Hip-specific quality of life survey for patients with hip osteoarthritis - development and preliminary validity assessment.

BACKGROUND: Many various surveys are used to assess quality of life of patients with hip osteoarthritis, but none of them evaluates quality of life dependent on a single joint in bilateral disease. Aim. Development and preliminary validation of hip-specific quality of life survey (HSS) of patients with hip osteoarthritis. MATERIAL AND METHODS: A group of experts developed the final version of HSS questionnaire in 4 stages. Statistical analysis was conducted on 181 preoperative and postoperative HSS questionnaires completed by patients undergoing hip replacement surgery due to hip osteoarthritis. Discrimination index for each item, questionnaire internal consistency, proportion and dispersion of unanswered items, questionnaire filling time, ceiling effect and floor effect values as well as correlation between each item and subscale score were subject to statistical analysis. RESULTS: Final version of the questionnaire is characterized by good discriminant power (CR >3 for each item except for one). Cronbach alpha coefficient for each subscale of preoperative as well as postoperative questionnaire reached a value over 0.8 and point value for each item correlated significantly with the sum of points in each HSS subscale. CONCLUSIONS: No floor effect was observed in any of the cases, while ceiling effect was demonstrated in 1.1% of preoperative HSS questionnaires.

Patient-related outcome questionnaires in the assessment of the results of total hip replacement.

A variety of patient-related outcome questionnaires have been used for the assessment of results of total hip replacement. Generic core scales (SF-12, SF-36) and disease-specific scales like: Harris Hip Score, Western Ontario and McMaster University Osteoarthritis Index, Hip dysfunction and Osteoarthritis Outcome Score, Oxford Hip Score, American Academy of Orthopedic Surgeons hip and knee Questionnaire, Lower Extremity Functional Scale are used most frequently. Even though all of them were assessed in terms of construct and content validity, reproducibility and sensitivity, there are still some problems related to bias when total hip replacement evaluation is performed in the presence of comorbidities, contralateral hip disease and ceiling effect influencing the final score. As a result, there is a need for development of a new PRO questionnaire in order to improve total hip replacement assessment, enable early detection of postoperative complications or to evaluate the results of surgery in both hips separately. It is crucial that such measuring device has to be deprived of the influence of irrelevant factors on the final score.

[Evaluation of outcomes following total hip arthroplasty]. / Ocena odleglych wyników endoprotezoplastyki stawu biodrowego proteza bezcementowa typu Zweymüller.

BACKGROUND: Osteoarthritis of the hip, one of the most frequent civilization diseases, causes not only a large physical and psychological stress for the patients but also generates increasing costs of treatment each year. The aim of our study was to evaluate the patients' functioning in the period of 3-12 years after the Zweymüller total hip arthroplasty. MATERIAL AND METHODS: 323 patients, aged 27-83 years, after the primary Zweymüller cementless total hip arthroplasty, operated in the Orthopedics and Traumatology Department of Poznan University of Medical Sciences. The evaluation was based on the Western Ontario and McMaster Universities (WOMAC) questionnaire supported with additional questions concerning the weight, height, dwelling place, education level, occupational activity, additional diseases and other joints problems. RESULTS: The Zweymüller cementless total hip arthroplasty is characterized by a good stability in 97.8% of patients during the 3-12 years of postoperational period. Additional problems associated with any unoperated lower limb joint almost always result in the increase of the WOMAC score. A positive correlation was also noticed between the level of education and the occupational activity after the treatment in patients with similar WOMAC score. No influence of overweight on the postoperative activity occured. Moreover our study revealed a negative correlation between BMI (Body Mass Index--range up to 40) and the WOMAC form. CONCLUSIONS: The functional evaluation of patients after total hip arthroplasty should consider information about other lower limbs joints problems for better objectivity. It should be mentioned that the occupational activity correlates positively with the level of patients education. The obesity cannot be the criteria disqualifying from the operation as it does not influence the activity after the hip replacement.

Equilibrium study of selected divalent d-electron metals adsorption on A-type zeolite.

The objective of the presented study was to investigate the adsorption of Cu, Co, Mn, Zn, Cd and Mn on A-type zeolite. The isotherms for adsorption of metals from their nitrates were registered. The following adsorption constants K of metals were found: 162,890, 124,260, 69,025, 16,035, 10,254, and 151 [M(-1)] for Cu, Co, Mn, Zn, Cd, and Ni, respectively, for the concentration range 10(-4)-10(-3) M. On the other hand, the investigation of pH influence on the distribution constants of metals showed that the adsorption of metals proceeds essentially through an ion-exchange process, surface hydrolysis, and surface complexation. The supplementary results from DRIFT, scanning electron microscopy, and X-ray diffraction methods confirmed the presumption about the possible connection between the electronic structure of divalent ions and their adsorption behavior, showing that ions with d5 and d10 configurations such as Mn2+, Zn2+, Cd2+, with much weaker hydrolytic properties than Cu2+ and Ni2+, strongly interact with the zeolite framework and therefore their affinity to the zeolite phase is much stronger when compared with that of the Ni2+ ion, but at the same time not as strong as the affinity of the Cu2+ ion, the latter forming a new phase during the interaction with zeolite framework. For Zn2+, during inspection of the correlation between the proton concentration H/Al and zinc concentration Zn/Al on the zeolite surface, the formation of the surface complex [triple bond]S-OZn(OH) was proposed. A correlation between the heterogeneity of proton concentrations H/Al on Me-zeolite surfaces and the hydrolysis constants pKh of Me2+ ions was found.