title: A finite-element analysis study of the metatarsophalangeal joint of the hallux rigidus.
abstract: Hallux rigidus was first described in 1887. Many aetiological factors have been postulated, but none has been supported by scientific evidence. We have examined the static and dynamic imbalances in the first metatarsophalangeal joint which we postulated could be the cause of this condition. We performed a finite-element analysis study on a male subject and calculated a mathematical model of the joint when subjected to both normal and abnormal physiological loads. The results gave statistically significant evidence for an increase in tension of the plantar fascia as the cause of abnormal stress on the articular cartilage rather than mismatch of the articular surfaces or subclinical muscle contractures. Our study indicated a clinical potential cause of hallux rigidus and challenged the many aetiological theories. It could influence the choice of surgical procedure for the treatment of early grades of hallux rigidus.
authors.affiliation: Cappagh National Orthopaedic Hospital, Finglas, Cappagh, Dublin 11, Ireland. flavinr@gmail.com
authors.forename: R
authors.initials: R
authors.lastname: Flavin
authors.forename: T
authors.initials: T
authors.lastname: Halpin
authors.forename: R
authors.initials: R
authors.lastname: O'Sullivan
authors.forename: D
authors.initials: D
authors.lastname: FitzPatrick
authors.forename: A
authors.initials: A
authors.lastname: Ivankovic
authors.forename: M M
authors.initials: MM
authors.lastname: Stephens
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D020342:Finite Element Analysis; D020859:Hallux Rigidus / Q000209:etiology*; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control; D008297:Male; D008683:Metatarsophalangeal Joint / Q000503:physiopathology*; D008954:Models, Biological; D016059:Range of Motion, Articular / Q000502:physiology*; D013314:Stress, Mechanical; D016474:Weight-Bearing