[Effectiveness of total hip arthroplasty in patients with a history of hip preservation surgery with secondary osteoarthritis for developmental dysplasia of the hip].

To evaluate early to medium-term effectiveness of total hip arthroplasty (THA) in patients with a history of hip preservation surgery with secondary severe osteoarthritis for developmental dysplasia of the hip (DDH).
The clinical data of 25 DDH patients (31 hips) who had severe osteoarthritis after hip preservation surgery and received THA between September 2009 and March 2021 were retrospectively analyzed. There were 1 male and 24 females; the age ranged from 18 to 65 years, with an average age of 43 years; 8 hips were classified into Crowe type Ⅰ, 9 hips were type Ⅱ, 3 hips were type Ⅲ, and 11 hips were type Ⅳ. The time between osteotomy and THA ranged from 31 to 51 years, with an average of 31.96 years. Preoperative hip flexion range of motion was (69.31±29.72)°, abduction range of motion was (24.00±14.79)°; and Harris hip score was 45.3±15.5. Postoperative Harris hip score, hip range of motion, complications, radiographic findings, and implant survival rate were analyzed.
Patients in both groups were followed up 2-132 months, with an average of 51 months. During the follow-up, periprosthetic fracture occurred in 1 case; there was no complication such as dislocation, periprosthetic infection, nerve palsy, or deep vein thrombosis. At last follow-up, the hip flexion range of motion was (109.52±11.17)°, abduction range of motion was (41.25±5.59)°, showing significant differences when compared with preoperative values ( =8.260, 0.000; =6.524, 0.000). The Harris hip score was 91.5±4.1, and the difference was significant when compared with preoperative score ( =11.696, 0.000); among them, 13 cases were excellent and 12 cases were good. Radiographic evaluation showed that the center of acetabular rotation moved up 0-18 mm (mean, 6.35 mm). The cup abductor angle was 28°-49° (mean, 37.74°) and the coverage rate was 69.44%-98.33% (mean, 81.04%). All femoral stems were fixed in neutral position without varus or valgus. No osteolysis, radiolucent line, or implant migration was observed. By the end of follow-up, none of the patients underwent revision and the survival rate of prothesis was 100%.
THA is still the gold standard for the treatment of DDH patients with secondary osteoarthritis after hip preservation surgery. The postoperative joint function can be rapidly restored, the patients’ quality of life can significantly improve, and the early to medium-term survival rate of the prosthesis is satisfactory.