A prospective randomized study comparing accuracy and precision of acetabular component placement in total hip arthroplasty with use of novel electromagnetic navigation system versus freehand technique.

Patients with hip arthritis, who are to be treated with total hip arthroplasty will be randomized in two groups. Patents allocated to study group will get their acetabular components implanted with the help of electromagnetic navigation system. Patients allocated to the control group will get their acetabular components implanted with freehand technique. Accuracy and precision of implanted acetabular components will be assessed on images obtained by postoperative computed tomography. Postoperative inclination and anteversion angles of acetabular components will be measured by the independent technician. Results will be statistically analyzed and compared.

Inclusion Criteria:

• age above 18 years
• unilateral surgery
• osteoarthritis of the hip
• no previous surgery on the affected hip
• implantation of the same acetabular component through the same approach
• signed informed consent

Exclusion Criteria:

• age under 18 years
• unwilling to participate
• prior surgery on affected hip

No data will be shared with other researchers.

Postoperative computed tomography measurements of acetabular component position will be done by independent technician.