RESUMO
PURPOSE: the os trigonum is a supernumerary bone that may lead to posterior ankle impingement syndrome. The present study aims to assess the prevalence of this bone. METHODS: A meta-analysis regarding the presence of the os trigonum was performed. For this, the MEDLINE and SciElo databases were searched using "os trigonum" as the keyword. Only original articles, theses, books, dissertations, and monographs were included. Papers with a sample size of < 50 individuals were excluded. The data extracted from the articles were: the total sample size, the prevalence of the trigonum, the method of analysis, the region of the sample, and data regarding sex and side (left or right). Statistical analysis was performed using MedCalc Statistical Software version 14.8.1 (MedCalc Software bvba, Ostend, Belgium). The heterogeneity between the studies was assessed using the I² estimation and the Cochran Q test. For all analyses, a random effect was used and a value of p < 0.05 was considered significant. RESULTS: 249 papers were found, while 18 were included in the meta-analysis. A total of 17,626 ankles were included. The pooled prevalence of the os trigonum was 10.3% (95% CI 7-14.1%) in the present study. There was no significant difference regarding sex or side, while studies conducted in imaging exams showed a higher prevalence in comparison to cadaveric studies. CONCLUSION: Our results suggest that the os trigonum is relatively common. Knowledge of the prevalence of the os trigonum may help surgeons and clinicians diagnose posterior ankle impingement syndrome.
Assuntos
Articulação do Tornozelo , Tálus , Humanos , Prevalência , Tálus/anormalidades , Variação Anatômica , Feminino , MasculinoRESUMO
SUMMARY: The os intermetatarseum is an accessory bone located in the foot, usually between the first 2 metatarsals and the cuneiform bone. It can be presented as free, articulated or in a fused fashion. It is a very unusual variation found in less than 13 % of the population. A 27-year-old patient presented to the emergency service due to an ankle lesion. Physical exam showed pain and limited range of motion while supporting partial load. Radiographic imaging showed a bony trace near the base of the first and second metatarsals, diagnosed as the os intermetatarseum. Formation of this supernumerary bone begins as a separate ossification center. Most cases are asymptomatic; however, compression of the deep peroneal nerve branches by the os intermetatarseum can lead to pain. Some authors suggest that the presence of this bone may cause hallux valgus. The intermetatarseum can lead to diagnostic confusion, mainly related to Lisfranc fracture. Its origin is still little understood.
El os intermetatarseum es un hueso accesorio ubicado en el pie, generalmente entre los 2 primeros metatarsianos y el hueso cuneiforme. Puede presentarse de forma libre, articulada o fusionada. Es una variación muy inusual que se encuentra en menos del 13 % de la población. Paciente de 27 años que acude a urgencias por lesión en tobillo. El examen físico mostró dolor y rango de movimiento limitado mientras soportaba una carga parcial. Las imágenes radiológicas mostraron un rastro óseo cerca de la base del primer y segundo metatarsianos, diagnosticado como os intermetatarseum. La formación de este hueso supernumerario comienza como un centro de osificación separado. La mayoría de los casos son asintomáticos; sin embargo, la compresión de las ramas profundas del nervio fibular en el espacio intermetatarsiano puede provocar dolor. Algunos autores sugieren que la presencia de este hueso puede provocar hallux valgus. El hueso intermetatarsiano puede llevar a confusión diagnóstica, principalmente relacionada con la fractura de Lisfranc. Su origen aún es poco comprendido.