The study evaluated the use of artificial intelligence (AI)-assisted 3D preoperative planning in total hip arthroplasty (THA) in patients with secondary coxarthrosis. It compared the perioperative burden and early recovery in patients with dysplasia of the hip (DDH) and in patients with post-septic sequelae. A single planning route with AI and one type of cementless implant was used. Intraoperative blood loss was found to be lower in patients with DDH, while operative time was comparable. Patients with DDH showed better pain and function 1 month after surgery. After 24 months, the results of patients in both groups were comparable. Postseptic sequelae were associated with greater blood loss and worse pain and function in the early postoperative period.