Marc Darrow MD,JD

The American Orthopaedic Foot and Ankle Society describes Morton’s Neuroma as feeling like you are “walking on a marble,” and you have persistent pain in the ball of your foot. A neuroma is a benign tumor of a nerve. Morton’s neuroma is not actually a tumor, but a thickening of the tissue that surrounds the digital nerve leading to the toes.

Many patients come into the office having been misdiagnosed with Morton’s neuroma. This condition affects the toe area, and is caused by nerves getting entangled at the base of the foot or in between the toes. Most often the problems associated with Morton’s neuroma are actually symptoms of metatarsalgia, which is a simple inflammation of the same area. Metatarsalgia has also been very successfully treated with PRP foot injections.

The foot is like all the joints in the body. When the ligaments that hold bone to bone are loose or lax, the bones of the foot, not bound in place by the foot ligaments, will float around. When the bones of the foot get too close together, they pinch everything between them including the nerves.

The people we see at our office typically are not newly diagnosed with Morton’s Neuroma. They have been suffering from foot pain for some time, had scans and x-rays. They were told to avoid walking barefoot, prescribed medication as needed, offered physical therapy along with shoe inserts and possibly a walking boot. Eventually they may have been offered a cortisone injection which may have worked short-term but clearly not long-term.

The many diagnosis of Morton’s neuroma and their controversies

An August 2021 update (1) to the medical publication STAT PEARLS describes Morton’s neuroma in this way: “Morton’s neuroma is a compressive neuropathy of the forefoot interdigital nerve. Neuropathy is chiefly due to compression and irritation at the plantar aspect of the transverse intermetatarsal ligament. It is not a true neuroma as the condition is degenerative rather than neoplastic (abnormal tissue growth). It is also referred to as Morton metatarsalgia, interdigital neuritis, Morton entrapment, interdigital neuralgia, interdigital neuroma, interdigital nerve compression syndrome, and intermetatarsal neuroma. The most common location for Morton neuroma is between the 2nd and 3rd metatarsals.”

A March 2021 paper (2) offers this second opinion: “Morton’s neuroma is a commonly encountered cause of forefoot pain, which may limit weight-bearing activities and footwear choices. Although the etiology and pathomechanism of this condition is controversial, the histological endpoint (where the patient ends up) is well established as benign perineural fibrosis (scaring, swelling or abnormality of the nerve) of a common plantar digital nerve, typically within the third intermetatarsal space. The diagnosis of Morton’s neuroma is mainly based on characteristic symptoms and clinical findings, but may be confirmed by ultrasonography. Although ultrasound is a highly accurate diagnostic tool for Morton’s neuroma, it is subject to interoperator variability due to differences in technique and level of experience.”

The many different treatments of Morton’s Neuroma

A June 2021 paper in the Journal of ultrasonography (3) describes initial treatments many patients may anticipate in treating their foot pain: “The management of Morton’s neuroma starts with conservative measures, usually with limited efficacy, including orthotics and anti-inflammatory medication. When conservative treatment fails, a series of minimally invasive ultrasound-guided procedures can be employed as second-line treatments prior to surgery. Such procedures include infiltration of the area with a corticosteroid and local anesthetic, chemical neurolysis with alcohol or radiofrequency thermal neurolysis.”

This paper further describes that a doctor using ultrasound guidance, to see where the injection is going, will have greater success with cortisone injection, chemical neurolysis and radiofrequency thermal neurolysis.

When cortisone does not work, what’s next?

A paper in the journal Foot and ankle surgery (4) looked at the factors that would make a patient a more successful candidate for cortisone and those factors that would help them predict which patients would require more treatments after a cortisone injection. The factors that influenced need for more treatment was a) younger, more active patients b) people who had larger neuromas.

The results of this paper revealed that of the 54 patients in this study, 51% required further treatment within 2 years (11 repeat cortisone injections, 18 patients moved onto surgery).

Short-term relief with cortisone. Possible side-effects

A June 2021 study (5) suggested that while corticosteroid injections offered some relief to patients with Morton’s neuroma, this paper reported 140 patients out of 469 study patients (29.85%) eventually underwent surgery after corticosteroid injections due to returning pain.

What does ultrasound reveal about foot pain? In this study it reveals where a foot insole will help certain conditions including Morton’s Neuroma.

In this July 2021 paper (6) researchers wanted to determine if ultrasound imaging could demonstrate if a patient responded to treatment of their metatarsalgia with custom-made orthoses. Here is the study summary:

  • Twenty patients (15 females; average age: 62.6) affected by metatarsalgia in 27/40 feet (seven patients had metatarsalgia in both feet) underwent clinical evaluation before, three months and six months after treatment with custom-made full foot insole.
  • Ultrasound was performed before and three months after the use of orthoses to examine the presence of intermetatarsal/submetatarsal bursitis, metatarsophalangeal joints effusion, anterior plantar fat pad edema, flexor tendinitis/tenosynovitis, and Morton’s neuroma.
  • After 3 and 6 months of insoles use, patients showed showed a significant reduction in pain and disability.
  • Before treatment, ultrasound revealed 22 intermetatarsal bursitis, 16 submetatarsal bursitis, 10 joint effusions, 20 fat pad edema, 3 flexor tendinitis/tenosynovitis and 3 Morton’s neuromas.
  • After 3 months of treatment, a significant decrease of intermetatarsal bursitis was observed. No significant changes were observed in any other ultrasound parameters.

The shoe inserts helped some conditions, not all.

More on effectiveness or lack of effectiveness of shoe change

A May 2020 study (7) examined the effectiveness of recommending therapeutic footware for the Morton’s neuroma patient.

“The first approach in the early stages of this condition usually begins with shoe modifications and orthotics, designed to limit the nerve compression. In order to prevent or delay the development of Morton’s neuroma, shoes should be sufficiently long, comfortable, broad toe-boxed, should bear a flat heel and a sufficiently thick external sole which should not be excessively flexible.

Most authors suggested that an insole with medial arch support and a retrocapital (insole) bar or pad, just proximal to the metatarsal heads, displaces the pressure sites and can be beneficial to relieve the pain from the pinched nerve.

A threshold period of 4.5 months appears to emerge from the results of the analyzed studies, indicating that, beyond this period and in neuromas larger than 5-6 mm, orthotics and/or shoes modifications do not seem to give convincing results, proving to be more a palliation for the clinical condition to allow an acceptable life with pain rather than a real treatment.”

Failure after surgery – The failure rate following surgical excision has been reported as up to 30%

A May 2020 study (8) examined the failure rate of Morton’s Neuroma surgery:

“The failure rate following surgical excision has been reported as up to 30%. The main reasons for pain following surgical excision are: incorrect diagnosis, neuroma in adjacent intermetatarsal space, incomplete resection, complex regional pain syndrome or recurrence of the Morton’s neuroma also known as stump neuroma.

Use of steroid injection is the most commonly used modality for dealing with pain following surgical excision. The mechanism of action is breakdown of scar tissue and adhesions. Overall the chances of success following revision surgery are much less satisfactory than primary excision.”

Ask Dr. Darrow

I hope this article provided some answers for you and your search for foot pain help. Use the form below if you have further questions.

[wpforms id=”2153″]

References:

1 Munir U, Tafti D, Morgan S. Morton Neuroma. 2021 Aug 3. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 29262171.
2 Mak MS, Chowdhury R, Johnson R. Morton’s neuroma: review of anatomy, pathomechanism, and imaging. Clinical Radiology. 2020 Nov 7.
3 Klontzas ME, Koltsakis E, Kakkos GA, Karantanas AH. Ultrasound-guided treatment of Morton’s neuroma. Journal of Ultrasonography. 2021 Jun 7;21(85):e134.
4 Mahadevan D, Salmasi M, Whybra N, Nanda A, Gaba S, Mangwani J. What factors predict the need for further intervention following corticosteroid injection of Morton’s neuroma?. Foot and Ankle Surgery. 2016 Mar 1;22(1):9-11.
5 Choi JY, Lee HI, Hong WH, Suh JS, Hur JW. Corticosteroid injection for Morton’s interdigital neuroma: A systematic review. Clinics in orthopedic surgery. 2021 Jun;13(2):266.
6 Albano D, Bonifacini C, Zannoni S, Bernareggi S, Messina C, Galia M, Sconfienza LM. Plantar forefoot pain: ultrasound findings before and after treatment with custom-made foot orthoses. La radiologia medica. 2021 Jul;126(7):963-70.
7 Colò G, Rava A, Samaila EM, Palazzolo A, Talesa G, Schiraldi M, Magnan B, Ferracini R, Felli L. The effectiveness of shoe modifications and orthotics in the conservative treatment of Civinini-Morton syndrome: state of art. Acta Bio Medica: Atenei Parmensis. 2020;91(4-S):60.
8 Bhatia M, Thomson L. Morton’s neuroma–Current concepts review. Journal of clinical orthopaedics and trauma. 2020 May 1;11(3):406-9.

 

A leading provider of stem cell therapy, platelet rich plasma and prolotherapy
11645 WILSHIRE BOULEVARD SUITE 120, LOS ANGELES, CA 90025

PHONE: (800) 300-9300 or 310-231-7000

Stem cell and PRP injections for musculoskeletal conditions are not FDA approved. We do not treat disease. We do not offer IV treatments. There are no guarantees that this treatment will help you. Prior to our treatment, seek advice from your medical physician. Neither Dr. Darrow, nor any associate, offer medical advice from this transmission. This information is offered for educational purposes only. The transmission of this information does not create a physician-patient relationship between you and Dr. Darrow or any associate. We do not guarantee the accuracy, completeness, usefulness or adequacy of any resource, information, product, or process available from this transmission. We cannot be responsible for the receipt of your email since spam filters and servers often block their receipt. If you have a medical issue, please call our office. If you have a medical emergency, please call 911.

 

Scroll to Top