Single-stage bilateral conversion arthroplasty for hip fusion via direct anterior approach in a patient with severe ankylosing spondylitis and kyphoscoliosis: a case report.

BACKGROUND: Severe ankylosing spondylitis (AS) frequently involves hip joints and, occasionally, presents with concurrent spinal deformities, such as kyphoscoliosis, creating complex challenges for surgical management.

CASE PRESENTATION: We present a 26-year-old Persian male with a history of AS and severe kyphoscoliosis, leading to bilateral hip fusion and immobility. Following spinal deformity correction, a one-stage bilateral conversion to total hip arthroplasty (THA) was conducted through the direct anterior approach.

CONCLUSION: Primary correction of spinal deformities allows for extended surgical procedures under general anesthesia. Single stage bilateral hip conversion arthroplasty via the direct anterior approach enhances postoperative mobilization, reduce the risk of re-ankylosis, and improve the overall quality of life for AS patients with this unique presentation.