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

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.

Common Painful Foot and Ankle Conditions: A Review

Importance

Morton neuroma, plantar fasciitis, and Achilles tendinopathy are foot and ankle conditions that are associated with pain and disability, but they can respond to nonoperative treatment.

Observations

Morton neuroma, consisting of interdigital neuronal thickening and fibrosis, is characterized by burning pain in the ball of the foot and numbness or burning pain that may radiate to the affected toes (commonly the third and fourth toes). First-line nonoperative therapy consists of reducing activities that cause pain, orthotics, and interdigital corticosteroid injection; however, approximately 30% of patients may not respond to conservative treatment. Plantar fasciitis accounts for more than 1 million patient visits per year in the US and typically presents with plantar heel pain. Fifteen years after diagnosis, approximately 44% of patients continue to have pain. First-line nonoperative therapy includes stretching of the plantar fascia and foot orthotics, followed by extracorporeal shockwave therapy, corticosteroid injection, or platelet-rich plasma injection. Midportion Achilles tendinopathy presents with pain approximately 2 to 6 cm proximal to the Achilles insertion on the heel. The primary nonoperative treatment involves eccentric strengthening exercises, but extracorporeal shockwave therapy may be used.

Conclusions and Relevance

Morton neuroma, plantar fasciitis, and Achilles tendinopathy are painful foot and ankle conditions. First-line therapies are activity restriction, orthotics, and corticosteroid injection for Morton neuroma; stretching and foot orthotics for plantar fasciitis; and eccentric strengthening exercises for Achilles tendinopathy.

Infiltrative Type I Collagen in the Treatment of Morton's Neuroma: A Mini-Series

Morton's neuroma (MN) is a compressive neuropathy of the common plantar digital nerve, most commonly affecting the third inter-digital space. The conservative approach is the first recommended treatment option. However, other different approaches have been proposed, offering several options of treatments, where, several degrees of efficacy and safety have been reported. We treated five consecutive patients affected by MN through three indirect ultrasound-guided injections of type I porcine collagen at weekly intervals. All patients were assessed before the treatment, after the treatment and up to 6 months after the last injection via AOFAS and VNS scores for pain, in which the function and pain were evaluated, respectively. In all patients, both analyzed variables progressively ameliorated, with benefits lasting until the last follow-up. The trend of the scores during the follow-up showed significant statistical differences. No side effects occurred. To our knowledge, this is the first study on injections of type I porcine collagen for the treatment of Morton's neuroma. Future research is needed to confirm the positive trend achieved in this MN mini-series.

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.

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.

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.

Fascial Manipulation Technique in the Conservative Management of Morton's Syndrome: A Pilot Study

Background and Objective: Morton’s syndrome (MS) is a common cause of neuropathic chronic forefoot pain, characterised by the development of a swelling of the common digital plantar nerve, whose aetiology is not fully known. There is currently no gold standard of treatment; nonoperative management commonly involves manual therapies, orthoses therapy and infiltrative techniques, while surgery is indicated after failure of conservative measures. The present preliminary study prospectively evaluates patients affected by MS treated by Fascial Manipulation technique (FM), a noninvasive manual therapy, focused on the release of the deep fascia, reducing its stiffness. Materials and Methods: Patients with clinical and sonographic diagnosis of MS with at least a 4-month history of neuropathic symptoms underwent a cycle of three weekly FM sessions. Clinical follow-up, including VAS and AOFAS scores, was performed 21 days (T1) and 3 months (T2) after treatment. Results: Nine patients, among 28 recruited initially, completed the manual therapy sessions and relative follow-up points. This noninvasive pain treatment led to significant improvement of VAS (p = 0.0034) and AOFAS scores (p = 0.0240) at the first follow-up (T1). At 3-month follow-up (T2), both scores decreased slightly, remaining however superior to the pre-treatment values. Only VAS was still significant (p = 0.0184). Conclusions: Despite the small size of the case series, this pilot study is unique in supporting Fascial Manipulation in the nonoperative treatment of MS. Further studies are needed with a large cohort of gender balanced patients to confirm the encouraging results obtained.

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.

Ultrasound-guided treatment of Morton's neuroma

Morton’s neuroma is a painful lesion of the interdigital nerve, usually at the third intermetatarsal space, associated with fibrotic changes in the nerve, microvascular degeneration, and deregulation of sympathetic innervation. Patients usually present with burning or sharp metatarsalgia at the dorsal or plantar aspect of the foot. 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. Ultrasound aids in the accurate diagnosis of Morton’s neuroma and guides the aforementioned treatment, so that significant and potentially long-lasting pain reduction can be achieved. In cases of initial treatment failure, the procedure can be repeated, usually leading to the complete remission of symptoms. Current data shows that minimally invasive treatments can significantly reduce the need for subsequent surgery in patients with persistent Morton’s neuroma unresponsive to conservative measures. The purpose of this review is to present current data on the application of ultrasound for the diagnosis and treatment of Morton’s neuroma, with emphasis on the outcomes of ultrasound-guided treatments.

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.

Treating Morton's neuroma by injection, neurolysis, or neurectomy: a systematic review and meta-analysis of pain and satisfaction outcomes

BACKGROUND

Individual evidence suggests that multiple modalities can be used to treat entrapment pathology by Morton's neuroma, including injection, neurolysis, and neurectomy. However, their impacts on patient pain and satisfaction have yet to be fully defined or elucidated. Correspondingly, our aim was to pool systematically identified metadata and substantiate the impact of these different modalities in treating Morton's neuroma with respect to these outcomes.

METHODS

Searches of 7 electronic databases from inception to October 2019 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. The incidences of outcomes were extracted and pooled by random-effects meta-analysis of proportions.

RESULTS

A total of 35 articles satisfied all criteria, reporting a total of 2998 patients with Morton's neuroma managed by one of the three modalities. Incidence of complete pain relief after injection (43%; 95% CI, 23-64%) was significantly lower than neurolysis (68%; 95% CI, 51-84%) and neurectomy (74%; 95% CI, 66-82%) (P = 0.02). Incidence of complete satisfaction after injection (35%; 95% CI, 21-50%) was significantly lower than neurolysis (63%; 95% CI, 50-74%) and neurectomy (57%; 95% CI, 47-67%) (P < 0.01). The need to proceed to further surgery was significantly greater following injection (15%; 95% CI, 9-23%) versus neurolysis (2%; 95% CI, 0-4%) or neurectomy (5%; 95% CI, 3-7%) (P < 0.01). Incidence of procedural complications did not differ between modalities (P = 0.30).

CONCLUSIONS

Although all interventions demonstrated favorable procedural complication incidences, surgical interventions by either neurolysis or neurectomy appear to trend towards greater incidences of complete pain relief and complete patient satisfaction outcomes compared to injection treatment. The optimal decision-making algorithm for treatment for Morton's neuroma should incorporate these findings to better form and meet the expectations of patients.

Patient-Related Outcome Measures (PROMs) With Nonoperative and Operative Management of Morton's Neuroma

BACKGROUND

Morton's neuroma is associated with chronic pain and disability. There is a paucity of literature regarding patient-related outcome measures (PROMs) in patients managed nonoperatively. We sought to investigate nonoperative and operative management of Morton's neuroma using PROMs in patients with follow-up to 1 year.

METHODS

We conducted a prospective observational study and collected data on all patients with a new diagnosis of Morton's neuroma treated from February 2016 until April 2018. Primary outcome measures were the Manchester-Oxford Foot Questionnaire (MOXFQ) for pain, EuroQoL (EQ) time trade-off (TTO), and EQ visual analog scale (VAS) taken preoperatively and at 52 weeks postoperatively. Forty-four patients were treated nonoperatively and 94 patients were treated operatively.

RESULTS

Pretreatment and 52-week scores were 55.7 and 43.10 (nonoperative) and 63.7 and 40.1 (operative) for MOXFQ (pain), 0.72 and 0.82 (nonoperative) and 0.68 and 0.82 (operative) for EQ-TTO, and 71.5 and 76.2 (nonoperative) and 73.1 and 68.7 (operative) for EQ-VAS. There was a statistically significant improvement in MOXFQ (pain) in nonoperative (P = .02) and operative groups (P < .001). There was a statistically significant improvement in EQ-TTO in the operative group only (P = .01).

CONCLUSION

This is the largest study investigating outcomes to 12 months of both nonoperative and operatively managed patients with Morton's neuroma. Both nonoperative and operative management lead to symptom improvement at 12 months.

LEVEL OF EVIDENCE

Level III, comparative study.

Addition of corticosteroids to local anaesthetics for chronic non-cancer pain injections: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Despite common use, the benefit of adding steroids to local anaesthetics (SLA) for chronic non-cancer pain (CNCP) injections is uncertain. We performed a systematic review and meta-analysis of English-language RCTs to assess the benefit and safety of adding steroids to local anaesthetics (LA) for CNCP.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL databases from inception to May 2019. Trial selection and data extraction were performed in duplicate. Outcomes were guided by the Initiative in Methods, Measurements, and Pain Assessment in Clinical Trials (IMMPACT) statement with pain improvement as the primary outcome and pooled using random effects model and reported as relative risks (RR) or mean differences (MD) with 95% confidence intervals (CIs).

RESULTS

Among 5097 abstracts, 73 trials were eligible. Although SLA increased the rate of success (42 trials, 3592 patients; RR=1.14; 95% CI, 1.03-1.25; number needed to treat [NNT], 13), the effect size decreased by nearly 50% (NNT, 22) with the removal of two intrathecal injection studies. The differences in pain scores with SLA were not clinically meaningful (54 trials, 4416 patients, MD=0.44 units; 95% CI, 0.24-0.65). No differences were observed in other outcomes or adverse events. No subgroup effects were detected based on clinical categories. Meta-regression showed no significant association with steroid dose or length of follow-up and pain relief.

CONCLUSIONS

Addition of cortico steroids to local anaesthetic has only small benefits and a potential for harm. Injection of local anaesthetic alone could be therapeutic, beyond being diagnostic. A shared decision based on patient preferences should be considered. If used, one must avoid high doses and series of steroid injections.

CLINICAL TRIAL REGISTRATION

PROSPERO #: CRD42015020614.

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.

Injection Techniques for Common Chronic Pain Conditions of the Foot: A Comprehensive Review

Purpose of Review

This is a comprehensive literature review of the available evidence and techniques of foot injections for chronic pain conditions. It briefly describes common foot chronic pain syndromes and then reviews available injection techniques for each of these syndromes, weighing the available evidence and comparing the available approaches.

Recent Findings

Foot and ankle pain affects 20% of the population over 50 and significantly impairs mobility and ability to participate in activities of daily living (ADLs), as well as increases fall risk. It is commonly treated with costly surgery, at times with questionable efficacy. Injection therapy is challenging when the etiology is anatomical or compressive. Morton’s neuroma is a budging of the interdigital nerve. Steroid, alcohol, and capsaicin injections provide some benefit, but it is short lived. Hyaluronic acid (HA) injection provided long-term relief and could prove to be a viable treatment option. Achilles tendinopathy (AT) is most likely secondary to repeat tendon stress—platelet-rich-plasma (PRP) and prolotherapy have been trialed for this condition, but more evidence is required to show efficacy. Similar injections were trials for plantar fasciitis and achieved only short-term relief; however, some evidence suggests that PRP injections reduce the frequency of required therapy. Tarsal tunnel syndrome, a compressive neuropathy carries a risk of permanent neural injury if left untreated. Injection therapy can provide a bridge to surgery; however, surgical decompression remains the definitive therapy. When the etiology is inflammatory, steroid injection is more likely to provide benefit. This has been shown in several studies for gout, as well as osteoarthritis of the foot and ankle and treatment-refractory rheumatoid arthritis. HA showed similar benefit, possibly due to anti-inflammatory effects. Stem cell injections may provide the additional benefit of structure restoration.

Summary

Chronic foot pain is common in the general population and has significant associated morbidity and disability. Traditionally treated with surgery, these are costly and only somewhat effective. Injections provide an effective alternative financially and some evidence exists that they are effective in pain alleviation. However, current evidence is limited and the benefit described from injection therapy has been short-lived in most cases. Further studies in larger populations are required to evaluate the long-term effects of these treatments.

Mallet Toes, Hammertoes, Neuromas, and Metatarsophalangeal Joint Instability: 40 Years of Development in Forefoot Surgery

BACKGROUND

Today's foot and ankle surgeon has an enhanced understanding of forefoot pathology and treatment options compared to surgeons who practiced in previous decades. This paper summarizes developments in forefoot surgery in the past 40 years, specifically in treatments for mallet toe, hammertoe, neuroma, and metatarsophalangeal joint instability.

MATERIALS AND METHODS

A review of the literature was conducted using the PubMed search engine, with key terms including, "mallet toe," "hammertoe," "neuroma," "metatarsophalangeal joint instability," "plantar plate," and "forefoot surgery." Chapters in major orthopaedic textbooks covering these topics were also reviewed. We then chronicled the history of the diagnosis and treatment of these pathologies, with a focus on the past 40 years.

CONCLUSIONS

There have been major advances in understanding and treating forefoot pathologies in the past four decades; however, there remain areas for improvement both in the diagnosis and treatment of these problems.

LEVEL OF EVIDENCE

Level V, meta-synthesis.

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.

Intra- and Interobserver Reliability of Size Measurement of Morton Neuromas on Sonography

OBJECTIVES

Sonography is often used for analysis of Morton neuromas, but the measurement reliability is unknown. The aim of this study was to determine the intra- and interobserver reliability and precision of sonographic measurement of Morton neuromas.

METHODS

Three observers with different levels of sonography experience (observer A, expert; observer B, intermediate; observer C, beginner) performed repeated measurements of the size of Morton's neuroma in 20 patients. Intraclass correlation coefficient and limit of agreement were used to evaluate reliability and measurement precision.

RESULTS

The intraclass correlation coefficient for intraobserver reliability was 0.80, 0.71, and 0.43 (limit of agreement, 20%, 18%, and 47%) in observers A, B, and C, respectively. The intraclass correlation coefficient for interobserver reliability was 0.72, 0.38, and 0.38 (limit of agreement, 25%, 36%, and 35%) between observers A/B, A/C, and B/C, respectively.

CONCLUSIONS

The intra- and interobserver reliability values for sonographic measurement of Morton neuroma size were dependent on observer experience. Experienced observers had higher reliability, while observers who were less familiar with sonography showed moderate to low reliability.

Ultrasound-guided radiofrequency ablation for treatment of Morton's neuroma: initial experience

AIM

To assess the efficacy and safety of ultrasound-guided radiofrequency ablation (RFA) for treatment of symptomatic Morton's neuroma.

MATERIALS AND METHODS

Patients with symptomatic Morton's neuroma of the foot were referred for treatment with RFA, prior to consideration for surgery. All neuromas were proven by ultrasound imaging and had a trial of conservative management including orthotic support and/or steroid injections. Ultrasound-guided RFA was performed as an outpatient procedure under local anaesthetic. Patients were followed up at 8 weeks and 8 months. Outcomes were assessed with a visual analogue scale (VAS) score, Manchester-Oxford Foot and Ankle Questionnaire, overall patient satisfaction, and complications.

RESULTS

Twenty-two neuromas were treated with RFA under ultrasound guidance. The VAS score at 8 weeks was significantly lower than the VAS score pre-procedure (p<0.001, Wilcoxon signed ranks test) and the VAS score at 8 months was significantly lower than the VAS score at 8 weeks (p=0.008, Wilcoxon signed ranks test). At 8 months, 89% of treated patients were satisfied with the procedure outcome. No significant adverse effects were recorded.

CONCLUSION

Ultrasound-guided RFA is safe, with excellent initial results in treatment of symptomatic Morton's neuroma. Further studies on long-term outcomes and comparison to other management options will be required to establish its role in management of symptomatic Morton's neuroma.

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 I 2 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.

Morton's interdigital neuroma: instructional review

The terminology ‘Morton’s neuroma’ may represent a simplification of the clinical condition as the problem may not be a benign tumour of the nerve, but neuropathic foot pain associated with the interdigital nerve.

Foot and ankle pathomechanics leading to metatarsalgia, clinical examination and differential diagnosis of the condition and imaging of the condition, for differential diagnosis, are discussed.

Nonoperative management is recommended initially. Physiotherapy, injections (local anaesthetic, steroid, alcohol), cryotherapy, radiofrequency ablation and shockwave therapy are discussed.

Operative treatment is indicated after nonoperative management has failed. Neuroma excision has been reported to have good to excellent results in 80% of patients, but gastrocnemius release and osteotomies should be considered so as to address concomitant problems.

Key factors in the success of surgery are correct diagnosis with recognition of all elements of the problem and optimal surgical technique.

Cite this article: EFORT Open Rev 2019;4:14-24. DOI: 10.1302/2058-5241.4.180025.

[Recent progress in foot and ankle surgery]

The article focuses on the recent progress in foot and ankle surgery, including the diagnosis of disease, treatment protocols, outcomes, and evaluation tools as well as other innovations. New and accurate diagnostic modalities and measurements have undergone a breakthrough. Diagnostic modalities tend to be simpler and less expensive. Measurement tools also change to simpler and more accurate. The accuracy and efficacy of surgery and the minimally invasive method have become more popular and important. New treatments and basic research have also made breakthroughs.