A modified S-ROM stem in primary total hip arthroplasty for developmental dysplasia of the hip.

This study examined the clinical outcome of 220 hips in 196 Asian patients who underwent primary total hip arthroplasty (THA) for treatment of developmental dysplasia of the hip (DDH) using a modified S-ROM modular (S-ROM-A) stem designed for Asians, after 2-5 years (mean, 3.3 years) of follow-up. The stem was placed so that the anteversion angle of the neck was decreased against the sleeve in 56% of the hips and increased in 18% of the hips. Bone ingrown fixation was achieved in 99.5% of the hips on X-ray at final follow-up. There were 2 (0.9%) dislocations postoperatively. In primary THA for treatment of DDH accompanied by femoral rotational deformity, the freely-rotatable modular stem provided favorable short-term outcomes by affording both morphological and functional advantages.