Radiographic Analysis of Feet With and Without Morton's Neuroma.
BACKGROUND
The aim of this research was to investigate the association of various structural measurements of the forefoot with Morton's neuroma (MN).


METHODS
Weightbearing anteroposterior and lateral foot radiographs of subjects attending the University of Western Australia (UWA) Podiatry Clinic and the first author's private practice were included in this study. A single assessor measured the following angles: lateral intermetatarsal angle (LIMA), intermetatarsal angle (IMA), hallux valgus angle (HVA), digital divergence between the second and third digits (DD23), digital divergence between the third and fourth digits (DD34) and relative metatarsal lengths of the first to fifth metatarsals (Met1-5), and the effect of MN size as measured by ultrasonograph on digital divergence. Intratester reliability of all radiographic measurements was assessed on all radiographic measurements. The study included 101 subjects, of whom 69 were diagnosed with MN and 32 were control subjects without MN. The mean (± standard deviation) age of MN subjects was 52 (±15) years and for control subjects, 48 (±12) years.


RESULTS
When comparing all feet, there were no significant differences in the LIMA, HVA, IMA, digital divergence angles and the relative metatarsal distances between subjects with MN and control subjects. No relationship between MN size and digital divergence was found in either foot, or in either neuroma location.


CONCLUSIONS
We were unable to demonstrate any relationship in this study between radiographic metatarsal length and angular measurements in a symptomatic MN group compared to a control group. In addition, we did not find any correlation between the size of MN as measured from ultrasonographic images and radiographic evidence of digital divergence.


METHODS
Level III, case control study.
1 Podiatric Medicine Unit M422, School of Surgery, University of Western Australia, Crawley, Western Australia, Australia.
Reza
R
Naraghi
2 School of Population Health M431, University of Western Australia, Crawley, Western Australia, Australia.
Alexandra
A
Bremner
3 School of Dentistry M512, University of Western Australia, Crawley, Western Australia, Australia.
Linda
L
Slack-Smith
1 Podiatric Medicine Unit M422, School of Surgery, University of Western Australia, Crawley, Western Australia, Australia.
Alan
A
Bryant
D016022:Case-Control Studies; D005528:Foot; D006215:Hallux Valgus / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008682:Metatarsal Bones / Q000601:surgery*; D000070607:Morton Neuroma / Q000503:physiopathology / Q000601:surgery*; D011859:Radiography / Q000379:methods*; D015203:Reproducibility of Results; D016474:Weight-Bearing / Q000502:physiology*
Morton’s neuroma; digital divergence; metatarsal length; radiographic measurements