Acetabular Morphology in Patients with Developmental Dysplasia of the Hip with High Dislocation

The Validation of Two-Dimensional and Three-Dimensional Radiographic Measurements of Host Bone Coverage in Total Hip Arthroplasty for Hip Dysplasia: A Comparison with Intra-Operative Measurements

Several methods have been introduced to measure the host bone coverage of the acetabular component after total hip arthroplasty (THA). The aims of this study were (1) to validate two-dimensional- and three-dimensional-based host bone coverage measurements by comparing intra-operative measurements, and (2) to determine the minimum host bone coverage for achieving stable cup fixation after THA in hip dysplasia. The clinical outcomes of each patient were evaluated during their final follow-up period using the Harris Hip score (HHS). The coverage of the host bone was analyzed by comparing 2D-based, 3D-based, and intraoperative assessments. The mean HHS was increased significantly from 60.84 ± 14.21 pre-operatively to 93.13 ± 4.59 (p < 0.0001). The host bone coverage ratio measured intraoperatively was 83.67 ± 3.40%, while the ratio measured by 3D CT reconstruction was 82.72 ± 3.59%. There was a strong positive correlation between the intra-operative host bone coverage and the 3D-based one (r = 0.826, p < 0.0001). It is recommended that 3D-based measurements are used to evaluate the host bone coverage after THA in patients with hip dysplasia. In addition, achieving a minimum host bone coverage of 75% is recommended for the attainment of stable cup fixation.

Total Hip Arthroplasty in Patients with Crowe III/IV Developmental Dysplasia of the Hip: Acetabular Morphology and Reconstruction Techniques

The severe anatomic deformities render acetabular reconstruction as one of the greatest challenges in total hip arthroplasty (THA) for patients with Crowe III/IV developmental dysplasia of the hip (DDH). Thorough understanding of acetabular morphology and bone defect is the basis of acetabular reconstruction techniques. Researchers have proposed either true acetabulum position reconstruction or high hip center (HHC) position reconstruction. The former can obtain the optimal hip biomechanics, including bulk femoral head autograft, acetabular medial wall displacement osteotomy, and acetabular component medialization, while the latter is relatively easy for hip reduction, as it can avoid neurovascular lesions and obtain more bone coverage; however, it cannot achieve good hip biomechanics. Both techniques have their own advantages and disadvantages. Although there is no consensus on which approach is better, most researchers suggest the true acetabulum position reconstruction. Based on the various acetabular deformities in DDH patients, evaluation of acetabular morphology, bone defect, and bone stock using the 3D image and acetabular component simulation techniques, as well as the soft tissue tension around the hip joint, individualized acetabular reconstruction plans can be formulated and appropriate techniques can be selected to acquire desired clinical outcomes.

The Global Research Trends and Hotspots on Developmental Dysplasia of the Hip: A Bibliometric and Visualized Study

Background: Developmental dysplasia of the hip (DDH) is a common musculoskeletal disorder in newborns and also one of the most common causes of hip arthritis in women. Many topics concerning DDH still remain controversial, and the global research trend in this field has not been well-studied yet. The aim of the present study was to illustrate the overall knowledge structure, development trends, and research hotspots of DDH.

Methods: The publications related to DDH from 1998 to 2020 were identified from the Web of Science Core Collection (WOSCC). Three bibliometric tools were used to conduct visualization and knowledge maps. Annual trends of publications, contributions of countries, institutions, authors, funding agencies and journals, and clustering of keywords were analyzed.

Results: A total of 2,691 publications were included. The annual number of DDH publications showed an increasing trend worldwide. The United States has made the greatest contribution, with the largest number of publications and the highest H-index. The most prolific institutions were Shanghai Jiao Tong University, Children's Hospital of Philadelphia, and Shriners Hospital for Children. Professors Tönnis D, Harris WH, Crowe JF, Graf R, and Salter RB have made great achievements in this field. However, the collaboration between international institutions or researchers was relatively low and mainly conducted in European and American countries. All the keywords could be divided into five clusters: hip osteoarthritis study, hip replacement study, hip ultrasound study, osteotomy surgery study, and etiology study. A trend of balanced and diversified development existed in these clusters. Keywords with the ongoing bursts, including clinical outcome, risk factor, femoroacetabular impingement, predictor, arthroscopy, morphology, and anteversion may continue to be the research hotspots in the near future.

Conclusions: There will be an increasing number of publications on DDH research, and the United States stay ahead in this field. International collaboration needs to be further strengthened. The information can provide helpful references for researchers to explore hot issues or target a specific field of DDH.