Total hip replacement (THR) in children and very young teenagers is experimental since we do not know long-term results in these. We investigated the clinical and radiographic outcomes of THR performed in children and teenage patients identified in the Norwegian Arthroplasty Register

We included 111 patients (132 hips) who underwent THR before 20 years of age., together with information on the primary diagnosis, types of implants, and any revisions that required implant change. Radiographs and Harris hip score (HHS) were evaluated for patients that attended clinical follow-up.

The mean age at primary THR was 17 (11–19) years, 60% were girls. Mean follow-up time was 14 (3–26) years. The 10-year survival rate after primary THR (with endpoint any revision) was 70%. Survival was better for the patients operated after 1996 (10 y 50% vs 90%). 39 patients had at least 1 revision and 16 patients had 2 or more revisions. In the latest radiographs, osteolysis and atrophy were observed in 19% and 27% of the acetabulae and 21% and 62% of the femurs, respectively. The mean HHS at the final follow-up was 83 (15–100). EQ-5DVAS was 74 (82 in normal population).

The clinical scores after THR in these young patients were acceptable, but many revisions had been performed. The bone stock in many patients was poor, which could complicate future revisions.