Morton neuroma: comparative results of two conservative methods

Infiltrative Treatment of Morton's Neuroma: A Systematic Review

BACKGROUND

Morton's neuroma (MN) is one of the most frequent neurological pathologies in feet, affecting approximately 4% of the general population. The treatment of MN can be surgical, conservative, and infiltrative, with different substances used in the injections for MN, as steroids, sclerosing solutions, and others. This review aims to evaluate the efficacy of current infiltrative therapy for Morton's neuroma and, additionally, to define adverse effects of this therapy.

MATERIAL AND METHODS

A literature search was performed in PubMed, Embase, CINHAL, Epistemonikos, Web of Science (WOS), SPORTSDiscus and Cochrane Library. This search involved the application of all types of infiltrative treatment applicable to MN. The search was limited to original data describing clinical outcomes and pain using the Visual Analogue pain Scale (VAS) or the Johnson Satisfaction Scale, between February and June 2023.

RESULTS

Twelve manuscripts were selected (six randomized controlled trials and six longitudinal observational studies) involving 1,438 patients. Capsaicin was reported to produce a VAS score reduction of 51.8%. Corticosteroids also reported a high level of efficacy. Alcohol and Hyaluronic Acid injections are well tolerated, but the effects of their application need further research. There were no serious adverse events.

CONCLUSIONS

Corticosteroids, sclerosant injections, hyaluronic acid and capsaicin have been shown to be effective in reducing the pain related to MN.

Treatments for Morton's neuroma

BACKGROUND

Morton's neuroma (MN) is a painful neuropathy resulting from a benign enlargement of the common plantar digital nerve that occurs commonly in the third webspace and, less often, in the second webspace of the foot. Symptoms include burning or shooting pain in the webspace that extends to the toes, or the sensation of walking on a pebble. These impact on weight-bearing activities and quality of life.

OBJECTIVES

To assess the benefits and harms of interventions for MN.

SEARCH METHODS

On 11 July 2022, we searched CENTRAL, CINAHL Plus EBSCOhost, ClinicalTrials.gov, Cochrane Neuromuscular Specialised Register, Embase Ovid, MEDLINE Ovid, and WHO ICTRP. We checked the bibliographies of identified randomised trials and systematic reviews and contacted trial authors as needed.

SELECTION CRITERIA

We included all randomised, parallel-group trials (RCTs) of any intervention compared with placebo, control, or another intervention for MN. We included trials where allocation occurred at the level of the individual or the foot (clustered data). We included trials that confirmed MN through symptoms, a clinical test, and an ultrasound scan (USS) or magnetic resonance imaging (MRI).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We assessed bias using Cochrane's risk of bias 2 tool (RoB 2) and assessed the certainty of the evidence using the GRADE framework.

MAIN RESULTS

We included six RCTs involving 373 participants with MN. We judged risk of bias as having 'some concerns' across most outcomes. No studies had a low risk of bias across all domains. Post-intervention time points reported were: three months to less than 12 months from baseline (nonsurgical outcomes), and 12 months or longer from baseline (surgical outcomes). The primary outcome was pain, and secondary outcomes were function, satisfaction or health-related quality of life (HRQoL), and adverse events (AE). Nonsurgical treatments Corticosteroid and local anaesthetic injection (CS+LA) versus local anaesthetic injection (LA) Two RCTs compared CS+LA versus LA. At three to six months: • CS+LA may result in little to no difference in pain (mean difference (MD) -6.31 mm, 95% confidence interval (CI) -14.23 to 1.61; P = 0.12, I2 = 0%; 2 studies, 157 participants; low-certainty evidence). (Assessed via a pain visual analogue scale (VAS; 0 to 100 mm); a lower score indicated less pain.) • CS+LA may result in little to no difference in function when compared with LA (standardised mean difference (SMD) -0.30, 95% CI -0.61 to 0.02; P = 0.06, I2 = 0%; 2 studies, 157 participants; low-certainty evidence). (Function was measured using: the American Orthopaedic Foot and Ankle Society Lesser Toe Metatarsophalangeal-lnterphalangeal Scale (AOFAS; 0 to 100 points) - we transformed the scale so that a lower score indicated improved function - and the Manchester Foot Pain and Disability Schedule (MFPDS; 0 to 100 points), where a lower score indicated improved function.) • CS+LA probably results in little to no difference in HRQoL when compared to LA (MD 0.07, 95% CI -0.03 to 0.17; P = 0.19; 1 study, 122 participants; moderate-certainty evidence), and CS+LA may not increase satisfaction (risk ratio (RR) 1.08, 95% CI 0.63 to 1.85; P = 0.78; 1 study, 35 participants; low-certainty evidence). (Assessed using the EuroQol five dimension instrument (EQ-5D; 0-1 point); a higher score indicated improved HRQoL.) • The evidence is very uncertain about the effects of CS+LA on AE when compared with LA (RR 9.84, 95% CI 1.28 to 75.56; P = 0.03, I2 = 0%; 2 studies, 157 participants; very low-certainty evidence). Adverse events for CS+LA included mild skin atrophy (3.9%), hypopigmentation of the skin (3.9%) and plantar fat pad atrophy (2.6%); no adverse events were observed with LA. Ultrasound-guided (UG) CS+LA versus non-ultrasound-guided (NUG) CS+LA Two RCTs compared UG CS+LA versus NUG CS+LA. At six months: • UG CS+LA probably reduces pain when compared with NUG CS+LA (MD -15.01 mm, 95% CI -27.88 to -2.14; P = 0.02, I2 = 0%; 2 studies, 116 feet; moderate-certainty evidence). (Assessed with a pain VAS.) • UG CS+LA probably increases function when compared with NUG CS+LA (SMD -0.47, 95% CI -0.84 to -0.10; P = 0.01, I2 = 0%; 2 studies, 116 feet; moderate-certainty evidence). We do not know of any established minimum clinical important difference (MCID) for the scales that assessed function, specifically, the MFPDS and the Manchester-Oxford Foot Questionnaire (MOXFQ; 0 to 100 points; a lower score indicated improved function.) • UG CS+LA may increase satisfaction compared with NUG CS+LA (risk ratio (RR) 1.71, 95% CI 1.19 to 2.44; P = 0.003, I2 = 15%; 2 studies, 114 feet; low-certainty evidence). • HRQoL was not measured. • UG CS+LA may result in little to no difference in AE when compared with NUG CS+LA (RR 0.42, 95% CI 0.12 to 1.39; P = 0.15, I2 = 0%; 2 studies, 116 feet; low-certainty evidence). AE included depigmentation or fat atrophy for UG CS+LA (4.9%) and NUG CS+LA (12.7%). Surgical treatments Plantar incision neurectomy (PN) versus dorsal incision neurectomy (DN) One study compared PN versus DN. At 34 months (mean; range 28 to 42 months), PN may result in little to no difference for satisfaction (RR 1.06, 95% CI 0.87 to 1.28; P = 0.58; 1 study, 73 participants; low-certainty evidence), or for AE (RR 0.95, 95% CI 0.32 to 2.85; P = 0.93; 1 study, 75 participants; low-certainty evidence) compared with DN. AE for PN included hypertrophic scaring (11.4%), foreign body reaction (2.9%); AE for DN included missed nerve (2.5%), artery resected (2.5%), wound infection (2.5%), postoperative dehiscence (2.5%), deep vein thrombosis (2.5%) and reoperation with plantar incision due to intolerable pain (5%). The data reported for pain and function were not suitable for analysis. HRQoL was not measured.

AUTHORS' CONCLUSIONS

Although there are many interventions for MN, few have been assessed in RCTs. There is low-certainty evidence that CS+LA may result in little to no difference in pain or function, and moderate-certainty evidence that UG CS+LA probably reduces pain and increases function for people with MN. Future trials should improve methodology to increase certainty of the evidence, and use optimal sample sizes to decrease imprecision.

Republication of "Uses of Braces and Orthotics for Conservative Management of Foot and Ankle Disorders"

Nonsurgical management is almost always considered the first-line treatment for the vast majority of foot and ankle pathologies. Foot orthoses, shoe modifications, and therapeutic footwear are considered essential tools for successful conservative management of different foot and ankle disorders. Orthopedic foot and ankle surgeons should have a meticulous understanding of the lower extremity biomechanics as well as the pathoanatomy and the sequelae of diseases affecting the foot and/or ankle. This is essential to the understanding of the desired effects of the different inserts, orthotics, shoe modifications, or braces that may be prescribed for these conditions. In this article, we will summarize the orthoses used for treatment of the most commonly encountered foot and ankle pathologies, with the exclusion of treatment for the diabetic foot because of the unique requirements of that disease process.

Complications of alcohol injections for Morton’s neuroma

Introduction

Morton’s neuroma (MN) is a neuropathic metatarsalgia that causes pain in the plantar aspect of the forefoot generally between the third and fourth metatarsal heads. Treatment can be nonoperative or surgical. Among nonoperative procedures, alcohol injections are still commonly used as considered simple, relatively safe and well-tolerated treatment. However, they present transient and minor complications.

Methods

Two hundred patients with a diagnosis of MN underwent ultrasound-guided injections with a 47.5% alcohol solution between 2013 and 2020. We reviewed the current literature to highlight the known complications of this treatment, comparing them to the complications developed by our patients.

Results

Three patients out of 200 patients, developed necrosis of skin and subcutaneous tissue not described in previous studies about MN.

Conclusions

Our study focuses attention on the complications subsequent to the alcohol injection therapy for MN. Patients and surgeons should be aware that in a small number of cases this therapy can be burdened by necrotic complications of the skin.

Interventional Imaging Techniques as Alternative to Surgery of the Foot and Ankle

A variety of foot and ankle pathologies can impair patient's daily activities, ultimately requiring surgical management. However, with improvements in image-guided intervention, the joints, soft tissues, and osseous structures may be accessible using various percutaneous techniques as a potential alternative therapeutic tool, avoiding the need for surgery with its associated risks and morbidity. This article discusses the potential range of image-guided interventional treatments. Injections, aspiration, biopsies, cryoablation, and radiofrequency ablation are described. Newer novel treatments are also covered. Finally, the common pathologies of Morton's neuroma, Achilles tendinopathy, and plantar fasciitis are addressed.

Isolated Intermetatarsal Ligament Release as Primary Operative Management for Morton's Neuroma: Short-term Results

BACKGROUND

Although the precise pathoetiology of Morton's neuroma remains unclear, chronic nerve entrapment from the overlying intermetatarsal ligament (IML) may play a role. Traditional operative management entails neuroma excision but risks unpredictable formation of stump neuroma.

MATERIALS AND METHODS

Medical records were examined for adult patients who failed at least 3 months of conservative treatment for symptomatic and recalcitrant Morton's neuroma and who then underwent isolated IML decompression without neuroma resection.

RESULTS

A total of 12 patients underwent isolated IML decompression for Morton's neuroma with an average follow-up of 13.5 months. Visual Analog Pain Scale averaged 6.4 ± 1.8 (4-9) preoperatively and decreased to an average of 2 ± 2.1 (0-7) at final follow-up (P = .002). All patients reported significant improvement.

CONCLUSION

Isolated IML release of chronically symptomatic Morton's neuroma shows promising short-term results regarding pain relief, with no demonstrated risk of recurrent neuroma formation, permanent numbness, or postoperative symptom exacerbation.

LEVEL OF EVIDENCE

Level IV: Case series.

Long-term comparison between blind and ultrasound-guided corticoid injections in Morton neuroma

OBJECTIVES

This work compares the effectiveness of blind versus ultrasound (US)-guided injections for Morton neuroma (MN) up to 3 years of follow-up.

METHODS

This is an evaluator-blinded randomised trial in which 33 patients with MN were injected by an experienced orthopaedic surgeon based on anatomical landmarks (blind injection, group 1) and 38 patients were injected by an experienced musculoskeletal radiologist under US guidance (group 2). Patients were assessed using the visual analogue scale and the Manchester Foot Pain and Disability index (MFPDI). Injections consisted of 1 ml of 2% mepivacaine and 40 mg triamcinolone acetonide in each web space with MN. Up to 4 injections were allowed during the first 3 months of follow-up. Follow-up was performed by phone calls and/or scheduled consultations at 15 days, 1 month, 45 days, 2 months, 3 months, 6 months and 1, 2 and 3 years. Statistical analysis was performed using unpaired Student's t tests.

RESULTS

No differences in age or clinical measures were found at presentation between group 1 (VAS, 8.5 ± 0.2; MFPDI, 40.9 ± 1.1) and group 2 (VAS, 8.4 ± 0.2; MFPDI, 39.8 ± 1.2). Improvement in VAS was superior in group 2 up to 3 years of follow-up (p < 0.05). Improvement in MFPDI was superior in group 2 from 45 days to 2 years of follow-up (p < 0.05). Satisfaction with the treatment was higher in group 2 (87%) versus group 1 (59.1%) at 3 years of follow-up.

CONCLUSION

Ultrasound-guided injections lead to a greater percentage of long-term improvement than blind injections in MN.

KEY POINTS

• Ultrasound-guided corticosteroid injections in Morton neuroma provide long-term pain relief in more than 75% of patients. • Ultrasound-guided injections in Morton neuroma led to greater long-term pain relief and less disability than blind injections up to 3 years of follow-up. • The presence of an ipsilateral neuroma is associated with worse long-term disability score.

The Management of Multiple Morton's Neuromas in the Same Foot: A Systematic Review

The optimal treatment strategy for the presentation of multiple Morton's neuromas in adjacent intermetatarsal spaces of the same foot is yet to be determined. We aimed to summarize and assess the efficacy of current treatment strategies. A systematic review, adhering to PRIMSA guidelines was performed. A computer base search was completed in PubMed, Embase, Cinahl, ISI Web of Science, Scopus and Emcare, for articles reporting the treatment of multiple neuromas in the same foot. The review is registered in the international prospective register of systematic reviews (CRD42020213631). A total of 253 articles were identified, with 7 articles being included in the review. The most common treatment strategy reported was simultaneous neuroma excision using a single incision, while 2 studies each describe simultaneous excision with 2 separate incisions and delayed excision respectively. There is no strong evidence favoring use of delayed excision or multiple incisions. Further high-quality research is required to make more definitive conclusions and future research should investigate other strategies such as non-operative treatment.

Ultrasound-guided Injection Treatments versus Surgical Neurectomy for Morton Neuroma: A Cost-effectiveness Analysis

Background: Morton neuroma is a common, painful disorder of the foot with multiple treatment options of varying cost and effectiveness. Objective: The aim of this study was to determine the most cost-effective treatment pathway for symptomatic Morton neuromas that have failed conservative management. Methods: An incremental cost-utility analysis was performed comparing a direct to surgical neurectomy strategy with three injection selective strategies in which one or more ultrasound-guided injection therapies was tried first prior to surgery for non-responders. The three injection selective strategies included: (1) steroid selective (2) alcohol selective, and (3) steroid/alcohol selective in which both steroid injections and alcohol sclerosing injections were trialed successively prior to surgical neurectomy. The direct to surgery approach was compared with the three different injection selective strategies, and with a no-treatment strategy, in a decision-analytic model for a hypothetical group of patients with symptomatic Morton neuromas that had failed conservative management. Model parameters including treatment costs, effectiveness, complication rates, and health utility states were estimated from the literature, reimbursement databases, and expert opinion. The outcome was cost per quality adjusted life year (QALY) with a time horizon of three years. A societal cost perspective was adopted with a willingness to pay threshold of $100,000 per QALY. Sensitivity analyses for key model parameters were performed. Results: For the base input values, the steroid/alcohol selective strategy was dominant and yielded an incremental cost-effectiveness ratio of $4401/QALY compared to no treatment. The probabilistic sensitivity analysis supported this strategy in 74% of 10,000 simulated trials. Results were robust with low sensitivity to most input parameters. However, when the probability of successful alcohol injection treatment dropped below 40%, the steroid selective strategy became most cost-effective. Conclusion: A trial of ultrasound-guided injection therapies for Morton neuroma is a cost-effective strategy compared to proceeding directly to surgical neurectomy. Clinical Impact: Ultrasound-guided injection therapies are indicated as a first line treatment for patients with symptomatic Morton neuromas that have failed conservative management.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VI, foot and ankle

Objectives

Clarity regarding accuracy and effectiveness for interventional procedures around the foot and ankle is lacking. Consequently, a board of 53 members of the Ultrasound and Interventional Subcommittees of the European Society of Musculoskeletal Radiology (ESSR) reviewed the published literature to evaluate the evidence on image-guided musculoskeletal interventional procedures around this anatomical region.

Methods

We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around foot and ankle in order to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper that was shared with all panel members for final approval.

Results

A list of 16 evidence-based statements on clinical indications for image-guided musculoskeletal interventional procedures in the foot and ankle were drafted after a literature review. The highest level of evidence was reported for four statements, all receiving 100% agreement.

Conclusion

According to this consensus, image-guided interventions should not be considered a first-level approach for treating Achilles tendinopathy, while ultrasonography guidance is strongly recommended to improve the efficacy of interventional procedures for plantar fasciitis and Morton’s neuroma, particularly using platelet-rich plasma and corticosteroids, respectively.

Key Points

• The expert panel of the ESSR listed 16 evidence-based statements on clinical indications of image-guided musculoskeletal interventional procedures in the foot and ankle.

• Strong consensus was obtained for all statements.

• The highest level of evidence was reached by four statements concerning the effectiveness of US-guided injections of corticosteroid for Morton’s neuroma and PRP for plantar fasciitis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08125-z.

Efficacy of a Single Corticosteroid Injection for Morton's Neuroma in Adults: A Systematic Review

BACKGROUND

Morton's neuroma is a common condition that routinely presents in podiatric practice. The aim of this study was to systematically synthesize the evidence relating to the effectiveness of a corticosteroid injection for Morton's neuroma.

METHODS

Studies with a publication date of 1960 or later were eligible, and searches were performed within the Turning Research Into Practice database; the Cochrane Central Register of Controlled Trials; the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register; MEDLINE (Ovid); PubMed; Embase; Cumulative Index to Nursing and Allied Health Literature; and the gray literature. Study selection criteria included randomized and nonrandomized controlled trials where a single corticosteroid injection for Morton's neuroma pain was investigated. The primary outcome was Morton's neuroma pain as measured by any standard validated pain scale.

RESULTS

Ten studies involving 695 participants were included. The quality of the studies was considered low and subject to bias. Of the included studies, five compared corticosteroid injection to usual care, one compared corticosteroid injection to local anesthetic alone, one compared ultrasound-guided to non-ultrasound-guided injections, three compared corticosteroid injections to surgery, one compared small to large neuromas, six assessed patient satisfaction, four measured adverse events, one studied return to work, and one examined failure of the corticosteroid injection to improve pain. Overall, these studies identified a moderate short- to medium-term benefit of corticosteroid injections on the primary outcome of pain and a low adverse event rate.

CONCLUSIONS

A single corticosteroid injection appears to have a beneficial short- to medium-term effect on Morton's neuroma pain. It appears superior to usual care, but its superiority to local anaesthetic alone is questionable, and it is inferior to surgical excision. A very low adverse event rate was noted throughout the studies, indicating the intervention is safe when used for Morton's neuroma. However, the quality of the evidence is low, and these findings may change with further research.

Effectiveness of corticosteroid injections in Civinini-Morton's Syndrome: A systematic review

BACKGROUND

The aim of this paper is to analyze the effectiveness of corticosteroid injections (CI), in combination with or without a local anaesthetic, for Civinini-Morton's Syndrome to determine which protocol could be the most appropriate among conservative treatments.

METHODS

All selected articles were screened using a thorough database search of PubMed, EMBASE and SCOPUS to assess their suitability to the research focus.

RESULTS

Selection produced 10 articles as full-text, for a total of 590 patients, with a mean follow-up of 14 ± 14.2 (range 3-48) months. Johnson satisfaction scale, resulting from 6 studies, scored 25.6% (range 5-38) and 39.4% (range 15-51.8), respectively completely satisfied and satisfied with minor reservations. Mean VAS, declared in 5 studies, decreased from 70.7 ± 16.5 (range 67-89) to 33.4 ± 7.6 (26-42.5) points (p < 0.01). Most common complication was skin depigmentation in 7 (2.6%) cases.

CONCLUSIONS

CI appear to be a safe treatment allowing good results with a very low complications rate. A neuroma of 6.3 mm seems to be the cut-off size; below which CI could have best indications and be considered as an intermediate treatment between shoe modifications and more invasive procedures such as percutaneous alcoholization or surgery.

LEVEL OF EVIDENCE

Level II, systematic review.

Corticosteroid Injection for Morton's Interdigital Neuroma: A Systematic Review

Backgroud

This review aimed to evaluate the effects of corticosteroid injections on Morton's neuroma using an algorithmic approach to assess the methodological quality of reported studies using a structured critical framework.

Methods

Several electronic databases were searched for articles published until April 2020 that evaluated the outcomes of corticosteroid injections in patients diagnosed with Morton's neuroma. Data search, extraction, analysis, and quality assessments were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). guidelines, and clinical outcomes were evaluated using various outcome measures.

Results

With 3–12 months of follow-up, corticosteroid injections provided satisfactory outcomes according to Johnson satisfaction scores except in two studies. Visual analog scale scores showed maximal pain reduction between 1 week and 3 months after injection. We found that 140 subjects out of 469 (29.85%) eventually underwent surgery after receiving corticosteroid injections due to persistent pain.

Conclusions

Corticosteroid injections showed a satisfactory clinical outcome in patients with Morton's interdigital neuroma although almost 30% of the included subjects eventually underwent operative treatment. Our recommendation for future research includes using more objective outcome parameters, such as foot and ankle outcome scores or foot and ankle ability measures. Moreover, studies on the safety and effectiveness of multiple injections at the same site are highly necessary.

Medium-Term Results of Corticosteroid Injections for Morton's Neuroma

BACKGROUND

The objective of this study was to evaluate the medium-term results of corticosteroid injections for Morton's neuroma.

METHODS

This was a prospective follow-up study of a previous randomized controlled trial (RCT). Forty-five neuromas in 36 patients were injected with a single corticosteroid injection either with or without ultrasound guidance. As the results of the RCT showed no difference in outcomes between techniques, the data were pooled for the purpose of this study. Questionnaires were sent out and responses were collected via mail or telephone interview. Results were available in 42 out of 45 neuromas. There was a sex split of 68% female/32% male with a mean age of 62.6 years (SD, 12 years).

RESULTS

At mean follow-up of 4.8 years (SD, 0.91 years), the original corticosteroid injection remained effective in 36% (n = 16) of the patients. In these cases, the visual analog scale (VAS) pain score (P < .001) and Manchester-Oxford Foot Questionnaire Index (MOxFQ Index) (P = .001) remained significantly better than preintervention scores. The remaining cases underwent either a further injection or surgery. Fifty-five percent of the 11 neuromas that received a second injection continued to be asymptomatic in the medium term. Overall, 44% (n = 20) of the initial cohort underwent surgical excision by the medium-term follow-up. The VAS score, MOxFQ Index, and satisfaction scale score across all groups were not significantly different.

CONCLUSION

Corticosteroid injections for Morton's neuroma remained effective in over a third of cases for up to almost 5 years. A positive outcome at 1 year following a corticosteroid injection was reasonably predictive of a prolonged effect from the injection.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Morton's neuroma: review of anatomy, pathomechanism, and imaging

Morton's neuroma is a commonly encountered cause of forefoot pain, which may limit weight-bearing activities and footwear choices. Although the aetiology and pathomechanism of this condition is controversial, the histological endpoint is well established as benign perineural fibrosis 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. In this paper, the authors review the anatomy of the common plantar digital nerves and surrounding structures in the forefoot, which are deemed relevant to the understanding of Morton's neuroma, especially from a sonographic point of view. Several theories of the pathomechanism of Morton's neuroma are briefly discussed. The main purpose of this article is to illustrate the ultrasound techniques for evaluating Morton's neuroma and performing ultrasound-guided corticosteroid injections.

Non-surgical treatments for Morton's neuroma: A systematic review

TITLE

Non-surgical treatment for Morton's neuroma: a systematic review.

BACKGROUND

Morton's neuroma (MN) is an entrapment degenerative neuropathy with a strong predilection for the 3rd interdigital web space. The objective of our study was to identify the most significant evidence produced for the non-operative treatment of Morton's neuroma and assess outcomes of these interventions.

METHOD

The electronic databases Medline, Ovid EMBASE, CINAHL and Cochrane CENTRAL from inception to October 2018 were searched. Two independent reviewers assessed the quality of the studies using the Modified Coleman Criteria. Statistics were combined across cohort studies to calculate pooled mean results, and improvements in outcomes.

RESULTS

Initial electronic and hand search identified 486 studies. After title and abstract review there were 38 that went on to full-text review. Finally, 22 studies were included in the final review. We identified 9 different non-operative treatment modalities; Corticosteroid injection, Alcohol injection, Extra-corporeal Shockwave therapy (ESWT), Radiofrequency Ablation (RFA), Cryoablation, Capsaicin injection, Botulinum toxin, Orthosis and YAG Laser Therapy. Corticosteroid showed a statistically significant reduction in mean VAS over all their studies (p < 0.01), with 50% success at 12 months. Alcohol showed promising short-term pain-relieving results only. Orthotics, Capsaicin injections, Cryoablation, Botulinum toxin, RFA and ESWT did show statistically significant improvements, but with limitation to their application.

CONCLUSION

Following review, the authors would recommend the use of corticosteroid injections to treat Morton's neuromas. The authors feel that radio-frequency ablation and cryoablation would benefit from further well designed randomised controlled trials.

The effectiveness of shoe modifications and orthotics in the conservative treatment of Civinini-Morton syndrome: state of art

Civinini Morton’s Syndrome (CMS), better known as Morton’s Neuroma, is a benign enlargement that typically affects the third common digital branch of the plantar nerve. It is a common cause of metatarsalgia leading to debilitating pain. It prefers the female gender, with a female to male ratio of 5:1 and an average age of 50 years at time of surgery. Precise aetiology remains under debate, with four etiopathogenetic theories often cited in the literature. Clinical symptoms, physical exam and instrumental evidence are important in assessing and grading the disease. Biomechanics seem to play an important role, especially regarding the usefulness of correct footwear. 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 CMS, 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 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 analysed 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. (www.actabiomedica.it)

Can percutaneous alcoholization of Morton's neuroma with phenol by electrostimulation guidance be an alternative to surgical excision? Long-term results

BACKGROUND

Percutaneous alcoholization with phenol by electrostimulation guidance for the treatment of Morton's neuroma is proposed to determine a permanent chemical neurolysis.

METHODS

115 patients for 125 Morton's neuromas were treated. Ten patients were affected by multiple neuromas. Visual Analogue Scale and AOFAS score were used for the clinical assessment.

RESULTS

The mean follow-up was 8,3 years. The pre-alcoholization VAS was 85.84 ± 12.00, while at follow-up scored 28.85 ± 31.35, showing a significant decrease improving in 113/125 cases (90.4%). Treatment was considered successful with a reduction of the VAS value superior to 50% in 89 out of 125 patients (71.2%). The mean overall AOFAS score at -up was 85.09 ± 13.41.

CONCLUSIONS

Needle-electrode guided percutaneous alcoholization is an outpatient, minimally invasive procedure with low rate of complications. Better results of those obtained with traditional conservative treatments and comparable with those reported with other alcohols injections or surgical nerve excision were observed.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Morton's neuroma - Current concepts review

Morton's neuroma is a common pathology affecting the forefoot. It is not a true neuroma but is fibrosis of the nerve. This is caused secondary to pressure or repetitive irritation leading to thickness of the digital nerve, located in the third or second intermetatarsal space. The treatment options are: orthotics, steroid injections and surgical excision usually performed through dorsal approach. Careful clinical examination, patient selection, pre-operative counselling and surgical technique are the key to success in the management of this condition.

Scientific Evidence in the Treatment of Metatarsalgia

Metatarsalgia is a common foot disease with a multitude of causes. Proper identification of underlying diseases is mandatory to formulate an adequate treatment. Multiple surgical solutions are available to treat metatarsalgia. Only limited scientific evidence is available in the literature. However, most of the techniques used in the treatment of metatarsalgia seem to be reasonable with acceptable results.

Morton's Neuroma Excision: What Are We Really Doing? Which Retractor Is Superior?

BACKGROUND

When using a dorsal approach for Morton's neuroma excision, the most common complication is recurrent Morton's neuroma. The present cadaveric study demonstrates how far proximally the nerve is resected during a dorsal approach and examines both the laminar spreader and Gelpiretractor to determine which instrument facilitates maximal proximal resection of the nerve.

METHODS

This study involved 12 fresh-frozen cadaver specimens, each of which underwent a dorsal approach to the interdigital nerve with proximal resection. Either a laminar spreader or a Gelpi retractor was used to improve visualization of the intermetatarsal space. The interdigital nerve was then resected, and the lengths of the cut nerves were compared based on the retractor employed.

RESULTS

The mean length of proximal resection in the second intermetatarsal space was 2.42 cm when using the laminar spreader and 1.93 cm when using the Gelpi retractor (P = .252). In the third intermetatarsal space, the mean length of proximal resection was 2.14 cm when using the Laminar spreader and 1.48 cm when using the Gelpi retractor (P = .166).

CONCLUSION

This study demonstrates how far proximal the interdigital nerve is resected during a dorsal approach to Morton's neuroma and shows no statistically significant difference between the Laminar spreader and the Gelpi retractor. Levels of Evidence: Level V: Cadaver study.

The effectiveness of non-surgical interventions for common plantar digital compressive neuropathy (Morton's neuroma): a systematic review and meta-analysis

Background

Morton’s neuroma (MN) is a compressive neuropathy of the common plantar digital nerve. It is a common compressive neuropathy often causing significant pain which limits footwear choices and weight bearing activities. This paper aims to review non-surgical interventions for MN, to evaluate the evidence base for the clinical management of MN.

Methods

Electronic biomedical databases (CINAHL, EMBASE, MEDLINE and Cochrane) were searched to January 2018 for studies evaluating the effectiveness of non-surgical interventions for Morton’s neuroma. Outcome measures of interest were treatment success rate (SR) (binary) and pain as measured using 100-point visual analogue scale (VAS) (continuous). Studies with and without control groups were included and were evaluated for methodological quality using the Downs and Black Quality Index. Results from randomised controlled trials (RCT) were compared between-groups, and case series were compared pre- versus post-treatment. Effect estimates are presented as odds ratios (OR) for binary data or mean differences (MD) for continuous data. Random effects models were used to pool effect estimates across studies where similar treatments were used. Heterogeneity was assessed using the I² statistic.

Results

A total of 25 studies met the inclusion criteria, seven RCTs and 18 pre/post case series. Eight different interventions were identified, with corticosteroid or sclerosing injections being the most often reported (seven studies each). Results from a meta-analysis of two RCTs found corticosteroid injection decreased pain more than control on VAS (WMD: -5.3, 95%CI: -7.5 to − 3.2). Other RCTs reported efficacy of: manipulation/mobilisation versus control (MD: -15.3, 95%CI: -29.6 to − 1.0); extracorporeal shockwave therapy versus control (MD: -5.9, 95%CI: -21.9 to 10.1). Treatment success was assessed for extracorporeal shockwave therapy versus control (OR: 0.3, 95%CI: 0.0 to 7.1); and corticosteroid injection vs footwear/padding (OR: 6.0, 95%CI: 1.9 to 19.2). Sclerosing and Botox injections, radiofrequency ablation and cryoneurolysis have been investigated by case series studies, however these were of limited methodological quality.

Conclusions

Corticosteroid injections and manipulation/mobilisation are the two interventions with the strongest evidence for pain reduction, however high-quality evidence for a gold standard intervention was not found. Although the evidence base is expanding, further high quality RCTs are needed.

Electronic supplementary material

The online version of this article (10.1186/s13047-019-0320-7) contains supplementary material, which is available to authorized users.

Mechanical Metatarsalgia as a Risk Factor for Relapse of Morton's Neuroma After Ultrasound-Guided Alcohol Injection

Although many treatment modalities are available for Morton's neuroma, the injection of the neuroma with alcohol has gained popularity. However, recently, some investigators have observed a progressive deterioration in pain scores for patients initially pain free after the treatment. The purpose of the present retrospective comparative study was to determine whether mechanical metatarsalgia is related to symptom recurrence. We included 104 consecutive cases of ultrasound-guided alcohol injection for Morton's neuroma in 92 patients. Of these 104 cases, 51 were in group A (49%; Morton's neuroma) and 53 in group B (51%; Morton's neuroma associated with mechanical metatarsalgia). We evaluated each patient using a visual analog scale and American Orthopaedic Foot and Ankle Society forefoot scale, and Johnson satisfaction scale, with a mean follow-up period of 24 (range 12 to 39) months. Concomitant functional and mechanical disorders have been identified and treated with orthopedic inserts. The present study compared the clinical results and recurrence of symptoms in patients with isolated Morton's disease or Morton's disease associated with mechanical metatarsalgia. Of the 104 cases, the patients for 93 cases (89%) were completely satisfied or satisfied with minor reservations. No major complications developed. Symptoms recurred in 6 patients (6%), in whom neuroma was associated with mechanical disorders (p = .0269). Ultrasound-guided alcohol injection of Morton's neuroma is a relatively safe and well-tolerated treatment. Symptom recurrence is often associated with mechanical metatarsalgia. The treatment of the concomitant anatomical and functional disorders that target the genesis of the neuroma has an important role in the prevention of recurrence of this pathology.

Role of imaging methods in diagnosis and treatment of Morton's neuroma

Among the many causes of forefoot pain, Morton's neuroma (MN) is often suspected, particularly in women, due to its high incidence. However, there remain controversies about its relationship with symptomatology and which diagnostic and treatment choices to choose. This article mainly focuses on the role of the various imaging methods and their abilities to support an accurate diagnosis of MN, ruling out other causes of forefoot pain, and as a way of providing targeted imaging-guided therapy for patients with MN.

Uses of Braces and Orthotics for Conservative Management of Foot and Ankle Disorders

Nonsurgical management is almost always considered the first-line treatment for the vast majority of foot and ankle pathologies. Foot orthoses, shoe modifications, and therapeutic footwear are considered essential tools for successful conservative management of different foot and ankle disorders. Orthopedic foot and ankle surgeons should have a meticulous understanding of the lower extremity biomechanics as well as the pathoanatomy and the sequelae of diseases affecting the foot and/or ankle. This is essential to the understanding of the desired effects of the different inserts, orthotics, shoe modifications, or braces that may be prescribed for these conditions. In this article, we will summarize the orthoses used for treatment of the most commonly encountered foot and ankle pathologies, with the exclusion of treatment for the diabetic foot because of the unique requirements of that disease process.

Short term comparison between blind and ultrasound guided injection in morton neuroma

OBJECTIVE

The aim of this work is to compare the effectiveness of blind and ultrasound-guided injection for Morton's neuroma (MN) to determine which is more appropriate as the initial procedure in conservative treatment.

METHODS

This is an evaluator-blinded randomised trial. Of the 56 included patients, 27 were assigned to the blind group (A) and 29 to the ultrasound-guided group (B). Injection includes 1 ml of 2% mepivacaine and 40 mg of triamcinolone in each web space with MN. The included patients were assessed clinically by VAS score and the Manchester Foot Pain and Disability Score (MFPDS). The follow-up was performed at 15 days, 1 month, 45 days, 2 months, 3 months and 6 months after the initial injection.

RESULTS

No differences in age or clinical measurements were found at presentation between group A and group B. At the follow-up, the ultrasound-guided group showed greater symptomatic relief at several stages of the follow-up: 45 days (VAS 3.0 ± 0.5 versus 5.5 ± 0.5, p = 0.001; MFPDS: 32.2 ± 1.8 versus 38.8 ± 2.0, p = 0.018), 2 months (VAS: 3.1 ± 0.5 versus 5.6 ± 0.5, p = 0.002; MFPDS: 31.5 ± 1.9 versus 38.5 ± 2.1, p = 0.020) and 3 months (VAS: 3.1 ± 0.4 versus 5.2 ± 0.6, p = 0.010; MFPDS: 31.2 ± 1.9 versus 37.7 ± 2.4, p = 0.047).

CONCLUSION

Injection of MN under ultrasound guidance provides a statistically significant improvement at some stages of the follow-up (45 days, 2 and 3 months), compared with blind injection.

KEY POINTS

• Ultrasound-guided steroid injections in Morton's neuroma provide short-term pain relief to over 60% of the patients. • Ultrasound-guided injections in Morton's neuroma lead to a higher percentage of short-term pain relief than blind injections. • Ultrasound-guided injections in Morton's neuroma lead to a lower percentage of skin side effects than blind injections.

Risk factors and the associated cutoff values for failure of corticosteroid injection in treatment of Morton's neuroma

BACKGROUND

Understanding the risk factors that predict the prognosis of Morton's neuroma after corticosteroid injection would help clinicians determine the appropriate treatment protocol. However, the cut-off values for the risk factors are unknown. The aim of this study was to identify the risk factors and cut-off values that predict failure of corticosteroid injection in treatment of Morton's neuroma.

METHOD

Among 201 patients who had corticosteroid injection for Morton's neuroma, 40 underwent further treatment after injections. Injection was performed with ultrasound guidance following ultrasound confirmation of the diagnosis. We compared demographic information, size of the neuroma, and other comorbidities between the patients who did and did not undergo further treatment after injection in order to determine the risk factors of failure. Receiver operating characteristic (ROC) curves were constructed to determine optimal cutoff values for each risk factor.

RESULTS

Stepwise logistic regression analysis showed that larger neuromas (p < 0.001) and younger patients (p = 0.026) predicted the failure of corticosteroid injection. The optimal cutoff value for the size of the neuroma was 6.3 mm (sensitivity, 81%; specificity, 95%; positive predictive value, 84%; negative predictive value, 88%) for predicting the failure of corticosteroid injection. Age was not associated with a specific cutoff value.

CONCLUSIONS

This study found that, with a cut-off value of 6.3 mm, larger Morton's neuromas were associated with failure of corticosteroid injection.

Corticosteroid Injection for the Treatment of Morton's Neuroma: A Prospective, Double-Blinded, Randomized, Placebo-Controlled Trial

BACKGROUND

The effectiveness of corticosteroid injection for the treatment of Morton's neuroma is unclear. In addition, most of the studies related to it are case-control or retrospective case series. The purpose of this study was to compare the effectiveness between corticosteroid injection associated with local anesthetic and local anesthetic alone (placebo control group) for the treatment of Morton's neuroma.

METHODS

Forty-one patients with a diagnosis of Morton's neuroma were randomized to receive 3 injections of either a corticosteroid plus a local anesthetic or a local anesthetic alone. The patients and the researcher who collected data were blinded to the treatment groups. The visual analog scale for pain and the American Orthopaedic Foot & Ankle Score (metatarsophalangeal/interphalangeal score) were obtained at baseline, after each injection, and at 3 and 6 months after the last injection.

RESULTS

There were no significant between-group differences in terms of pain and function improvement at 3 and 6 months after treatment completion in comparison with baseline values. At the end of the study, 17 (48.5%) patients requested surgical excision of the neuroma: 7 (44%) in the experimental group and 10 (53%) in the control group ( P = 1.0).

CONCLUSION

The injection of a corticosteroid plus a local anesthetic was not superior to a local anesthetic alone in terms of pain and function improvement in patients with Morton's neuroma.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Corticosteroid injection for Morton's neuroma with or without ultrasound guidance: a randomised controlled trial

AIMS

The objective of this double-blind randomised controlled trial was to assess whether ultrasound guidance improved the efficacy of corticosteroid injections for Morton's neuroma (MN).

PATIENTS AND METHODS

In all, 50 feet (40 patients) were recruited for this study but five feet were excluded due to the patients declining further participation. The mean age of the remaining 36 patients (45 feet) was 57.8 years (standard deviation (sd) 12.9) with a female preponderance (33F:12M). All patients were followed-up for 12 months. Treatment was randomised to an ultrasound guided (Group A) or non-ultrasound guided (Group B) injection of 40 mg triamcinolone acetonide and 2 ml 1% lignocaine, following ultrasound confirmation of the diagnosis.

RESULTS

The mean visual analogue score for pain improved significantly in both groups (Group A - from 64 mm, sd 25 mm to 29 mm, sd 27; Group B - from 69 mm, sd 23 mm to 37 mm, sd 25) with no statistical difference between them at all time-points. The failure rate within 12 months of treatment was 11/23 (48%) and 12/22 (55%) in Groups A and B, respectively (p = 0.458). The improvement in Manchester Oxford Foot Questionnaire Index and patient satisfaction favoured Group A in the short-term (three months) that almost reached statistical significance (p = 0.059 and 0.066 respectively). However, this difference was not observed beyond three months.

CONCLUSION

This study has shown that ultrasound guidance did not demonstrably improve the efficacy of corticosteroid injections in patients with MN.

TAKE HOME MESSAGE

In the presence of a clear diagnosis of MN, a trained clinician who understands the forefoot anatomy may perform an injection without ultrasound guidance with good and safe results.

Percutaneous Image-Guided Musculoskeletal Tumor Treatments

OBJECTIVE

The purpose of this article is to review the current guidelines and recommendations for percutaneous image-guided treatment of musculoskeletal tumors.

CONCLUSION

With the ongoing technologic advances, it is essential that the musculoskeletal interventionalist is familiar with the current tools and techniques available for the treatment of soft-tissue and bone tumors. Fortunately, many of these tools are readily available in a standard interventional radiology department and can be easily applied to the musculoskeletal system.

What factors predict the need for further intervention following corticosteroid injection of Morton's neuroma?

BACKGROUND

This study investigated factors that may predict the need for Morton's neuroma (MN) to undergo further treatment within 2 years of a single ultrasound-guided corticosteroid injection.

METHODS

A retrospective study was undertaken over a three-year period. The data was stratified into two groups: Group A - did not receive further intervention and Group B - received further treatment. We investigated age, gender, neuroma size and presence of other forefoot pathology or ipsilateral neuromas.

RESULTS

54 patients (57 feet) were reviewed. 29 feet (51%) required further treatment within 2 years (11 repeat injections, 18 surgical excisions). Binary logistic regression showed that larger neuromas (p=0.011) and younger patients (p=0.007) predicted the need for further intervention but not gender (p=0.272). The distribution of concomitant forefoot pathology and ipsilateral neuromas were similar between the two groups.

CONCLUSION

Size and age appear to be predictors for further treatment of MN within 2 years of corticosteroid injection.

Ultrasound-guided alcohol injection for Morton's neuroma

BACKGROUND

Ultrasonography-guided alcohol injection (USGAI) of Morton's neuroma represents an alternative to operative treatment. Nonetheless, the literature only reports few small studies evaluating the effectiveness of the treatment. The aim of the present retrospective study was to assess the effectiveness of USGAI to treat Morton's neuroma in 508 patients at 2 medical centers.

METHODS

Between January 2001 and January 2012, 508 patients with 540 Morton's neuroma had USGAI for Morton's neuroma. Only second and third web-space neuromas were included in this study.

RESULTS

A mean number of 3.0 (range, 1 to 4) injections were performed for each neuroma. Mean local inflammatory reaction was 0.7 (range, 0 to 2). There were no other local or systemic complications. The overall mean pre-USGAI VAS score was 8.7 (range, 6 to 10), while the post-USGAI VAS score at 1 year was 3.6 (range, 0 to 9). The delta VAS between the pre- and post-USGAI was statistically significant (P < .0001). At 1-year follow-up 74.5% of patients were satisfied with the procedure.

CONCLUSION

USGAI produced encouraging results in over 500 patients affected by Morton's neuroma. The procedure proved to be safe in all patients.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

A systematic review of ultrasound-guided and non-ultrasound-guided therapeutic injections to treat Morton's neuroma

BACKGROUND

Morton's neuroma is a frequently painful condition of the forefoot, causing patients to seek medical care to alleviate symptoms. A plethora of therapeutic options is available, some of which include injection therapies. Researchers have investigated injection therapy for Morton's neuroma, and latterly the evidence base has been augmented with methods that use diagnostic ultrasound as a vehicle to deliver the injectate under image guidance for additional accuracy. To date, there seems to be no consensus that ultrasound-guided injections provide better therapeutic outcomes than nonguided injections for the treatment of Morton's neuroma.

METHODS

A systematic review was chosen because this method can undertake such a process. The review process identified 13 key papers using predetermined inclusion and exclusion criteria, which then underwent methodological quality assessment using a pretested Quality Index. A narrative synthesis of the review findings is presented in light of the heterogeneity of the data from the extraction process.

RESULTS

This systematic review provides an argument that ultrasound guidance can produce better short- and long-term pain relief for corticosteroid injections, can reduce the need for additional procedures in a series of sclerosing alcohol injections, can reduce the surgical referral rate, and can add efficacy to a single injection.

CONCLUSIONS

Ultrasound guidance should be considered for injection therapy in the management of Morton's neuroma.

Treatment of Morton neuroma with botulinum toxin A: a pilot study

Background and Objective

Morton neuroma is a common cause of metatarsalgia of neuropathic origin. Systematic reviews suggest that insufficient studies have been performed on the efficacy of the different treatments available. OnabotulinumtoxinA has shown a degree of usefulness in other conditions associated with neuropathic pain. The aim of this study was to investigate the therapeutic potential of onabotulinumtoxinA in Morton neuroma.

Patients and Methods

We present an open-label, pilot study with 17 consecutive patients with Morton neuroma and pain of more than 3 months’ duration that had not responded to conservative treatment with physical measures or corticosteroid injection. Patients received one onabotulinumtoxinA injection in the area of the neuroma. The main outcome measure was the variation in the pain on walking evaluated using a visual analogue scale (VAS) before treatment and at 1 and 3 months after treatment. The secondary outcome was the change in foot function, which was assessed using the Foot Health Status Questionnaire.

Results

In the overall group, the mean initial VAS score on walking was 7. This mean score had fallen to 4.8 at 1 month after treatment and to 3.7 at 3 months. Twelve patients (70.6 %) reported an improvement in their pain and five patients (29.4 %) reported no change; exacerbation of the pain did not occur in any patient. Improvements were also observed in two of the dimensions of the Foot Health Status Questionnaire: foot pain, which improved from a mean of 38.88 before treatment to 57 at 3 months, and foot function, which improved from a mean of 42.27 before treatment to 59.9 at 3 months. Clinical variables including age, sex, site and size of the lesion, standing activity, weekly duration of walking, footwear, foot type and footprint had no influence on the outcome. No adverse effects were reported.

Conclusions

In this pilot study, injection with onabotulinumtoxinA was shown to be of possible usefulness to relieve the pain and improve function in Morton neuroma. This finding opens the door to further clinical research.

Alcohol injection for Morton's neuroma: a five-year follow-up

BACKGROUND

Although many treatment modalities are available for Morton's neuroma (MN), studies looking at the long-term effectiveness of most forms of treatment are scarce. The injection of MN with alcohol has gained popularity over the past 10 years with widespread media coverage. Many surgeons have anecdotally questioned the long-term effectiveness of this treatment. We reviewed a cohort of patients at an average 5-year follow-up to assess the medium-term results of alcohol injection.

METHODS

We used the modified Johnson score and visual analogue scales to assess 45 of the original cohort of patients with an average follow-up of 61 months (range, 33-73 months). Any complications from the procedure were also noted.

RESULTS

Our results indicated that by 5 years, 16 of 45 patients had undergone surgical treatment and a further 13 patients had return of symptoms. Only 29% (13/45) remained symptom free. The visual analog scale and modified Johnson scores showed statistically significant deterioration in patients' symptoms at 5 years following alcohol injection.

CONCLUSION

Injection with alcohol sclerosant for MN has been marketed as a definitive management option comparable to surgical excision. Our investigation illustrated that although short-term results are encouraging, alcohol injection does not offer permanent resolution of symptoms for most patients and can be associated with considerable morbidity. Our investigation provides the only long-term data for alcohol injection treatment of MN.

LEVEL OF EVIDENCE

Level II, prospective case series.

The diagnosis and management of Morton's neuroma: a literature review

Morton's neuroma is a common condition mainly affecting middle aged women, and there are many proposed etiological theories involving chronic repetitive trauma, ischemia, entrapment, and intermetatarsal bursitis. Incorrect terminology suggests that the underlying pathological process is a nerve tumor, although histological examination reveals the presence of inflammatory tissue-that is, perineural fibrosis. The common digital nerve and its branches in the third planter webspace are most commonly affected. Diagnosis is usually made through history taking and clinical examination but may be aided by ultrasonography and magnetic resonance imaging. Current nonoperative treatment strategies include shoe-wear modifications, custom made orthoses, and injections of local anesthetic agents, sclerosing agents, and steroids. Operative management options primarily involve either nerve decompression or neurectomy. We have reviewed the published literature to evaluate the outcomes of the available diagnostic modalities and treatment options and present an algorithm for clinical practice.

Methylprednisolone injections for the treatment of Morton neuroma: a patient-blinded randomized trial

BACKGROUND

Morton neuroma is a common cause of neuralgia affecting the web spaces of the toes. Corticosteroid injections are commonly administered as a first-line therapy, but the evidence for their effectiveness is weak. Our primary research aim was to determine whether corticosteroid injection is an effective treatment for Morton neuroma compared with an anesthetic injection as a placebo control.

METHODS

We performed a pragmatic, patient-blinded randomized trial set within hospital orthopaedic outpatient clinics in Edinburgh, United Kingdom. One hundred and thirty-one participants with Morton neuroma (mean age, fifty-three years; 111 [85%] female) were randomized to receive either corticosteroid and anesthetic (1 mL methylprednisolone [40 mg] and 1 mL 2% lignocaine) or anesthetic alone (2 mL 1% lignocaine). An ultrasonographic image was obtained before treatment, and injections were performed with the needle placed under ultrasonographic guidance. The primary outcome was the difference in patient global assessment of foot health between the two groups at three months after injection. This was measured with use of a 100-unit visual analog scale (VAS) anchored by "best imaginable health state" and "worst imaginable health state."

RESULTS

Compared with the control group, global assessment of foot health in the corticosteroid group was significantly better at three months (mean difference, 14.1 scale points [95% confidence interval, 5.5 to 22.8 points]; p = 0.002). The difference between the groups was also significant at one month. Significant and nonsignificant improvements associated with the corticosteroid injection were observed for measures of pain, function, and patient global assessment of general health at one and three months after injection. The size of the neuroma as determined by ultrasonography did not significantly influence the treatment effect.

CONCLUSIONS

Corticosteroid injections for Morton neuroma can be of symptomatic benefit for at least three months.

Computed tomography analysis of third webspace injections for interdigital neuroma

BACKGROUND

Injection for interdigital neuroma (IDN) may not selectively target the common digital nerve. We investigated the anatomical localization and extent of extravasation with injection for IDN.

METHODS

Two fellowship-trained foot and ankle surgeons injected radiopaque contrast into the third webspace of 49 cadaveric specimens (29 with 2 mL and 20 with 1 mL). Computed tomography scan of each specimen was obtained. An independent blinded foot and ankle surgeon analyzed the scans.

RESULTS

All injections were accurate. Contrast was found in the second (greater than 70%) and fourth (greater than 30%) webspaces in both injection volume groups. No contrast was found within the third metatarsophalangeal joint. Extravasation extent was significantly greater with 2 mL versus 1 mL of solution in the medial to lateral (27.9 [7.8] mm vs 23.7 [6.0] mm; P = .05) and distal to proximal (52.1 [13.7] mm vs 40.4 [16.1] mm; P = .01) planes. No differences were observed in extravasation extent between surgeons.

CONCLUSION

Injection for IDN was accurate, and extravasation extended into adjacent webspaces in a large percentage of specimens with both solution volumes. Lower extent of extravasation with 1 mL of solution did not indicate better selectivity of injection.

CLINICAL RELEVANCE

Steroid injections for interdigital neuroma were accurate for therapeutic purposes but not diagnostic, except potentially for distinguishing webspace pain from joint pain.

Efficacy of corticosteroid injection versus size of plantar interdigital neuroma

BACKGROUND

The aim of this prospective study was to assess the effectiveness of a single ultrasound-guided steroid injection in the treatment of Morton's neuromas and whether the response to injection correlates with the size of the neuroma.

METHODS

Forty-three patients with clinical features of Morton's neuroma underwent ultrasound scan assessment. Once the lesion was confirmed in the relevant web space, a single corticosteroid injection was given using 40 mg of methylprednisolone along with 1% lidocaine. All scans and injections were performed by a single musculoskeletal radiologist. Patients were divided into two groups on the basis of the size of the lesion measured on the scan. Group 1 included patients with neuromas of 5 mm or less and group 2 patients had neuromas larger than 5 mm. A visual analog scale (VAS) for pain (scale 0 to 10), the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Johnson satisfaction scale were used to assess patients before injection and then at 6 weeks, 6 months, and 12 months following the injection. Thirty-nine patients had confirmed neuromas. Group 1 (lesion ≤ 5 mm) included 17 patients (mean age, 30 years) (7 males, 10 females) and group 2 (lesion >5 mm) had 22 patients (mean age, 33 years) (8 males, 14 females).

RESULTS

VAS scores, AOFAS scores, and Johnson scale improved significantly in both groups at 6 weeks (p < .0001). At 6 months postinjection, this improvement remained significant only in group 1 with all scores (p < . 001). At 12 months, there was no difference between both groups and outcome scores nearly approached preinjection scores. At the final review, two patients in group 1 and four patients in group 2 had severe recurrent symptoms and therefore underwent surgical excision of the neuroma after they rejected the offer for a repeat injection (p = 0.6).

CONCLUSION

A single ultrasound-guided corticosteroid injection resulted in generally short-term pain relief for symptomatic Morton's neuromas. The effectiveness of the injection appears to be more significant and long-lasting for lesions smaller than 5 mm.

Plantar approach for excision of a Morton neuroma: a long-term follow-up study

BACKGROUND

When nonsurgical treatment of a Morton neuroma is unsuccessful, neurectomy is indicated. The purpose of the present retrospective study was to evaluate the long-term outcomes, complications, and adverse events following a distal plantar transverse incision for the excision of an intermetatarsal neuroma.

METHODS

We conducted a retrospective review of 168 consecutive patients who underwent surgical excision of a Morton neuroma that had been unresponsive to nonsurgical treatment. The clinical diagnosis was confirmed by means of magnetic resonance imaging and histological analysis. All patients underwent excision of the neuroma through a distal transverse plantar approach; concomitant foot and ankle disorders were also treated. Postoperatively, a three-grade patient satisfaction scale was administered to assess the results of the procedure and a clinical examination was performed for all patients.

RESULTS

One hundred and sixty patients (204 feet, 227 neuromas) were assessed at a median of 7.1 ± 3.9 years (range, one to twenty-one years) postoperatively. A good result was reported for 143 patients (89.4%); a fair result, for eleven (6.9%); and a poor result, for six (3.8%). The eleven patients with a fair result reported scar-related symptoms such as skin hardening, loss of sensation at the incision site, discomfort wearing shoes with high heels, and local paresthesias with no recurrence of the neuroma. The six patients with a poor result reported pain and paresthesias, and the recurrence of a neuroma was confirmed at the time of reoperation.

CONCLUSIONS

Producing a marked reduction in pain and high overall patient satisfaction, a distal transverse plantar incision is comparable with other surgical approaches for the surgical treatment of a Morton neuroma.

Ultrasound guided alcohol ablation of Morton's neuroma

BACKGROUND

Morton's neuroma is a common cause of metatarsalgia. This study evaluated the efficacy of ultrasound guided alcohol injection as a treatment for this condition.

METHOD

Data from 87 treatment courses were included in this study with a mean follow of 14.3 months.

RESULTS

Technical success was 100%. One patient developed symptoms consistent with an allergic reaction to the injection and one patient declined further injection because of periprocedural pain. Partial or total treatment response was achieved in 66%, with 32% of patients having complete resolution of pain. The median visual analogue score (VAS) decreased from 8 pre-procedure to 4 post-procedure (p < 0.0001). Procedural success was greater in patients under 55 years old and in those with solitary neuromas. Seventeen patients (20%) went on to have surgery due to continuing pain.

CONCLUSION

Ultrasound guided alcohol ablation for the treatment of Morton's neuroma was a safe procedure that significantly reduced pain and may offer an alternative therapy to surgery.

Alcohol sclerosing therapy is not an effective treatment for interdigital neuroma

BACKGROUND

Alcohol sclerosing therapy has been reported as a safe and effective means of treating interdigital neuromas, both with or without ultrasound. The use of ultrasound introduces beside the ultrasound device, increased cost, and the need for skilled technicians and may reduce usability, especially in the outpatient clinic. We report a series of patients with interdigital neuroma treated using ethanol sclerosing therapy in a clinic setting without the use of ultrasound.

MATERIALS AND METHODS

We retrospectively reviewed charts of 32 consecutive patients who were enrolled to receive a series of sclerosing ethanol injections from June 2009 to April 2010 for the treatment of a painful interdigital neuroma. Plain radiographs and MRI scans were obtained if clinically indicated to assistance with the diagnosis. Duration and quality of symptoms were recorded and current pain levels were evaluated on a visual analog pain scale. Previous treatments, including orthotic use, corticosteroid injection, or prior neuroma resection were reported. A solution of 1 ml consisting of 20% ethanol and 0.25% bupivacain solution was injected without the use of ultrasound into the affected webspace. The mixture was provided by the local pharmacy. Technical success was confirmed by the temporary resolution of pain following local anesthetic infiltration. If still symptomatic, an injection was repeated every 2 weeks, with most patients receiving a series of four injections. Pain was evaluated on a visual analog pain scale at each visit. Treatment success was defined as resolution of pain as expressed by the patient.

RESULTS

Of the 32 patients successful relief of symptoms was only achieved in seven patients, while 25 showed no significant reduction of symptoms and considered or underwent a surgical excision.

CONCLUSION

Alcohol sclerosing therapy administered in the clinic setting without alcohol is not an effective treatment in the nonoperative management of painful interdigital neuromas and has been abandoned in our clinic.

Morton's neuroma

Morton neuroma is a common source of forefoot pain. This condition is more correctly termed as interdigital nerve compression and is not a true neuroma. Although Morton neuroma is a common diagnosis, debate exists as to the best surgical and nonsurgical treatments. This article discusses the pathogenesis, diagnosis, nonsurgical and surgical management, and surgical complications of this common disorder.

Results of operative treatment of double Morton's neuroma in the same foot

BACKGROUND

Double Morton's neuroma in one foot has rarely been reported in the literature.

METHODS

In the current study, the authors treated 11 patients with a total of 14 cases of double Morton's neuroma in one foot. During the research period, 157 cases of Morton's neuroma were treated with surgery. The neuromas were excised through a single skin incision, and all operations occurred within a 17-month period from April 2005 to October 2006.

RESULTS

The mean preoperative AOFAS score was 54 points, and the mean postoperative AOFAS score was 78 points. Seven patients underwent additional foot procedures, and the other half did not. There was no significant difference in improvement in the postoperative AOFAS score between patients treated with a combined procedure and patients treated without a combined procedure. Protective sensation was present postoperatively in most patients, except for the four patients who had hypoesthesia or hyperesthesia. No patients were administered anesthesia.

CONCLUSIONS

We report success in surgical excision of double Morton's neuroma in one foot through a single skin incision, and recommend that in cases of compound diseases, excision of a double Morton's neuroma must be performed as a combination procedure.

Custom-made foot orthoses for the treatment of foot pain

BACKGROUND

Custom foot orthoses are commonly recommended for the treatment of foot pain.

OBJECTIVES

To evaluate the effectiveness of custom foot orthoses for different types of foot pain.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), CINAHL (from January 1982) and the Physiotherapy Evidence Database (PEDro) (to June 2007). We also contacted authors of included trials and known researchers in the field and checked the reference lists of included trials to identify trials. No language or publication restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials evaluating custom-made foot orthoses for any type of foot pain. Outcomes included quantifiable levels of foot pain, function, disability, health-related quality of life, participant satisfaction, adverse effects and compliance.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, rated methodological quality and cross checked data extraction. Data were analysed separately for different diagnoses of foot pain and follow-up time points.

MAIN RESULTS

Eleven trials involving 1332 participants were included: five trials evaluated custom-made foot orthoses for plantar fasciitis (691 participants); three for foot pain in rheumatoid arthritis (231 participants); and one each for foot pain in pes cavus (154 participants), hallux valgus (209 participants) and juvenile idiopathic arthritis (JIA) (47 participants). Comparisons to custom-made foot orthoses included sham orthoses; no intervention; standardised interventions given to all participants; non-custom (prefabricated) foot orthoses; combined manipulation, mobilisation or stretching; night splints; and surgery. Follow up ranged from one week to three years. Custom-made foot orthoses were effective for painful pes cavus (NNTB:5), rearfoot pain in rheumatoid arthritis (NNTB:4), foot pain in JIA (NNTB:3) and painful hallux valgus (NNTB:6); however, surgery was even more effective for hallux valgus and non-custom foot orthoses appeared just as effective for JIA but the analysis may have lacked sufficient power to detect a difference in effect. It is unclear if custom-made foot orthoses were effective for plantar fasciitis or metatarsophalangeal joint pain in rheumatoid arthritis. Custom-made foot orthoses were a safe intervention in all studies.

AUTHORS' CONCLUSIONS

There is limited evidence on which to base clinical decisions regarding the prescription of custom-made foot orthoses for the treatment of foot pain. Currently, there is gold level evidence for painful pes cavus and silver level evidence for foot pain in JIA, rheumatoid arthritis, plantar fasciitis and hallux valgus.

Régression du névrome de Morton après infiltration de corticostéroïdes

Morton neuroma is a non neoplastic lesion corresponding to perineural fibrosis encircling the common interdigital plantar nerve. Several therapeutic approaches are possible: conservative treatment or surgery. We report a case treated by local steroid injection where follow-up MR showed near complete regression of the lesion. Although local injection of steroid is a classical treatment, it is the first time to our knowledge that resolution or such a striking diminution of size is reported after infiltration.