Instrumental and clinical diagnosis of interdigital Morton neuroma

Abstract

Background: Interdigital neuroma is one of the most common diseases in foot surgery. It is a common cause of metatarsalgia leading to debilitating pain. At the same time, the diagnosis of neuroma can be a difficult task for an orthopedic surgeon due to the complex anatomy of the forefoot and a large number of soft-tissue and bone structures. Besides, the existing manual testing methods are not pathognomonic specifically for neuroma. The clinical symptoms and history, as well as a physical exam and instrumental evidence are important in assessing and grading the disease. However, there are no recommendations in the modern Russian literature regarding the need for routine visualization of neuroma. The reproducibility of the study, the absence of ionizing radiation and the possibility of obtaining a second opinion, as well as high sensitivity makes magnetic resonance imaging an important diagnostic tool in the diagnosis of neuroma. Aim: To evaluate the importance of the anamnesis and complaints and the sensitivity of clinical tests and magnetic resonance imaging of the foot in the diagnosis of interdigital neuromas. Methods: The study presents a retrospective analysis of the medical histories and outpatient records of 28 patients (8 men and 20 women) treated at the EMC ECSTO in the period from 2017 to 2022. The examination was performed according to a standardized protocol: collection of complaints and anamnesis, palpation, manual testing, including Mulder's click test. As a part of examination, magnetic resonance imaging of the foot was performed for all the patients. The average patient’s age at the time of the surgical treatment was 45 years. The resection of a part of the affected nerve with the subsequent histological examination was considered a gold standard for the treatment and verification of interdigital neuromas. In all the cases, the histopathological study confirmed the diagnosis. Results: The sensitivity of magnetic resonance imaging in the diagnosis of interdigital neuromas was 86%, the sensitivity of the Mulder test was 61%. Pain during the palpation of the affected interdigital space was determined in 100% of cases. Conclusion: The combination of a manual examination and magnetic resonance imaging, along with the analysis of complaints and anamnesis makes it possible to diagnose Morton's neuroma in most cases.