Publications & Articles

Neural Prolotherapy: a new and safe treatment for musculoskeletal pain (update)

Neural Prolotherapy (NPT), also called perineural injection therapy (PIT), is a relatively new injection therapy aimed at treating neuropathic pain, a major component of chronic pain and musculoskeletal injuries. Neural Prolotherapy is the injection of a medical-grade and sterile dextrose solution, just below the skin to promote healing of cutaneous nerves and restoration of tissue function. Although the exact working mechanism is still a topic of research, it is currently believed that the dextrose works on the capsaicin (or TRPV1) pain receptors of the free nerve endings of C-fibers, omnipresent in our connective tissue. Another hypothesis, based on neurophysiological studies by McIver and his team, suggests that excessive ischaemic pressure onto nerves and C-fibers impairs supply of glucose to the nerve tissue and results in rapid firing of the C-fibers, causing pain.

When connective tissue is injured, it causes a release of pro-inflammatory substances that activate the TRPV1 channel on certain nerve endings in the C-fibers. When this channel is turned on, it results in the release of substances that cause inflammation leading to swelling, hypersensitivity, and painful sensations. This can happen following trauma or repetitive strain injury throughout the whole body as connective tissue is omnipresent.

Based on the well-studied pain-modulating effect of sweet solutions following the application of capsaicin on the tongue, it has been postulated that dextrose binds to and inhibits the TRPV1 nerve receptors, preventing this cascade and restoring normal nerve function. Furthermore, the fluid in the injection may also help to hydrate and improve sliding of connective tissue. Dehydrated connective tissue can add to nerve pain by pressing on the nerve passing through it.

Neural Prolotherapy is generally very well tolerated, even without local anesthetic. When using dextrose concentrations above 10%, i.e. classical prolotherapy, generally a local anesthetic is recommended. The injections are administered with very small and short needles just beneath the surface of the skin.  Multiple injections are performed along the course of subcutaneous nerves.  Some points may result in mild discomfort but generally, the discomfort only lasts a few minutes. Most patients notice an immediate reduction of pain after the first injection.  This initial analgesic effect may last anywhere between hours to days, allowing the patient to start an exercise program aimed at further improving tissue healing. Most patients respond to 3-4 treatments depending on how long the injury has been present as well as the degree of the damage. Treatments are typically spaced 1-2 weeks apart.

Neural Prolotherapy is considered safe when administered by a properly trained physician. Dr Praet has been applying prolotherapy since 2009 without any major side-effects. Injections are done under aseptic conditions with minimal risk of infection. For less superficial body parts or when injecting close to a nerve or large blood vessel, ultrasound guidance is sometimes required. While uncommon, possible adverse effects include local swelling, bruising and mild temporary pain.

Unfortunately, Neural Prolotherapy is currently not covered by most insurance companies.

Based on clinical experience, Neural Prolotherapy is effective in treating nerve pain associated with injuries to joints, muscles, tendons, and ligaments.  Treatment areas include the neck, back, knee, shoulder, hip, elbow, wrist (carpal tunnel), hand, foot, and ankle. Neural Prolotherapy has also been shown effective with chronic pain due to in-growth of nerve endings in scar tissue following certain surgical procedures.

Clinical conditions that may benefit from Neural Prolotherapy or Perineural injection therapy

• Patients with chronic Neck and Back pain
• Injuries to the shoulder, rotator cuff injuries & frozen shoulder
• Temporomandibular joint (TMJ) dysfunction
• Knee Pain
• Ankle impingement syndrome
• Tennis elbow
• Golfers elbow 
• Carpal Tunnel Syndrome (CTS)
• Iliotibial band syndrome
• Buttock pain due to cluneal nerve entrapment or piriformis syndrome
• Patients struggling with limited mobility and experiencing joint pain

References:

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