rate 0.25 to 0.5 mm per week. Patients were encouraged to bear partial weight progressively with crutches on the second day after surgery. Quadriceps isometric exercises were started immediately after the operation to maintain or increase movement of the knee and muscle strength.

After the removal of the external fixator, the patients were restricted to partial weight-bearing for four to six weeks and no brace was used. Full weight-bearing was allowed between the fourth and tenth week post-operatively, based on clinical and radiological evidence of healing at the nonunion and at the site of lengthening. All patients returned for routine, clinical and radiological follow-up every month after operation until the Ilizarov device was removed, and every three months in the following year.

Post-operative radiographs were evaluated for residual malalignment and evidence of union. Radiological union was defined as the absence of a radiolucent line at the site of the nonunion and filling of the bone defect with new bone13 at a minimum of three cortices on standard anteroposterior and lateral radiographs.14 The results were assessed using the functional and radiological scoring system described by Paley and Maar.15

Results

The mean follow-up after removal of the frame was 42.4 months (19 to 72). No patient was lost to follow-up.

The mean external fixator time was 309.8 days (136 to 607) which correlated with the final lengthening achieved (Table II). The mean external fixator time when definitive treatment with application of the Ilizarov frame began early (

The number of previous operations was also of some predictive value. When the patient had been subjected to one to three operations before initiation of definitive treatment, the external fixator time was 228 days but for four and five operations it was 367.8 days, an increase of 61.3%. Additionally, the nature of the previous operations was of considerable predictive value in determining such time. In our series, in five patients (cases 1, 2, 3, 4 and 12) with primary ORIF, the mean time was prolonged to 471.6 days compared with the total mean of 309.8 days, an increase of 52.4%, and reduced to 208.7 days in the remaining patients with conventional external fixation as the initial treatment, a decrease of 32.6%. In the ORIF group the end functional result was also worse; in four patients it was fair and in one poor.

Bone. Clinical and radiological union and elimination of infection were achieved in all 13 patients. According to Paley and Maar’s grading system,15 eight patients had excellent, four good, and one a fair result. Five patients developed mild axial deformity of more than 5°, two at the regenerate site, two at the site of nonunion and one at both sites. Residual leg-length discrepancy greater than 2.5 cm was found in only one patient.

Function. At the time of the latest follow-up, all 13 patients were able to bear weight fully on the affected leg without any walking aid or brace. They had no pain or only mild pain when undertaking activities of daily living. The functional result was excellent in three patients, good in four, fair in four, and poor in two (Fig. 2). Although seven patients had an obvious limp, they were still able to perform the normal activities of daily living. In three patients (cases 5, 7, and 9) with an interval between injury and application of the Ilizarov external fixator of less than four months, a full range of movement of the knee was regained. A reduction of knee flexion to less than 90° was observed in the remaining ten patients. Five had satisfactory functional movement. Improvement in knee function occurred in most of these patients up to six months after removal of the frame. In five patients who had initial ORIF, a large bone defect and prolonged external fixation time (cases 1, 2, 3, 4 and 12), movement of the knee was restricted to 0° to 10°. Two of these patients underwent quadricepsplasty after the removal of the Ilizarov device in an attempt to address the stiffness, but had no significant improvement. No patient required arthrodesis of the knee.

Complications. There were no neurovascular intra-operative complications and no patient developed a neurovascular deficit or a compartment syndrome. The most common complication was pin-track infection especially in the distal segment as a result of severe osteopenia and poor soft-tissue cover. In nine patients with grade-3 infection according to Paley’s classification,16 the wires had to be removed and replaced under local anaesthesia. Prevention of pin-track infection was attempted by insertion of the wires through healthy skin, re-tensioning of loose wires and the use of counter-opposing olive wires, meticulous cleaning and, occasionally, administration of oral antibiotics after tests for culture and sensitivity. Continuous mild pain requiring analgesia was felt in all patients during the distraction phase. One non-displaced re-fracture at the docking site, which occurred two months after premature removal of the external fixator, was treated by re-application of the Ilizarov frame for three months.

Discussion

Infected nonunion of the distal femur with associated bone loss represents one of the most difficult problems in orthopaedic practice.17 Apart from high-energy trauma, predisposing factors include the proximity to the knee and the distracting pull of gastrocnemius, previous surgical interventions with extensive dissection and inadequate initial fixation.5 The presence of infection in this area makes treatment even harder. Specific problems related to this condition include lost bone with poor soft-tissue cover and scarring, deformity, shortening, post-traumatic osteoarthritis and stiffness in the knee.3,5

In our study, the cause of all the fractures was high-energy trauma with extensive disruption of the soft-tissue envelope and blood supply. Despite the fact that our series was relatively small it is noteworthy that the external fixator time reflected the extent of bone restoration required, the delay in commencement of definitive treatment, the number of previous interventions and the nature of the initial stabilisation of the fracture.

Unilateral temporary transarticular external fixators can be applied easily and rapidly and are popular for the initial management of high-energy fractures of the femur. These protect the remaining blood supply, avoid shortening and gross malalignment, while allowing adequate access for wound care. However, because of eccentric loading there is an increased risk of angular and shear displacement at the site of the fracture.18 Current studies report good and satisfactory results with primary application of the Ilizarov external fixator for severely comminuted and open fractures of the distal femur with extensive soft-tissue injury.12,19,20

The use of the Ilizarov external device for definitive fixation of fractures of the distal femur is the safest and most effective method since it provides adequate fixation and stabilisation at the site of the fracture, thus increasing osseous healing and decreasing infection.12,19,20 In the presence of infection aggressive debridement has been shown to be the cornerstone of successful treatment.” In our series the use of the Ilizarov method offered limb salvage with no need for arthrodesis or amputation.

No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.

References

1. Kretek C, Schandelmaier P, Tscheme H. Distal femoral fractures: transarticular reconstruction, percutaneous plate osteosynthesis and retrograde nailing. Unfallchirurg 1996:99:2-10 (in German).

2. Wu CC, Shih CH. Distal femoral non-union treated with interlocking nailing. J Trauma 1991;31:1659-62.

3. Ali F, Saleh M. Treatment of distal femoral non-unions by external fixation with simultaneous length and alignment correction. Injury 2002;33:127-34.

4. Bellabarba C, Ricci WM, Bolhofner BR. Indirect reduction and plating of distal femoral non-unions. JOrthop Traums 2002;16:287-96.

5. Johnson KD, Hicken G. Distal femoral fractures. Orthop Clin North Am 1987;18: 115-32.

6. Webb LX. Bone defect non-union of the lower extremity. Tech Orthop 2001;164: 387-97.

7. Ilizarov GA. Transosseous osteosynthesis. Theoretical and clinical aspects of the regeneration and growth of tissue. Berlin: Springer-Verlag, 1992.

8. Green SA. Skeletal defects: a comparison of bone grafting and bone transport for segmentai skeletal defects. Clin Orthop 1994;301:111-17.

9. Paley D, Catagni MA, Argnani F, et al. Ilizarov treatment of tibial non-unions with bone loss. Clin Orthop 1989;241:146-65.

10. Gustilo RB, Anderson JT. Prevention of infection in the treatment of one thousand and twenty five open fractures of long bones: retrospective and prospective analyses. J Bone Joint Surg [Am] 1976;58-A:453-8.

11. Song HR, Cho SH, Koo KH, et al. Tibial bone defects treated by internal bone transport using the Ilizarov method, lnt Orthop 1998;22:293-7.

12. Arazi M, Memik R, Ogun TC, YeI M. Ilizarov external fixation for severely comminuted supracondylar and intercondylar fractures of the distal femur. J Bone Joint Surg [Br] 2001;83-B:663-7.

13. Wang JW, Weng LH. Treatment of distal femoral non-union with internal fixation, cortical allograft struts, and autogenous bone-grafting. J Bone Joint Surg [Am] 2003;85-A:436-40.

14. Banaszkiewicz PA, Sabboubeh A, McLeod I, Maffulli N. Femoral exchange nailing for aseptic non-union: not the end to all problems. Injury 2003:34:349-56.

15. Paley D, Maar DC. Ilizarov bone transport treatment for tibial defects. J Orthop Trauma 2000:14:76-85.

16. Paley D. Problems, obstacles and complications of limb lengthening by the Ilizarov technique. CUn Orthop 1990;250:81-104.

17. Bolhofner BR, Carmen B, Clifford P. The result of open reduction and internal fixation of distal femur fractures using a biologic (indirect) reduction technique. J Orthop Trauma 1996:10:372-7.

18. Aronson J. Limb-lengthening, skeletal reconstruction, and bone transport with the Ilizarov method. J Bone Joint Surg [Am] 1997;79-A:1243-58.

19. Hutson JJ Jr, Zych GA. Treatment of comminuted intraarticular distal femur fractures with limited internal and external tensioned wire fixation. J Orthop Trauma 2000:14:405-13.

20. Ramesh LJ, Rajkumar SA, Rajendra R, et al. Ilizarov ring fixation and fibular strut grafting for C3 distal femoral fractures. J Orthop Surg (Hong Kong) 2004;12:91-5.

21. Marsh DR, Shah S, Elliot J, Kurdy N. The Ilizarov method in non-union, malunion and infection of fractures. J Bone Joint Surg[Br] 1997;79-B:273-9.

A. Saridis, E. Panagiotopoulos, M. Tyllianakis, C. Matzaroglou, N. Vandoros, E. Lambiris

From The University of P air as, Rio Patras, Greece

* A. Saridis, MD, Consultant Orthopaedic Surgeon

* E. Panagiotopoulos, MD, Associate Professor

M. Tyllianakis, MD, Associate Professor

* C. Matzaroglou, MD, Consultant Orthopaedic Surgeon

* N. Vandoros, MD, Consultant Orthopaedic Surgeon

* E. Lambiris, MD, Professor

Department of Orthopaedics

University of Patras, Rio Patras 26504, Greece.

Correspondence should be sent to Dr E. Panagiotopoulos; e-mail: ecpanagi@med.upatras.gr

© 2006 British Editorial Society of Bone and Joint Surgery

doi:10.1302/0301-620X.88B2. 16976 $2.00

J Bone Joint Surg [Br] 2006;88-B:232-7.

Received 14 July 2005; Accepted 7 October 2005

Copyright British Editorial Society of Bone & Joint Surgery Feb 2006

Provided by ProQuest Information and Learning Company. All rights Reserved