Periacetabular Osteotomy Yields Good Midterm Outcomes for Patients with Down Syndrome and Hip Dysplasia

The treatment of hip dysplasia in patients with Down syndrome is challenging. Until the March 7, 2018 issue of JBJS, only short-term results from periacetabular osteotomies (PAOs) for treating hip dysplasia in this population had been reported.  Now, Maranho et al. review the outcomes among 19 patients (26 hips) who underwent PAOs at Boston Children’s Hospital over 20 years, with an average follow up of 13.1 years.

Defining a “failed PAO” as a postoperative Harris Hip Score (HHS) <60 or a recommendation for a total hip arthroplasty or arthrodesis, the authors demonstrated the following key findings:

• There were significant improvements in all radiographic parameters after the PAOs were performed.
• More than 60% of the patients at their last follow up retained a good or excellent outcome from the procedure (HHS >80).
• The authors found a 36% increase in the odds of failure for every one-year increase in patient age at the time of the PAO and a 17-fold increase in the odds of failure when a patient had Tonnis grade-2 arthritis at the time of PAO, compared to patients with Tonnis grades 0 or 1.

These findings seem to indicate that younger, less arthritic patients with Down syndrome can expect to have reliable outcomes following a PAO. This is encouraging, as it may help those patients maintain independent living by decreasing their arthritis progression and increasing the stability of their hips.  Even though the factors most associated with PAO failure are beyond the surgeon’s control, this data should  facilitate focused discussions among surgeons, patients, and their parents or guardians about expected outcomes in these situations.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media