Jeremy Lefort is one of the most experienced podiatrists in Melbourne having been practising traditional Prolotherapy since 2007.
In 2010, Jeremy attended the inaugural 3-day Perineural Injection (Neural Prolotherapy) Workshop held by Dr John Lyftogt (Founder of Neural Prolotherapy) in Christchurch, New Zealand.
Injection to repair connective tissue (ligament, tendon and cartilage)
Subcutaneous Perineural Injection (SPNI): Injection close to subcutaneous (under the skin) nerves using a low concentration of Dextrose to restore their normal function.
Deep Perneural Injection (DPNI): The principle of using a low concentration of dextrose is the same as for SPNI however with DPNI a larger volume is injected into a deeper region where the nerve may be getting trapped or constricted as it passes through fascial layers or tunnels. The fluid creates a stretch on the tissue layers increasing the space and reducing constriction on the nerve. This technique is called hydrodissection.
What is Prolotherapy?
Prolotherapy is an injection technique whose primary intent is to repair connective tissue (predominantly tendons and ligaments). The term Proli is Latin for “to grow.”
What is Prolotherapy used for?
Plantar Fasciitis (Heel pain) and Achilles tendon pain are the two most common problems that our Podiatrists treat with Prolotherapy. However, any ligament or tendon involving the foot or ankle can respond to prolotherapy.
How Does Prolotherapy Work?
Dextrose injection (12.5% to 25% concentration) stimulates a brief AA (arachidonic acid) pathway inflammation. AA inflammation is the type of inflammation to which most doctors are referring when they use that word. After an injury, the body uses primarily AA inflammation to try to repair the damage. With prolotherapy there is no significant damage, because there is no stretching or tearing of fibres, but the body still begins a repair process, which allows the structure to become stronger and tighter rather than first becoming weaker and looser.
How many injections are required?
On average, most patients require 3-5 injections usually repeated every 2-3 weeks, however, as everyone responds differently to the dextrose injections this can be quite variable.
How long does it take to work?
Ligaments and tendons generally take approximately 3 months from the commencement of an inflammatory response to repair and remodel.
What can I expect after the Injection?
Immediately following the injection the area will feel numb due to the fact that the Dextrose injection also contains some local anaesthetic. When the anaesthetic wears off there is likely to be some pain in the area for 2-3 days resulting from the intended inflammation created by the injection. Although painful, this is viewed as a positive response because it indicates the initiation of a new healing cycle. If the pain is enough so consider taking pain killers, anti-inflammatory medications such as Nurofen and Voltaren should be avoided. Otherwise, patients can continue on with daily activities as normal, except for limitations related to the presenting complaint as advised by your Podiatrist.
What are Perineural Injections used for?
Many conditions affecting the foot and ankle may respond to perineural injections. Two of the more common conditions we treat at this clinic are Intermetetarsal Bursitis and Morton’s neuroma.
Often pain presents as generalised, such as over the top of the foot. In these situations it is common to find multiple issues including muscle tightness with resultant nerve irritation and an underlying contributing foot posture. Perineural injections can be particularly useful as an adjunctive treatment in these circumstances where failing to treat the nerve will result in failure to completely resolve pain.
How it Works
The body has a vast network of nerves (termed the peptidergic sensory system) with receptors sitting on their surfaces that, when stimulated, have the ability to produce either healthy non-pain producing proteins or damaging pain-producing proteins. If these nerves are over-stimulated and “up-regulated” the production of pain producing proteins, eg. Substance P, and damaging proteins, eg. CGRP-1, increases with resultant pain and tissue breakdown. This is termed “neuropathic Inflammation”.
Dextrose injection in low concentration (5%) has been clinically observed to rapidly block the receptors on the surfaces of these nerves, thus “down–regulating”, and helping to restore normal nerve function. This generally needs to be repeated but after several treatments leads to progressive benefit. This does not stimulate AA inflammation to grow new tissue as we are treating nerves not tendons or ligaments. That is why, although related, we do not refer to this as “prolotherapy”.
How are these nerves damaged?
The small sensory nerves of the peptidergic system pass from the skin to deeper structures penetrating though small openings in the fascia surrounding muscles and other compartments within the lower leg and foot.
Simply surrounding a nerve around its entire circumference, even without squeezing it, will cause it to behave abnormally. Touching a nerve on all sides can lead to a swelling reaction where the area becomes a point of constriction and the nerve swells on either side of the constriction.
Nerves are not only irritated when they have to penetrate fascia at the skin level, but also when they have to penetrate layers of fascia in other regions.
Nerves must also make their way around muscles, often turning 180 degrees or more. Nerves in the leg have to work their way through lower leg muscles so tight lower leg muscles may result in constriction as the nerve passes through narrowed openings in the fascia.
Nerves also have to contend with bones and various “tunnels”, or passages. Any of these areas can be changed in such a way as to irritate the nerve.
An example is the nerve passing through the Tarsal Tunnel in the foot (similar to the Carpal Tunnel in the hand) and the nerve passing through the long bones in the foot called the intermetatarsal space (area associated with Morton’s neuroma).
How is the injection performed?
SPNI is done using a fine needle inserted along the path of the involved nerve and a small volume of fluid is injected just underneath the skin.
DPNI differs in that a larger volume is injected into the area. Once the location of nerve constriction or entrapment is identified the needle is placed through the fascia, and fluid is injected to stretch the space.
What can I expect after treatment?
As we are not aiming to induce an inflammatory effect with Perineural injections, there is an absence of post injection discomfort that occurs with Prolotherapy.
SPNI may cause a slight very short (minutes) lived stinging sensation at the site of the injection, otherwise all you should feel is a reduction in the presenting complaint.
DPNI may have the additional feeling of fullness as larger volumes of fluid are injected, however this feeling reduces rapidly as the fluid disperses within the tissue.
Patients can continue on with daily activities as usual.