A clinical study on hydroxyapatite coated external fixation pins

摘要

The purpose of this study was to compare the biomechanical and clinical results of two groups of patients who underwent external fixation with tapered uncoated or tapered hydroxyapatite coated pins. twenty-four patients from were randomized to receive uncoated (standard), tapered 5/6-millimeter pins (Group A) or hydroxyapatite coated, tapered 5/6-millimeter pins (Group B). Group A had 12 patients; 2 patients had external fixation in the femur and 10 in the tibia. Group B had 12 patients; 2 patients had external fixation in the femur and 10 in the tibia. Mean final insertion torque was 408+-251 Ncm in Group A and 301+-177 Ncm in Group B, (p=0.032). Mean extraction torque was 132+-177 Num in Group A and 579+-260 Ncm in Group B, (p<0.001). In Group A, the extraction torque was significantly lower compared to the corresponding insertion torque (p<0.001). In Group B, the extraction torque was significantly higher compared to the corresponding insertion torque (p<0.001). Group A had 20 pin track infections while Group B had 13 pin track infections (p<0.05). This study demonstrated that coating pins with hydroxyapatite was clinically effective in improving the bone pin interface strength of tapered pins. These results are due to the superior HA coating osteoconductivity and optimal surface roughness which improves initial mechanical stability.