EPIDEMIOLOGICAL FACTORS OF HALLUX RIGIDUS

Abstract

Introduction and purpose: The expression hallux rigidus is used to describe a situation characterized by pain and a decrease in range of movement of the first metatarsophalangeal joint: the head of the first metatarsal moves on a sagittal plane without a stable surface, in spite of stabilizers such as the phalanx itself and the gleno-sesamoid system. The aim of this retrospective study is to define demographic data and their association with etiological, clinical and radiological factors in patients with primary hallux rigidus.

Materials and methods: We reviewed the records of one hundred and forty patients operated in our department between 1995 and 2005 for hallux rigidus. We selected 66 cases of primary hallux rigidus with complete clinical records. We excluded all secondary hallux rigidus cases from the study.

Results: We carried out comparative ANOVA studies to validate the relationship between weight and degree of hallux rigidus, as well as the relationship with BMI (body mass index), the value of the hallux valgus and distal hallux angle, the value of the adductor and the intermetatarsal angle. All these data were studied for a confidence interval of 95% and 90%. No statistically significant relationship was found, which does not mean that there may not be a relationship between parameters. Moreover, a direct relation was found between gender and development of hallux rigidus (p=0.095), which is statistically significant for a confidence interval of 90%. Height is also a parameter related to hallux rigidus, the greater the height of the patient the greater the development of hallux rigidus (p=0.067) for a 90% confidence interval. A radiological parameter statistically related to hallux rigidus is the elevation of the first metatarsal (p=0.075) for a confidence interval of 90%.

Conclusions:

1. Female sex and a greater frequency of hallux rigidus have a statistically significant relationship (p=0.095) for a 90% confidence interval. This is contrary to the opinion expressed in most of the literature published up to the present.

2. The height of the patient and a greater frequency of hallux rigidus seem to have a statistically significant relationship for a 90% confidence interval (p=0.067). This has not been mentioned up to now in any published paper.

3. The metatarsus primus elevatus is the only anatomical-radiological factor that we found, in our study, to have a statistically significant relationship with the appearance of hallux rigidus (p=0.075) for a 90% confidence interval.

4. For factors such as hypermobility of the 1^st toe, excess of the 1st axis, adductor metatarsus, interphalangeal hallux valgus and chevron shaped joint, we have found no significant relationship with the development of hallux rigidus.