The rutile structure titanium oxide (Ti-O) film was prepared on the pure titanium material TA2 (99.999%) surface by the magnetic filter high vacuum arc deposition sputtering source. The method can not only maintain the material mechanical properties, but also improve the surface properties for better biocompatibility to accommodate the physiological environment. The preparation process of the Ti-O film was as follows. Firstly, argon ions sputtered to the TA2 substrate surface to remove the excess impurities. Secondly, a metal ion source generated Ti ions and oxygen ions by the RF discharge. Meanwhile a certain negative bias was imposed on the sample. There a certain composition of Ti-O film was obtained under a certain pressure of oxygen in the vacuum chamber. Finally, X-ray diffraction was used to research the structure and composition of the film. The results showed that the Ti-O film of the rutile crystal structure was formed under the 0.18 Pa oxygen partial pressure. A Nano scratch experiment was used to test the coating adhesion property, which demonstrated that the film was stable and durable. The contact angle experiment and the platelet clotting experiment proved that the modified surface method had improved platelet adhesion performance, and, therefore, the material possessed better biocompatibility. On the whole, the evaluations proved the modified material had excellent performance.
ObjectiveTo investigate the effect of preoperative valgus or varus deformity on the prosthesis installation and alignment restoration in total knee arthroplasty (TKA). MethodsBetween January 2012 and December 2013, 198 patients (245 knees) with osteoarthritis underwent primary TKA, and the clinical data were retrospectively analyzed. There were 23 males and 175 females, with the average age of 67 years (range, 43-90 years). Single knee and double knees were involved in 151 and 47 cases respectively. The disease duration was from 1 month to 30 years (mean, 8.99 years). The anteroposterior X-ray films of whole lower limbs were taken, and the femorotibial angle (FT) was measured before operation and at 1 week after operation; the mechanical femoral angle (MF) and the anatomical tibial angle (AT) at 1 week after operation were measured. The correlation analysis was made for pre-and post-operative FT, MF, and AT. According to the valgus or varus deformity before operation, all patients were divided into 5 groups:≥20° varus (group A), 10-20° varus (group B), ≤10° varus (group C), < 10° valgus (group D), and≥10° valgus (group E), and the above indicators were compared between groups. And the rate of the good limb alignment was recorded after operation. ResultsThe pre-and post-operative FT were (171.53±9.12) and (177.38±3.57)° respectively, and postoperative MF and AT were (89.00±2.68) and (88.62±2.16)° respectively. Preoperative FT was associated with postoperative FT and MF (r=0.375, P=0.000; r=0.386, P=0.000), but it was not correlated with AT (r=0.024, P=0.710). Postoperative FT was associated with MF and AT (r=0.707, P=0.000; r=0.582, P=0.000). Postoperative FT was significantly increased when compared with preoperative FT in each group (P < 0.05). There were significant differences in preoperative FT between groups (P < 0.05). There were significant differences in postoperative FT when compared group A with groups B, C, D, and E (P < 0.05), and when compared groups B and C with groups D and E (P < 0.05), but there was no significant difference between groups B and C, and between groups D and E (P>0.05). The rate of good alignment was 70.2% (172/245); it was 27.8% (5/18), 66.0% (62/94), 74.4% (67/90), 88.9% (32/36), and 85.7% (6/7) in groups A, B, C, D, and E respectively, showing significant differences between groups (P < 0.05). There was no significant difference in postoperative AT between groups (P>0.05). Except for between group D and group E (P>0.05), significant difference in MF was shown between the other groups (P < 0.05). ConclusionThe more severe deformity of lower limb before TKA, the higher risk of deviation for prosthesis installation and poor alignment in TKA.
ObjectiveTo investigate the influence of the degree of acetabular deformity and the learning-curve on the acetabular cup positions in total hip arthroplasty (THA) for adults with developmental dysplasia of hip (DDH). MethodsBetween January 2008 and December 2015, 130 patients (144 hips) with DDH underwent primary THA, and the clinical data were analyzed retrospectively. Fifty-three patients (59 hips) were admitted before 2012, and 77 patients (85 hips) were treated after 2012. There were 32 males and 98 females, aged from 31 to 83 years (mean, 61). Unilateral replacement was performed in 116 cases and bilateral replacement in 14 cases. Of 144 hips, 48 hips were rated as Crowe type I, 57 hips as type II, and 39 hips as type of III/IV. The standard pelvic radiograph was taken within 1 week after operation. The mediCAD software was adopted to measure the angle of anteversion and abduction, bony coverage, and the distance between true rotating center and optimal rotating center to the connection of teardrops and the horizontal distance between two centers to evaluate the qualified rate of acetabular cup positions. ResultsCompared with the patients with the same type in 2013-2015 group, the anteversion angle and qualified rate of acetabular cup position significantly decreased in patients with Crowe I (P < 0.05); the horizontal distance significantly increased and qualified rate of acetabular cup position significantly decreased in patients with Crowe II (P < 0.05); and the anteversion angle significantly decreased and the horizontal distance significantly increased in patients with Crowe III/IV (P < 0.05) in 2008-2012 group. But no significant difference was shown in the other indexes (P > 0.05). In all Crowe types, the vertical distance between the true rotating center and the optimal rotating center increased with the degree of acetabular deformity in both 2008-2012 group and 2013-2015 group, showing significant difference (P < 0.05), but no significant difference was found in the other indexes (P > 0.05). ConclusionFor adults with acetabular dysplasia, there are high potential risks for unsatisfactory acetabular cup positions during primary THA. So it is necessary to evaluate acetabular deformities and to sum up operative experience so as to improve the accuracy of cups installation.