BACKGROUND: Recent studies have found that oxidative stress plays an important role in osteoporosisOsteoporosis is closely related to aging, estrogen deficiency, nuclear factor E2 related factor 2, heme oxygenase 1 and reactive oxygen species production. OBJECTIVE: To explore the protective mechanism of Zuogui Pill on oxidative stress injury of osteoblasts. METHODS: The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Harbin Medical University. Osteoblasts were isolated and cultured from the skull of neonatal Sprague-Dawley rats, and were divided into three groups: Control group, model group and Zuogui Pill group. The oxidative stress injury model of osteoblasts was established with 300 μmol/L H2O2 in the model and Zuogui Pill groups. Osteoblasts in the Zuogui Pill group were cultured with Zuogui Pill containing serum, and the control group did not undertake any treatment. Levels of malondialdehyde and superoxide dismutase in osteoblasts were determined. The expression of nuclear factor E2 related factor 2 and heme oxygenase 1 protein in osteoblasts was detected by western blot. RESULTS AND CONCLUSION: Compared with the control group, the content of malondialdehyde increased significantly, and the level of superoxide dismutase decreased significantly in the model group. Compared with the model group, the content of malondialdehyde decreased significantly and the level of superoxide dismutase increased significantly in the Zuogui Pill group. Western blot results showed that nuclear factor E2 related factor 2 and heme oxygenase 1 expression in osteoblasts of the model group increased significantly compared with the control group, and the expression of nuclear factor E2 related factor 2 and heme oxygenase 1 in osteoblasts of Zuogui Pill group was significantly higher than that of the model group. To conclude, Zuogui Pill can protect osteoblasts from oxidative stress injury.

Objective: To evaluate one-stage repair of leg open fracture with soft tissue defect by fixation plus skin flap. Methods: From January 2011 to January 2018, 34 patients with leg open fracture plus soft tissue defect were treated at Department of Orthopedics, The Second Affiliated Hospital to Harbin Medical University. They were 31 males and 3 females, aged from 13 to 54 years(average, 35 years). According to the Gustilo classification, the defects were type ⅢA in 31 cases and type ⅢB in 3 cases. The wound size ranged from 6 cm×3 cm to 25 cm×10 cm. All patients were treated with emergency fracture fixation and flap repair by one stage after thorough debridement. Internal bone plating was performed in 32 patients and external fixation at a single arm in 2 patients. All defects were repaired with a free anterolateral thigh flap. Flap survival, vascular crisis and bone infection were followed up postoperatively. Results: All the free flaps survived in the 34 cases with no vascular crisis. These patients were followed up for 6 months to 3 years (average, 10 years). The flaps healed well, with good appearance and soft texture. No bone infection occurred at the defective sites. After postoperative rehabilitation, the knee extension ranged from 160° to 180°, knee flexion from 90° to 110°, ankle dorsal extension from 90° to 110°, and ankle plantar flexion from 100° to 120°. Conclusion Soft tissue defects in leg open fracture can be effectively treated by flap repair after thorough debridement at the same time of fracture fixation, because the primary wound healing can avoid infection and lead to fine survival of the flap.