Surface lubricity is one of the important performance criteria for interventional guide wire. In this paper, a review of the methods of surface hydrophilicity and lubrication modification of interventional guide wire is presented, including their fundamental principles, effects and some relative applications. These methods all have their own advantages and disadvantages, therefore, limitations of experimental conditions need to be taken into account.
Catheterization ; Hydrophobic and Hydrophilic Interactions ; Lubrication

Metal-on-metal (MoM) total hip replacement (THR) and hip resurfacing have an advantage of low wear rate and greater stability by larger head size and different characteristics of wear mechanism, tribology, lubrication or generating wear debris compared to conventional metal-on-polyethylene THR. Although the mid- or long term clinical reports of second generation MoM THR were excellent, concerns about local and systemic effect by metal particles or metal ions were remained. Recently, reports have emerged of abnormal soft-tissue reactions to metal particles or metal ions and some hip resurfacing implants were expelled from the market due to high revision rate. This article includes the history of MoM THR, tribology, the biologic effect of metal particles and ions, the clinical results of MoM THR and the issues regarding the problems associated with hip resurfacing.
Arthroplasty, Replacement, Hip* ; Head ; Hip ; Ions ; Lubrication

PURPOSE: This study aimed at investigating the role of albumin as a boundary lubricant in the lubrication of the Co-Cr femoral head of artificial hip implants by measuring the tribological parameters of the Co-Cr femoral head with Atomic Force Microscope (AFM) techniques. MATERIALS AND METHODS: Samples were prepared from the main wear region of a Co-Cr femoral head from revision hip surgery. Two types of solutions were prepared as lubricants: PBS (Phosphate Buffered Saline) as a control solution and BSA (Bovine Serum Albumin) as a lubricant at concentrations of 10, 20, 30 and 40 mg/ml in PBS solution. RESULTS: There were statistically significant differences in the frictional coefficients (micron) of a Co-Cr head between the PBS control and all the concentrations of BSA (10, 20, 30, 40 mg/ml) (P<0.001). Similarly, there were statistically significant differences for the micron between the BSA concentrations of 10, 20, 30 and 40 mg/m for all the cases except between the BSA of 30 and 40 mg/ml (P<0.01). CONCLUSION: There exists a maximum protein concentration of BSA to play a role as an effective boundary lubricant through adsorption on the surface of Co-Cr femoral head.
Adsorption ; Arthroplasty ; Friction ; Head ; Hip ; Lubrication

Lubrication coating is widely used to reduce the friction between the interventional devices and the blood vessels, improves the surface biocompatibility of the interventional device, and also brings the coating stability problems and related risks. This paper describes the coating-related content from the equipment description, performance verification, technical requirements, etc., to reduce the risk of the coating to an acceptable level.
Catheters ; Coated Materials, Biocompatible ; Friction ; Lubrication

The wear debris of ultra-high molecular weight polyethylene (UHMWPE) used as a bearing material in total joint arthroplasty evokes a serious adverse biological reaction (osteolysis). In this study, therefore, the wear resistance of UHMWPE is enhanced by attaching a hydrophilic graft on the UHMWPE surface and by improving surface hardness without deteriorating the mechanical properties, which may result in the formation of lubrication film and the increased resistance to penetration, scratching or deformation during articulation. This was done by ion-implantation technique. The results showed that the wettability and the surface hardness of the modified UHMWPE by the above treatments increased due to the increased cross-linking density and hydrophilic graft attachment on the surface. The wear test was performed by a wear testing machine of pin-on-disk type. The modified UHMWPE revealed about 30~50% less volumetric wear than the control specimen. It was also shown that the volumetric wear depended not only on the optimal treatment condition but on the applied load and the sliding speed.
Arthroplasty ; Hardness ; Joints ; Lubrication ; Molecular Weight* ; Osteolysis ; Polyethylene* ; Transplants ; Wettability

PURPOSE: The aim of the present study was to evaluate the different features of such instruments and how they cause ocular fatigability. METHODS: Under the same settings and circumstances, 75 participants were asked to read the novel, "You without me?" in different formats including paper book, E-book (biscuit(R), Interpark Inc., LG INNOTECK LTD, Korea) and LCD reader (iPad(R), Apple Inc., United States). For every 10 minutes of reading, 10 minutes of rest was provided. After finishing the novel, the participants were asked to complete a questionnaire, and the data obtained were statistically analyzed using univariate analysis. RESULTS: Compared to paper book readers (1.93), LCD readers (2.40) complained of insufficient lubrication in the eye (p = 0.038), and experience more letter-floating illusions (1.92) than did paper book readers (1.49) (p = 0.043). Moreover, compared to the other formats including the E-book (20%) and paper book (8%), LCD readers (72%) experienced more significant glare symptoms (n = 23) and could read at a faster rate than the other groups of readers (n = 26). CONCLUSIONS: In the present study, the I-Pad caused ocular fatigability more easily than the other formats examined. No statistical significance of ocular discomfort or fatigability was observed among the different format groups. Further investigation with a greater number of age-controlled participants should be conducted prior to designing a study to determine the best format for reading.
Dry Eye Syndromes ; Eye ; Glare ; Illusions ; Lubrication ; Multimedia ; Surveys and Questionnaires

OBJECTIVE: To evaluate female sexual function after colpoperineoplasty. METHODS: Women who visited regional clinic for colpoperineoplasty from June. 2004-Aug. 2004. filled in FSFI (The Female Sexual Function Index) questionnarie before and 4 months after surgery. Six weeks after surgery, they start pelvic muscle training with HMT 2000 (Korea, electric stimulator). RESULTS: Frequency of coitus, sexual desire, arousal, lubrication and orgasm was increased after colpoperineoplasty. Percentage of patients who had coitus more than once a week increased from 18% to 63%. In sexual desire, about 18% felt sexual arousal more than or about half the time before surgery, but increased to 45% after surgery. In sexual arousal, percentage of who felt sexually aroused during more than half of sexual activity increased from 34% before surgery to 69% after surgery. In Lubrication, percentage of who became lubricated during more than half of sexual activity increased from 44% before surgery to 82% after surgery. Who reached orgasm more than half of sexual activity increased from 29% before surgery to 70%. CONCLUSION: Colpoperineoplasty increased female sexual activity.
Arousal ; Coitus ; Female* ; Humans ; Lubrication ; Orgasm ; Sexual Behavior

Carbon fiber reinforced poly ether ether ketone (CF/PEEK) composite possesses excellent biocompatible, biomechanical and bioribological properties. It is one of the most promising implant materials for artificial joint. Many factors influence the bioribological properties of CF/PEEK composites. In this paper, the authors reviewed on the biotribology research progress of CF/PEEK composites. The influences of various factors such as lubricant, reinforcement surface modification, functional particles, friction counterpart and friction motion modes on the bio-tribological properties of CF/PEEK composites are discussed. Based on the recent research, the authors suggest that the further research should be focused on the synergistic effect of multiple factors on the wear and lubrication mechanism of CF/PEEK.
Biocompatible Materials ; Carbon ; Friction ; Ketones ; Lubrication ; Materials Testing ; Polyethylene Glycols

PURPOSE: A new surface structure with a regular patterning of the frictional surfaces of the artificial joints were designed to improve the wear problems. MATERIALS AND METHODS: The lubrication properties for the cup (ultra high molecular weight polyethylene, UHMWPE) vs. ball (Co-Cr alloy) were examined to evaluate the coefficient of friction, wear and surface roughness. The surface structure is a dent pattern, which has diameter of 0.3-0.8 mm, a pitch of 1.2 mm. In this study, such surface patterns were applied to artificial hip joints, and the effects of regular patterning on the frictional surface were examined using a pendulum type hip joint simulator. RESULTS: The coefficient of friction between the cup and a patterned ball showed the same value between the cup and the non-patterned ball. However, the amount of wear of the cup, which was in contact with the patterned head, was only 45% that of the cup, which was in contact with the non-patterned head, and the surface roughness of the cup with the non-patterned head was three times greater than that of the cup with a patterned head. CONCLUSION: These results demonstrate that the lubrication properties can be improved by patterning the frictional surface of the artificial joint. Consequently, patterning on the frictional surfaces can exted the life of an artificial joint.
Friction* ; Head ; Hip Joint* ; Hip* ; Joints* ; Lubrication* ; Molecular Weight ; Polyethylene

PURPOSE: To determine the motion distribution of bipolar hip prosthesis, we performed experimental and clinical analyses. MATERIALS AND METHODS: In the experimental studies, component motion was examined according to surface lubrication, cup angle, and acetabular reaming in fresh-frozen cadaveric bone. In the clinical examination, thirty patients with a bipolar hip prosthesis were examined by fluoroscopy. RESULTS: In the experimental condition when both joints were well lubricated, motion occurred mainly at the inner joint. However, slight motion of the outer joint appeared in terminal abduction if the acetabular cup angle was low and joint pressure was applied. When the only the outer joint was lubricated, motion occurred mostly at the outer joint. When both joints were not lubricated, motion occurred at outer joint unless the acetabular reaming was performed. In every situation having acetabular reaming, motion occurred only at the inner joint. Clinically, motion distribution varied between patients. However, we found a predominant contribution was made by the outer joint, in contrast to theoretical prediction, and the persistence of the combined motion of two joints in the majority of the patients studied (67-70 percent). CONCLUSION: We found that the motion was combined in both outer and inner joint in two-thirds of patients, and that outer motion was more predominated.
Acetabulum ; Cadaver ; Fluoroscopy ; Hip Prosthesis* ; Hip* ; Humans ; Joints ; Lubrication