Comparative Study Of Leg Length Discrepancy And Body Sagittal Balance Of Adult Crowe Type ? DDH After Osteotomy Or Non-osteotomy THA

ObjectiveTo investigate the improvement of hip joint function,body sagittal balance,and leg length discrepancy(LLD)in adults with unilateral Crowe type IV DDH after osteotomy or non-osteotomy total hip arthroplasty(THA),and to evaluate the curative effect of osteotomy or non-osteotomy THA,providing reference for clinical application.Materials and methodsA retrospective analysis was conducted including 30 patients with unilateral Crowe type ? DDH who underwent THA treatment in the Department of Orthopedics of Shandong Provincial Hospital from October 2016 to June 2019.They were divided into two groups according to the with or without osteotomy in THA.Group A was the osteotomy group with 22 cases,and the osteotomy method was selected subtrochanteric osteotomy.Group B was the non-osteotomy group with a total of 8 cases.Normotopia X-ray films of pelvic and full-length of both lower extremities,and full-spinal lateral x-rays were collected before,3 and 6 months after surgery.Sagittal parameters including spinal tilt(ST),lumbar lordosis(LL),sagittal vertical axis(SVA),pelvic incidence(PI),pelvic tilt(PT),sacral slope(SS),sacrum pubic incidence(SPI),sacrum femoral angle(SFA),pelvic femoral angle(PFA),and femoral inclination(FI)were measured and compared.Then leg length discrepancy were measured and compared.And the general condition and Harris score of patients before and after surgery were recorded and compared.Results1.General conditionThere were 1 male and 29 female patients,with an average age of 45.42±7.98(24-65)years.The differences in age and sex distribution between the two groups were not statistically significant.No patient had serious complications.2.Improvement of hip joint functionHarris score was 33.4 ± 4.7 points(26-37 points)before operation,and 89.4 ± 4.1 points(82-93 points)6 months after operation in group A.Harris score was 32.9 ± 5.2 points(25-39 points)before operation,and 88.8±4.7 points(84-94 points)6 months after operation in group B.The difference in each group was statistically significant(P<0.05).The difference in Harris score between group A and group B was not statistically significant.3.Improvement of LLDLLD of 3 and 6 months after surgery were significantly improved compared with that before surgery.At 6 months after surgery,LLD of group A and B decreased from 40.5±6.3mm(29.7-48.7mm),37.8± 7.0mm(27.8-48.2mm)to 10.4 ± 6.1mm(0.3-17.5mm),and 6.4 ± 5.6mm respectively(0.3-13.4mm).And there was statistically significant difference in postoperative LLD between the two groups(P<0.05).The limb lengthening of the affected limb in groups A and B was 27.2 ± 6.0mm and 32.7± 5.1mm,and the difference between the two groups was statistically significant(P<0.05).4.Improvement of body sagittal balance? At 3 months after operation,SVA(3.75 ± 1.20cm),SS(38.23± 7.02°),FI(2.02 ±1.03 °)of group A,and LL(39.77± 1.97?),SVA(2.51 ± 2.58cm),SS(38.23 ± 7.02°),FI(2.02 ± 1.03°),and ST(87.52 ± 4.21°)of group B had statistically significant differences compared with those before surgery(P<0.05).? At 6 months after operation,LL(39.97±2.47°),ST(88.17±4.11°),SVA(2.85±1.33cm),SS(37.68±6.85°),FI(1.97±1.29°),PI(52.24±3.28°)of group A,and SFA(45.98±3.46°),LL(40.29±2.98°),ST(89.26±3.53?),SVA(2.19±1.94cm),SS(37.19±6.27),FI(2.06±1.45°)of group B had statistically significant differences compared with those before surgery(P<0.05).?There was no significant difference in the parameters between the two groups before the surgery.At 3 months after operation,the difference of ST,LL,and SVA between group A and B were statistically significant(P<0.05).At 6 months after operation,the difference of SVA between the two groups was statistically significant(P<0.05).ConclusionOsteotomy or non-osteotomy THA are both safe and effective for Crowe type ?DDH patients,which can significantly improve hip function and LLD.However,non-osteotomy THA can provide smaller LLD and more significant limb lengthening.Both methods can effectively improve the sagittal balance of the body.The non-osteotomy group has more significant improvements in spinal anteversion in the short term after surgery.Full consideration should be given to the changes in sagittal balance of the patient's body after surgery to adj ust the placement of the prosthesis in order to obtain long-term clinical benefits.