None listed
Conditions
Brief summary
This clinical study is a prospective, randomised, multi-centre study that will enrol 144 patients over a 12-month recruitment period between three surgeons and three centres. The objective of the study is to investigate if the Mathys RM Pressfit Cementless Cup maintains acetabular bone stock by reducing the effects of stress shielding when compared with a conventional rigid cementless acetabular cup. This study also aims to demonstrate safety, and equivalent clinical outcomes to standard care. The RM Pressfit Cementless cup is designed to have a modulus of elasticity that is similar to bone, and therefore it may be possible to transfer physiological loads through the cup and prevent the bone behind the cup from resorbing due to stress shielding. The control group for this study will be a standard hip replacement with a conventional rigid cementless acetabular cup. Standard, functional parameters will be assessed pre-operatively, and post-operatively at 6 weeks, 6 months, 12 months, 2 years and 5 years. Antero-posterior and lateral radiographs will be analysed at 6 weeks, 1 year and 5 years to assess femoral stem and acetabular cup orientation. DEXA (measures bone density) scans will be assessed pre-operatively at 6 weeks, 6 months, 12 months, 2 years and 5 years to measure acetabular bone density, with the aim of showing preservation of bone behind the RM Pressfit Cup when compared to a conventional rigid cup.
Interventions
RM Pressfit Acetabular Cup. The cup is a cementless monoblock press-fit acetabular cup and it is manufactured from UHMWPE, which is stabilised with Vitamin E. The outer surface of the polyethylene is coated with titanium particles for bony in-growth.
This device has no metal shell, and is designed to be flexible in the acetabular bone, unlike a conventional uncemented acetabular cup.
A standard total hip replacement will be performed to implant the device, according to the individual surgeons
RM Pressfit Acetabular Cup. The cup is a cementless monoblock press-fit acetabular cup and it is manufactured from UHMWPE, which is stabilised with Vitamin E. The outer surface of the polyethylene is coated with titanium particles for bony in-growth. This device has no metal shell, and is designed to be flexible in the acetabular bone, unlike a conventional uncemented acetabular cup. A standard total hip replacement will be performed to implant the device, according to the individual surgeons normal practice.
Sponsors
Mathys Orthopaedics Pty Ltd
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
1. Patients with symptomatic arthritis who are candidates for a primary total hip replacement with an uncemented or cemented femoral stem as determined jointly by the surgeon and the patient. 2. Patients suitable for an uncemented acetabular component 3. Patients who understand the conditions of the study and are willing to participate for the length of the prescribed follow-up
Exclusion criteria
1. Patients who have had previous contralateral hip replacement surgery 2. Pregnant women or those seeking to become pregnant 3. Patients with a history of active infection 4. Patients with conditions or medications associated with osteoporosis or osteopenia ie: bisphosphonates, Protos, steroids and previous acetabular surgery on the affected side. 5. Patients who have severe arthritis of contralateral hip
Outcome results
None listed