Clinical Application Of 3-D Printing Technology In Total Hip Arthroplasty

Objective: To explore the application value of 3-D printing technique in total hip arthroplasty(THA)of severe hip deformity,so as to select a more appropriate and accurate way for artificial total hip arthroplasty,and to provide a new method for evaluation of posterior hip surgery.To evaluate the consistency of MRI and CT in the measurement of femoral neck enteversion in developmental dysplasia of the hip(DDH).Methods: Three-dimensional operation simulation process and the manufacturing method of biotype hip 3-D prosthesis were used in this study.Total hip arthroplasty(THA)were used in the treatment of 74 severe hip joint deformity cases from 2015.01-2016.12.Bioprosthesis artificial hip joint were used in both conventional hip arthroplasty and 3-D printing hip arthroplasty cases.Operation time,intra-operative blood loss,post-operative weight-bearing time,Harris score after operation,complication after surgery and the main angle measurement of dual sides of patients were evaluated for the short-term efficacy of 3-D printing prosthesis and common hip prosthesis.MRI and CT were used to measure the consistency of femoral neck anteversion in developmental dysplasia of the hip,to evaluate the accuracy,reliability and repeatability of CT and MRI.Results: A total of 74 patients(57 cases in general hip replacement group and 17 cases in 3-D printing hip replacement group)were followed up for an average of 24 months.3-D printing technology used in preoperative design and 3-D prosthesis production,had shortened Operation time,intra-operative blood loss,postoperative weight-bearing time,improved the Harris score in 2 years after operation,which was significantly different(P<0.05).There was no significant difference in femoral neck anteversion angle,neck shaft angle,acetabular angle and Sharp angle between the ipsilateral and contralateral sides of the 3-D printing group,which was not statistically significant(P>0.05).The femoral neck anteversion angle was significant in common hip replacement group(P<0.05),and there was no significant difference in the other angles(P>0.05)in this group.CT and MRI were consistent with the measurement of femoral neck anteversion(FNA).The cionsistensy inter-observer and intra-observer were higher than that of MRI.Conclusion: Digital design and 3-D printing technology created virtual and realistic simulation and personalized operation plan for patients with severe hip deformity,which was helpful for clinical surgery treatment.3-D printed hip prosthesis was more consistent with the physiological structure and anatomical characteristics of patients,which provided a new method for doctors on acetabular prosthesis selection.CT was more accurate and reliable than MRI in measuring femoral neck anteversion in diagnosis of developmental dislocation of the hip.