Surgical treatment of Morton's neuroma: clinical results after open excision

Factors Associated With Symptom Recurrence After Surgical Treatment of Interdigital Neuroma: A Retrospective Chart Review of 127 Patients

INTRODUCTION

Interdigital neuroma (IN) is a benign enlargement of tissue surrounding the common plantar digital nerve. Although the standard surgical treatment of IN remains debated, recent attention has been given to less-invasive surgical decompression by intermetatarsal ligament (IML) release with neurolysis. This study aimed to compare the outcomes of IML release with neurolysis with standard interdigital neurectomy.

METHODS

A retrospective chart review was conducted on 350 consecutive patients who underwent surgical treatment of IN. Patients who satisfied our inclusion and exclusion criteria were categorized into two groups based on the surgical treatment received: IML release with neurolysis or interdigital neurectomy. Outcomes assessed included recurrence of symptoms, rate of revision surgery, and postoperative wound infection.

RESULTS

Of the total sample, 40 patients (31.5%) reported recurrence of symptoms within a 12-month follow-up period. Patients who underwent IML release with neurolysis had a markedly higher recurrence rate (47.50%) than those who underwent interdigital neurectomy (24.14%). The rate of postoperative wound infection was similar between the two groups. Binary logistic regression revealed that only the surgical technique was associated with the recurrence of symptoms. Despite the higher rate of symptom recurrence in the IML release with neurolysis patient group, the rate of revision surgery in those with symptom recurrence was similar between both groups.

DISCUSSION

IML release with neurolysis seems to have a higher risk of symptom recurrence than interdigital neurectomy. No patient-specific factors were identified as being associated with symptom recurrence. However, patients who did experience symptom recurrence in either surgical group had similar rates of revision surgery, which may be due to mild recurrent symptom severity in the IML release group that does not warrant revision surgery in these patients. Future studies should consider objective symptom recurrence severity and patient satisfaction.

LEVEL OF EVIDENCE

Level III.

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.

Safety and Efficacy of Percutaneous Morton Neuroma Cryoneurolysis Under Ultrasound Guidance

PURPOSE

To assess the technical success, safety and early efficacy of Morton neuroma (MN) cryoneurolysis.

MATERIALS AND METHODS

Retrospective review of 54 consecutive patients with MN treated with cryoneurolysis after failure of conservative treatment, from September 2022 to June 2023. Outcomes measurements included technical success (defined a successful ultrasound-guided placement of the cryoprobe), procedural safety according to Cirse classification and change in 6 months post-procedure by pain numeric rating scale (pNRS).

RESULTS

A total of 59 MN were treated during 55 procedures. Mean procedure duration was 47 min, all patients were discharged 2 h after the intervention. Technical success was 98.1%. No Cirse grade 3, 4 or 5 complication was reported. Three grade 2 complication occurred, including two chilblain-type lesions and one bone insufficiency fracture. At 6 months post-procedure, pNRS score was significantly decreased (2.7 ± 2.2 vs 7.1 ± 1.1) (p < 0.0001), with a mean score decrease of 4.1points. Thirty-two patients (60.4%) reported a complete pain relief, 15 (28.3%) a partial pain relief and 6 (11.3%) no pain relief, or increased pain.

CONCLUSION

Cryoneurolysis seems to be safe for the treatment of Morton neuroma. Six-month pain relief is promising and needs to be confirmed at long term.

Sonographic anatomy and technique to image the plantar digital nerves and aid identification of a Morton's neuroma

Introduction

The anatomy of the forefoot is complex, and the sonographic assessment to image the plantar digital nerves and exclude, diagnose or discriminate between a Morton's neuroma and intermetatarsal bursitis can be challenging.

Topic description and discussion

A good appreciation of the sonographic anatomy, technique, normal and abnormal appearances is required to undertake a sonographic assessment of the forefoot and its interspaces, particularly the plantar digital nerves. This is unpacked in this paper with associated pictorial aids. Muscles, tendons, and ligaments of the interspaces and the nearby metatarsophalangeal joints and their associated soft-tissue structures are helpful sonographic landmarks to guide imaging and assessment of the common and proper plantar digital nerves and the intermetatarsal bursa. These need to be appreciated from both dorsal and plantar sonographic approaches, in both short- and long-axis imaging planes.

Conclusion

Improved understanding of the anatomy and sonographic appearances of the interspace structures can enhance the sonographic assessment of the forefoot and improve diagnosis of a Morton's neuroma and/or intermetatarsal bursitis when present to guide patient management.

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.

Revision Surgery for Recurrent Morton Neuroma with Use of a Collagen Conduit

Background

Painful neuromas of the foot and ankle frequently pose a treatment dilemma because of persistent pain or recurrence after resection. Primary surgical treatment of painful neuromas includes simple excision with retraction of the residual nerve ending to a less vulnerable location1-4. The use of a collagen conduit for recurrent neuromas is advantageous, particularly in areas with minimal soft-tissue coverage options, and is a technique that has shown 85% patient satisfaction regarding surgical outcomes7. Additionally, the use of a collagen conduit limits the need for deep soft-tissue dissection and reduces the morbidity typically associated with nerve burial.

Description

Specific steps include appropriate physical examination, preoperative planning, and supine patient positioning. The patient is placed supine with a lower-extremity bolster under the ipsilateral extremity in order to allow improved visualization of the plantar surface of the foot. A nonsterile tourniquet is placed on the thigh. The incision site is marked out, and a longitudinal plantar incision is made until proximal healthy nerve is identified-typically approximately 1 to 2 cm, but the incision can be extended up to 6 cm. The incision is made between the metatarsals, with blunt dissection carried down to the neuroma. The neuroma is sharply excised distally through healthy nerve, and a whip stitch is placed to facilitate the collagen conduit placement. The collagen conduit is passed dorsally into the intermetatarsal space and secured to the dorsal fascia of the foot. The wound is closed with 3-0 nylon horizontal mattress sutures. Postoperatively, a soft dressing is applied to the operative extremity, and patients are advised to be non-weight-bearing for two weeks. At two weeks, patients begin partial weight-bearing with use of a boot, and physical therapy is initiated. No antibiotics are necessary, and 300 mg of gabapentin is prescribed and tapered off by the six-week follow-up visit. Follow-ups are conducted at 2, 6, 12, 24, and fifty-two weeks. It is necessary to monitor for signs and symptoms of infection, surgical complications, and neuroma recurrence during follow-up appointments.

Alternatives

Simple excision of the neuroma with proximal burial into muscle or bone is a common surgical technique. However, inadequate resection of the nerve or poor surgical technique can lead to recurrent neuromas. For neuromas not responding to simple excision, other techniques have been utilized, including cauterization, chemical agents, nerve capping, and muscle or bone burial5,6. The results of these techniques have varied, and none has gained clinical superiority over the other6.

Rationale

A study analyzing the use of collagen conduits for painful neuromas of the foot and ankle has shown this technique to be a safe and successful alternative to the previously discussed methods of resection7. That study by Gould et al. found that 85% of patients had a substantial reduction in pain, with mean visual analog scale (VAS) pain scores reducing from 8 to 10 preoperatively to 0 to 4 postoperatively7. Moreover, alternative biological conduits, such as the greater saphenous vein, have proven to be costly in time and resources, as this structure is often utilized in cardiovascular bypass surgery and its harvest conveys a risk of iatrogenic nerve injury to the patient7.Numerous studies focusing on excision of recurrent Morton neuromas via a plantar approach have found variable success rates. Of the patients surveyed in those studies, 75% reported substantial pain improvement. However, <50% of these queried patients reported complete pain relief8,9. Studies analyzing the dorsal approach for revision Morton neuroma excision found similar success rates. Approximately 78% of patients reported good or excellent postoperative outcomes, and significant improvements were observed in patient postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores for pain interference, intensity, and global physical health10,11. One study comparing outcomes following plantar versus dorsal approaches for recurrent Morton neuroma found no significant difference in postoperative patient outcomes. That study suggested that surgeons utilize the approach with which they are most comfortable12. Gould et al. reported an 85% success rate with collagen conduit, which was similar to if not slightly improved compared with the other prior studies. The utilization of a collagen conduit technique thus offers comparable patient outcomes for patients with difficult neuromas7.

Expected Outcomes

Recurrent neuroma resection with the use of a collagen conduit has proven to provide satisfactory patient outcomes regarding pain and neuritis symptoms7. The goal of any neuroma resection is to greatly diminish or entirely eliminate nerve pain. Based on the available evidence, there has been no proven clinical superiority of any particular technique over the others6. However, in the present example case, the location of the patient's neuroma in this video makes it 85% likely that the patient will report satisfactory outcomes and 50% likely that the patient will be entirely symptom-free7. At two weeks postoperatively, the patient reported well controlled pain, absence of burning or tingling sensation, full range of movement in the foot, and intact sensation throughout all major nerve distributions, including the saphenous; superficial peroneal nerve; deep peroneal nerve; and sural, medial, and lateral plantar nerves. However, sensation is absent distal to the site of a neuroma resection.

Important Tips

Careful preoperative planting is of utmost importance.Ruling out other potential pathologies is necessary to ensure proper outcomes.Meticulous dissection should be carried out, with delicate handling of the proximal nerve ending.Excision of the nerve should be done sharply through the healthy portion of the nerve.Appropriate sizing of the nerve conduit (with a commercially available industry sizer) should be performed.The nerve conduit should be passed dorsally and secured to the dorsal fascia without any tension.

Acronyms and Abbreviations

MRI = magnetic resonance imagingUS = ultrasoundVAS = visual analog scale.

Comparing Clinical Examination and Radiological Evaluation in the Preoperative Diagnosis and Location of Symptomatic Interdigital (Morton's) Neuroma

This study investigates whether clinical examination is as sensitive as ultrasound and magnetic resonance imaging (MRI) in the diagnosis and localization of symptomatic interdigital neuroma. A retrospective cohort study was conducted at two tertiary centers on all consecutive patients who underwent excision by a single foot and ankle specialist surgeon for a presumed interdigital neuroma between January 2008 and December 2020. Investigators collected preoperative clinical findings, radiological investigations, and postoperative outcomes. Sensitivity and positive predictive values were calculated and Z-score for 2 populations proportions was performed. One hundred fourteen consecutive patients were operated on for 131 suspected interdigital neuroma. Thirteen patients were excluded due to lack of adequate clinical documentation. Of the remaining 101 patients with 118 suspected interdigital neuroma, 115 were confirmed histologically (97.5%). The sensitivity of clinical assessment to accurately diagnose and place an interdigital neuroma in the correct space was calculated as 96.5%. The most common preoperative clinical feature was pain (99.2%). The calculated sensitivity for ultrasound to accurately diagnose an interdigital neuroma was 83.6%, and to correctly locate neuroma was 79.5% respectively, which were both statistically different compared to clinical assessment (p value: <.001 and p value: <.001). The calculated sensitivity for MRI to accurately diagnose an interdigital neuroma was 93.6%, which was statistically different to clinical assessment (p value: .005). Preoperative clinical assessment has the highest sensitivity to accurately diagnose interdigital neuroma when compared to MRI and ultrasound. Preoperative clinical assessment has higher sensitivity to accurately locate interdigital neuroma when compared to ultrasound.

Anatomy of the Plantar Intermetatarsal Tunnel: A Cadaveric Study

The contents of the plantar intermetatarsal tunnel (PIMT) and the relationship between the common plantar interdigital nerve (CPIN) and the PIMT were recorded. The width of the PIMT was measured at the metatarsal neck (MTN), metatarsophalangeal (MTP) joint and the base of the proximal phalanx (BPP). The length of the deep transverse metatarsal ligament (DTML), the PIMT and the intracapsular ligament (ICL) were also measured. The PIMT was revealed to be a narrow osseofibrous tunnel divided into 3 segments by the DTML: the distal section, the area under the DTML (middle) and the proximal section. The length of the middle section was 12.77 mm in the second intermetatarsal (IM) space and 10.18 mm in the third IM space. The lengths of the distal sections were 15.52 and 14.95 mm in the second and third IM spaces, respectively. There was some soft tissue between the CPIN and PIMT, and the CPIN was observed not to glide freely within the tunnel. The widths of the PIMT at the MTN, MTP joint and BPP were respectively 2.87, 2.56, and 3.42 mm in the second IM space and 3.10, 2.68 and 3.61 mm in the third IM space. The ICL lies between the capsules of the MTP joint, and the length of the ICL was 2.76 and 3.03 mm in the second and third IM spaces, respectively. The PIMT was found to be a complex spatial structure, and the ICL might prevent the CPIN from being squeezed into the IM space.

A Method for Entubulating Exposed Nerve Ends Following Neurectomy Using a Porcine Extracellular Matrix Nerve Cap

Compression and irritation at the plantar aspect of the transverse intermetatarsal ligament may lead to a compressive neuropathy called Morton's neuroma. There are many treatment options for Morton's neuroma, with the most common surgical option being traction neurectomy. While there has been success in many surgical procedures, up to 35% of patients treated with traction neurectomy have recurrent pain and up to one-third of these patients have a recurrent stump neuroma. These neuromas are caused by abnormal axonal growth during regeneration, leading to an unorganized mass of fibrotic collagenous tissues, Schwann cells, and axons. More recent surgical treatments of neuromas have included nerve capping, which has been proposed to prevent painful neuroma formation by isolating the nerve end from external chemosignaling and reducing disorganized axonal outgrowth. An off-the-shelf, biocompatible porcine small intestine submucosa (pSIS) derived nerve cap with internal chambering has been investigated in a rodent study, which showed less pain sensitivity and less axonal swirling indicative of reduced likelihood of neuroma formation. Furthermore, a recent clinical study indicated that patients experienced a significant reduction in pain 3 months after Morton's neuroma excision followed by repair using a nerve cap. This article describes the surgical technique of the aforementioned clinical study to mitigate neuroma formation, where a Morton's neuroma is excised, and the remaining proximal nerve stump is inserted within a nerve cap and buried in the surrounding muscle.Level of Evidence: Level V: Expert opinion.

Treatment of Morton's neuroma with minimally invasive distal metatarsal metaphyseal osteotomy (DMMO) and percutaneous release of the deep transverse metatarsal ligament (DTML): a case series with minimum two-year follow-up

BACKGROUND

The optimal treatment of symptomatic Morton's neuroma remains unclear; conservative methods are sometimes ineffective and neurectomy has significant rates of patient dissatisfaction. The aim of this study was to evaluate the outcome of minimally invasive distal metatarsal metaphyseal osteotomy (DMMO) and percutaneous release of the deep transverse metatarsal ligament (DTML) in patients with Morton's neuroma.

METHODS

Between January 2018 and November 2019, 27 patients (29 feet) diagnosed with Morton's neuroma after clinical and radiological evaluation underwent DMMO and percutaneous DTML release. The primary clinical outcomes were pain (VAS) and function (AOFAS score). Secondary outcomes included patient satisfaction, complications, and radiographic outcomes. Patients were followed up for a minimum of two years.

RESULTS

The median age of the participants was 66 years (range 48-79) and the follow-up time was 28 months (24-47). There was a decrease of 5.7 points in the VAS for pain (p < .001) and an increase of 19.9 in AOFAS (p < .001) after the surgical procedure. There was one case of superficial infection and one patient required resection of the neuroma (neurectomy). The majority of patients (89.7%) were satisfied and considered the procedure outcome as excellent or good.

CONCLUSION

Treatment of Morton's neuroma with minimally invasive distal metatarsal metaphyseal osteotomy and percutaneous release of the deep transverse metatarsal ligament showed significant improvement in pain and function with a low incidence of complications and a high rate of personal satisfaction.

Longitudinal Plantar Approach for Excision of Morton's Neuroma: Long-Term Results

Longitudinal plantar approaches are generally considered at risk for wound healing problems. Thus, we wanted to investigate long-term outcomes after a primary Morton's neuroma excision through a longitudinal plantar approach. A retrospective study of patients with primary neuroma excision was conducted. Twenty-four patients (28 feet) were evaluated at a mean 9-year follow-up (range, 6-14) by a single trained examiner using a specific postoperative evaluation protocol, including AOFAS Forefoot subjective and objective scores. Good-to-excellent outcomes were reported in 25 (89.3%) cases. A hypertrophic scar formation and keratosis occurred in only 2 cases (7.1%). All the patients, with a single exception, achieved full weightbearing with a postoperative shoe from the first day after the operation. A longitudinal plantar approach can lead to long-term, good-to-excellent outcomes with no case of recurrence or reoperation. Accurate wound closure and immediate weightbearing with a postoperative shoe can minimize the rate of complications. This approach should be considered for primary resection of Morton's neuromas.

Intermetatarsal ligament section assisted with sonography for the percutaneous surgery of Morton's disease: Cadaveric study

BACKGROUND

Surgical treatment of Morton's neuroma remains controversial. Several surgical techniques have been described including percutaneous transection of the deep metatarsal transverse ligament (DMTL).

PURPOSE

To evaluate the efficacy and safety of percutaneous release of the DMTL under ultrasound guidance for the treatment of Morton's syndrome.

MATERIALS AND METHODOLOGY

Percutaneous release of the DMTL was performed with ultrasound guidance in 48 intermetatarsal spaces of 16 cadaveric specimens. Specimens were then dissected to assess the completion of the release and the presence of any injuries of the neurovascular and tendinous adjacent structures.

RESULTS

The DMTL was visualized with ultrasound in all cases. Complete release of the ligament was achieved in 87.5% (42/48) cases. One case of interdigital nerve injury was found.

CONCLUSION

Percutaneous release of DMTL with ultrasound guidance for the treatment of Morton's disease has an acceptable rate of complications but care must be taken to ensure the complete release of the ligament.

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.

Microsurgical Neurectomy for Morton’s Neuroma

Introduction  “Morton’s neuroma” is one of the common causes of forefoot pain. If conservative therapy fails, surgical treatment should be performed. Microscopy is often used to operate on the digital nerve in the hand. However, to our knowledge, there has only been one report on the use of microsurgical technique. In this study, we describe a new microsurgical technique for Morton’s neuroma and discuss the advantages of this procedure.

Materials and Methods  Ten patients with Morton’s neuroma underwent surgical neurolysis or neurectomy using microsurgical technique. All patients were females with a mean age of 53 years (range = 35–65). The average follow-up time after surgery was 18 months (range = 6–24 months).

Results  Four cases initially underwent microsurgical neurolysis, but the patient’s symptoms did not improve. Two of these cases were then referred for revision surgery by microsurgical neurectomy. Following neurectomy, the mean preoperative pain and functional score improved significantly. In five cases, histopathology showed the neuroma was surrounded by metatarsal bursitis. In three cases, the nerve was sutured because each stump was easily reached.

Conclusion  Microsurgical technique allows careful visualization of the plantar digital nerve even through a dorsal approach. Separation of the digital nerve from the adhesive fibrous tissue can be performed quite readily under the microscope and Morton’s neuroma can then be completely removed en block. In some cases, microsurgical nerve repair may also be possible. A microsurgical approach is a reliable and useful tool for neurectomy of Morton’s neuroma.

Long-term results of dorsal neuroma/nerve transposition in the surgical management of Morton's neuroma and correlation with intraoperative anatomical variations

Background

Morton's neuroma (MN) is a common cause of forefoot pain. After failure of conservative management, surgical procedures include neurectomy or neuroma preserving procedures; resection of deep transverse intermetatarsal ligament only (DTIML), dorsal neurolysis, dorsal nerve transposition (DNT).

Objectives

This retrospective study evaluates the long-term results of open DNT, and it also reports anatomical variants in the plantar interdigital nerve.

Material and methods

The study included 39 patients (30 females and 9 males) who were treated for MN between 2002 and 2016.

Results

The mean pre-operative Giannini score of 13 (0–30) improved to 61 (20–80) (p < .0001), with only 6 patients scoring less than 50 (poor). Using Coughlin’s criterion for overall satisfaction, 9 patients (23%) reported excellent, 18 patients (46%) good, 6 patients (15%) fair and 6 patients (15%) reported poor results. In the long term, 25 patients (64%) had no pain, 8 patients (20%) had mild pain, and 6 patients (16%) had severe pain. Ten patients (26%) reported normal sensitivity in their toes, 26 patients (66%) had numbness, and 3 patients (8%) reported dysesthesia in their toes. Twenty-two patients (56%) could wear fashionable shoes, 11 patients (28%) comfortable shoes, and 6 patients (16%) modified shoes. Regarding walking distance, 30 patients (77%) had no limitation, and 9 patients (23%) reported some limitation. Nineteen per cent regretted having surgery. Around 40% (17 out of 43 web spaces) showed anatomical variations in either the nerve or in the web space and we could not identify any specific risk factors in relation to the outcome.

Conclusion

Dividing the DTIML or dorsal neurolysis should be considered as the primary surgical treatment and, if this fails, neurectomy would be an option. DNT can be considered if one is concerned about stump neuroma, but this may be technically demanding and in some patients it may not be possible.

Level of Evidence: Level IV - Case Control Retrospective study.

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.

The interphalangeal angle as a novel radiological measurement tool for Morton's neuroma - a matched case-control study

BACKGROUND

The aim of this retrospective study was to examine if a correlation between Morton's Neuroma (MN) and an increased interphalangeal angle (IPA) or intermetatarsal angle (IMA) can be found in preoperative weightbearing dorsal-plantar X-rays of the foot.

METHODS

Forty-five patients with forty-nine MN in the interspaces 2/3 or 3/4 and 49 controls were recruited for this study. Every MN was matched with an asymptomatic control without history of metatarsalgia. The diagnosis was made by clinical examination, magnetic resonance imaging (MRI) and positive histopathology after operative resection. IMA 1/5, 2/3, 2/4, 2/5, 3/4 and IPA 2/3, 3/4 were measured for both groups.

RESULTS

The IPA 3/4 was significantly enlarged by 2.8 degrees (p < 0.001) with Area under the curve (AUC) 0.75 (p < 0.001), sensitivity of 73% and specificity of 67% in feet with MN compared to controls. The IMA 3/4 was significantly enlarged by 1 degree (p < 0.048) with AUC 0.64 (p < 0.031), sensitivity of 71% and specificity of 43% in feet with MN compared to controls. No difference between IMA 2/4, 2/5, 1/5 or correlation between IPA or IMA and the size of the MN in the MRI was found.

CONCLUSION

The results confirm the clinical observation of an increased IPA in patients with MN. An increased IPA should therefore be considered in the diagnosis of MN.

A problem-based approach in musculoskeletal ultrasonography: central metatarsalgia

Ultrasonography (US) is a useful diagnostic method that can be easily applied to identify the cause of metatarsalgia. The superficial location of structures in the foot, dynamic capability of US, and the ability to perform direct real-time evaluations of the pain site are also strong advantages of US as a modality for examining the foot. Moreover, knowing the possible pain sources to investigate when a patient has a specific site of pain will enhance the diagnostic quality of US, and will help radiologists to perform US efficiently and effectively. The purpose of this article is to review the common etiologies of metatarsalgia including Morton’s neuroma, plantar plate injury, synovitis, tenosynovitis, bursitis, and metatarsal fractures, and to discuss their US features.

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.

Clinico-radiological review of peripheral entrapment neuropathies - Part 2 Lower limb

PURPOSE

This review discusses the relevant anatomy, etiopathogenesis, current notions in clinical and imaging features as well as management outline of lower limb entrapment neuropathies.

METHODS

The review is based on critical analysis of the current literature as well as our experience in dealing with entrapment neuropathies of the lower limb.

RESULTS

The complex anatomical network of nerves supplying the lower extremities are prone to entrapment by a heterogenous group of etiologies. This leads to diverse clinical manifestations making them difficult to diagnose with traditional methods such as clinical examination and electrodiagnostic studies. Moreover, some of these may mimic other common conditions such as disc pain or fibromyalgia leading to delay in diagnosis and increasing morbidity. Addition of imaging improves the diagnostic accuracy and also help in correct treatment of these entities. Magnetic resonance imaging is very useful for deeply situated nerves in pelvis and thigh while ultrasound is well validated for superficial entrapment neuropathies.

CONCLUSION

The rapidly changing concepts in these conditions accompanied by the advances in imaging has made it essential for a clinical radiologist to be well-informed with the current best practices.

First webspace Morton's neuroma case report with literature review

Morton's neuromas are benign lesions of the inter-digital nerves within the foot. They are most commonly found in the second and third webspace. Morton's neuroma of the first webspace is very rare. A case of a 42-year-old female who presented complaining of long standing forefoot pain is presented. The patient was diagnosed with a soft tissue tumor in the 1st webspace. An excisional biopsy of the tumour confirmed a Morton's neuroma. Very few cases of Morton's neuroma in the first webspace have been reported in the literature.

Ultrasound-Guided Decompression of the Intermetatarsal Nerve for Morton's Neuroma: A Novel Closed Surgical Technique

BACKGROUND

This study describes the technique for decompression of the intermetatarsal nerve in Morton's neuroma by ultrasound-guided surgical resection of the transverse intermetatarsal ligament. This technique is based on the premise that Morton's neuroma is primarily a nerve entrapment disease. As with other ultrasound-guided procedures, we believe that this technique is less traumatic, allowing earlier return to normal activity, with less patient discomfort than with traditional surgical techniques.

METHODS

We performed a pilot study on 20 cadavers to ensure that the technique was safe and effective. No neurovascular damage was observed in any of the specimens. In the second phase, ultrasound-guided release of the transverse intermetatarsal ligament was performed on 56 patients through one small (1- to 2-mm) portal using local anesthesia and outpatient surgery.

RESULTS

Of the 56 participants, 54 showed significant improvement and two did not improve, requiring further surgery (neurectomy). The postoperative wound was very small (1-2 mm). There were no cases of anesthesia of the interdigital space, and there were no infections.

CONCLUSIONS

The ultrasound-guided decompression of intermetatarsal nerve technique for Morton's neuroma by releasing the transverse intermetatarsal ligament is a safe, simple method with minimal morbidity, rapid recovery, and potential advantages over other surgical techniques. Surgical complications are minimal, but it is essential to establish a good indication because other biomechanical alterations to the foot can influence the functional outcome.

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)

Improved Injection Technique of Ethanol for Morton's Neuroma

BACKGROUND

Morton's neuroma is a common cause of forefoot pain. Various conservative methods (injections of various pharmacologic agents) have been published with an outcome of 6%-75% success rate (free of pain in daily life) per injection. The aim of the present study was to assess the outcome of an improved localization technique, a higher dosage, and a higher percentage of ethanol.

METHODS

Using fluoroscopic and electroneurographic guidance, 2.5 mL of 70% ethanol were injected into 33 feet with a magnetic resonance imaging (MRI)-verified neuroma. We evaluated patients at up to 5-year follow-up.

RESULTS

A "success rate" of more than 82% per single injection (defined as free of pain in daily life) was achieved and no recurrence was seen over 5 years. All scores (visual analog scale; Short Form-36 subscales, American Orthopaedic Foot & Ankle Society ankle-hindfoot score) showed significant improvement (P < .0001). Mean 1.2 injections were necessary. No significant side effects were seen. However, some mild pain persisted in some patients who participated in sports.

CONCLUSION

The injection of 2.5 mL of 70% ethanol under fluoroscopic and electroneurographic guidance was a safe method for the treatment of MRI-verified Morton's neuromas. Combining the effect of a higher percentage of alcohol and a higher dosage and an improved localization technique resulted in a high rate of patients without pain.

LEVEL OF EVIDENCE

Level IV, cases series, prospective.

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.

Nerve decompression according to A.L. Dellon in Morton's neuroma - A retrospective analysis

BACKGROUND

First reported by Dellon et al. in 1992, nerve decompression by dissecting the deep transversal intermetatarsal ligament through a dorsal incision appears to be a reliable method for treating Morton's neuroma by addressing its underlying pathomechanism, since it should rather be considered as Morton's entrapment. As there are no current studies dealing with Dellon's surgical technique, we carried out a retrospective analysis with the aim of showing that nerve decompression is an effective method to treat Morton's neuroma, and one that considers its true pathology.

MATERIALS AND METHODS

All patients with a clinical diagnosis of Morton's neuroma, verified by MRI and treated by nerve decompression were included in this study in the years from 2010 to 2018 at our department. Follow-up was performed at least six months post-intervention; pain and function history were ascertained using the VAS (visual analogue scale) score and the German foot function index. Skin sensitivity testing was performed using Semmes-Weinstein monofilaments.

RESULTS

A total of 12 patients were treated and followed-up during the study period. Postoperatively, there was significant improvement in the values of the VAS score both under strain (p-value: 0.0021) and at rest (p-value: 0.0062), as well as in the foot function index (p-value: 0.0022). There was no significant difference in skin sensitivity of the innervation areas of the interdigital nerves of the affected foot compared with the healthy reference foot (p-value: 0.0968).

CONCLUSION

Dellon's decompression method yielded a highly positive outcome, and based on our findings, we consider it a reliable, technically simple and promising approach to treat Morton's neuroma. It is a minimally invasive technique that addresses the pathomechanism of peripheral nerve entrapment and has a low rate of complication as well as rapid patient recovery.

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.

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.

Forefoot disorders and conservative treatment

Forefoot disorders are often seen in clinical practice. Forefoot deformity and pain can deteriorate gait function and decrease quality of life. This review presents common forefoot disorders and conservative treatment using an insole or orthosis. Metatarsalgia is a painful foot condition affecting the metatarsal (MT) region of the foot. A MT pad, MT bar, or forefoot cushion can be used to alleviate MT pain. Hallux valgus is a deformity characterized by medial deviation of the first MT and lateral deviation of the hallux. A toe spreader, valgus splint, and bunion shield are commonly applied to patients with hallux valgus. Hallux limitus and hallux rigidus refer to painful limitations of dorsiflexion of the first metatarsophalangeal joint. A kinetic wedge foot orthosis or rocker sole can help relieve symptoms from hallux limitus or rigidus. Hammer, claw, and mallet toes are sagittal plane deformities of the lesser toes. Toe sleeve or padding can be applied over high-pressure areas in the proximal or distal interphalangeal joints or under the MT heads. An MT off-loading insole can also be used to alleviate symptoms following lesser toe deformities. Morton's neuroma is a benign neuroma of an intermetatarsal plantar nerve that leads to a painful condition affecting the MT area. The MT bar, the plantar pad, or a more cushioned insole would be useful. In addition, patients with any of the above various forefoot disorders should avoid tight-fitting or high-heeled shoes. Applying an insole or orthosis and wearing proper shoes can be beneficial for managing forefoot disorders.

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.

Peripheral nerve injuries in the pediatric population: a review of the literature. Part III: peripheral nerve tumors in children

INTRODUCTION

Peripheral nerve tumors type, inciedence and treatment in the pediatric population should be analyzed.

METHODS

We have performed an extense literature review of this subject.

RESULTS

incidence and distribution are similar to those observed in adults. The most common peripheral nerve tumors in children are neurofibromas and schwannomas. Malignant peripheral nerve sheath tumors are also observed, specially associated with genetic syndromes, like neurofibromatosis and Carney complex.

CONCLUSION

In this review, peripheral nerve tumors have been divided into three categories to aid with understanding: reactive and hyperplastic lesions, benign tumors, and malignant tumors. The most frequent lesions have been described.

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.

Treatment of Morton's neuroma: A systematic review

BACKGROUND

The treatment of Morton's neuroma (MN) can be operative, conservative and infiltrative. Our aim was the evaluation of evidence on outcomes with different types of conservative, infiltrative and surgical treatment in patients affected by primary MN.

METHODS

The bibliographic search was conducted in MEDLINE, Cochrane Library, DARE. Only studies in English were collected. The last search was in August 2015. Case series and randomized controlled trials (RCTs) assessing patients' satisfaction or pain improvement at an average follow-up of at least 6 months after treatment of primary MN were included. Two reviewers selected the studies, evaluated their methodological quality, and retrieved data independently.

RESULTS

Of 283 titles found, only 29 met the inclusion criteria. Data showed better outcomes with operative treatment.

CONCLUSIONS

The evaluated case series and few RCTs showed better results with invasive treatment. More and better RCTs which evaluate risk-benefit ratio are required to confirm these results.

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.

Morton's interdigital neuroma of the foot: A literature review

Morton's neuroma is one of the most common causes of metatarsalgia. Despite this, it remains little studied, as the diagnosis is clinical with no reliable instrumental diagnostics, and each study may deal with incorrect diagnosis or inappropriate treatment, which are difficult to verify. The present literature review crosses all key points, from diagnosis to surgical and nonoperative treatment, and recurrences. Nonoperative treatment is successful in a limited percentage of cases, but it can be adequate in those who want to delay or avoid surgery. Dorsal or plantar approaches were described for surgical treatment, both with strengths and weaknesses that will be scanned. Failures are related to wrong diagnosis, wrong interspace, failure to divide the transverse metatarsal ligament, too distal resection of common plantar digital nerve, an association of tarsal tunnel syndrome and incomplete removal. A deep knowledge of the causes and presentation of failures is needed to surgically face recurrences.

Ultrasound-Guided Hyaluronic Acid Injection for the Management of Morton's Neuroma

BACKGROUND

Morton's neuroma is one of the common causes of forefoot pain. In the present study, hyaluronic acid injection was performed on patients to determine the efficacy and adverse effects of hyaluronic acid in management of Morton's neuroma.

METHODS

Eighty-three patients with Morton's neuroma in their third intermetatarsal space with definite Mulder's click were included in the study. Those with severe forefoot deformities such as forefoot cavus or hallux valgus on plain X-rays were excluded. Ultrasound-guided hyaluronic acid injections were performed on all patients weekly for 3 weeks. Pain during walking using visual analogue scale (VAS) and AOFAS Forefoot Scale were prospectively evaluated preinjection, and at 2, 4, 6, 12 months postinjection.

RESULTS

Significant improvement in VAS and AOFAS Forefoot Scale were seen overall at 2 months after hyaluronic acid injections ( P < .05). Then, there were almost no changes after 4 months, continuing until 12 months. The mean VAS was decreased from 73.1 initially to 23.0 at 12 months and AOFAS Forefoot Scale was increased from 32.2 to 86.5. There were no complications which occurred.

CONCLUSION

In the present study, ultrasound-guided hyaluronic injection was clinically effective for pain relief and functional improvement for at least 12 months in patients with Morton's neuroma. However, numbness associated with Morton's neuroma should be addressed more cautiously since it may persist without much improvement.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Outcomes following excision of Morton's interdigital neuroma: a prospective study

AIMS

This is the first prospective study to report the pre- and post-operative patient reported outcomes and satisfaction scores following excision of interdigital Morton's neuroma.

PATIENTS AND METHODS

Between May 2006 and April 2013, we prospectively studied 99 consecutive patients (111 feet) who were to undergo excision of a Morton's neuroma. There were 78 women and 21 men with a mean age at the time of surgery of 56 years (22 to 78). Patients completed the Manchester-Oxford Foot Questionnaire (MOXFQ), Short Form-12 (SF-12) and a supplementary patient satisfaction survey three months pre-operatively and six months post-operatively.

RESULTS

Statistically significant differences were found between the mean pre- and post-operative MOXFQ and the physical component of the SF-12 scores (p = 0.00081 and p = 0.00092 respectively). Most patients reported their overall satisfaction as excellent (n = 49, 49.5%) or good (n = 29, 29.3%), but ten patients were dissatisfied, reporting poor (n = 8, 8.1%) or very poor (n = 2, 2.0%) results. Only 63 patients (63%) were pain-free at follow-up: in eight patients (8.1%), the MOXFQ score worsened. There was no statistically significant difference in outcome between surgery on single or multiple sites. However, the MOXFQ scores were significantly worse after revision surgery (p = 0.004).

CONCLUSIONS

The patient-reported outcomes after resection of a symptomatic Morton's neuroma are acceptable but may not be as good as earlier studies suggest. Surgery at several sites can be undertaken safely but caution should be exercised when considering revision surgery. Cite this article: Bone Joint J 2016;98-B:1376-81.

Efficacy of Foot and Ankle Corticosteroid Injections

BACKGROUND

Corticosteroid injections have been used for a variety of foot and ankle pathologies over the years, and our aim was to evaluate the efficacy and safety of them in our clinic.

MATERIALS AND METHODS

We performed a retrospective review of notes and a telephone questionnaire on the clinical outcome of all patients who underwent a corticosteroid injection of the foot or ankle in a year. All procedures were performed in an outpatient setting by a consultant musculoskeletal radiologist using either ultrasound or X-ray guidance and had a minimum of 2 years of follow-up.

RESULTS

Overall, 314 of 365 (86%) patients reported a significant improvement in symptoms, and 242 (66%) reported complete resolution of their pain, with 107 (29%) remaining asymptomatic at the 2-year follow-up. The mode time of recurrence of pain was 3 months. Fifty-one (14%) underwent a further injection and 88 (24%) underwent operative intervention within the follow-up period. Complication rates in our series were low. There were no reported infections. Complications occurred in 5 patients (1.3%), including steroid flare, pain, and plantar plate ruptures.

CONCLUSION

Corticosteroid injections were a safe and effective option for treating a variety of foot and ankle conditions and reduced the need for surgery. They were particularly effective for the treatment of ankle soft tissue impingement. They appear ineffective in providing significant improvement in pain for longer than 3 months in conditions such as plantar fasciitis and hallux rigidus.

LEVEL OF EVIDENCE

IV, case series.

Interdigital Neuroma in the Second Intermetatarsal Space Associated with Metatarsophalangeal Joint Instability

The entrapment theory is the most commonly accepted theory concerning the development of interdigital neuroma; it incriminates the deep transverse metatarsal ligament as the major causative factor of the condition. This report presents a patient with interdigital neuroma in the second intermetatarsal space, which was strongly suspected to be caused by the metatarsophalangeal joint instability due to plantar plate injury. Surgical intervention revealed that the neuroma was located more distally and dorsally than the deep transverse metatarsal ligament and was pinched between the adjacent metatarsal heads, suggesting the involvement of the metatarsophalangeal joint instability and chronic trauma as etiologies in this case.

Ultrasound Evaluation of Morton Neuroma Before and After Laser Therapy

OBJECTIVE

The objective of our study was to retrospectively assess for differences in imaging appearances of Morton neuromas before and after laser therapy using diagnostic ultrasound (US).

MATERIALS AND METHODS

A retrospective review was performed to identify patients who underwent US imaging to evaluate for Morton neuroma during the study period (June 1, 2013-July 1, 2014); of the 42 patients identified, 21 underwent US evaluations before and after laser therapy. US reports and images were reviewed and correlated with clinical history. The final study group consisted of 21 patients who had a total of 31 Morton neuromas evaluated using US after treatment. A retrospective review was then performed to characterize the appearances of these lesions before and after therapy followed by an analysis of variables.

RESULTS

Retrospective US review of 31 pretreatment Morton neuromas showed fusiform, heterogeneously hypoechoic masses with well-defined borders in most cases and that pain was reported when transducer pressure was applied in 97% (30/31) of cases. After treatment, lesions showed ill-defined borders (23/31), and pain with application of transducer pressure was either significantly decreased or absent (29/31); these findings were concordant with the clinical findings. Both of these characteristics were statistically significant (p < 0.0001). In addition, more Morton neuromas occurred in the second intermetatarsal space than in the third intermetatarsal space (p < 0.0001).

CONCLUSION

US may be used to identify posttreatment changes after laser therapy of Morton neuromas. Posttreatment changes include ill-defined borders and less pain or the absence of pain with the application of transducer pressure. These criteria may be applied in future clinical studies evaluating the efficacy of laser therapy for Morton neuroma.

Neurectomy for Bilateral Morton's Neuroma A Case Report of a Male Patient

Morton's neuroma is a common condition that mainly affects middle-aged women, and many articles have addressed the surgical treatment of this condition. Previous reports have described bilateral neuroma excision in women but not in men. We report a rare case of bilateral neuromas in a male patient treated with simultaneous neurectomy.

Percutaneous needling of Morton's complex: a technical note

BACKGROUND

the Morton's complex, i.e. fibrotic mass enfolding the medial plantar nerve, the bursa and the interdigital transverse ligament in the web space, is a common cause of pain and functional disability. Conservative and operative treatments are investigated but currently the best approach to treat the Morton's complex is unknown.

METHODS

we describe a non-invasive, straight forward intervention consisting on multiple percutaneous punctures, shearing the fibrotic tissue in lateromedial and anteroposterior directions. The goal is to break up fibrosis occupying the intermetatarsal space thus releasing the affected nerve from the adjacent structures, there by stimulating tissue remodelling.

RESULTS

slow tissue remodelling occurs following sequential fibrosis cleavage through multiple needling. Needling of the intermetatarsal fibrosis is performed every eight weeks until pain resolution. Echographic changes are associated to pain reduction as measured by Visual Analogue Score (VAS).

CONCLUSION

we present an original idea that may improve Morton's management. Upcoming prospective clinical studies have to demonstrate the symptomatic benefits and the usefulness of this novel echographic intervention.

[Metatarsalgia: Differential diagnosis and therapy]

Metatarsalgia refers to localized or generalized forefoot pain in the region of the metatarsal heads. Symptoms can be isolated or in combination with accompanying deformities occurring in the forefoot and/or hindfoot. Anamnesis and clinical investigation usually yield to the diagnosis, the underlying cause on the other hand is not always easy to identify. In the foreground of the treatment is the exhaustion of conservative forms of therapy to minimize the symptoms of local pressure increase and callus under the metatarsal heads. In addition, various surgical methods are available, such as corrective osteotomy of the metatarsale bone, soft tissue interventions and the correction of associated deformities. The indications for surgical intervention should be made with caution in order to avoid failures and complaints persisting after surgery. The most common problems are an inadequate indication for surgery, technical problems and insufficient postoperative treatment.

Simple Neurectomy Versus Neurectomy With Intramuscular Implantation for Interdigital Neuroma: A Comparative Study

BACKGROUND

Simple neurectomy is a standard treatment of interdigital nerve neuroma after failure of conservative treatment. Recently, neurectomy with intramuscular implantation of the proximal nerve stump has been proposed as a safe and effective alternative method providing significant pain improvement. However, there remains little evidence supporting one technique over the other. The purpose of this study was to compare functional outcomes and complications of simple neurectomy versus neurectomy with intramuscular implantation.

METHODS

Retrospective chart review along with prospectively collected data of 99 consecutive patients (105 feet with 118 neuromas) who were diagnosed with interdigital neuroma of the foot and underwent simple neurectomy (66 patients / 72 feet / 78 neuromas) and neurectomy with intramuscular implantation of proximal nerve stump into intrinsic muscle of foot (33 patients / 33 feet / 40 neuromas) between 2000 and 2013. The minimum follow-up to be included in the study was 6 months for both techniques (mean = 44.6 months, range = 6 to 150 months for simple neurectomy; and mean = 19.3 months, range = 6 to 66 months for neurectomy with intramuscular implantation of proximal nerve stump into the intrinsic muscle). The primary outcomes were Foot Function Index (FFI); pain, disability, activity limitation, and total score, Short Form-36 (SF-36: physical and mental component scores); and visual analog scale (VAS). Secondary outcomes included operative time and complications. Pre- and postoperative SF-36, and FFI, and pain (VAS) scores were obtained and compared using a paired t test. An independent t test was used to assess the functional outcomes and operative time between the 2 groups, and a chi-square test was used to compare the complications between the 2 techniques.

RESULTS

Both groups demonstrated significant improvement of postoperative functional outcomes (FFI, SF-36, and VAS; P < .001, all) compared to the preoperative period. Neurectomy with intramuscular implantation demonstrated significant improvement of pain compared to simple neurectomy as measured with VAS (P = .002); however, the operative time was significantly longer than the simple neurectomy technique (P = .001). The rest of the functional outcomes measured were comparable between the 2 techniques. Complications in both simple neurectomy and implantation techniques were persistent pain (11.5% vs. 2.5%, P = .07), revision rate (5.1% vs. 0.0%, P = .08), and painful scar (5.1% vs. 5.0%, P = .83), respectively, but it did not reach statistical significance (P > .05, all).

CONCLUSION

Both simple neurectomy and neurectomy with intramuscular implantation demonstrated significant improvement in terms of functional outcomes as measured with the FFI, SF-36, and VAS in patients with interdigital neuroma. Although requiring a longer operative time, neurectomy with intramuscular implantation technique might offer superior pain relief with comparable complications to the simple neurectomy technique.

The role of fasciae in Civinini-Morton's syndrome

This study evaluates the pathogenetic role of the perineural connective tissue and foot fasciae in Civinini-Morton's neuroma. Eleven feet (seven male, four female; mean age: 70.9 years) were dissected to analyse the anatomy of inter-metatarsal space, particularly the dorsal and plantar fasciae and metatarsal transverse ligament (DMTL). The macrosections were prepared for microscopic analysis. Ten Civinini-Morton neuromas obtained from surgery were also analysed. Magnetic resonance images (MRIs) from 40 patients and 29 controls were compared. Dissections showed that the width of the inter-metatarsal space is established by two fibrous structures: the dorsal foot fascia and the DMTL, which, together, connect the metatarsal bones and resist their splaying. Interosseous muscles spread out into the dorsal fascia of the foot, defining its basal tension. The common digital plantar nerve (CDPN) is encased in concentric layers of fibrous and loose connective tissue, continuous with the vascular sheath and deep foot fascia. Outside this sheath, fibroelastic septa, from DMTL to plantar fascia, and little fat lobules are present, further protecting the nerve against compressive stress. The MRI study revealed high inter-individual variability in the forefoot structures, although only the thickness of the dorsal fascia represented a statistically significant difference between cases and controls. It was hypothesized that alterations in foot support and altered biomechanics act on the interosseous muscles, increasing the stiffness of the dorsal fascia, particularly at the points where these muscles are inserted. Chronic rigidity of this fascia increases the stiffness of the inter-metatarsal space, leading to entrapment of the CDPN.

Carpal and cubital tunnel and other, rarer nerve compression syndromes

BACKGROUND

Carpal tunnel syndrome is by far the most common peripheral nerve compression syndrome, affecting approximately one in every six adults to a greater or lesser extent. Splitting the flexor retinaculum to treat carpal tunnel syndrome is the second most common specialized surgical procedure in Germany. Cubital tunnel syndrome is rarer by a factor of 13, and the other compression syndromes are rarer still.

METHODS

This review is based on publications retrieved by a selective literature search of PubMed and the Cochrane Library, along with current guidelines and the authors' clinical and scientific experience.

RESULTS

Randomized controlled trials have shown, with a high level of evidence, that the surgical treatment of carpal tunnel syndrome yields very good results regardless of the particular technique used, as long as the diagnosis and the indication for surgery are well established by the electrophysiologic and radiological findings and the operation is properly performed. The success rates of open surgery, and the single-portal and dual-portal endoscopic methods are 91.6%, 93.4% and 92.5%, respectively. When performed by experienced hands, all these procedures have complication rates below 1%. The surgical treatment of cubital tunnel syndrome has a comparably low complication rate, but worse results overall. Neuro-ultrasonography and magnetic resonance imaging (neuro-MRI) are increasingly being used to complement the diagnostic findings of electrophysiologic studies.

CONCLUSION

Evidence-based diagnostic methods and treatment recommendations are now available for the two most common peripheral nerve compression syndromes. Further controlled trials are needed for most of the rarer syndromes, especially the controversial ones.