Fig. 2.

Four groups were defined using BMI, bariatric surgery, implants (standard, dual mobility, constrained cups) as criteria of selection. Group 1 consisted of 215 THAs in patients with obesity (BMI > 30 kg/m²) receiving standard implants. Group 2 consisted of 215 THAs in patients defined as nonobese (BMI < 30 kg/m² on the day of surgery) and receiving standard implants. Group 3 consisted of 85 THAs in patients with obesity having bariatric surgery before THA (with reduction of BMI < 30 kg/m² on the day of surgery) and receiving standard implants. Group 4 consisted of patients with obesity who received dual-mobility (85 THAs) or constrained liners (70 implants).