No description available.

The Oxford Unicompartmental Knee Replacement (UKR) is a commonly performed procedure, with a good clinical outcome at 15 years, however, radiolucent lines are commonly found beneath the tibial tray. With the projected increase in knee arthroplasty, particularly in younger patients, implant longevity is of paramount importance. The aim of this thesis is to understand how fixation is achieved with the Oxford UKR and how it can be improved. A histological study demonstrated that in the presence of a radiolucent line the tibial bone-cement interface is made up of a combination of direct bony contact, fibrocartilage and fibrous tissue. The radiolucency is more marked when there is more soft tissue. However in all cases there is some direct bony contact. Cemented and cementless fixation was compared in a randomised controlled study using radiostereometric analysis and fluoroscopic imaging of the interfaces. In the first year the cementless tibial component subsided on average 0.28 mm and had an increased posterior slope of 0.40°, whereas the cemented component only subsided 0.09 mm, with a 0.10° increase in slope. In the second year both components had very little further subsidence (mean<0.05 mm) and no increase in posterior slope. In the second year a single cementless tibial component subsided greater than 0.15 mm, whereas four cemented components, all with radiolucencies, subsided more than 0.15 mm. At two years the cemented components had a significantly higher prevalence of radiolucency (62% v 29%), with 24% having a complete radiolucency, whereas no cementless components had a complete radiolucency. Two designs of lateral UKR were also compared. These had a flat tibial component that predominantly transmits compressive loading, and a domed component that also transmits shear. There was a lower prevalence of radiolucency in the domed tibia (13% v 60%), even though there was a similar amount of migration as the cemented medial tibial component. In conclusion radiolucent lines, both partial and complete, are common with cemented components, and may, in part, be a result of compressive loading. They are associated with good long-term results and direct bone cement contact indicating satisfactory fixation. However, they are also associated with increased migration and soft tissue at the interface suggesting that the fixation, although satisfactory, is suboptimal. The cementless components had no complete radiolucencies and low levels of migration in the second year. This suggests that bone ingrowth and secure fixation occurs reliably, and therefore that cementless fixation may be better than cemented for the Oxford UKR.

No description available.

Class of 2007 Abstract / Objectives: To assess the level of women’s satisfaction with pharmacist intervention, consultation, and services provided in HRT in order to analyze, and improve patient care at Don’s Compounding Pharmacy, Reno, NV. Methods: This descriptive study was done by offering to complete the 14-th questions survey to 300 female patients who had completed their HRT consultation at Don’s Compounding pharmacy. The data collection was performed from September, 19 2006 till January, 15 2007. The returned surveys were then organized and analyzed using Microsoft Excel. Results: Of the 300 surveys offered to complete, 40 were filled out (a response rate of 13.3%). 90% of the participants were customers of the pharmacy up to 5 years. 65% of the participants have used HRT for up to 5 years. The Biest in combination with progesterone or alone was the most prescribed medication (27.5% and 20% respectively). The most often prescribed dosage form was the cream (47.5%). 57.5% of participants answered that a pharmacist has spent 0-5 minutes in average per consultation. All sources of information (pharmacist, physician, mass media, and family/friends) were helpful or very helpful; a pharmacist had the first place among all of them. However, the difference in helpfulness was not statistically significant (benefits and adverse event: P=0.26 and 0.42 respectively). The total satisfaction score with pharmacist’s intervention, education and services was 3.4 (agree, very agree). Conclusions: The majority of the patients from this local pharmacy were satisfied with services provided, and the education received. Despite this fact, time to spend with patients and the education regarding adverse drug events should be improved. The overall patient satisfaction was above the average. Future studies may be considered in studying improvement of the pharmacist’s services and interventions.

Class of 2006 Abstract / Objectives: To determine the effect of compounded bio-identical hormone replacement therapy (BHRT) on menopause-related quality of life through comparing the results of the Menopause Rating Scale (MRS) before beginning BHRT and seven weeks into BHRT. Methods: This study used a one group pre-test/post-test design, also known as pre-experimental. Twenty-one patients participating in a BHRT consultation with the pharmacist at Reed’s Compounding Pharmacy completed an MRS at the time of consultation before beginning BHRT. Seven weeks into treatment with BHRT, patients were mailed a second MRS that they were asked to complete and return to the pharmacy. Results: The average age of the 21 study participants was 54.9±6.3 years. There was a statistically significant reduction in symptom severity for the total MRS and each of the three subscales after seven weeks of treatment with compounded BHRT (p<0.001). Additionally, there were statistically significant reductions in symptom severity related to hot flushes and sweating, sleep problems, depressive mood, irritability, and anxiety (p<0.001). Conclusions: Compounded BHRT is effective in improving menopause-related quality of life in women suffering from menopausal symptoms.

Hydroxyapatite (HA) is a highly biocompatible calcium phosphate which closely resembles the mineral component of bone. Porous structures composed of biocompatible materials are believed to enhance fixation (and integration) as they encourage the ingrowth of bone into the implant. Consequently there is great interest in the potential of porous HA as an alternative to bone homo grafts and auto grafts. However, despite the interest in the field, there has been no thorough investigation into the physical and structural properties of porous HA and their effects on bone ingrowth. The material used in this study was a carbonated apatite (containing < 0.9 % levels of trace element impurities) with a trabecular macrostructure, that had been converted from bovine cancellous bone. The apparent density of the material ranged from 0.35 -1.45 g.cm-3 and the macrostructural morphology varied from an open equiaxed foam to a columnar honeycomb-like structure. The ultimate compressive stress was strongly related (r = 0.9) to the square of the apparent density, while compressive modulus was influenced by both apparent density and macrostructural morphology. Transmission electron microscopy of human osteoblast-like cells cultured on the material demonstrated that cells were closely associated with the surface. Specimens with densities of 0.6.0.9 and 1.2 g.cm-3 were then implanted in a lapine cancellous site for periods of 10 days, 3, 5, 13 and 26 weeks. After implantation all specimens elicited a highly biocompatible response, with active areas of bone deposition, remodelling and revascularization and no fibrous encapsulation. The amount of bone ingrowth within the implant (25-10%) after.5 weeks was found to vary with apparent density (0.6-1.2 g.cm-3) indicating that osseointegration was a function of macrostructural morphology. Pushout testing of retrieved spedmens indicated that all implants were securely fixed by 5 weeks (2-3 MPa). Compression testing demonstrated that after 5 weeks low density implants were sufficiently reinforced by bone ingrowth to equal the compressive strength of the host tissue (6 MPa) which increased to approximately 20 MPa at 3 and 6 months.

Total hip replacement (THR) is one of the most successful and most frequently performed operations. For most implants the published rate of revision at 10 years is less than 10%. However the revision rates are higher for younger and more active patients who are likely to outlive their implants. The most frequent cause of THR failure is aseptic loosening, commonly accompanied by bone loss at the implant site. THR revisions give worse functional results and fail sooner than primary THR and are complicated by this loss of bone stock. A resurfacing hip prosthesis replaces the diseased surface layer of bone and cartilage and retains the majority of the femoral head. The stress distribution in the proximal femur is closer to that in an intact hip. A conservative resurfacing prosthesis will present the surgeon with no greater problems at revision than encountered at primary conventional 11-JR. Early designs of resurfacing prosthesis conserved femoral bone stock at the expense of acetabular bone. Revision rates were high and while some failures were caused by avascular necrosis and femoral neck fracture the predominant cause was acetabular loosening. The design of a bone conserving prosthesis requires knowledge of the shape of the bony surfaces of the hip joint. A survey of the morphology of the acetabulum showed a wide variation in shape. While early resurfacing designs had hemispherical acetabular cups the bony surface is less than hemispherical. The morphology and desired range of hip motion constrain prosthesis thickness and shape. A novel resurfacing design using a polyacetal femoral component and an UHMWPE acetabular component is proposed. This bearing combination has a lower volumetric wear rate than an equivalent Co-Cr on UHWMPE bearing. Computer modelling of the resurfacing concept showed that lower moduli materials reduced stress shielding and distributed implant-bone interface stresses more evenly. Mechanical testing of polyacetal following immersion in Ringer's solution showed substantial decreases in Young's modulus while strength was unaffected.

No description available.

This research addresses the large-scale group fleet replacement problem with multiple vehicle types of multiple units, under budget and demand constraints. Past research in group fleet replacement is limited and has focused on one vehicle type, with multiples units and constraints. Many studies in fleet replacement have also dealt with single replacement, with single units, and with no constraints. The objective of this research is to find the methodology to solve the general large-scale group fleet replacement problem. A multi-phase methodology based on the grouping concept is presented and is integrated with optimization techniques. The vehicles are grouped according to various technology parameters. A two-level hierarchical replacement process, focusing on inter-group, and intra-group analysis, is developed and the resulting models are solved using integer programming. Finally, a case study using the Oregon Department of Transportation records is examined. The replacement model presented can incorporate complex variations in the large-scale group fleet replacement problem. It is flexible and can be used in wide variety of replacement problems. Used appropriately, the results from this methodology can result in reduced fleet replacement costs and operation costs. / Graduation date: 2001

Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Lynn Snyder-Mackler, Dept. of Physical Therapy. Includes bibliographical references.