Neural prolotherapy or neurofascial prolotherapy (NPT) was established as a treatment for chronic joint pain in the US during the 1990s, and is not to be confused with neural therapy as developed in Germany. In contrast with the latter, which uses procaine as a local anaesthetic to counter pain and scars, NPT is a form of regenerative treatment for connective tissue and nerves. NPT involves administering dextrose at low concentrations to nerves, or at higher concentrations to connective tissues. The treatment targets small nerves and the painful reaction to inflammation they cause (neurogenic inflammation).
Ligaments, tendons, and joints have TRPV1-sensitive group C fibres (pain nerve fibres) that cause a deep pain sensation when activated. This pain often spreads from the source of pain to the rest of the body, making it difficult for the patient to say where it hurts; the pain is more of a deep, diffuse, and mostly somewhat burning ache. The nerves themselves carry nerves, nervi nervorum, which release substance P (SP) and calcitonin gene-related peptide (CGRP) when activated to group C nerve fibres, causing the perception of pain and swelling in the nerves and surrounding tissues.
John Lyftogt (New Zealand) reported on the effects of dextrose application in work on neural prolotherapy as follows: Cutaneous nerves pass through many fascial layers on their way to the spine, where they may become compressed and inflamed; this causes chronic constriction injury, or CCI. The nerve in the inflamed and compressed tissue is no longer able to follow a movement without mechanical irritation, causing neurogenic inflammation pain.
Injecting a sugar solution adapted for the body to the nerves permanently relieves chronic pain by reducing nerve and tissue swelling. NPT has successfully been used in the treatment of joint pain such as in osteoarthritis as well as pain in ligaments, tendons, or muscles (muscle pain during movement, cramp sensation), and has come to play an essential role in complex treatment concepts in regenerative medicine together with laser and PRP therapy. Again, the principle behind regenerative medicine applies – signalling one of the body’s own regeneration processes towards a well-tolerated, low-risk, and long-acting outcome with the aim of using the body’s own healing processes.