Table 1 Inclusion and exclusion criteria

Inclusion criteria

Central, paracentral, or prolapsed L5–S1 disc herniation

Symptoms of low back pain and leg pain

Failure of formal conservative treatment

Exclusion criteria

Lumbar instability, such as lumbar spondylolisthesis

Intervertebral disc inflammation or tuberculosis

Severe lumbar stenosis, and far lateral disc herniation

Previous surgery at the lumbar spine

Multiple segments of disc herniation

Recurrent disc herniation

Pregnant or syndrome of cauda equina

Severe cardiac disease, active neoplasm, anaemia, or any other surgical contraindications