Fibula Free Flap Reconstruction – Case Study 2

CMF Case Study 2 - Fibula Free Flap Reconstruction 1

Overview

In this case, 3DLP worked with surgeon Satheesh Prabhu from the Churchill Hospital in Oxford to assist with a patient’s complex mandible reconstruction following osteoradionecrosis (bone death as a result of cancer treatment). In this fibula free flap surgical reconstruction, the patient’s fibula was removed, reshaped and subsequently used to re-construct their jaw. 3D printed guides were designed and manufactured by 3DLP for the fibula and mandible to indicate the cutting planes and a titanium 3D printed implant was permanently fixed to their mandible.

Segmentation

3DLP received the CT scans of the patient’s head, and using advanced medical segmentation software,  reconstructed in 3D the anatomical regions of interest of the patient: the maxilla, mandible, inferior alveolar nerve and teeth. In addition, using an angioscan of the patients leg, 3DLP  segmented the fibula (including vessels) in order to aid planning and guide design/manufacture.

CMF Case Study 2 - Fibula Free Flap Reconstruction 2
CMF Case Study 2 - Fibula Free Flap Reconstruction 3

Virtual Simulation

The 3D reconstruction / segmentation of the patient’s anatomy from the CT scan was used to virtually plan the surgery in order to aid with the surgeon’s pre-surgical planning process. The section shown in red highlights the bone determined by the surgeon to be resected. This part is removed virtually and replaced by the patient’s own fibula (To ensure ankle and knee stability, 60mm of bone are left on each side of the fibula). The reconstruction is virtually performed by shaping the fibula into a new mandible (in this case, two fibula parts are used).

Design Of Patient Specific Devices

After completion of the virtual surgery, patient-specific devices were designed based on the virtual simulation. Three guides were designed: 2 resection guides to aid with accurately removing the mandible and a further guide to similarly aid with removing the patient’s fibula. The fibula guide allowed the surgeon to more precisely remove and cut the straight fibula bone into a curved shape to match the anatomy of the mandible. This is possible thanks to the virtual simulation of the surgery previously performed. Using the fibula guide, 2 fibula parts are extracted from the bone used to  replace the missing part of the mandible (that was removed during the surgery).

In order to secure the fibula bone segments together and with the remaining parts of the mandible, a patient-specific reconstruction plate was designed and 3D printed in Titanium.  Without the use of 3D technologies,  the surgeon would have to bend a straight metal plate to fit the reconstruction – a time consuming exercise which can  compromise the success of the surgery ,as while the plate is being shaped the fibula bone is not supplied by blood – the use of a pre-designed and manufactured patient specific plate overcomes this potential dangerous situation.

CMF Case Study 2 - Fibula Free Flap Reconstruction 4
CMF Case Study 2 - Fibula Free Flap Reconstruction 5

Outcome

The mandible and fibula patient specific guides were 3D printed using a medical grade Nylon polymide. The mandible plate was 3D printed using Titanium. All devices were sterilised by the hospital prior to surgery using Autoclaving.

Without the use of 3D technologies,  the surgeon would have to bend a straight metal plate to fit the reconstruction – a time consuming exercise which can  compromise the success of the surgery ,as while the plate is being shaped the fibula bone is not supplied by blood – the use of a pre-designed and manufactured patient specific plate overcomes this potential dangerous situation.

In this case, the surgery was a success and both the guides and implants fitted perfectly with no further adaption required during the procedure.