Open Access
CC BY-NC-ND 4.0 · Indian J Plast Surg 2018; 51(03): 274-282
DOI: 10.4103/ijps.IJPS_113_17
Original Article
Association of Plastic Surgeons of India

Free fibula flap for lower limb salvage after tumour resection

Vinay Kant Shankhdhar
ACTREC Tata Memorial Centre, Navi Mumbai, India
,
Prabha S. Yadav
1   Tata Memorial Centre, Mumbai, Maharastra, India
,
Ajay Puri
1   Tata Memorial Centre, Mumbai, Maharastra, India
,
Ashish Kasat
1   Tata Memorial Centre, Mumbai, Maharastra, India
,
Jaiswal Dushyant
1   Tata Memorial Centre, Mumbai, Maharastra, India
,
Ram Badari Narayan Raghu
1   Tata Memorial Centre, Mumbai, Maharastra, India
,
Ashish Gulia
1   Tata Memorial Centre, Mumbai, Maharastra, India
› Author Affiliations
Further Information

Address for correspondence:

Dr. Vinay Kant Shankhdhar
Flat No. 101, Mandavi Building, Anushakti Nagar, Trombay, Mumbai - 400 094, Maharastra
India   

Publication History

Publication Date:
26 July 2019 (online)

 

ABSTRACT

Context: Post-tumour resection lower limb salvage. Aim/Introduction: Resection of tumours of the femur and tibia around the knee and ankle joints results in large bony defects. Often arthrodesis is an alternative; in case, adequate functional motors cannot be preserved or due to economic constraints. Thus, in an immunocompromised patient, the vascularised fibula is the best form of reconstruction. The vascularised fibular flap (pedicled/free) can be used in combination with an allograft. We refer to such a combination reconstruction as ‘allocombo’. The vascularised fibular graft hypertrophies in due course of time, and till that period, the allograft provides the required mechanical strength to allow early ambulation. Subjects and Methods: A retrospective study of 24 cases of vascularised fibular graft for lower limb reconstruction was conducted from February 2003 to March 2014. The average defect size was 15.5 cm and the average length of fibula harvested was 24.35 cm. A total of 19 free fibular flaps and 5 pedicled fibula were done. Mean age was 26 years. Fibula was nestled in the allograft obtained from the tissue bank. Results: The mean follow-up time was 52 months. Free flap success rate was 96%. Successful healing was achieved at 45 ends (97.8%). Radiological evidence of union at osteotomy sites occurred at an average of 6.8 months. Eight patients eventually succumbed to disease. At the final follow-up, the mean Musculoskeletal Tumour Society functional score of the evaluable patients was 26 (range 20–30). Conclusions: Pedicled fibula is a good option if the defect is within 14 cm of the knee joint at the femoral end. The vessels have to curve around the fibular head, thus its removal improves the reach of the pedicle. The flap is easy to harvest with predictable vascular anatomy and it can provide a large amount of vascularised bone and skin paddle. It results in early ambulation, rehabilitation and reduced morbidity. We realised that fixation is easier and chances of vascular injury are less in free as compared to pedicled fibula.


INTRODUCTION

Resection of tumours of the femur and tibia around the knee and ankle joints results in large bony defects.[[1]] While prosthesis offers a reconstructive option,[[2]] often arthrodesis is an alternative; in case, adequate functional motors cannot be preserved or due to economic constraints (for those patients who cannot afford megaprosthesis). In an immunocompromised patient, the potential for infection and non-union increases if a non-vascularised bone graft is used.[[3] [4]] Thus, a vascularised fibula is the best form of reconstruction in such cases. The vascularised fibular flap (pedicled or free) can be used in combination with an allograft. We refer to such a combination reconstruction as ‘allocombo.’ The vascularised fibula provides the potential for biological incorporation and the irradiated allograft offers early mechanical strength. The vascularised fibular graft hypertrophies in due course of time, and till that period, the allograft provides the required mechanical strength to allow early ambulation. The goal of our work was to analyse the results of vascularised fibular graft to bridge the defect resulting after tumour resection.


SUBJECTS AND METHODS

A retrospective study of 24 [[Table 1]] of vascularised fibular graft for lower limb reconstruction was conducted at our centre from February 2003 to March 2014. In 20 cases, resection and reconstruction were done at the same time. Of the remaining four, one was removal of antibiotic spacer; total knee replacement prosthesis removal was done in two cases and in one, removal of the allograft with the plate was done.

Table 1

Overview of cases

Patient

Age (years)

Sex

Intercalary or arthrodesis

Provisional diagnosis

Free or pedicled

Site of tumour

Allograft

Defect

Length of fibula harvested

Type

Advanced/flipped

Surgery done

Primary excision

MSTS score (1 year, last follow-up)

PNET: Pancreatic neuroendocrine tumours, GCT: Giant-cell tumour, OGS: Osteogenic sarcoma, TKR: Total knee replacement, DCP: Dynamic compression plate, W/E: Wide Excision, Local Excision, D/E: Distal End U/E: Upper/End

1

13

Male

Intercalary

PNET

Free C/L

Femur

Yes

16.5

20.5

Removal of AB spacer-free fibula arthrodesis + plating

No

No follow-up

2

14

Male

Ankle arthrodesis

PNET

Free

Tibia

No

10.5

22

W/E+live fibular transfer

Yes

24, 26

3

15

Male

Arthrodesis

OGS

Free C/L

Knee

Yes

16.5

21

Live fibula reconstruction

Yes

Expired

4

16

Male

Intercalary

OGS

Free C/L

Femur

Yes

18.5

23

Knee arthrodesis with double fibular autograft struts

Yes

Expired

5

16

Female

Arthrodesis

GCT

Pedicled

Knee-distal femur

No

10

23

Advanced

Wide excision + pedicle fibula arthrodesis

Yes

28, 30

6

16

Male

Intercalary

OGS

Pedicled

Femur

Yes

12

23

Advanced

TKR removal + pedicled fibula knee arthrodesis + DCP

No

Flap loss, expired

7

18

Male

Ankle arthrodesis

PNET

Free

Tibia

No

8

20.5

Double barrel

W/E + knee arthrodesis + live fibula doubled + Ex fix

Yes

Expired

8

19

Male

Arthrodesis

Osteosarcoma

Free

Femur

Yes

21

26.5

W/E with knee arthrodesis + allograft + plate

Yes

26, 27

9

21

Female

Arthrodesis

GCT

Free

Tibia

No

20

26

Live fibula arthrodesis+flap cover

Yes

No follow-up

10

21

Male

Intercalary

Periosteal OGS

Free

Femur

Yes

18

24.5

Live fibula reconstruction after W/E femur

Yes

Distal nonunion

11

22

Male

Ankle arthrodesis

GCT

Free

Knee-Prx Tib

No

13

26

W/E with live fibula alloarthrodesis

Yes

25, 27

12

24

Female

Arthrodesis

Osteosarcoma

Free

Shaft femur

Yes

21.5

25.5

Wide excision + live fibula allograft combo arthrodesis

Yes

Fracture of allograft

13

26

Male

Arthrodesis

GCT

Free

Femur

Yes

25

28

W/E + knee arthrodesis with allo + live fibula combo

Yes

22, 24

14

28

Female

Arthrodesis

Osteosarcoma

Free

Femur

Yes

21

24.5

W/E + live fibula + plating

Yes

Expired

15

29

Female

Arthrodesis

GCT

Free

Femur

Yes

16.5

24.5

W/E U/E tibia + live fibula arthrodesis

Yes

No follow-up

16

32

Female

Arthrodesis

Chondrosarcoma lt. femur L/E

Free

Femur

No

10

25

Double barrel

Excision + double-barrel live fibular graft + knee arthrodesis

Yes

No follow-up

17

32

Male

Arthrodesis

GCT

Free

Femur

Yes

17.5

26

W/E + live fibula + custom plate

Yes

19, 20

18

33

Female

Arthrodesis

GCT

Pedicled

Femur

No

9.5

25

Flipped

Removal of allograft and plate+live fibula graft and fixation

No

Amputation secondary to disease

19

34

Male

Arthrodesis

OGS

Free

Femur

No

10.5

27

Double barrel

W/E + double-barrel live fibula

Yes

Expired

20

39

Male

Arthrodesis

GCT

Free

Tibia

No

13.5

23

W/E + live fibula arthrodesis

Yes

23, 25

21

39

Male

Arthrodesis

Osteosarcoma

Pedicled

Ankle

No

11.5

26

Flipped

W/E + pedicled fibula + allograft

Yes

27, 30

22

39

Male

Arthrodesis

OGS parosteal D/E femur left

Free

Femur

Yes

18.5

27

Live fibula-allocombo with DCS fixation after removal of implant

No

Expired

23

40

Male

Intercalary

Adamantinoma L/E tibia recurrent

Pedicled

Tibia

No

17.5

26

Flipped

Intercalary excision with live fibula allocombo

Yes

25, 26

24

32

Female

Arthrodesis

OGS parosteal femur

Free

Femur

Yes

15.5

21

Excision + free fibula knee arthrodesis

Yes

Expired

The histopathologic diagnosis was Giant-cell tumour (n = 8), Ewing's sarcoma (n =3), osteosarcoma (n =8), periosteal tumour (n =3) chondrosarcoma (n =1) and adamantinoma (n =1). Eight were female and 16 were male with the mean age of 26 years (range: 13–40 years). The average defect size was 15.5 cm (minimum of 8 cm and a maximum of 25 cm) and the average length of the fibula harvested was 24.35 cm (minimum = 20.5 cm and maximum = 28 cm). The length of fibula harvested is always much more than the defect. Harvesting long length of fibula ensures easier dissection of the peroneal pedicle, thus longer pedicle length. Nineteen free fibular flaps (FFFs) and five pedicled fibula were done. Double-barrel fibula was done in three cases. Wherever double barrel was possible, it was preferred over allograft as it provides more vascularised bone stock. If the defect is small about 8–10 cm and pedicle length required is not much, only then double barrel is possible. For double barrel, distal segment has to flip up. For this, we need to excise at least 2 cm of bone for smooth curving of the pedicle. However, a combination of double barrel and allograft is not possible due to space constraints.

Intercalary reconstruction was done for 5 cases and arthrodesis for 19 cases (3 for ankle and 16 for knee). For ankle arthrodesis, free fibula was always used. Advancement of fibula distally towards the ankle results in traction of the peroneal vessels. Suitable internal fixation using a combination of plates, screws and K-wires was used to stabilise the construct Suitable strut allografts were obtained from the hospital tissue bank.[[5]]

Preoperatively, the site, size and involvement of the soft tissues were assessed in consultation with the orthopaedic colleagues. For defects within 14 cm above the knee joint, we planned pedicled fibula and free for defects beyond this. For segmental defects of the tibia, tibialisation of the fibula was done, but we have not included those cases for the present study.

Pedicled fibula

Harvest of the fibula flap

The reach of pedicled fibula is comfortable for 14 cm defects above the knee joint. Posterior tibial artery division improves the reach in larger defects. The posterior tibial artery was divided only in one case of the total five pedicled cases (20%), as the pedicled fibula was just falling short by 1 cm. The division of posterior tibial artery improved the reach proximally by about 2 cm as now, the pivot point shifted to the origin of the anterior tibial artery. No pre-operative angiography was done in this case; however, vascular clamps were applied for 20 min on the posterior tibial artery before its division to ascertain the limb vascularity. In other pedicled cases, division of posterior tibial artery was not required as the reach was adequate even without its division.

After the excision of the tumour, the fibula flap was harvested using the standard anterior approach. The ipsilateral fibular head increases the pedicle length requirement in the pedicled fibula, as the vessels have to curve around it. Thus, fibular head is also harvested (taking care to preserve the common peroneal nerve) with fibula providing with a longer bone and in all cases when pedicled fibula is used, it reduces the bulk on the lateral aspect of the knee and improves the reach. The fibular flap was harvested with the head of the fibula along with the maximum length of the fibula available leaving behind 6 cm of the fibula close to the ankle joint. The peroneal vessels are divided at the lower end.

The fibula can be transposed in the defect by either advancing (the upper end of the fibula reaches the upper end of the defect) or by flipping it 180° [[Figure 1a-c]], so that the lower end of the fibula reaches the upper part of the defect. Flipping improves the reach of the fibula in the upper defects. Pedicled fibula was advanced in two cases (40%) and flipped in three cases (60%). The fibular head was excised in all cases of pedicled fibula as it reduces the arc of rotation of the peroneal vessels carrying the fibula.

Zoom
Figure 1: Pedicled fibula being transposed to a defect in the femur. (a) Line diagram to show fibula being advanced and flipped 180°. (b) Pedicled fibula harvested and being flipped 180° to reach defect in the femur. (c) Fibula flipped 180° to reach the defect

Allo-fibula fixation

One side of the allograft cortex is removed to enable fibula to nestle in the allograft [[Figure 2]]. The length of allograft required is equal to the defect size and the fibula projects out 1 cm on either side so that it can be pegged in the medullary cavity of the femur and/or tibia [[Figure 3a and b]]. The allograft is fixed using plate and screws, and the fibula is secured using K-wire fixation [[Figure 4]].

Zoom
Figure 2: Irradiated and non-antigenic tibial allograft obtained from the bone bank. The allograft is reamed to create a slot for the fibula
Zoom
Figure 3: (a) Fibula fixed in the slot of allograft with both fibular ends projecting out to be pegged into the femur on both sides of the defect. (b) The fibula+allograft in the defect
Zoom
Figure 4: Allocombo fixed with plate and screws and both ends of the fibula pegged in the medullary cavity of the femur and/or tibia

Free fibula with allograft

In cases where the ipsilateral fibula is not available or where the defect is too high up or where the knee joint is not sacrificed, it is usually not possible to use pedicled fibula and then either ipsilateral fibula or contralateral fibula as a free flap is used. The entire procedure remains the same except that microvascular anastomosis is required. The recipient vessels may be descending branch of the lateral circumflex femoral vessels most of the times. Descending branch of the lateral circumflex femoral vessels are the vessels which supply anterolateral aspect of the thigh and is frequently harvested with the anterolateral thigh flaps, thus a relatively constant, familiar and easy to dissect the vessel. It lies just behind the rectus femoris muscle. Even femoral vessels with end-to-side anastomosis using saphenous vein graft were required in four cases.

In two cases, pedicled fibula was converted into the free vascularised flap. In one case, during fixation of the fibular flap, the peroneal vessel avulsed and anastomosis was then done with the anterolateral thigh flap pedicle. In a second case, the vessel was getting compressed with the femoral condyle and developed a thrombus in the vessels. A venous graft was required and anastomosis was done end-to-side with the femoral vessels.



Statistical methods

Shapiro–Wilk test was used to check the Musculoskeletal Tumour Society (MSTS) Scores. It was normally distributed. The MSTS scores improved over time as checked by the paired t-test (P < 0.0001). The Statistical Package for the Social Sciences software (Version 25, IBM SPSS Corp., Armonk, NY, USA) was used for statistical analysis.



RESULTS

The mean follow-up time was 52 months (28 months to 109 months). In three cases, skin paddle necrosis was observed but no fibular loss. Of the total 24 vascularised fibula flaps (VFFs), one flap was lost due to vascular compromise secondary to infection, resulting in amputation. This patient later died due to the disease.

Thus, free flap success rate was 96%. One patient required additional bone grafting for distal non-union in a total of (23 × 2 = 46) bone ends. Successful healing was achieved at 45 ends (97.8%). Guarded partial weight-bearing using walking assists started once evidence of bony union started. It is averaged at about 3-month post-operative. The patient was referred to physiotherapist for proper training of partial weight-bearing. It was progressed to eventual full weight-bearing over the next 6–8-week time. Radiological evidence of union [[Figure 5]] at osteotomy sites occurred at an average of 6.8 months (5 months to 23 months). In one patient, 2 years after the allocombo surgery, the allograft had not incorporated, but both the superior and inferior osteotomy sites had united, thus the patient was allowed weight-bearing. The vascularised fibular graft had a segmental fracture; this patient required amputation secondary to recurrence.

Zoom
Figure 5: X-ray showing radiological union 1-year post-operative

Eight patients eventually succumbed to disease. Two were local recurrences. At the final follow-up, the mean of MSTS’ functional score of the evaluable patients was 26 (range: 20–30). We had prepared two tables for MSTS score, one at 12 months and one at the final follow-up. MSTS score had improved [[Table 2]].

Table 2

The musculoskeletal tumour society scores over time

12 months

Follow-up

P

24.33±2.74

26.11±3.06

<0.0001


DISCUSSION

The options available after excision of extremity bony tumours are either amputation or limb salvage.

Limb salvage is currently the procedure of choice, as it has been proven that the oncologic outcome is not compromised and the quality of life is much superior as compared to amputation.[[6]]

Involvement of major neurovascular bundles, massive soft-tissue resections or severe infections are relative contraindications for limb salvage.[[7]]

Knee prosthesis is the ideal reconstructive option,[[8]] but often due to the massive resections, endoprosthesis is not possible and arthrodesis is an alternative option to give a stable, durable and pain-free reconstruction.[[3] [4]]

The Ilizarov technique is another option to deal with such defects, but time required and requirement of chemotherapy in patients restrict the use of this technique. In this subset of patients, pin-tract infections and interference with callus formation are frequent due to aggressive chemotherapy.[[9]]

Capanna first reported the use of allograft combined with autologous fibular flap for lower extremity reconstruction after tumour resections. Vascularised fibula alone is too weak to allow early ambulation and intercalary allograft alone leads to delayed union, non-union or fractures, thus a combination of the two solves the problem. The outer shell of the allograft provides the mechanical strength required for weight-bearing and the inner core of the vascularised fibula provides for the vascularity, thus ensuring good healing.[[9]]

Belt P.J. and Dickinson I.C. reported that the complication rates with allograft alone were high and the allograft non-union rate was 50%; they further noted that the FFF hastens time to full weight bearing but does not appear to affect the complication rates of the allograft.[[10]] The allograft with VFF union rate in our series was 97.8%. In our series, eight patients succumbed to disease and four were lost to follow-up. A total of three bone complications (one flap loss, one distal non-union and one segmental fracture) occurred of the total 13 patients with long-term follow-up. The complication rate thus came to 23%. Further, in the series by Belt and Dickinson, the mean time to full–weight-bearing in the lower limb cases was 7.5 months and 100% were full-weight-bearing at 18 months. Whereas in our study, guarded partial weight-bearing using walking assists progressed to eventual full-weight-bearing once evidence of bony union was seen on radiographs. Standard biplanar radiographs were assessed. Bridging across three of four cortices in biplanar radiographs was considered evidence of union at an average of 6.8 months (5 months to 23 months). Please refer [Table 3] for Comparison of various factors with other studies and [Table 4] for Kaplan–Meier survival chart

Table 3

Comparison of various factors with other studies

Studies diseasefree survival (years)

Number of patients

Mean followup (years)

Mean defect length (cm)

MSTS score (%)

Complication rate (%)

MSTS: Musculoskeletal Tumour Society, NR: Normal range

Zaretski et al.[[11]]

30

2.5

NR

-

37

Krieg et al.[[12]]

16

1.0

16.2

85

-

Eward WC et al.[[13]]

30

4.9

14.8

-

53

Rabitsch et al.[[14]]

12

3.2

18.7

-

50

Parag et al.[[15]]

10

3.1

18.5

86.6

50

Our study

24

4.3

15.5

87

23

Table 4

Kaplan-Meier survival chart

Case processing summary

Total n

Number of events

Censored, n (%)

24

8

16 (66.7)

Survival Table

Time

Status

Cumulative proportion surviving at the time

Number of cumulative events

Number of remaining cases

Estimate

SE

SE: Standard error

1

13.996

1.00

0

23

2

26.218

1.00

0

22

3

35.055

2.00

1

21

4

35.055

2.00

0.909

0.061

2

20

5

36.468

2.00

0.864

0.073

3

19

6

45.700

2.00

0.818

0.082

4

18

7

55.195

2.00

0.773

0.089

5

17

8

59.893

1.00

5

16

9

59.926

1.00

5

15

10

61.405

1.00

5

14

11

63.770

2.00

0.718

0.099

6

13

12

69.947

1.00

6

12

13

74.251

1.00

6

11

14

90.875

1.00

6

10

15

95.211

1.00

6

9

16

96.131

1.00

6

8

17

100.665

1.00

6

7

18

101.027

2.00

0.615

0.127

7

6

19

104.936

2.00

0.513

0.141

8

5

20

108.977

1.00

8

4

21

111.507

1.00

8

3

22

111.540

1.00

8

2

23

113.117

1.00

8

1

24

161.248

1.00

8

0


CONCLUSIONS

Pedicled fibula is a good option if the defect is within 14 cm of the knee joint at the femoral end. In cases where the tibial condyles are also excised due to oncological reasons, the reach of pedicled fibula is more as compared to cases in which the tibial condyles are spared. This helps in planning for a pedicled or free fibula. Furthermore, the ipsilateral fibular head increases the pedicle length requirement in pedicled fibula as the vessels have to curve around it, so it is important to remove the fibula head taking care to preserve the common peroneal nerve. The flap is easy to harvest with predictable vascular anatomy and it can provide large amount of the vascularised bone and skin paddle. It results in early ambulation, rehabilitation and reduced morbidity. In our experience, we realised that fixation is easier and chances of vascular injury are less in free as compared to the pedicled fibula.

Financial support and sponsorship

Nil.

Zoom



Conflicts of interest

There are no conflicts of interest.

Acknowledgement

The authors would like to thank Mr. Nilesh Ganthade, Medical Graphics Department, Tata Memorial Hospital, Mumbai


Address for correspondence:

Dr. Vinay Kant Shankhdhar
Flat No. 101, Mandavi Building, Anushakti Nagar, Trombay, Mumbai - 400 094, Maharastra
India   


Zoom
Figure 1: Pedicled fibula being transposed to a defect in the femur. (a) Line diagram to show fibula being advanced and flipped 180°. (b) Pedicled fibula harvested and being flipped 180° to reach defect in the femur. (c) Fibula flipped 180° to reach the defect
Zoom
Figure 2: Irradiated and non-antigenic tibial allograft obtained from the bone bank. The allograft is reamed to create a slot for the fibula
Zoom
Figure 3: (a) Fibula fixed in the slot of allograft with both fibular ends projecting out to be pegged into the femur on both sides of the defect. (b) The fibula+allograft in the defect
Zoom
Figure 4: Allocombo fixed with plate and screws and both ends of the fibula pegged in the medullary cavity of the femur and/or tibia
Zoom
Figure 5: X-ray showing radiological union 1-year post-operative
Zoom