Subchondral bone deterioration in femoral heads in patients with osteoarthritis secondary to hip dysplasia: A case–control study

• Main Authors: Guangyi Li, Lianzhi Chen, Qiujian Zheng, Yuanchen Ma, Changqing Zhang, Ming Hao Zheng
• Format: Article
• Language: English
• Published: Elsevier 2020-09-01
• Series: Journal of Orthopaedic Translation
• Subjects: Bone remodelling; Hip dysplasia; Microarchitecture; Osteoarthritis; Osteoporosis
• Online Access: http://www.sciencedirect.com/science/article/pii/S2214031X19302268

Objectives: Residual hip dysplasia is the most common underlying condition leading to secondary osteoarthritis (OA) of the hip. Subchondral bone alterations in OA secondary to hip dysplasia (HD-OA) are poorly investigated. The aim of the present study was to analyse the microarchitecture, bone remodelling and pathological alterations of subchondral bone in femoral heads from patients with HD-OA. Methods: Subchondral bone specimens were extracted from both weight-bearing and non–weight-bearing regions of femoral heads from 20 patients with HD-OA and 20 patients with osteoporotic femoral neck fracture, during hip replacement surgery. Micro-CT and histological examination were performed to assess the microarchitecture and histopathological changes. Results: The weight-bearing subchondral bone showed significantly more sclerotic microarchitecture and higher bone remodelling level in HD-OA as compared with osteoporosis. In the non–weight-bearing region, the two diseases shared similar microarchitectural characteristics, but higher bone remodelling level was detected in HD-OA. Distinct regional differences were observed in HD-OA, whereas the two regions exhibited similar characteristics in osteoporosis. In addition, HD-OA displayed more serious pathological alterations, including subchondral bone cyst, metaplastic cartilaginous tissue, bone marrow oedema and fibrous tissue, especially in the weight-bearing region. Conclusions: Osteoarthritic deteriorations of subchondral bone induced by hip dysplasia spread throughout the whole joint, but exhibit region-dependent variations, with the weight-bearing region more seriously affected. Biomechanical stress might exert a pivotal impact on subchondral bone homeostasis in hip dysplasia. The translational potential of this article: The histomorphometric findings in the project indicate an early intervention for the development of hip dysplasia in clinic.