Hyaluronidase is an enzyme that plays a crucial role in breaking down hyaluronic acid, a substance found in excessive amounts in fibrous tissue. Hyaluronic acid contributes to the stiffness and density of the fibroma. By administering hyaluronidase into the fibroma, the enzyme helps to break down and disperse the hyaluronic acid, allowing the fibrous tissue to become more pliable and reducing its overall density. This can lead to a reduction in the size of the fibroma.
Hyaluronidase acts by breaking down the connections between the long chains of hyaluronic acid, which loosens the structure of the fibrous tissue. This breakdown of hyaluronic acid also promotes better dispersion of other injected substances, such as the steroid and local anaesthetic, into the fibroma. The increased dispersion enhances the therapeutic effect of the treatment.
Verapamil gel is a topical medication that has been used as a treatment for plantar fibroma. Plantar fibroma is a benign tumour that typically arises on the bottom surface of the foot and can cause discomfort and pain while walking or standing. Verapamil gel is thought to work by reducing the activity of fibroblast cells that are responsible for the formation of the fibrous tissue that makes up the tumour.
This procedure involves heating the nerve to about 40 degrees Centigrade. At this temperature the nerve is not destroyed or damaged. There is however some evidence that nerve function is affected in such a way as to reduce pain. The exact mechanism is not fully understood but there are a number of studies which show that patients may obtain benefit. In particular, pulsed radiofrequency has been shown to help with heel pain. Mr McCulloch has noted positive responses from patients suffering from various forms of nerve pain including peripheral neuropathy.
The procedure involves placing a fine radiofrequency needle next to the effected nerve under ultrasound guidance. A small amount of local anaesthetic is used. Recovery is generally rapid and unremarkable and patients can remain active. Because local anaesthesia is used the patient should not drive home and appropriate transport should be arranged.
Because pulsed radiofrequency is a non-ablative (non-destructive) procedure, the risk of complication is very small. The main risk from the procedure is infection, but this remains unlikely. The needle itself may cause some short-term tenderness.
As the name implies, ablative radiofrequency heats a nerve to the extent that nerve tissue is destroyed. For this reason, unlike pulsed radiofrequency, it cannot be used on larger essential nerves. The London Podiatry Centre predominantly uses ablative radiofrequency for the treatment of Morton’s neuroma but also for other conditions where the patient would benefit from ablation of a small nerve. The procedure is often considered for those patients who have failed to respond to cryosurgery. The complication risk is potentially slightly higher than cryosurgery but remains lower than open surgery and offers patients a further treatment approach prior to moving on to possible open surgery.
Ablative radiofrequency has been used for a number of years to treat a range of medical conditions. It has been used in the treatment of arrhythmia (irregular heartbeat) and here the procedure is again used to destroy nerve tissue. Radiofrequency has also been used extensively to treat low back pain. The technique of radiofrequency for Morton’s neuroma is similar to cryosurgery as it is also undertaken under local anaesthetic and again, involves the introduction of a very fine probe / needle adjacent to the nerve. However, instead of exposing the nerve to extreme cold, heat is instead used to destroy the nerve. Recovery can take a little longer than cryosurgery and the procedure can involve slightly more post-operative pain than cryosurgery, although this is generally very manageable.
One key difference between radiofrequency and cryosurgery is the increased likelihood that the patient will become aware of long-term numbness at the base of the toes which have been treated. Cryosurgery rarely causes long term loss of sensation because of the nerves ability to recover following the procedure. In the case of radiofrequency, the nerve is effectively burned, and regeneration may not occur. Whilst some patients are conscious of a slight loss of sensation following radiofrequency, it is rarely a cause for concern and most patients tolerate this very well.
The London Podiatry Centre offers a range of specialist injections, please call the clinic for further information.