Open AccessThe interphalangeal angle as a novel radiological measurement tool for Morton's neuroma – a matched case‐control study
Author(s) -
Zaleski Martin,
Tondelli Timo,
Hodel Sandro,
Rigling Dominic,
Wirth Stephan
Publication year - 2021
Publication title -
journal of foot and ankle research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.763
H-Index - 39
ISSN - 1757-1146
DOI - 10.1186/s13047-021-00502-7
Subject(s) - medicine , asymptomatic , magnetic resonance imaging , dorsum , nuclear medicine , histopathology , neuroma , surgery , radiology , pathology , anatomy
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.