Abstract:[Objective] To evaluate the clinical efficacy of unfixed acetabular double column combined with posterior wall fracture under the iliac-groin approach. [Method] From May 2016 to January 2021, the clinical data of 30 patients with acetabular double-column combined posterior wall fracture treated under the iliac-groin approach; 17 males and 13 females; age 22-76 years old, average (41.4±15.5) years old; Judet-Letournel acetabular classification is all acetabular double-column combined with posterior wall fractures. The operation is performed under general anesthesia using an iliac-groin approach, and the iliac wing fractures are fixed with steel plates or lag screws. The column was fixed with a steel plate, the posterior column was fixed with a posterior lag screw, and the posterior wall was not fixed. During follow-up, the hip joint function was evaluated using Matta''s modified Merle d''Aubigne-Postel scoring system, and the Matta method was used to evaluate the reduction of acetabular fractures; The patient''s operation time, blood loss, fracture displacement, infection, etc. [Results] The follow-up time was 8-58 months. All 30 patients were followed up with an average of (25.5±10.6) months; operation time: 90-300min, average (140.5±30.3) min; intraoperative bleeding 500-3000ml, average (805.4±500.7) ml; no case of posterior wall fracture occurred re-displacement during the postoperative follow-up. The quality of fracture reduction evaluated by Matta method: excellent in 10 cases, good in 16 cases, poor in 4 cases, the excellent and good rate was 86.7% (26/30); at the last follow-up, Merle d''Aubigne-Postel score was 13-18 points, average (16.8±1.2) 9 cases were excellent, 18 cases were good, 3 cases were fair, and the excellent and good rate was 90.0% (27/30); 8 cases had lateral femoral cutaneous nerve symptoms after surgery, and 2 cases had not disappeared at the last follow-up; 1 case had symptoms The incision was fat liquefied and healed after debridement and dressing change. 2 cases developed deep venous thrombosis of the lower extremities and were treated with rivaroxaban anticoagulant therapy; none of the cases developed heterotopic ossification, sciatic nerve injury, and reoperation. [Conclusion] In the type of acetabular double-column combined with posterior wall fracture, the posterior wall bone block can also achieve good clinical results without fixation.