Study Comparing BoneMaster Hydroxyapatite Coating With Plasma-sprayed Hydroxyapatite Coating on Acetabular Cups

The randomised controlled trial will be carried out on patients that require a total hip replacement (THR) to reduce pain and restore their function. One way of fixing the hip joint to the bone is by coating the implant to encourage the body to grow bone onto the replacement hip. This study is aiming to find out whether the new (Bonemaster) coating allows increased bony growth onto the cup when compared to the usual (plasma-sprayed) coating. This may reduce the incidence of early failures due to poor bony attachment, which is a well known complication for early failure of total hip replacements. The study will compare two different types of coating (BoneMaster and Plasma-sprayed) on the cup of the replacement hip. Density of the bone immediately surrounding the cup will be observed to see if there are differences between the two groups. The density of bone will be measured using standard x-ray assessment and in a smaller sample of 14 patients, using a special scan called Dual Energy X-ray Absorptiometry (DEXA Scan). Functional comparisons will be assessed through clinical scores.