Safety ofscrew placement for severe spinal deformity with the use of O-arm three-dimensional computer-assisted navigation system / 中国组织工程研究

BACKGROUND:O-arm navigation integrates CT image quality and the flexible mobility of the C-arm. Surgery for severe spinal deformity is very difficult, with high incidence of nerve injury, so it is a chalenging surgery for spinal surgery. The role of O-arm in the correction of spinal deformity is particularly important. OBJECTIVE:To explore the effect and safety of pedicle screw placement in severe spinal deformity under the guidance of O-arm navigation system. METHODS:Clinical data of 25 patients with severe spinal deformity with the aid of O-arm navigation were retrospectively analyzed. We observed pedicle screw insertion, operation time, intraoperative blood loss, correction of scoliosis and correction of kyphosis, and assessed the safety of screw insertion. RESULTS AND CONCLUSION:(1) Totaly 326 pedicle screws were implanted in 25 patients. According to NEO classification, 280 pedicle screws (92%) belonged to grade 0 (no perforation of pedicle cortex). Grade 1: perforation of pedicle cortex, 2 mm, 4 mm, including 0 screw (0%). (2) Operation time was (272.3±17.3) minutes. Intraoperative blood loss was (1 710.0±229.1) mL. (3) Cobb angle of scoliosis was changed from (70.5±6.0)° preoperatively to (22.8±4.8)° postoperatively. Cobb angle of kyphosis was changed from (72.0±5.2)° preoperatively to (28.1±5.7)° postoperatively. Significant differences were detected (P< 0.05). (4) These findings verify that with the guide of the O-arm navigation system, the accuracy of screw insertion is high. The risk of intraoperative nerve injury was reduced. The scoliosis and kyphosis deformity were improved effectively.

Electroacupuncture of 2 Hz induces long-term depression of synaptic transmission in the spinal dorsal horn in rats with neuropathic pain / 北京大学学报(医学版)

Objective: To observe the effect of 2 Hz electroacupuncture (EA) on long term depression (LTD) of synaptic transmission in the spinal dorsal horn in rats with neuropathic pain, so as to explore the central mechanisms of the antinociceptive effects of 2 Hz electroacupuncture on neuropathic pain. Methods: The neuropathic pain models were produced by tight ligation of the L5/L6 spinal nerves in Sprague Dawley rats. The C fiber evoked field potentials in the spinal dorsal horn were recorded with extracellular recording techniques. The parameters of the electroacupuncture were as follows: frequency of 2 Hz, wavelength of 0.6 ms, intensity of 1,2,3 mA lasting 10 min for each intensity, stimulation time of 30 min. The positive stimulating electrode was placed in acupoint “sanyinjiao” and the negative electrode in “zusanli”. Results: (1) 2 Hz electroacupuncture significantly decreased the amplitudes of C fiber evoked field potentials in the spinal dorsal horn in rats with neuropathic pain to (49.4?0.6)% of the control, compared with that (100.1?1.2) % of the control before EA (unpaired t test, P