Fixatie en migratie van het G7 BiSpherical acetabulair systeem gecombineerd met de GTS steel voor totale heupvervanging- een RSA studie.

Rationale: Cementless total hip arthroplasty (THA) has very good clinical results. As a result of the success, the ageing population and because the procedure is performed in increasingly younger and more active patients, the number of THA procedures has increased the last decades. After failure of a primary THA, a more challenging and costly hip revision surgery is needed, mainly due to management of the bone stock loss. Therefore, the new shorter GTS stem was developed to prevent the loss of bone stock.

Nowadays the risk of poor performing survival over time should be limited. The only clinical test that can provide data to predict long survival is stability testing with RSA. As a result, the risk of implanting potentially inferior prostheses in patients will be reduced, resulting in less suffering for patients and a reduction in healthcare expenses.

This study identifies the radiographic outcomes, implant survival, fixation and migration patterns of the G7 BiSpherical acetabular system combined with the GTS stem, up to five years after implantation.



Objective: Identifying the fixation and migration patterns of the G7 BiSpherical acetabular system combined with the GTS stem (Zimmer Biomet) prosthesis in vivo, using model based roentgen radiostereophotogrammetric (mRSA) analysis over a period of 5 years.



Study design: A prospective clinical trial in which 25 cases will be enrolled over one hospital. Patients will be evaluated preoperatively and postoperatively at discharge (from operation date to date of discharge), at 6 weeks, 6 months, 1 year, 2 years and 5 years.



Study population: The study population consists of active male or non-pregnant female 18-75 years of age. The subjects have no clinical relevant disorders of the hip and they will undergo a hip arthroplasty with the G7 BiSpherical acetabular system combined with the GTS stem, after diagnosis of osteoarthritis.



Intervention (if applicable): Placement of the G7 BiSpherical acetabular system combined with the GTS stem.



Main study parameters/endpoints: Outcome will be clinically measured using the HOOS-PS, EQ5-D and OHS whilst radiographic outcomes will be evaluated through standard radiographic parameters. RSA will be used to measure migration of the prosthesis.



Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Subjects participating in the study have the same risks and benefits when not participating in the study. All components used in the study have CE mark and are already in use. Besides standard radiological follow-up, RSA x-rays will be made to measure the fixation of the prosthesis.

 

The G7 BiSpherical acetabular system and the GTS femoral stem will have acceptable migration patterns at the two-year follow-up mark (G7 BiSpherical acetabular system) and at six months (GTS femoral stem)

• Pre-operative

• 6 weeks

• 6 months

• 1 year

• 2 years

• 5 years

Placement of the G7 BiSpherical acetabular system and the Global Tissue Sparing (GTS) femoral stem, with insertion of tantalum beads for radiostereophotogrammetric analysis(RSA)