The Vascularized Fibula as Salvage Procedure in Extremity Reconstruction: A Retrospective Analysis of Time to Heal and Possible Confounders

Abstract

The vascularized fibula transfer is a well-established technique for extremity reconstruction, but operative planning and patient selection remains crucial. Although recently developed techniques for bone reconstruction, such as bone segment transfer, are becoming increasingly popular, bone defects may still require vascularized bone grafts under certain circumstances. In this study, 41 cases, 28 (68%) men and 13 (32%) women (median age: 40 years), were retrospectively analyzed. Therapy-specific data (flap vascularity [free vs. pedicled] size in cm and configuration [single- vs. double-barrel], mode of fixation [internal/external]) and potential risk factors were ascertained. Indications for reconstruction were osteomyelitis at host site (n = 23, 55%), pseudarthrosis (n = 8, 20%), congenital deformity (n = 6, 15%), traumatic defect, and giant cell tumor of the bone (n = 2, 5% each). Complete healing occurred in 34 (83%) patients after a median time of 6 months. Confounders for prolonged healing were female gender (p = 0.002), reconstruction in the lower limb (p = 0.011), smoking (p = 0.049), and the use of an external fixator (p = 0.009). Six (15%) patients required secondary limb amputation due to reconstruction failure, and one patient had persistent pseudarthrosis at last follow-up. The only risk factor for amputation assessed via logistic regression analysis was preexisting PAOD (peripheral artery occlusive disease; p = 0.008) The free fibula is a reliable tool for extremity reconstruction in various cases, but time to full osseous integration may exceed six months. Patients should be encouraged to cease smoking as it is a modifiable risk factor.

Keywords: bone graft; extremity reconstruction; gender disparities; healing time; microsurgery; osseous incorporation; outcome; vascularized fibula graft.

Figure 1

Schematic illustration of the fibula flap. The fibula (1) is harvested with the nourishing peroneal vessels (2), and for optimal periosteal perfusion, usually a small muscular cuff (3) is included. If needed, the lateral intermuscular septum with its perforating vessels (4) is harvested with the flap, upon which a skin island (5) can be based. In the case of free fibula transfer, the peroneal vessels are re-anastomosed at the recipient site. In the case of pedicled transfer, the fibula remains in the donor leg and is used for tibial reconstruction. The vascular pedicle is transected either distally or proximally to obtain a proximally or distally pedicled fibula graft.

Figure 2

Time to heal in months. Censored cases are patients that required secondary amputation of the limb.

Figure 3

Time to heal in months for male (red) and female (blue) gender. Note that amputations (censored cases) were only performed in male patients.

Figure 4

Time to heal in non-smokers (blue) and smokers (red).

Figure 5

Time to heal in upper (blue) and lower (red) limbs. Note that amputations (censored cases) only had to be performed in lower limbs.

Figure 6

Time to heal in months for patients treated with (red) and without (blue) external fixator. Note that amputations (censored cases) were more frequently performed in patients with external fixator.