Clinical application research on the titanium metal metatarsal prosthesis designed through FEA and manufactured by 3D printing.

Abstract

exploring the therapeutic efficacy of a 3D-printed multiple microporous titanium metatarsal and polyethylene sesamoid prosthesis based on finite element analysis. A patient with defect in the first metatarsal was enrolled. A digital model of the first metatarsal and medial cuneus prosthesis was designed from the contralateral images and the relevant anatomical parameters measured in the preoperative period (Model A). Model B was obtained by finite element analysis and iterative optimization of Model A. Model A and Model B designed with a microporous, an insertion structure for bone ingrowth and fusion, and a polyethylene sesamoid for limb weight-bearing. The object A and object B, made from titanium, were generated by 3D printing. The polyethylene sesamoid was manufactured by computerized numerical control technology. The prosthesis consist of object B and polyethylene sesamoid was implanted into the patient. The clinical parameters were evaluated. The maximum displacements of Model A and Model B were 0.031 mm and 0.019 mm. the deviation of the stress results was controlled within 5% between Model A and Model B. The object A with 63% weighed object B. There is significant difference for pressure in M1 and M5 area between bilateral foot. The AOFAS score was 48 before surgery and 88 after 15 months of surgery. The VAS score of before surgery, after 15 months of surgery and after 27 months of surgery was 7, 2 and 1, respectively. The lightweight and microporous design based on finite element analysis for metatarsal prosthesis, and manufactured by titanium and polyethylene can Reconstruct the arch.