The information security and privacy protection of electronic health records (HER) are greatly con-cerned by healthcare administrators, healthcare providers and patients in the era of big data and cloud computing. The concepts of information security and privacy protection of HER wre defined according to the systematic investi-gation of related literature, the keys to the information security and privacy protection of HER were summarized, and the advances in research on information security and privacy protection of HER were described.

Objective To describe the pathological unit and octagonal en bloc resection for the treatment of ossification ligamentum flavum(OLF)in thoracic spine with spondylotic myelopathy.Methods Ninety-five patients from January 2002 to January 2007 were diagnosed as thoracic OLF,61 males and 34 females with an average age of 53.9 years(range,31-78 years).There were upper thoracic spine OLF in 32 cases,middle thoracic spine OLF in 24 cases and lower thoracic spine OLF in 39 cases.Single-segment OLF was found in 53 cases,double segments OLF was found in 38 cases and three segments OLF was found in 4 cases.CT scan multiplanar co-localized reconstruction was employed to detect the structure of spine with OLF.The Japanese Orthopaedic Association(JOA)lower limb motor function score,sphincter function score and motor function improvement rate were used to evaluate the outcomes.Results CT scan was engaged to observe 141 OLF pathological unite.The OLF pathology unit was defined as all the spine structures between the extension lines of the lower margin of the OLF two adjacent pedicles.Each OLF associates with an OLF pathology unit.The mean follow up duration was 38.3 months(range,24-60 months).Among 86 patients with sensations disturbance before operation,67 totally recovered and 19 relieved after operation.Trunk restrictions in 69 cases before operation were completely recovered after operation.Postoperative JOA sphincter function score was 2.651±0.334,comparing with preoperation score(2.262±0.561),and the difference was statistically significant.Postoperative JOA motor function score was 3.694±0.429,which was significantly increased than preoperative score 1.539±0.873,and motor function recovery rate was 87.57%.There was excellent in 71 cases,good in 17 cases and fair in 5 cases.The excellent and good rate was 94.74%.Conclusion The octagonal en block resection is relative safe for treatment thoracic OLF with myelopathy.Pathological unit of OLF in thoracic spine is more accurate to summarize the pathological contents and features of the OLF and its adjacent structure.

Objective To introduce the surgical strategy of enlarged laminectomy (with partial facet joint dissection to expose the nerve root), and to discuss its benefit for cervical ossification of the posterior longitudinal ligament(OPLL) with myelopathy. Methods Totally 82 patients with cervical OPLL were treated by enlarged laminectomy from January 1998 to December 2005. There were 47 males and 35 females, with an average age of 57 years (ranged, 39-84 years). Among them, there were 31 cases of the solitary type, 40 cases of the continuous type, and 11 cases of the mixed type. JOA scoring system and the visual analogue scale (VAS) scoring were applied to evaluate the neurological function and neck/shoulder pain respectively.Ishihara method was employed to measure cervical curvature index(CCI). The degree of spinal cord backward expanding and displacement were calculated in MR1. Results The mean decompression length was 5.2 (4-6) segments. The mean follow-up duration was 41 months (ranged, 13-58 months). JOA score has improved from 10.9(7-15) preoperatively to 13.9(11-17) postoperatively (t=14.65, P＜0.01). The excellent and good rate was 98.7%. The palsy of C5 nerve root occurred in only 2 patients, both recovered after surgery. Zhe mean postoperative VAS score was 1.4(1-3), comparing with the preoperative score of 5.3 (4-6). The pain in neck/shoulder was alleviated obviously (t=15.46, P＜0.01 ). CCI decreased from 18.8% to 10.5%(t=5.03, P＜0.01 ),but did not follow by neuron function deterioration. MRI indicated that the cross-sectional area at the level of maximum compression of the dural sac increased from 85.4 mm2 preoperatively to 153.8 mm2 postoperatively (t=16.33, P＜0.01), and the mean spinal cord posterior shift was 6.2 mm (t=15.35, P＜0.01). Conclusion The enlarged laminectomy is proved to be effective in treating cervical OPLL, in terms of significant posterior shift of the spinal cord, relief of cervical/shoulder pain, lower rate of the palsy of C5 nerve root, with no recurrence of spinal cord compression symptom.

Objective To evaluate the surgical strategy of decompression via posterior-anterior approach and anterior fixation in treatment fracture-dislocation of the lower cervical spine with bilateral facet joints dislocation. Methods This study retrospectively reviewed 37 cases of lower cervical spine fracture with bilateral joints dislocation. There were 21 males and 16 females with an average age of 42 years (19-58). Distraction-flexion stage 3(DFS 3) were found in 24 cases and DFS 4 in 13 cases. All the cases were diagnosed by X-ray, CT and MRI and confirmed during the surgery. Decompression via posterior-anterior approach and anterior fixation had been adapted as the surgical strategy. The NASCIS and IMSOP standard were applied to definite the level of cervical spinal cord injury. The ASIA grading was used for evaluation the spinal cord function and the recovery rate. The X-ray and CT were used to observe reduction and bone fusion. Results The mean operative time was (4.5:±0.5) h, and the mean amount of blood loss was 360 ml (200-500 ml). All the incision healed. The two segments fixation was used in 23 cases, 3 segments fixation in 13 cases, and 4 segments fixation in 1 case. The mean follow-up period was 32 months (16-45 months).Postoperative X-ray and CT showed that bone fusion was achieved in all patients within 4-8 months, without graft displacement, or failure of implants. Spinal cord function did not aggravate, and sensory recovery ranged from 7 to 20 levels (averaged, 12.7). The ASIA grade were improved with an average of one grade. Conclusion To treat fracture-dislocation of the lower cervical spine with bilateral facet joints dislocation, the posterlor-anterior approach and anterior fixation/fusion was benefit to preservation the cervical spinal cord function and reconstruction biomechanical stability of the cervical spine.