Analysis Of Mid-Term Therapeutic Effects Of Two Different Placement Positions Of Developmental Hip Dysplasia Biotype Acetabulum

Purpose:Exploring the clinical efficacy of two types of placement of biological acetabular implants in total hip arthroplasty(THA)for the treatment of developmental dysplasia of the hip(DDH),as well as the effectiveness and safety of appropriate upward displacement of acetabular implants,in order to provide reference for the placement of acetabular implants in DDH patients.Materials and methods:A retrospective analysis was conducted on 42 patients(47 hips)who underwent THA for DDH at our hospital from January 2014 to October 2020,including 8 males and 34 females.Among them,there were 21 hips of Crowe I type,19 hips of Crowe II type,and 6 hips of Crowe III type;One case of Crowe IV type hip,with a acetabular prosthesis size of 40～56 mm.Before routine surgery,perform pelvic AP,hip AP lateral,and hip CT plain scan with 3D reconstruction,and preliminarily measure the placement position and size of the acetabular prosthesis to achieve a bone coverage rate of over 70%,as well as an appropriate acetabular anteversion angle and abduction angle.Grind the acetabulum at or as close as possible to the true acetabulum during surgery,and move the center of rotation up appropriately according to the specific situation during the surgery,with the center of rotation not exceeding 15 mm.Collect imaging results of pelvic and hip joint anteroposterior and lateral positions after surgery,evaluate the placement position of acetabular implants,measure the distance between the rotation center and the lower edge of the tear drop and the distance between the healthy side anatomical center and the lower edge of the tear drop after surgery,and subtract the two to obtain the upward displacement height.According to the upward displacement height,they are divided into two groups: the rotation center is basically the same as the healthy side anatomical reduction group(<5 mm)and the improved upward displacement group(5～15 mm).The final follow-up evaluation collected survival results,imaging results,and clinical results,including survival rate,vertical and horizontal distance of the hip joint center(acetabular eccentricity),femoral eccentricity,acetabular anteversion angle and abduction angle,difference in length of both lower limbs,Harris score,Western Ontario And Mcmaster Universities Osteoarthritis Index(WOMAC),Trendelenburg sign,and claudication,The amount of intraoperative bleeding was recorded to observe whether there were complications such as blood transfusion,deep vein thrombosis(DVT),pulmonary embolism(PE),nerve injury,infection around the prosthesis,aseptic loosening of the prosthesis,fracture around the prosthesis,dislocation of the acetabular pad,and abrasion.Result:1.All patients were followed up,and there was a statistically significant difference in gender and age between the two groups of data(P<0.05).There was no statistically significant difference in surgical side,follow-up time,and body mass index(BMI)(P>0.05).2.The survival rate of the two groups of patients was 100%,and there was no statistically significant difference in intraoperative blood transfusion and bleeding volume between the two groups(P>0.05).Postoperative incisions in all patients healed in stage I,without complications such as DVT or PE,nerve injury,periprosthetic infection,aseptic loosening of the prosthesis,periprosthetic fractures,dislocation of the acetabular pad,and wear.3.There was a statistically significant difference in the vertical distance between the two groups of hip joint rotation centers(P<0.05);There was no statistically significant difference in horizontal distance(acetabular eccentricity),femoral eccentricity,anteversion angle,and abduction angle between the two groups(P>0.05);The difference in length between the two groups’ lower limbs decreased during the last follow-up,and there was a statistical difference(P<0.05)between the last followup and before surgery;However,there was no statistically significant difference in the length difference between the two groups of lower limbs during preoperative and final follow-up(P>0.05).4.The Harris score and WOMAC score of the two groups of patients at the last follow-up were significantly improved compared to before surgery,and the difference was statistically significant(P<0.05);There was no statistically significant difference in preoperative and final follow-up scores between the two groups(P>0.05).No Trendelenburg sign or claudication was observed in the follow-up patients.Conclusion:1.There was no significant difference in the clinical efficacy of THA in the treatment of DDH with biological acetabular prostheses placed in appropriate upward positions(<15 mm)and anatomical positions,and both achieved good mid-term clinical efficacy.2.It is feasible to place the biological acetabulum with appropriate upward movement(<15 mm)and try not to place the acetabular prosthesis in a lateral position as much as possible.