Low-intensity pulsed ultrasound: a potential non-invasive therapy for femoral head osteonecrosis.

The osteonecrosis of femoral head (ONFH) has been a common disorder in clinical orthopaedic practice. ONFH is the relative contraindication of hip arthroplasty for the young and active patients since they suffer a high rate of revision and inferior function postoperatively. The primary importance in therapy is to prevent the progression of the disease and the collapse of the articular surface in order to keep away from hip arthroplasty. Low-intensity pulsed ultrasound (LIPUS) has been indicated to enhance the osteogenic differentiation of mesenchymal stem cells, stimulate the differentiation and the proliferation of osteoblasts, inhibit osteoclasts, improve the local blood perfusion and the angiogenesis, and accelerate the healing process of the stress fracture. We present a hypothesis that LIPUS may be an appropriate non-invasive modality for bone repair in the early stage of ONFH so that the progressive collapse of the articular surface and the subsequent arthroplasty would be avoided.