The study is designed for evaluating the presence of mesenchymal stem cells of vertebral disc. Isolation and authentication of these cells may be applied for the vertebral disc regeneration and the research tissue engineering.

We will collect the degenerative disc from adults and isolate the mesenchymal stem cell-like precursors cells. The function of osteogenic, chondrogenic, and lipogenic differentiation will be authenticated. The results will offer the information for cell source of tissue engineering in the future.

Inclusion Criteria:

• The adults with disc degeneration（age >= 20 years old） A. Herniated intervertebral disc. B. Spondylolisthesis. C. Spondylolysis. D. Other causes of disc degeneration.

Exclusion Criteria:

• Age < 20 years old.
• Pregnancy.
• Spinal tumors.
• Spinal infections.

The patients received the surgery of discectomy for the degenerative disc.