The digital nerve stretch test: A sensitive indicator of Morton's neuroma and neuritis

We describe a physical sign not previously reported, which adds a sensitive and specific tool to assist the clinical diagnosis of interdigital neuralgia in the foot including Morton's entrapment neuropathy.A prospective record was kept of symptoms and signs in patients treated for Morton's neuroma or neuritis, including the web space pressure test, metatarsal approximation, Mulder's click and the digital nerve stretch test.Twenty-two consecutive patients underwent surgery for Morton's metatarsalgia. At surgery, 16 patients had a neuroma; four had an abnormally thickened, inflamed nerve, and one had evidence of neuritis, and underwent neurolysis. One patient had an epidermal cyst.Our digital nerve stretch test showed 100% sensitivity, with a 95% positive predictive value for Morton's neuroma and neuritis. However, it was also positive in the patient with an epidermal cyst.Although demonstrated in a small group, we believe this sign to be of value in the diagnosis of this condition, and worthy of further study and evaluation.     

Contribution of a new electrophysiologic test to Morton's neuroma diagnosis

BackgroundMorton's neuroma causes metatarsalgia due to the interdigital neuropathy. The small nerve diameter compromises their evaluation in image studies. To overcome this problem we propose a new electrophysiological test.MethodsWe conducted a prospective case–control study performing a orthodromic electroneurography using subdermal electrodes in controls and patients to assess the validity. Additionally all patients were tested with magnetic resonance. Some patients required surgery and subsequent histological evaluation.ResultsThe new ENG procedure showed higher sensitivity and specificity. Methodological standardization was easy and the test was well tolerated by the subjects.ConclusionsOur test demonstrated remarkable diagnostic efficiency, and also was able to identify symptomatic patients undetected by magnetic resonance, which underlines the lack of correlation between the size and intensity of the lesion. This new electrophysiological method appears to be a highly sensitivity, well-tolerated, simple and low-cost for Morton's neuroma diagnosis.     

Endoscopic Resection of a Toe Web Fibroma That Was Mimicking a Morton's Neuroma

Fibroma of tendon sheath is a rare benign tumor originating in the tendon or tendon sheath. It most commonly occurs in upper extremity and rarely presents in the foot. In this report, a case of fibroma of tendon sheath in the web space with Morton's neuroma-like symptoms was presented. The tumor was resected endoscopically with preservation of the interdigital nerve. Post-operatively, the symptoms were subsided and the toe sensation was preserved. There was no sign of recurrence of the tumor at the end of 3-year-period of follow-up.     

Hydrocortisone/local anaesthetic injection versus ultrasound in the diagnosis of interdigital neuroma

It is generally accepted that an interdigital neuroma (Morton's neuroma) is a clinical diagnosis. If the diagnosis is equivocal, other investigations such as ultrasound (US), MRI Scan, a local anaesthetic with or without hydrocortisone or electromyographic nerve conduction studies can be used.The aim of this retrospective study is to compare the accuracy of ultrasound versus a “cocktail” of hydrocortisone (HCI)/local anaesthetic injection (LAI), as an adjuvant investigation in the diagnosis of interdigital neuroma. The results showed that both these investigations are excellent in confirming an interdigital neuroma.     

Results after Morton's neuroma resection via plantar approach

PurposeThe purpose of the study is to present the results after resection of Morton's neuroma via the plantar approach.Materials and methodsIn total 415 consecutive patients were operated on Morton's neuroma. The average follow-up was 39 months (range: 9–94). The mean age at the time of surgery was 56 years (range: 28–86). In 217 cases the neuroma was located in 2nd–3rd and 256 cases in the 3rd–4th interdigital space. A 174 neuromas were seen at the left and 170 at the right foot; 64 cases were bilateral. A 356 patients could be followed-up with a VAS and modified Kitaoka-score. All patients were operated via a plantar approach.ResultsA 328 of the 356 patients were subjectively satisfied with the results. The most significant improvement was documented for pain relief during daily activity. The average Kitaoka-score at the follow-up was 72 points (range: 35–75). In 6 cases postoperatively superficial wound healing problems occurred which were treated conservatively. A 10 patients complained about the plantar scar, in 32 patients a shoe conflict was observed for less than 6 months.ConclusionSurgical resection of a Morton's neuroma via the plantar approach lead to good and reproducible results.     

Comparative Analysis of Dorsal Nerve Relocation versus Dorsal Neurectomy in the Surgical Management of Morton's Neuroma

This clinical study compares the use of dorsal nerve relocation (DNR; also known as dorsal nerve transfer) and dorsal neurectomy (DN) in the surgical management of Morton's neuroma within the surgical directorate of an NHS Hospital Trust (Princess Royal University Hospital) in the South East of England between 2002 and 2009. Approaches to the surgical management of Morton's neuroma are dependent on the views of individual surgeons, rather than empirical evidence and varied considerably, so this study was essentially all about checking whether best practice is being followed and making improvements. Data were collected using an in-depth review of patients’ case notes and patient questionnaires. In total, there were 47 cases (51 web spaces), 25 (28 web spaces) in the DNR group, and 22 (23 web spaces) in the DN group. The key indication for surgery in all cases reviewed was failure of the condition to improve using conservative methods. The mean follow-up duration was 36 months (12-89) in the DNR group and 41 months (12 69) in the DN group. Coughlin's criterion was used to analyze individual records. The results suggest that DNR is more effective (92%) than DN in the surgical management of Morton's neuroma (82%). Key advantages of DNR include earlier return to wearing routine footwear, earlier return to normal routine/work, and better resolution of sensory symptoms in the toes. Although DNR is a slightly longer procedure than DN, minor difficulties were encountered relating to nerve mobilization because of overlying prominent veins or multiple nerve branches rather than a single nerve. DNR avoids the risk of a stump neuroma formation. Our results, although supporting the literature, are not statistically significant. There are no direct comparative studies between DNR and DN in the literature, and therefore potential for more studies in the form of prospective randomized trials to establish a robust evidential basis for the surgical management of Morton's neuroma are needed.     

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

BackgroudThis 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.MethodsSeveral 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.ResultsWith 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.ConclusionsCorticosteroid 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.     

Minimally Invasive Intermetatarsal Nerve Decompression for Morton's Neuroma: A Review of 27 Cases

Minimally invasive nerve decompression for operative management of Morton's neuroma has been shown to be an effective alternative to neurectomy; however, little is known about postoperative outcomes. In this retrospective case series, we reviewed 27 procedures in 25 patients who underwent minimally invasive nerve decompression as primary surgical management for Morton's neuroma. Most subjects (22, or 88%) had 12 or more months of health plan enrollment postoperatively; 3 (12%) had 4 to 7 months of enrollment after the procedure. Postoperative patient satisfaction, complications and the need for a follow-up neurectomy were ascertained from medical record review. Additionally, demographic and clinical data were extracted from electronic sources. Patient satisfaction was unknown for 5 (18.5%) of the 27 procedures. Among the 22 (81.5%) procedures for which there were valid patient satisfaction data, patient satisfaction was excellent for 11 (50%); good for 2 (9.1%), and poor for 9 (40.9%). During the follow-up period, 5 (18.5%) patients required an open neurectomy. Among the 6 (22.2%) patients who presented without a Mulder's sign on physical exam preoperatively, 83% reported excellent results. Minimally invasive nerve decompression may not be as effective as previously seen; however, it may be indicated in patients presenting with absence of a Mulder's sign, a physically small or nascent neuroma.     

Morton's toe; a neuroma

Two cases of perineural fibroma are reported and the more recent literature has been reviewed. From the data of all these cases it is evident that Morton's metatarsalgia is not due to neuralgia but due to a perineural fibroma of the fourth digital nerve. It is a distinct clinical entity in itself and if the symptoms are severe, the growth should be removed surgically.     

Misdiagnosis of plexiform neurofibroma of the medial plantar nerve: Case report

Plexiform neurofibromas are benign tumors of the peripheral nerve. Diagnosis may be challenging, if they present mimicking other peripheral nerve pathologies.We report the case of a patient who had severe foot pain, which progressively hampered her walking ability, erroneously attributed to recurrent Morton's neuroma. Diagnosis of plexiform neurofibroma of her right medial plantar nerve was made 15 years after the appearance of symptoms.Pain and function recovered after radical neurotomy of the medial plantar nerve. A correct diagnosis is an essential starting point in the treatment of neurofibromas and a misdiagnosis may lead to an inappropriate treatment.     

Morton's neuroma: A clinical versus radiological diagnosis

BackgroundThe aim of our study was to compare the clinical versus radiological diagnosis of patients suffering from a Morton's neuroma.MethodsClinical assessments and pre-operative radiological imaging of patients who had excision of a Morton's neuromas were retrospectively compared.Results43 neuromas were excised from 36 patients over 68 months. The commonest clinical symptoms were tenderness on direct palpation (100%), pain on weight bearing (91%) which was relieved by rest (81%). The most sensitive clinical sign was a Mulder's click. Clinical assessment had a sensitivity of 98% (42/43). Ultrasonography had a sensitivity of 90% (28/31) and magnetic resonance imaging had a sensitivity of 88% (14/16).ConclusionThere is no absolute requirement for imaging patients who clinically have a Morton's neuroma. The two main indications for imaging are (a) an unclear clinical assessment and (b) cases when more than one web space is affected. Ultrasonography should be the investigation of choice.     

Regenerative surgery of the complications with Morton's neuroma surgery: use of platelet rich plasma and hyaluronic acid

Morton's neuroma is an entrapment neuropathy of the plantar digital nerve. We treated five patients with wound dehiscence and tendon exposure, after Morton's neuroma surgery excision using a dorsal approach. In this article we describe our technique. From July 2010 to August 2011, at the Department of Plastic and Reconstructive Surgery, University of Rome ‘Tor Vergata’, five patients (four females and one male), with ages ranging between 35 and 52 years, were treated with a combination of PRP (platelet rich plasma) and HA (hyaluronic acid). Thirty days following surgery, all patients showed a complete healing of the wound. The use of this technique for the treatment of postoperative wound dehiscence and tendon exposure has proven as satisfactory.     

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.     

MRI and ultrasonography in Morton's neuroma: Diagnostic accuracy and correlation

Background:

The diagnosis of Morton''s neuroma is based primarily on clinical findings. Ultrasonography (US) and magnetic resonance image (MRI) studies are considered complementary diagnostic techniques. The aim of this study was to establish the correlation and sensitivity of both techniques used to diagnose Morton''s neuroma.

Materials and Methods:

Thirty seven patients (43 intermetatarsal spaces) with Morton''s neuroma operated were retrospectively reviewed. In all cases MRI or ultrasound was performed to complement clinical diagnosis of Morton''s neuroma. In all cases, a histopathological examination confirmed the diagnosis. Estimates of sensitivity were made and correlation (kappa statistics) was assessed for both techniques.

Results:

Twenty seven women and 10 men participated with a mean age of 60 years. Double lesions presented in six patients. The second intermetatarsal space was affected in 10 patients and the third in 33 patients. An MRI was performed in 41 cases and a US in 23 cases. In 21 patients, both an MRI and a US were performed. With regard to the 41 MRIs performed, 34 were positive for Morton''s neuroma and 7 were negative. MRI sensitivity was 82.9% [95% confidence interval (CI): 0.679–0.929]. Thirteen out of 23 US performed were positive and 10 US were negative. US sensitivity was 56.5% (95% CI: 0.345–0.768). Relative to the 21 patients on whom both techniques were carried out, the agreement between both techniques was poor (kappa statistics 0.31).

Conclusion:

Although ancillary studies may be required to confirm the clinical diagnosis in some cases, they are probably not necessary for the diagnosis of Morton''s neuroma. MRI had a higher sensitivity than US and should be considered the technique of choice in those cases. However, a negative result does not exclude the diagnosis (false negative 17%).     

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.     

Rheumatoid nodule presenting as Morton’s neuroma

Among 101 feet that presented with symptoms and signs similar to Morton’s neuroma, intermetatarsal rheumatoid nodules were found in five feet (three patients). Two patients had bilateral involvement. Histology of the excised tissue showed the presence of a rheumatoid nodule and Morton’s neuroma in four feet and a rheumatoid nodule with unremarkable nerve bundles in one. A rheumatoid nodule can coexist with Morton’s neuroma, as seen in our patients, and the presentation is often similar to that of a Morton’s neuroma. Our patients were rendered asymptomatic with surgical treatment and went on to have appropriate management of rheumatoid arthritis. Rheumatoid nodule should be considered in the differential diagnosis of Morton’s neuroma in not only rheumatoid arthritis patients but also asymptomatic patients who have never been tested for rheumatoid antibodies.     

Morton's disease: optic and electron microscopy observations

The authors performed an optic and electron-microscope investigation above the common digital nerve of the foot, whose fragments had been surgically removed from patients suffering from "Morton metatarsalgia" (neuroma). Histological sections were taken from pre-stenotic swelling in patients with clinical symptoms persisting for one year; perineural thickening without evidence of fibroblastic proliferation could be demonstrated, together with an intraneural deposition of an amorphous substance. In other patients suffering from Morton's disease for a longer time, a more pronounced epineural thickening in the pre-stenotic zone could be shown, with partial replacement of nerve fibers by amorphous substance. In the same patients endoneural fibrositis was seen at the level of the stenosis. Electron-microscopy in patients after one year showed an increase in collagenous endoneural fibers and microfibrils. These histopathological findings suggest a compressive mechanism in the pathogenesis of the damage to the common interdigital nerve in Morton's disease, caused by the extrinsic anatomical structures surrounding the nerve. The so-called "neuroma" can be identified with the pre-stenotic swelling.     

Histological and ultrastructural changes in the undersurface of the acromion with subacromial impingement

Background We examined histological changes in the undersurface of the acromion in patients with symptoms of subacromial impingement, in order to clarify whether or not these changes are the main cause of rotator cuff tear.

Methods We studied 39 shoulders. The undersurface of the acromion and the coracoacromial ligament were examined by light microscopy and transmission electron microscopy.

Results The distinct four-layer structure seen in the undersurface of the acromion of normal subjects was not found in any of our patients. In patients with full-thickness cuff tear, the extent of the tear had a greater association with the degree of degeneration in the undersurface of the acromion than age or the duration of illness. There was little association between structural changes in the coracoacromial ligament and the extent of or the presence of full-thickness cuff tear, or the duration of illness, but there was a strong association with patient age.

Interpretation The histological changes in the undersurface of the acromion in patients without cuff tear were merely minute changes compared to those in patients with full-thickness cuff tear. We conclude that the advanced degenerative changes in the undersurface of the acromion result from full-thickness cuff tear.     

Treatment of recurrent neuroma of the interdigital nerve by implantation of the proximal nerve into muscle in the arch of the foot

A prospective study was done to evaluate the results of treating recurrent "Morton's" neuroma by a technique that combined resecting the interdigital neuroma through a plantar approach and implantation of the proximal end of the nerve into an intrinsic muscle in the arch of the foot. As a part of this study, quantitative sensory testing was done for the medial plantar and medial calcaneal nerves. Seventeen recurrent interdigital neuromas were resected in 13 patients. Pain was identified on physical examination as being due to neuromas located in the first (one), second (six), third, (eight) and fourth (two) web spaces. Seven of the 13 patients were found to have, by quantitative sensory testing and physical examination, an associated tarsal tunnel syndrome responsible for symptoms related to numbness in the foot in addition to the pain of the recurrent neuroma. These patients had tarsal tunnel decompression at the time of the neuroma resection. At a mean follow-up time of 33.8 months (range 24-42 months), done by direct physician interview and examination, 80% of the patients had excellent relief of symptoms, returned to their regular job, and wore usual footwear. Twenty percent of the patients had good relief of symptoms, worked at a different job, and had to change their footwear. It is concluded that recurrent pain after a dorsal interdigital neurectomy can be treated successfully through a plantar approach with implantation of the proximal end of the nerve into an intrinsic muscle. This study also identified an association of tarsal tunnel syndrome in 54% of this series of patients with recurrent Morton's neuroma.     

The outcome of Morton’s neurectomy in the treatment of metatarsalgia

Morton’s neuroma is a common cause of metatarsalgia caused by intermetarsal digital nerve thickening. This study reviews the pathology, presentation, symptoms and signs, and patient satisfaction with surgical treatment. Seventy-eight patients (82 feet) were treated for Morton’s metatarsalgia by excision of the interdigital nerve. The patients were followed-up for a mean of 4.6 years (range 0.8–8.1 years) and scored using the Foot Functional Index and the American Orthopedic Foot Ankle Society scoring system. In 74 patients the Foot Functional Index was more than 85 (maximum score 100). Seventy-one patients scored more than 90 on the American Orthopedic Foot Ankle Society scoring system with two patients scoring 100 (maximum score). Postoperatively, 82% reported excellent or good results, 10% had a fair result with restriction of activities or pain and 8% had no improvement at all after surgery while 71% had restrictions with footwear.