Precision evaluatation of personalized knee osteotomy instrument based on 3D printing technology for the total knee arthroplasty / 局解手术学杂志

ABSTRACT

Objective To construct a personalized knee osteotomy instrument(POI)based on 3D printing technology for the total knee arthroplasty(TKA)and to evaluate the precision of POI.Methods The full-length CT scanning and MRI scanning of the affected lower limbs were performed before operation respectively.The data fusion of CT scanning and MRI scanning were performed with the 3D anatomical data,and then the articular cartilage were reconstructed.The force lines were measured with virtual personalized osteotomy,and TKA prosthe-sis installation were calculated by CAD software.Based on CAD mimic,the registration surface of POI for femoral condyle and tibial plateau were designed by Boolean Subraction calculation technique.The shape and limit structure(LS)of POI were designed according to the regis-tration surface and the osteotomy surface.Finally,POI were fabricated by FDM 3D printing technology.Femoral condylar POI and tibial plat-eau POI were manufactured 15 cases in each group.The difference between design and actual values(DDA)of POI and LS size were meas-ured with the DDA of DML calculated.And the deviation of the TKA prosthesis angle from the design value was measured to verify the precision of the osteotomy of POI.Results There was no significant difference in the shape of POI and LS between design and actual values(P>0.05). Moreover,there was no significant difference of DMLs(P>0.05).Meanwhile,there was no significant difference of TKA prosthesis angle be-tween the design and postoperative values(P>0.05).Conclusion 3D printing technique can accurately construct the POI of TKA.POI can accurately register the articular surface and guide the osteotomy in TKA,which is conducive to the precision of TKA operation.