Results of slotted acetabular augmentation in adults with Crowe stage 1 and 2 hip dysplasia.

To determine the survival of slotted acetabular augmentation in adult dysplasia, we reviewed all cases operated on between 2002 and 2020 with clinical and radiological assessment and a 2.63 year minimum of follow-up. Twenty-three patients were included, with 91% of Crowe 1 hip dysplasia. Seven patients underwent THA at a mean 6.0 ± 3.5 years; 15 retained SAA without THA at a mean 9.5 years' follow-up; 1 was lost to follow-up. There was a significant improvement in PMA and HHS scores, with decreased pain. WOMAC and SF12 quality-of-life scores were moderate due to frequent pain. The patients with preoperative osteoarthritis showed little progression at seven years 'follow-up. We concluded SAA is a corrective treatment for residual hip dysplasia. Its goal is to normalize joint loading by increasing the contact area and improving the lever arm of the hip. Its postponed onset of osteoarthritis and reduced pain, thereby allowing to postpone THA.