Yin Zhuang, Jun Lin and Huilin Yang
Michael G. Fehlings and Babak Arvin
Liang Chen, Huilin Yang, Tongqi Yang, Yaozeng Xu, Zhaohua Bao and Tiansi Tang
The authors undertook a study in patients with traumatic central cord syndrome (TCCS) who underwent surgical intervention. They retrospectively assessed the motor score improvement and functional status and identified prognostic predictors of improvement.
Between March 1999 and May 2004, 49 patients with TCCS were surgically treated. Motor scores were collected at admission and follow-up using the American Spinal Injury Association (ASIA) Impairment Scale. The 36-Item Short Form Health Survey (SF-36) was administered. Other parameters including walking index, spasticity, bladder management, and neuropathic pain scores were recorded. Patients were asked to assess their level of satisfaction with their final symptoms.
The average ASIA score, converted into numeric values, was increased from 54.9 at admission to 81.9 and 89.6 at 6 months and final follow-up, respectively. Significant improvement of ASIA score was achieved within the first 6 months of surgery. No significant difference was found between patients who underwent surgery within 4 days of injury or after 4 days of injury, adopting different approaches (anterior, posterior, or a combination), or with different pathological entities (acute disc herniation, fracture or dislocation, or multilevel degeneration). The ASIA score improvement had a positive correlation with the age at injury (r = 0.505, p = 0.023). The SF-36 data at 6 months and final follow-up were not as satisfactory as the improvement in ASIA scores, and almost one-third of patients expressed dissatisfaction with their final symptoms. For patients who were older than 65 years at injury, the mean follow-up Walking Index for Spinal Cord Injury (WISCI) score was statistically lower than it was in younger patients. The presence of spasticity or neuropathic pain at follow-up was not related to age, sex, ASIA motor score, or WISCI outcome.
Surgical intervention can be safely applied in patients with TCCS. Significant improvement of ASIA score was achieved during the first 6-month period of follow-up. Factors including type of lesion, timing of surgery within or after 4 days of injury, and surgical approach were not significantly associated with final ASIA score. The improvement in the ASIA motor score was positively correlated with age at injury. No significant correlation was found between or among the presence of spasticity, neuropathic pain, and ASIA score at final visit. Almost one-third of patients were not satisfied with their final symptoms.
Jing Wang, Tiansi Tang, Huilin Yang, Xiaoshen Yao, Liang Chen, Wei Liu and Tao Li
The nucleus pulposus has been reported to be an immunologically privileged site. The expression of Fas ligand (FasL) on normal and herniated lumbar disc cells has been reported. The relationship between a physiological barrier and the role of FasL has not yet been addressed. To clarify this relationship and to investigate a possible pathogenesis of intervertebral disc degeneration (IDD), the expression of Fas and FasL (a mean apoptosis index) on normal and stabbed-disc cells was examined in a rabbit model of IDD.
Using defined needle gauges and depths, the anular puncture model of IDD was established in rabbits. The normal and stabbed discs were harvested at 3, 6, and 10 weeks after surgery. Immunohistochemical staining of these discs for Fas and FasL was performed using standard procedures. The mean apoptosis indices of the disc cells were determined using flow cytometry analysis.
The nucleus pulposus cells from the normal discs exhibited relatively weak immunopositivity, whereas the nucleus pulposus cells from the stabbed discs exhibited strong immunopositivity. There was a significant difference (p < 0.001) in the percentage of FasL-positive nucleus pulposus cells between the normal discs and the stabbed discs. The mean apoptosis indices of the stabbed-disc cells at 3, 6, and 10 weeks poststab were significantly higher than those in normal disc cells (p < 0.001, 0.002, and 0.006, respectively). There was a significant correlation between the degree of FasL-positive expression and the degree of Fas-positive expression of the nucleus pulposus cells poststab (r = 0.571, p = 0.0036).
These observations indicate that the nucleus pulposus is an immunologically privileged site. This immunological privilege is maintained by FasL and the physiological barrier together. When the physiological barrier was damaged (by stabbing the disc), the role of FasL changed, and FasL was coexpressed with Fas to induce apoptosis of disc cells. These results indicate that an autoimmune reaction may be a possible pathogenesis of IDD.