RESUMO
Objective:To evaluate the efficacy and safety of non-osteotomy total hip arthroplasty (THA) in the treatment of Crowe IV developmental dysplasia of the hip (DDH).Methods:From Jan 2013 to Sep 2021, 46 patients (46 hips) in our department who underwent total hip arthroplasty without osteotomy for unilateral Crowe IV DDH were retrospectively analyzed, including 6 males and 40 females, with an average age of 41.2±7.2 years (25-61 years). The reduction of the femoral head was achieved successfully through moderate upward-posterior displacement of the movement center, gradual osteotomy of the calcar femorale, proper sinking of the femoral prosthesis and sufficient soft tissue release. The evaluation indexes included the basic condition of the operation (operation time, blood loss, blood transfusion, volume), clinical evaluation (Harris score of hip joint function, patient satisfaction, Trendelenburg sign), imaging evaluation (measurement of limb length and pelvic inclination) and incidence of complications.Results:The mean follow-up time was 72.2±8.8 months (8-101 months). The operation time was 97.2±12 min (84-112 min). The average intraoperative bleeding volume was 550±60 ml (350-850 ml). No patient had periprosthetic infection or fracture, no periprosthetic osteolysis or prosthesis loosening, and no patient needed revision surgery at the last follow-up of all cases. The average HHS score of patients increased from 42.5±12.3 points before surgery to 89.2±10.8 points at the last follow-up, and the difference was statistically significant ( t=19.35, P<0.001). Patient self-rated satisfaction: none was very dissatisfied, 1 patient were less satisfied (2%, 1/46), 4 patients were average (9%, 4/46), 19 patients were relatively satisfied (41%, 19/46), and 22 patients were very satisfied (48%, 22/46). The Trendelenburg sign of 46 cases was positive before operation, and all were negative at the last follow-up. The patients' true leg length discrepancy (LLD) measurement was -2.5±0.6 mm before surgery and 11.5±3.2 mm at the last follow-up ( t=29.17, P<0.05). Patients' perceived LLD was 28.2±5.1 mm before surgery and 3.4±1.4 mm at the last follow-up ( t=32.18, P<0.05). The length of the residual calcar femorale was 3.2±0.4 mm after THA. The limb extended distance of affected limb was 45.2±4.6 mm. The preoperative iliolumbar angle was -6.5°±2.3°, which returned to -0.5°±1.3° at the last follow-up ( F=651.97, P<0.05). Conclusion:For patients with unilateral type IV DDH, non-osteotomy THA is a safe and effective surgical method with simple operation and few complications. It can quickly correct pelvic tilt and lumbar compensatory scoliosis postoperatively.