Does short stem THA Improve Accuracy of Femoral Stem Positioning in the Axial Plane: a Randomized Clinical Trial, Comparing Two Implant Philosophies

Not Applicable

Recruiting

Conditions: M16
M06
M87
S72
M19.1
Coxarthrosis [arthrosis of hip]
Other rheumatoid arthritis
Osteonecrosis
Fracture of femur
Post-traumatic arthrosis of other joints

Registration Number: DRKS00026181

Lead Sponsor: Charite Berlin, Centrum für Muskuloskeletale Chirurgie

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Recruiting

Sex: All

Target Recruitment: 40

Inclusion Criteria

Patients may be included in the study only if they meet the following criteria:
• Patient is eligible to A2 (ARTIQO GmbH) and SL-Plus MIA (Smith & Nephew Orthopaedics AG) total hip arthroplasty
• Patient is able to provide informed consent
• Patient is willing to attend all follow-up visits and complete all study requirements
• Patient is willing to adhere to the rehabilitation protocol
• Patient has one of the following indications:
o Primary osteoarthritis of the hip
o Avascular necrosis, posttraumatic osteoarthritis, rheumatoid arthritis
o Displaced femoral neck fracture
• Patient has sufficient bone quality for total hip arthroplasty.
Note: patients can only enter the project with one hip.

Exclusion Criteria

• Acute or chronic infections, local or systemic
• Severe muscular, nervous or vascular diseases impairing the affected limb
• Missing bone substance or poor bone quality, which jeopardizes stable fit of the prosthesis
• Previous operations that no longer guarantee stability of the prosthesis
• Pronounced coxa valga with a femoral neck angle> 145°
• Pronounced coxa vara with a femoral neck angle <120°
• Any concomitant disease that may jeopardizes functioning of the implant
• Arthroplasty revision procedures.

Study & Design

Study Type: interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
The aim of the study is to compare the ability of two stem types to restore of native anatomy. The current study will take stem anteversion (axial plane alignment) as measured by Magnetic Resonance Imaging after a standing time of 6 months as primary endpoint.

Secondary Outcome Measures

Name	Time	Method
• Stem tilting in the sagittal plane (6 month follow-up)<br>• Anterior offset (6 month follow-up)<br>• Lower limb alignment as measured by long-standing radiography (6 month follow-up)<br>• Postoperative functional outcome as measured by the Harris Hip Score and the University of California at Los Angeles (UCLA) Score (6 weeks follow-up and 6 month follow-up)<br>• Serum myoglobin concentration and creatine kinase activity (4 & 24 hours post operative)<br>• Presence of fatty atrophy of the gluteus medius and gluteus minimus on MRI (6 month follow-up)<br>• Presence of tendon tears and detachments on MRI (6 month follow-up)<br>• Presence of bursal fluid collections on MRI (6 month follow-up)<br>• Blood loss, level of hemoglobine (6 weeks follow-up)