Why do muscles become stiff in cases of lumbar disc herniation?

Lumbar disc disease is a group of neurological reflex disorders caused by compression of the subligamentous tissues of the annulus fibrosus by vertebral bodies, leading to disc protrusion that impinges upon the spinal canal’s nervous system and the neural structures within the bilateral lateral recesses. Lumbar disc herniation is a common condition primarily resulting from degenerative changes in the lumbar intervertebral disc muscles, tears in the annulus fibrosus, or displacement (herniation) of the nucleus pulposus—thereby irritating or compressing spinal nerves and/or the spinal cord, causing edema and resulting in low back and leg pain. Its onset is strongly associated with trauma, excessive physical strain, prolonged maintenance of a single posture, and degenerative spinal changes. Diagnosis can be confirmed via non-contrast CT scanning or routine orthopedic physical examination. Conservative management is recommended as initial treatment and includes: - Application of abdominal heat therapy three times daily, each session lasting at least 30 minutes; - Concurrent acupuncture and traditional Chinese medicine (TCM) therapies; - Strict bed rest on a firm mattress, with attention to keeping warm; - For severe pain, oral administration of ibuprofen (e.g., Fenbid®), one capsule twice daily after meals—providing effective analgesia. If conservative treatment proves ineffective, minimally invasive procedures such as percutaneous disc nucleoplasty (ablation) or conventional surgical intervention may be considered. Additionally, patients should increase intake of fresh vegetables and fruits, avoid greasy, spicy, and irritating foods—especially on an empty stomach—and minimize late-night activity. Regular physical exercise is encouraged to enhance overall immunity and physical resilience.