US and MRI of the Forefoot: Intermetatarsal Bursitis or Morton's Neuroma

Study Overview
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Brief Summary
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The aim of this study is to investigate the incidence of intermetatarsal bursitis and Morton's neuroma in patients with metatarsalgia (i.e. pain in the forefoot) and control subjects by diagnostic imaging with ultrasound and MRI.

Detailed Description
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In a group of patients with intermetatarsal pain found by an orthopedic surgeon, the investigators want to assess the incidences of intermetatarsal bursitis and Morton's neuroma, using diagnostic imaging; ultrasound and MRI. The hypothesis is, that intermetatarsal bursitis is an overlooked diagnosis in patients with metatarsalgia. As a result of sparse literature and lack of knowledge about this condition with symptoms mimicking Morton's neuroma, a part of patients diagnosed with Morton's neuroma, suffers from intermetatarsal bursitis instead. Additionally, the investigators want to evaluate the clinical sign opening toes. Based on clinical photos of the feet, the investigators want to document the presence of opening toes and investigate if there is a correlation with either intermetatarsal bursitis and/or Morton's neuroma.

Official Title
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Ultrasound and MRI of the Forefoot: Intermetatarsal Bursitis or Morton's Neuroma

Conditions
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Intermetatarsal Bursitis, Morton Neuroma, Intermetatarsal Neuroma

Intervention / Treatment
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* Diagnostic Test: MRI with contrast
* Diagnostic Test: Ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Pain in an intermetatarsal space (patient group) Exclusion Criteria: Age <18 years Open wounds or ongoing infection in the forefoot at the time of examination Persons with contraindications to participate in MRI scan Persons with a history of significant trauma in the forefoot, e.g. any fracture or previous surgeries in the forefoot Persons who have previously received treatment for Morton's neuroma in the same foot, e.g. injection (within 6 months) or operation (anytime) Persons with severely impaired renal function (GFR <30 ml/min) Persons with a systemic inflammatory condition like rheumatoid arthritis, due to clinically silent intermetatarsal bursitis in this group (control group)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This is a diagnostic study with a patient and a control group.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patient group<br>Patients with intermetatarsal pain have ultrasound and MRI done | Diagnostic Test: MRI with contrast<br>* MRI of the forefoot with contrast (Gadovist)<br>Diagnostic Test: Ultrasound<br>* Ultrasound imaging of the forefoot<br>|
| Active Comparator: Control group<br>Healthy individuals (no forefoot pain) undergo ultrasound and MRI scan of the forefoot. | Diagnostic Test: MRI with contrast<br>* MRI of the forefoot with contrast (Gadovist)<br>Diagnostic Test: Ultrasound<br>* Ultrasound imaging of the forefoot<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of intermetatarsal bursitis on MRI | High intensity on T2 weighted images, low signal on T1. Thin peripheral enhancement on T1 contrast enhanced pictures. | 8 weeks | 
| Incidence of intermetatarsal bursitis on US | Hypoechoic mass between metatarsal heads closest to dorsal surface of foot. Compressible. Activity on power/color doppler. | 8 weeks | 
| Incidence of Morton's neuroma on MRI | Low to Intermediate signal in T1 and T2. Contrast enhancement of the nodular focus. | 8 weeks | 
| Incidence of Morton's neuroma on US | Hypoechoic mass between metatarsal heads closest to plantar surface of foot. Non-compressible. The interdigital nerve can be seen entering the mass. Close relation to the interdigital artery. | 8 weeks | 
| Incidence of other pathology on MRI | Other pathology than intermetatarsal bursitis or Morton's neuroma. | 8 weeks | 
| Incidence of other pathology on US | Other pathology than intermetatarsal bursitis or Morton's neuroma. | 8 weeks | 
| Incidence of normal findings on MRI | When no findings is observed. | 8 weeks | 
| Incidence of normal findings on US | When no findings is observed. | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opening toes | Presence of opening toes/V-sign/spreading toes. | 8 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Forefoot pain, Metatarsalgia