Preparation of nano hydroxyapatite/polyamide composite and its application in lumbar disc herniation operation

Carbon fiber (CFR) was used to strengthen the mechanical properties of hydroxyapatite/polyamide (ha/pa) to synthesize ternary composites with different mass fraction. At the same time, its mechanical and material characterization were compared with that of ha/pa without CFR. CFR-ha/pa was used as the substrate for the culture of mouse bone marrow mesenchymal stem cells (C3H10T1/2). The cell morphology and adhesion properties of materials were analyzed by immuno light staining of cytoskeleton and adhesion protein, and FESEM. The interbody fusion cage based on the material was used in the treatment of lumbar disc herniation. According to the X-ray film and the corresponding scoring standards (JOA, ODI and VAS), the therapeutic effect of the interbody fusion cage was evaluated. The results showed that there were cavities on the surface of CFR-ha/pa composites. With the increase of the mass fraction of CFR in CFR-ha/pa composites, the compressive strength ( from 115 MPa to 218 Mpa), the bending strength (from 85 MPa to 140 MPa) and other mechanical indexes of the composite increased obviously. After 24 h of cell inoculation, the substrate of CFR-ha/pa group was covered by layered, well spread and fused cells, and there was dense cell adhesion around it, that was to say, the material and cells showed good adhesion performance. At the same time, the levels of Integrin alpha 1 and Integrin beta 1 significantly increased in CFR-ha/pa group (P < 0.05). The VAS and ODI scores of polyether ether ketone (Peek) interbody fusion cage group and CFR-ha/pa interbody fusion cage group were lower than those before operation (P < 0.05). The therapeutic effect of CFR-ha/pa interbody fusion cage is better than Peek interbody fusion cage.