Second Line: Non-surgical Treatments for Persistent Morton’s neuroma
Ultrasound guided non-surgical procedures are the treatment of choice to cure Morton’s neuroma. If conservative treatment and corticosteroid injections are not effective in treating your Morton’s neuroma, then more invasive treatment is warranted. Depending on your other medical conditions and physician consultation we perform:
- Ultrasound guided radiofrequency ablation,
- Ultrasound guided cryotherapy ablation,
- Ultrasound guided neurolytic injection,
- Ultrasound guided platelet rich plasma injection, and,
- Ultrasound guided Stem Cell Therapy.
If done by a specialist physician who is experienced in doing these procedures under ultrasound guidance the three first procedures should be equally as effective, with success rates above 85%. To read the medical studies that show the effectiveness of these procedures for the treatment of Morton’s neuroma click here.
We use ultrasound guidance for for all our procedures and this allows us to visualize the needle tip when administering the treatment, confirming proper needle placement. Seeing the needle tip results in a higher degree of success and the prevention of injury to other local tissues. Furthermore, the use of ultrasound can help in the diagnosis of other local pathology, e.g. synovitis, bursitis or tendon pathology. Frequently, we also use a nerve stimulator to ensure even greater accuracy in placement of the needle or probe.
1. Radiofrequency Ablation
Ultrasound guided radiofrequency ablation is a sophisticated, minimally invasive procedure that is associated with high patient satisfaction scores and long term pain relief for Morton’s neuroma. It is a procedure that uses high frequency radio waves to heat the sensory nerve that is affected in Morton’s neuroma to 90 degrees Celsius. At this temperature the heat breaks down proteins preventing the nerve fibers from transmitting pain. The nerve is destroyed and the pain from that area is not transmitted any further. In addition, radiofrequency ablation may cause the creation of new blood vessels speeding up the healing process.
Radiofrequency ablation has been used in medicine for many years, particularly in the case of abnormal heart rhythms and back pain. The use in Morton’s neuroma is a relatively recent development. The procedure is minimally invasive and at our center these procedures are performed under local anesthetic with ultrasound and nerve stimulator guidance to ensure correct positioning.
It is a mostly painless procedure and you are likely to only feel pain when the local anesthetic is injected into the foot. On the day of the procedure, the area is anesthetized with local anesthetic. After it has taken effect, a very small puncture is made over the painful area. The radiofrequency needle is introduced and an ultrasound is used to guide the positioning of the needle. The position of the needle is then rechecked and refined using a nerve stimulator.
Once the needle is in the correct position, an electrode is placed through the needle and the tip of the electrode is heated to about 90 degrees Celsius for 90 seconds and repeated according to protocol. The site is covered with a bandage and patient is advised to reduce activity, ice and elevate the foot. The bandage can be removed the following day and patient can cover the area with a regular Band-Aid. You should keep the injection site clean and dry for at least 24 hours. Reduced activity can be resumed within one or two days of the procedure and any pain that occurs is usually managed with an NSAID or Tylenol. High impact activities on the ball of the foot should be avoided for a week or so. You can drive home on the day of the procedure.
Side effects are not generally seen with this procedure, but a few are a possibility. Infections are rare, as is abscess formation at the puncture site. You may develop bruising that can be painful. Numbness or a lack of feeling in around the incision area can also happen, but this side effect is rare.
You may experience relief from this procedure within a week, but often it takes a longer period of time to heal completely. If there is still pain at seven weeks, the procedure can be performed again.
Most patients find that after two ultrasound guided radiofrequency ablations their pain has decreased significantly. If, in the very rare case, ultrasound guided radiofrequency ablation has little effect it may be time to look at a different ultrasound guided ablation procedure.
To see a video of Dr. Pearl doing an ultrasound guided radiofrequency ablation of a Morton’s neuroma, click here. To read the medical studies that show the effectiveness of radiofrequency ablation for Morton’s neuroma click here.
Ultrasound guided cryosurgery (also known as cryoablation) is similar to radiofrequency ablation in that it causes carefully targeted injury to destroy nerves to interrupt the pain. While radiofrequency ablation uses radio waves to create heat and break down nerves, cryosurgery uses cold/ice instead, using medical-grade nitrous oxide to generate extremely cold temperature to selectively destroy neuroma tissue. It has been used for many years to relieve the pain of various nerve pathologies, including Morton’s neuroma.We use ultrasound and nerve stimulator guidance to increase the effectiveness of this treatment by ensuring the correct placement of the probe tip. Frequently, the position of the needle is then rechecked and refined using a nerve stimulator.
It is a mostly painless procedure and you are likely to only feel pain when the local anesthetic is injected into the foot. On the day of the procedure, the area is anesthetized with local anesthetic. After this has taken effect, a very small incision is made over the painful area. The cryoprobe is introduced and an ultrasound is used to guide the positioning of the probe. Once in the correct position, freezing is initiated for a period of 2-3 minutes. The procedure is repeated from 2 to 4 times depending on each individual case.
The site is covered with compression bandage and patient is advised to reduce activity, ice and elevate for the remainder of the day. The bandage can be removed the following day and patient can cover the area with a regular Band-Aid.
You should keep the injection site clean and dry for at least 24 hours. Normal activity can be resumed within one or two days of the procedure and any pain that occurs is managed with a NSAID or Tylenol. Pain continues to reduce over a two-week period; if at the end of a four-week period the reduction is not sufficient, the procedure can be repeated.
The cyroprobe used in cryotherapy creates a 6-8mm ice ball at its tip that reaches temperatures of -70 degrees Celsius, which freezes the Morton’s neuroma, prevents nerve transmission and decreases pain. This ball of ice degenerates the outer sheath of the nerve (demyelinazation) and destroys part of the nerve (Wallerian-like degeneration). The ice ball destroys about one cm of the nerve, which regenerates back at between one to three millimeters per day; therefore the axon or nerve regeneration should be complete within several weeks. It appears long lasting pain relief is due to the reduction of both nerve swelling and nerve sheath scarring.
The majority of Morton’s neuroma patients obtain significant or complete pain relief immediately following the procedure. In the past, the cryoablation was blindly applied to the area, but recent advances in ultrasound technology together with the use of a nerve stimulator have allowed for careful placement of the probe and therefore better results. Pain relief is more complete and decreases the need for further procedures.
Cryoablation (or cryosurgery) differs from radiofrequency ablation in that the pain relief from cryoablation can be a little sooner than radio frequency which can sometimes take up to two months to demonstrate effective pain control. The use of cold also decreases the risk of a further neuroma that can sometimes occur after surgical intervention. When very little or no pain relief occurs, it is frequently because of dense scar tissue related to previous Morton’s neuroma treatments in the foot. In these cases inserting the cryoprobe through the underside (plantar) aspect of the foot can often overcome this problem.
However in some cases, cryosurgery can also take up to 2 months for full pain relief to be achieved. Side effects are rare with this procedure and may include bruising, infection or frostbite at the area of insertion. You may also feel a small lump in your foot where the procedure was performed. This generally goes away within 3 to 6 months and does not cause pain.
Virtually all Morton’s neuroma patients who have had cryoablation or cryosurgery for Morton’s neuroma have maintained full motor function with no greater loss of sensation then they had prior to the procedure. If patients are unlucky enough to experience a return of Morton’s neuroma symptoms the cryoablation procedure can simply be repeated or other non-surgical treatments can be performed.
Most patients find that after two cryoablation their pain has decreased significantly. If, in the very rare case, ultrasound guided cryoablation has little effect it may be time to look at a different ultrasound guided ablation procedure.
Cryoablation (or cryosurgery) involves very cold temperatures, therefore this procedure is not offered to those Morton’s neuroma patients with poor circulation or peripheral vascular disease or conditions such as Raynaud’s Phenomena.
You should keep the injection site clean and dry for at least 24 hours. Reduced activity can be resumed within one or two days of the procedure and any pain that occurs is usually managed with an NSAID or Tylenol. High impact activities on the ball of the foot should be avoided for a week or so. You can drive home on the day of the procedure.
To read the medical studies that show the effectiveness of cryoablation for Morton’s neuroma click here.
3. Neurolytic Injections
Neurolytic injections inject a mixture of a sclerosing agent (usually concentrated alcohol) and local anesthetic directly into the Morton’s neuroma in order to eliminate or significantly diminish the ability of the nerve to transmit pain signals, thereby reducing pain sensation.
An experienced practitioner should do the procedure under ultrasound guidance. The use of an ultrasound and a nerve stimulator to guide needle placement is especially important when using high concentrations of sclerosing agents to ensure that the sclerosing agent does not leak from the immediate area surrounding the Morton’s neuroma. If a leak occurs, the sclerosing agent can damage the surrounding structures.
The affected area is anesthetized with local anesthetic. Once this has taken effect, a mixture of the sclerosing agent and local anesthetic is injected to the Morton’s neuroma using ultrasound and nerve stimulator guidance to ensure proper needle placement. The procedure is minimally invasive and at our center, is performed by one of our specialists who specialize in these types of ultrasound-guided procedures.
After the procedure, the injection site is covered with a small Band-Aid for protection. Patients wait 15 -30 minutes following the injection, and then they can carefully move around the office. The majority of Morton’s neuroma patients obtain significant or complete pain relief immediately following the procedure. Patients to return to normal activities the following day. With this type of injection, follow up appointments are vital. If significant pain relief is achieved but pain still persists, the procedure can be repeated after a 5-10 day interval. Additional injections, although rarely required, may be administered if symptoms persist.
When done by experienced practitioners, this procedure has few side effects but in rare cases, they can occur. First, non-target tissue is at risk for being damaged by the sclerosing agent resulting in the sloughing off of skin or possibly a non-healing wound. Second, the neuroma may grow back and cause the initial pain that prompted the procedure, but this occurs years later. Finally, numbness and tingling in the toes may be noted if other portions of the nerve become damaged.
Most patients find that after two ultrasound guided neurolytic injections their pain has decreased significantly. If, in the very rare case, the ultrasound guided neurolytic injection has little effect it may be time to look at a different ultrasound guided ablation procedures.
To read the medical studies that show the effectiveness of neurolytic injections for Morton’s neuroma click here.
4. Platelet Rich Plasma Injections
Platelet rich plasma (PRP) treatment is the injection of the patient’s own platelets to treat Morton’s neuroma. It is used for various musculoskeletal problems, such as of injured tendons, ligaments, muscles, joints. Platelet activation plays a key role in the process of wound and soft tissue healing, especially when inflammation is present. Platelet rich plasma injections involves the use of a portion of the patient’s own blood, which has a high platelet concentration. PRP injections are prepared by using a small amount of the patient’s own blood which is centrifuged and then a portion of concentrated blood containing activated platelets is injected into the abnormal tissue.
This causes a local inflammatory reaction, releasing growth factors that stimulate healing and muscle regeneration, and limit the amount of scar tissue. Ultrasound imaging is used to guide the injection and this increases the accuracy of the PRP procedure, and potentially reduces post-procedural pain. PRP injection therapy is generally completed in just one session, but may require additional injections depending upon the clinical circumstances.
How Do We Use PRP Injections in Morton’s neuroma?
We use PRP injections sparingly in certain patients with Morton’s neuroma, generally in those patients who have indications of a co-exisiting bursitis or patients who have had Morton’s neuroma surgery and have considerable post surgical scarring where PRP can be very effective. Additionally PRP is also effective in treating Plantar Fasciitis.
A PRP injection can be uncomfortable and cause post-procedural pain that lasts a few days. When used to treat Morton’s neuroma, PRP injections should always be combined with other treatments. Some rest is needed immediately following the procedure. We insist on seeing any out of town Morton’s neuroma patients receiving a RPR injection 3 days after the injection, so if you have your injection on Friday, we will see you for a follow up visit on Monday.
PRP Injection Side Effects:
Most patients will experience some post-procedural pain at the injection site for up to 3 days and in some cases longer. This is typically managed with ice and over-the-counter pain relievers like Acetaminophen (Tylenol); however the physician may prescribe stronger pain relievers. Non-steroidal anti-inflammatory agents (NSAIDS) should be avoided since they interfere with the effectiveness of the PRP treatment.
Other side effects of PRP injections are very limited as the patient is utilizing their own blood, which they should have no reaction to. Sometimes the color around the skin of a PRP injection will appear bruised. Rare complications included infection at the injection site and bleeding especially with anticoagulant therapy or bleeding disorders. You should not have PRP if you have cancer or metastatic disease, an active infection or a low platelet count. You should also not have a PRP injection if you are pregnant or are breastfeeding.