To conduct a prospective, single-center, self-controlled, clinical trial to verify the efficacy and safety of K-Rod dynamic stability system in the repair of lumbar degenerative diseases following 2 years follow-up, aiming to provide references for clinical treatment of lumbar degenerative diseases.

Posterior internal fixation and fusion systems are still one of the main methods for the treatment of chronic back pain due to intervertebral disc degeneration, but adverse reactions, such as accelerated regression of adjacent segments, are often inevitable during the treatment.

At present, various pedicle screw-based posterior dynamic stability systems of the lumbar spine have become an alternative fusion therapy for lumbar degenerative diseases. Dynamic stability is defined to reduce the loading on the intervertebral disc/articular surfaces, to maintain movement under mechanical load, to limit the abnormal movement of the spinal segment, and to reduce the stress on the bone-screw interface dynamically and stably. An ideal fixation system will be stable enough to maximize the fusion rate without the need for excessive rigidity, as well as to maintain maximum load and physiological posture of the vertebral segment, thereby reducing the horizontal stress of the adjacent segment.

Inclusion Criteria:

• Degenerative lumbar spondylolisthesis (degree I)
• Nerve root canal or central spinal canal stenosis
• Accompanying nerve root pain and/or chronic back pain
• 32-76 years old
• Regardless of gender
• All patients or family members signed the informed consent

Exclusion Criteria:

• Systemic infection;
• Poor compliance and inability to complete the trial