The primary objective of this project is to investigate, using RSA, acetabular implant migration of the OsseoTi™ G7 acetabular cup in comparison to conventional PPS coated G7 acetabular cup, and compare liner wear of thinnest available E1™ liner, allowing for the largest possible femoral head (36mm-44mm) to E1™ liner holding a 32mm femoral head in the G7 acetabular system with endpoint assessment being performed at the 2 year follow-up.

Inclusion Criteria:

• • Participants with primary hip osteoarthritis set to receive a primary unilateral uncemented total hip arthroplasty.

  • Participants must be 18-75 years of age.
  • Participants must be able to speak and understand Danish (or depending on country where patient is enrolled).
  • Participants must be able to give informed consent and be cognitively intact.
  • Participants must be expected to be able to complete all postoperative controls.
  • Participants must not have severe comorbidities, ASA-score ≤ 3.

Exclusion Criteria:

• Terminal illness.
• Rheumatoid arthritis.
• Previous fracture of the hip.
• Osteonecrosis of the hip.
• Previous infection of the hip.
• Severe bony deformity warranting the use of non-standard implants.
• Metastasis in the periarticular bone or proximal femur.
• Female patients that are pregnant or planning pregnancy during follow-up period
• If bone stock or femoral canal type, assessed on preoperative x-ray, warrants the use of cemented fixation.
• Documented osteoporosis with patient in active medical treatment.
• Comorbidity with altered pain perception (e.g. DM with neuropathy).
• Participants that develop deep infection in the follow-up period are excluded from the project.