Application Of Autologous Structural Bone Graft In Treatment Of DDH Acetabular Bone Defect

Purpose:To estimate the value of autogenous bone graft in the treatment of acetabular bone defects in patients with developmental dysplasia of the hip.Methods:We retrospectively analyzed the survival of bone grafts in 18 patients(mean age 48 years)with DDH after cementless total hip arthroplasty.Among them,there were 16 cases(16 hips)with female and 2 cases(2 hips)with male,all of 18 hips are needed autogenous bone graft to improve the acetabular bone defect.The average follow-up time was 3.39 years(2-6 years).According to Crowe et al's classification of hip dysplasia,there were 7 hips with Crowe type ?,8 hips with Crowe type ? and 3 hips with Crowe type ?.The function of hip joint was evaluated by comparing the VAS score,Harris score and the length difference of both lower limbs in preoperation,postoperation and the last follow-up.The stability of acetabular cup and the survival of bone graft were further discussed by the changes of acetabular coverage measured in X-ray.Result:All of the 18 patients had bone integration with the host bone,the acetabular prosthesis where there was no obvious radiolucent shadow around was stable.But 4 patients had osteolysis of the transplanted bone,of which 1 patient had extensive bone absorption on the lateral side of the bone graft.The VAS score was(1.39 ± 0.76),Harris score was(83.19 ± 3.42),and the difference in the length of lower limbs was(12.35 ± 7.46)mm at the last follow-up.The pain symptoms of hip joint were significantly reduced and the function was improved.The horizontal coverage rate of acetabulum(host bone and structural bone graft)decreased from(122.10±11.23)% after operation to(109.74±9.94)% at the last follow-up,but was significantly higher than that of host bone(61.96±6.30)%.CE angle increased from(10.02±5.71)° preoperatively to(56.50±10.66)° postoperatively,but decreased to(52.03±9.97)° at the last follow-up.All the differences were statistically significant.Conclusion:When the patients with developmental dysplasia of the hip are treated with cementless total hip arthroplasty,the grafted bone will appear osteolysis to some extent in the host bone coverage rate of more than 40%,but it can still obtain effective bone integration.Autologous bone graft can effectively improve acetabular bone defects,increase bone reserves,and is conducive to the restoration of hip rotation center and lower limb length.Mid-term follow-up shows that it is reliable to improve acetabular bone defect by structural bone grafting.