Three-dimensional distribution of subchondral fracture lines in osteonecrosis of the femoral head.

Objective: To investigate the characteristics of three-dimensional distribution of subchondral fracture lines on the surface of the osteonecrosis femoral head, and to discuss the underlying mechanisms that contribute to its collapse.

Methods: We retrospectively analyzed computed tomography (CT) images from 75 patients (comprising a total of 77 femoral heads) diagnosed with Association Research Circulation Osseous (ARCO) stage IIIA or IIIB femoral head necrosis. The three-dimensional structures of both the femoral head and the subchondral fracture line were reconstructed and subsequently fitted into normal femoral head model.

Endemic medicinal plant distribution correlated with stable climate, precipitation, and cultural diversity.

Medicinal plants provide crucial ecosystem services, especially in developing countries such as China, which harbors diverse endemic medicinal plant species with substantial cultural and economic value. Accordingly, understanding the patterns and drivers of medicinal plant distribution is critical. However, few studies have investigated the patterns and drivers of endemic medicinal plants distribution in China.