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

Not Applicable

Completed

Interventions: Device: BoneMaster coated acetabular shell.
Device: Plasma Coated Acetabular Shell

Brief Summary: 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.

Detailed Description: The patients will be identified by the orthopaedic surgeon in the orthopaedic clinic and deemed suitable for the study if all inclusion and exclusion criteria are met. 210 patients will be recruited to the study and each patient will be randomised into either of the groups allowing 105 patients into each group. Patients will be followed up at 6 months, 1 year and 2 years after the surgery. All patients will have radiographic assessments at these follow-up intervals, as well as Harris Hip, Oxford Hip and Womac scores. This will allow comparison of the two groups.

The BoneMaster coating has been extensively tested in cell and animal studies and has been evaluated in one previous clinical study and showed favorable results. Further investigation is required to ensure the new coating may enhance bony growth allowing better fixation of the hips in the early period after the operation and also over a longer period of time. The growth needs to be measured using a more sensitive scan than radiographic assessment alone, called DEXA which was also used in the previous study.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
BoneMaster coated shell	BoneMaster coated acetabular shell.	Exceed ABT BoneMaster hydroxyapatite coated acetabular cup.
Plasma-sprayed shell	Plasma Coated Acetabular Shell	Exceed ABT plasma-sprayed hydroxyapatite coated acetabular cup.

Primary Outcome Measures

Name	Time	Method
Record and Measure Bone Density Using DEXA Scans at 24 Months.	2 years.	DEXA scan cohort - DEXA scan was used to measure bone density. Below is the calculated net average bone mineral density (BMD) percentage change from baseline at 2 years.
Radiography to Determine Radiolucency in All Three DeLee & Charnley Zones of the Acetabulum.	2 years.	34 patient cases without duplicated data were the basis for the radiographic analysis that was conducted: Bonemaster group, n = 12; Plasma-Sprayed group, n = 22. The degree of osseous-fixation was determined by grading: 1-2 mm radiolucencies, classed as not fixated; \>2mm radiolucencies, classed as unstable.

Secondary Outcome Measures

Name	Time	Method
Secondary Outcomes Are Functional Assessment Using Harris Hip Score	2 years	Modified Harris Hip Score, total score 0-100. A score of \<70 is poor, 70-79 is fair, 80-89 is good, 90-100 is excellent.
Secondary Outcomes Are Clinical Assessment Using Oxford Hip Score	2 years.	Oxford Hip Score, scored 12-60. The Oxford hip score - this score was based on the original publication where each answer gives a score of 1-5. A score of 1 for each question, represented best outcome/least symptoms. Therefore a total score of 12 was the best overall outcome.
Secondary Outcomes Are Clinical Assessment Using WOMAC Hip Score	2 years	Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Hip Score, Each question is scored on a scale of 0 (best health state) to 4 (worst health state); total WOMAC hip score, 0 being the best and 96 being the worst.