Undiagnosed fracture in a common foot variant: the biphalangeal little toe

The incidence of biphalangeal fifth toe: Comparison of normal population and patients with foot deformity

BACKGROUND

Pedal biphalangism, which was also defined as symphalangism, is seen at a frequency that cannot be ignored; however, no study can be found in the literature evaluating biphalangism in normal population in comparison to those who have foot disorders. The aim of this study was to evaluate the incidence of the pedal fifth toe symphalangism in normal population and in patients with foot deformity including hallux valgus, pes planus, pes cavus, and pes equinovarus. We hypothesized that pedal fifth toe symphalangism may be a predisposing factor or an accompanying structural variation for foot deformity.

MATERIALS

Patients admitted to the emergency department of our center in October and November 2016 were defined as the control group, and patients with the diagnosis of hallux valgus, pes planus, pes cavus, and pes equinovarus treated between 2011 and 2016 in our department were defined as the foot deformity group. Individuals who had anteroposterior, oblique, and lateral radiographs of foot were included in the study.

RESULTS

One thousand and four patients participated in the cross-sectional observational study. Biphalangeal fifth toe was found in 328 of 1004 (32.7%) patients. In foot deformity group ( n = 672), 222 patients (33%) had biphalangeal fifth toe. In the control group, 106 (31.9%) of the 332 patients had biphalangeal fifth toe. There was no statistically significant difference in the incidence of biphalangeal fifth toe between the two groups ( p = 0.72).

CONCLUSIONS

According to the results of this study, biphalangeal fifth toe is a common pedal anatomical variant seen approximately in one-third of the population who have either foot deformity or not. This information may be valuable for podiatrist undertaking the conservative or surgical treatment of fifth toe-related disorders.

Prevalence of toe symphalangism in Hong Kong Chinese population

Objective:

To explore the prevalence and variations of toe symphalangism in the Hong Kong Chinese population.

Methods:

A retrospective review of foot radiographs taken in Chinese adult patients admitted to United Christian Hospital from 1 January, 2016 to 31 December, 2016. Exclusion criteria include (1) previous toe amputation, (2) skeletal immaturity, (3) severe deformity, and (4) repeated attendance. The frequencies were compared by χ 2 test.

Result:

A total of 1364 foot radiographs were reviewed. Six-hundred sixty radiographs were excluded. A total of 704 radiographs were included in this study. There were total 849 feet reviewed (left: 290, right: 269, bilateral: 145). Their mean age (± standard deviation) was 59.5 ± 14.2 years. The prevalence of 2nd, 3rd, 4th, and 5th toe symphalangism was 0.2%, 0.8%, 9.9%, and 76.7%, respectively. The prevalence resembles Asian population. There was no significant difference in the prevalence associated with the following factors: (1) gender and (2) left versus right foot. There was no 4th toe symphalangism without 5th toe involvement. In the 145 bilateral feet radiographs, asymmetrical distribution of toe symphalangism was found in 8.2%. Second toe symphalangism is rare (0.24%).

Conclusion:

This is the first study in Hong Kong to report prevalence of toe symphalangism in Chinese population. There is a high prevalence rate of 5th toe symphalangism in the Hong Kong Chinese Population. This implies less flexible lesser toes in the Chinese population with higher risks of development of deformities. The clinical implication of such findings needs further research.

Giant cell tumor of the distal phalanx of the biphalangeal fifth toe: a case report and review of the literature

Giant cell tumor of the distal phalanx of a toe is rather unusual. We report an unusual case of giant cell tumor arising at the distal phalanx of the left biphalangeal fifth toe in a 13-year-old boy. This was treated successfully with curettage and packing with bone substitution.