Randomized controlled trial using two types of hip stems, SL PLUS MIA (control group) and SL PLUS (study group).

We compare primary and secondary stability of both hip stems for radiographic outcome using EBRA (Ein-Bild-Roentgen-Analyse) after a two year follow-up period.

Further, we compare all differences in clinical outcome using Harris Hip Score, Oxford hip score and radiographic findings.

This study is a monocentric study, randomized and controlled including two types of hip stems: SL PLUS MIA (control group) and SL PLUS (study group).

Each group will include 45 patients where a number of 5 patients for each group calculated extra in case of loss.

Patients will be followed after

• 6 weeks
• 6 months
• 12 months
• 24 months. Radiographs are taken in a-p and lateral view using a standard protocol. Primary and secondary stability of both hip stems will be analyzed using the EBRA software (Ein-Bild-Roentgen-Analyse, University of Innsbruck, Austria) after the completion of the two year follow-up.

Further, we compare all differences in clinical outcome using Harris Hip Score, Oxford hip score and radiographic findings such as radiolucent lines.

Inclusion Criteria:

• Patient needs primary total hip arthroplasty with SL-PLUS (standard or lateralized depending on bone morphology)
• Age at surgery : 18-80 years old
• Patient has social security number
• Patient gives Informed Consent (IC) by signing the IC form and patient is willing to attend the follow-up control

Exclusion Criteria:

• Patient's BMI is over 35
• Patient has bone tumors that can affect implant stability
• Patient needs cortical steroid treatment
• Patient needs hip revision arthroplasty
• Patient has general inflammation that could affect bone quality
• Patients classified Charnley C