Free Fibula Flap for Congenital Pseudarthrosis of the Tibia: Indications and Challenges

Abstract

Background: Congenital pseudoarthrosis of the tibia (CPT) is a rare pathological disease associated with neurofibromatosis type 1 (NF1). It presents with tibial bowing and can progress into a nonhealing fracture. Treatment options include conservative approaches such as serial bracing or various surgical options.Surgically, the aims are to achieve long-term bone union, prevent limb length discrepancies (LLDs), and avoid mechanical axis deviation, soft tissue lesions, nearby joint stiffness, and pathological fracture.The purpose of our study is to highlight our experience with both the conservative approach and the use of vascularized free fibula reconstruction of these deformities, including the challenges encountered with a long-term follow-up until skeletal maturity.

Methods: We present a retrospective analysis of a total of nine (9) patients consisting of three (3) girls and six (6) boys. Six (6) children were treated with a vascularized fibula flap, and the other three (3) were treated conservatively. Outcomes measured included fractures, LLD, ankle valgus deformity, donor site morbidity, and number of surgical corrections.

Results: All patients had flap survival. Three (3) of six children had a previous failed surgery with intramedullary nail and bone graft prior to performing a vascularized free fibula reconstruction. The follow-up period ranged from 8 months to 200 months. The complications included stress fractures (50%), LLD (66.6%), and ankle valgus (33.3%). During growth phases, these children required multiple corrective surgeries.

Conclusions: Fibula free flap is a good treatment option for CPT even in patients with prior surgical failures with variable results.Level of Evidence - Level 4 - Case series Therapeutic Studies-Investigating the Results of Treatment.

Keywords: Congenital Pseudoarthrosis of Tibia; Fibular flap; Neurofibromatosis.

Image A

Preoperative x-ray of a child with CPT.

Image B

Preoperative photograph showing the affected right leg with obvious limb length discrepancy

Image C

Preoperative planning of fibula flap removal from the left leg

Image D

Intraoperative photograph after exposure of the pseudoarthosis of the right tibia

Image E

Specimen after excision of the diseased segment

Image F

Image of the fibula flap after harvest with the buoy flap for monitoring

Image G

Vascularized fibula flap inset into the defect and internally fixed with Recon plate and screw

Image H

Postoperative image of the child with limb length discrepancy corrected

Image I

Postoperative x-ray of the child after the fibula flap procedure.

Figure 1

Initial radiograph of a child who underwent conservative management.

Figure 2

Serial x-ray taken 3 years later of the same child who underwent conservative management—no obvious fracture was observed, and the deformity was manageable.

Figure 3

Serial x-ray taken 4 years after the initial x-ray of the same child—no fracture and the deformity was manageable.