To explore the feasibility and effectiveness of the digital three-dimensional reconstruction methods in visualization and clinical application for the saphenous neurocutaneous flap.

One resh cadaver was subjected to spiral CT scanning before and after the radio-opaque material infused by the femoral artery.The bones, muscles, fascia, skin and vessels were reconstructed by the Mimics 10.01, and the single artery and its branches were gained by the subdivision of the vessels. 3D-images were shown respectively and combinedly to design and cut the saphenous neurovascular flap.The study on the basis of above included 40 patients with soft tissue defects of the ankle and foot who underwent soft tissue reconstruction between December 2015 and January 2018. The patients were randomly assigned into two groups (A, B) (n=20 cases), digital reconstruction preoperative was performed in group A, but was not performed in group B. Two groups were compared with postoperative saphenous neurocutaneous flap survival rate, operation time, accuracy and distance of flap rotation to the medial malleolus vertex.

Bones, muscles, fascia and skin were easy to be reconstructed from the data which was scanned before the infusion, and the vessels were easy to be reconstructed from the data after the infusion.The vessels and soft tissue displayed in the software could show detailed distribution of the vessels in one region and this could provide the accurate anatomical basis for the saphenous neurocutaneous flap and the design of the operation.Group A of saphenous neurocutaneous flap after reconstruction of digital and could show flap blood supply and be able to clearly show the skin, muscle, and three-dimensional vascular anatomy; application of software comes with measurement tools to measure the blood vessels, the flap could be accurately positioning the guidance of the surgical procedure. Blood for intraoperative exploration and reconstruction of the image match, accurate positioning of the body surface. All flaps in Group A survived and the recipient site primarily healed, but 4 flaps in Group B had marginal necrosis after the operation. During the 3-12 month follow-up period, all flaps in Group A had good skin quality. In Group B, hard scarring and mild contracture occurred in 6 cases, and the patients experienced pain when walking. The survival rate of the flap in Group A (100%) was significantly higher than that in Group B (70%), the difference was statistically significant (P<0.05). The operation time in Group A[(114.05±10.36) min]was significantly less than that in Group B [(123.20±11.91)min], the difference was statistically significant (P<0.01). The surgical accuracy in Group A(0.17±0.03) was significantly better than that in Group B(0.23±0.02), the difference was statistically significant (P<0.01). The distance of flap rotation to the medial malleolus vertex in Group A[(4.14±0.38) cm] was significantly shorter than that in Group B[(5.96±0.81) cm], the difference was statistically significant (P<0.01).

The method of three-dimensional reconstruction is very good for the design of the operation. The preoperative use of three-dimensional digitalized virtual planning for the saphenous neurocutaneous flap obtains a satisfactory therapeutic effect in repair of soft tissue defects in the ankle and foot.It is worthy of clinical popularization and application.