Primary cilia respond to intermittent low-magnitude, high-frequency vibration and mediate vibration-induced effects in osteoblasts.

Our objective was to investigate the role of primary cilia in low-magnitude, high-frequency vibration (LMHFV) treatment of MC3T3-E1 osteoblasts (OBs). We used chloral hydrate (CH), which has a well-characterized function in chemically removing primary cilia, to elucidate the role of primary cilia in LMHFV-induced OB osteogenic responses through cell viability assay, Western blot analysis, real-time quantitative RT-PCR, and histochemical staining methods. We observed a significant, 30% decrease in the number of MC3T3-E1 OBs with primary cilia (reduced from 64.3 ± 5%) and an approximately 50% reduction in length of primary cilia (reduced from 3 ± 0.8 µm) after LMHFV stimulation. LMHFV stimulation upregulated protein expression of the bone matrix markers collagen 1 (COL-1), osteopontin (OPN), and osteoclacin(OCN) in MC3T3-E1 OBs, indicating that LMHFV induces osteogenesis. High-concentration or long-duration CH exposure resulted in inhibition of MC3T3-E1 OB survival. In addition, Western blot analysis and RT-PCR revealed that CH treatment prevented LMHFV-induced osteogenesis. Furthermore, decreased alkaline phosphate activity, reduced OB differentiation, mineralization, and maturation were observed in CH-pretreated and LMHFV-treated OBs. We showed that LMHFV induces morphological changes in primary cilia that may fine-tune their mechanosensitivity. In addition, we demonstrated the significant inhibition by CH of LMHFV-induced OB mineralization, maturation, and differentiation, which might reveal the critical role of primary cilia in the process.

Traumatic anterior hip dislocation with associated bilateral femoral fractures in a child: a case report and review of the literature.

Traumatic anterior hip dislocation is rare, because the hip joint is a highly stable joint. It is extremely rare for the anterior hip dislocation with combined bilateral femoral fracture in children. We present a case of 7-year-old boy with traumatic anterior hip dislocation with associated bilateral femoral fractures. Radiographic examination showed the right femoral head was dislocated anteroinferiorly. The ipsilateral femoral shaft showed a transverse femoral shaft fracture and proximal and distal femoral bifocal fractures of the contralateral femur. The dislocation of the right hip was reduced 10 hours after the injury in local hospital. One week later, the right femoral shaft fracture and left proximal femoral fracture were open reduced and internally fixed with plate and screws and the distal left femoral fracture was closed reduced and fixed with Kirschner wires. Postoperatively, active hip flexion and extension to recover hip and knee movement were then permitted but without weight bearing for 3 months. Radiographs at 3 months, at 6 months showed the fractures healed well and hardware were removed respectively. However, irregularities of the femoral head meaned avascular necrosis of the femoral head. This case stresses the importance of a rapid evaluation and treatment for the dislocation of the hip, providing a stable reduction and a firm internal fixation of the associated fractures.

Comparison of internal fixation with Gamma3 Long nails and INTERTAN nails in the treatment of Seinsheimer type V subtrochanteric femoral fractures in elderly patients.

The aim of this study was to clinically compare the therapeutic effects of internal fixation using a third-generation Gamma Long Nail (TGLN) with that of INTERTAN in the treatment of Seinsheimer Type V subtrochanteric femoral fractures in elderly patients.The therapeutic effect of internal fixation with TGLN, compared with that with INTERTAN, was retrospectively analyzed in elderly patients diagnosed with Seinsheimer Type V subtrochanteric fracture. Twenty-five cases were divided into 2 groups based on the fixation devices: the TGLN group (13 cases; 5 men and 8 women) and the INTERTAN group (12 cases; 5 men and 7 women). Patients were followed up postoperatively, and their clinical history, intraoperative blood loss, fracture healing, Harris Hip Scores, and postoperative complications were recorded and compared.Patients in the TGLN group had shorter operation time and less intraoperative blood loss, compared with those in the INTERTAN group (P < .05). There were no significant between-group differences in postoperative complications, fracture healing time and Harris Hip Scores during the follow-up (P > .05).