Discogenic pain is a common cause of chronic spinal pain, accounting for approximately 20% to 40% of chronic neck and back pain cases. This article explains its causes, symptoms, diagnostic methods, and treatment options.
Discogenic Pain: The Overlooked Root of Spinal Pain
When discussing neck and back pain related to spinal discs, many people immediately think of a slipped disc (herniated disc) or sciatica. However, the disc itself is a major source of spinal pain. According to medical research, discogenic pain accounts for approximately 20% to 40% of both chronic lower back pain and chronic neck pain cases.
Structure and Function of Spinal Discs
Spinal discs are located between the vertebrae (the bones of the spine) and act as shock absorbers during daily activities. Structurally, the outer layer is a tough, fibrous ring, while the inner core is a jelly-like substance filled with water to help distribute pressure evenly.
In a healthy disc, sensory nerves only exist in the outermost layer of the fibrous ring and do not reach the centre. As a result, you do not feel pain when the disc is compressed during normal movement. Furthermore, discs do not have a direct blood supply. They rely on osmosis (the passive transfer of fluids) for their nutrients, making them particularly prone to degeneration and difficult to heal naturally.
Causes of Discogenic Pain
With age and long-term wear and tear, the inside of the disc begins to change. It gradually loses water, and the rate of cell destruction overtakes cell regeneration. Inflammatory factors (such as TNF-α and IL-1β) become more active, and the outer fibrous ring becomes fragile or even tears.
Moreover, a degenerating disc releases Nerve Growth Factor (NGF). This chemical encourages sensory nerve fibres to grow inwards from the outer edge deep into the disc. Once these nerves invade the previously painless core, ordinary movements like bending over or prolonged sitting will directly trigger pain.
Risk Factors for Accelerated Degeneration
Current medical research identifies several factors that can accelerate disc degeneration and lead to chronic neck or back pain. These include prolonged sitting, poor posture when lifting heavy objects, weak core muscles, smoking, obesity, spending long periods looking down at a mobile phone, and genetic factors.
Clinical Symptoms
Patients with lumbar (lower back) discogenic pain typically experience a dull ache in the lower back. This pain significantly worsens after sitting for 30 to 60 minutes and is aggravated by bending forward or lifting heavy objects. However, lying down flat quickly relieves the discomfort. Some patients experience referred pain that extends into the buttocks and thighs, though it usually does not travel below the knee, which often leads to a misdiagnosis of sciatica.
Patients with cervical (neck) discogenic pain often develop deep, aching pain in the neck and upper shoulder blades after sitting or looking down for extended periods. In severe cases, this pain can radiate down the arm. While stretching or massages may offer temporary relief, true comfort is usually only found when lying down.
For both neck and lower back discogenic pain, neurological examinations typically show normal results, and MRI scans confirm that no nerves are being compressed.
Diagnosis
Diagnosing discogenic pain is challenging because the degree of degeneration seen on scans does not always match the level of pain a patient feels. A doctor will first carefully review your symptoms before arranging an MRI scan to assess the extent of disc degeneration, look for any tears in the fibrous ring, and check for inflammation in the endplates (the areas connecting the disc to the bone).
The gold standard for confirming discogenic pain is a procedure called provocative discography. Under X-ray guidance, the doctor inserts a fine needle into the targeted disc and injects a contrast dye. If this safely recreates your familiar pain, and a neighbouring healthy disc shows no such reaction, a diagnosis of discogenic pain is confirmed.
Treatment Options
Treatments for discogenic pain generally progress from low-risk to higher-risk interventions. Doctors usually begin with conservative treatments, which include targeted exercise therapies (such as the McKenzie method or core strengthening), medications, or acupuncture.
If conservative treatments fail, interventional therapies may be considered. A particularly notable option is regenerative therapy. This involves injecting the patient’s own Platelet-Rich Plasma (PRP) or Bone Marrow Aspirate Concentrate (BMAC) directly into the disc. This treatment uses high concentrations of natural growth factors to control inflammation and promote the repair of disc cells. Since the fundamental cause of discogenic pain involves cell destruction and chronic inflammation, regenerative therapy directly targets these root problems. While multiple medical studies support the effectiveness of regenerative therapies for discs, it remains a relatively new treatment, and the medical community has not yet reached a complete consensus.
Other interventional options include radiofrequency nerve ablation. This technique uses heat to disable the sensory nerves supplying the disc, targeting either the nerves inside the disc or the surrounding nerves. For highly stubborn discogenic pain, spinal cord stimulation may also be considered.
If all other treatments fail, patients might need to consider surgery, such as a lumbar spinal fusion or an anterior cervical discectomy and fusion (a neck surgery). However, it is worth noting that some studies show lumbar fusion surgery yields similar results to intensive conservative treatment, meaning the decision to operate must be considered very carefully.
Conclusion
Discogenic pain is a common yet easily overlooked condition, primarily caused by the wear and tear of spinal discs. Treatment ranges from conservative care to interventional therapies and surgery. To prevent this condition, it is vital to maintain a good sitting posture, use proper lifting techniques, strengthen your core muscles, and stop smoking. If you are suffering from long-term neck or lower back pain, it is highly recommended to consult a pain medicine specialist early on to identify the root cause and receive the right treatment.
Dr. Lee Yuk-ming
Specialist in Pain Medicine
