Fluid flow characteristics within an oscillating lower spherical surface and a stationary concentric upper surface for application to the artificial hip joint

The synovial fluid motion in an artificial hip joint is important in understanding the thermo-fluids effects that can affect the reliability of the joint, although it is difficult to be studied theoretically, as the modelling involves the viscous fluid interacting with a moving surface. A new analytical solution has been derived for the maximum induced fluid motion within a spherical gap with an oscillating lower surface and a stationary upper surface, assuming one-dimensional incompressible laminar Newtonian flow with constant properties, and using the Navier-Stokes equation. The resulting time-dependent motion is analysed in terms of two dimensionless parameters R and β, which are functions of geometry, fluid properties and the oscillation rate. The model is then applied to the conditions of the synovial fluid enclosed in the artificial hip joint and it is found that the motion may be described by a simpler velocity variation, whereby laying the foundation to thermal studies in the joint.

Zoledronic acid treatment for cancerous bone metastases: a phase IV study in Taiwan

AIM OF STUDY

To investigate the features, adverse effects, bone marker changes in patients with breast cancer, prostate cancer, and multiple myeloma with bone metastases under Zometa® therapy.

MATERIALS AND METHODS

This post-marketing study included 414 Taiwanese patients with bone metastases secondary to breast cancer, prostate cancer, or multiple myeloma who received Zometa® for 48 weeks. The patients' characteristics, medication and adverse events were recorded, meanwhile changes in four serum bone metabolic markers and pain reduction were assessed every three months for one year.

RESULTS

A total of 3,711 doses of Zometa® were infused, accounting for 294.5 patient-years. Adverse events occurred in 9.4% of patients, with bone pain, insomnia, constipation, and pyrexia as the most frequently reported. There was no osteonecrosis of the jaw. The incidence of skeletal-related events decreased significantly from 44.9% to 18.8%. Serum NTx, BAP, and TRACP5b steadily decreased to nadir at six months, but serum OPG was persistently elevated until the end of one year. The average decrease in pain score was 14.1, 14.3, and 16.7 for prostate cancer, breast cancer, and multiple myeloma patients, respectively.

CONCLUSION

Zometa® can be safely administered in Taiwanese patients with bone metastases secondary to breast cancer, prostate cancer, and multiple myeloma. There are concomitant decreases in skeletal-related events and bone pain.