Cross-sectional study of the prevalence of hyperextension of the first metatarsophalangeal joint and its relationship to onycholysis in women with hallux valgus.

BACKGROUND: Hallux Valgus (HV) deformity is associated with misalignment in the sagittal plane that affects the first toe. However, the repercussions of the first toe hyperextension in HV have been scarcely considered. The purpose of this study was to provide evidence of the association between first-toe hyperextension and the risk of first toenail onycholysis in HV. METHODS: A total of 248 HV from 129 females were included. The extension of 1st MTP joint was measured while the patient was in the neutral position of the hallux using a two-branch goniometer. The classification of the HV severity stage was determined by the Manchester visual scale, and the height of the first toe in the standing position was measured using a digital meter. An interview and clinical examination were performed to collect information on the presence of onycholysis of the first toe. RESULTS: Of the 248 HV studied, 100 (40.3%) had onycholysis. A neutral extension > 30 degrees was noted in 110 (44.3%) HV. The incidence of onycholysis was higher in HV type C than in type B (p = 0.044). The probability of suffering onycholysis in the right foot was 2.3 times greater when the neutral position was higher than 30 degrees (OR = 2.3; p = 0.004). However, this was not observed in the left foot (p = 0.171). Onycholysis was more frequent in HV with more than 2 cm height of the first toe (p < 0.001). For both feet, the probability of suffering onycholysis was greater for each unit increase in hallux height (right foot OR = 9.0402, p = 0.005; left foot OR = 7.6633, p = 0.010). CONCLUSIONS: The incidence of onycholysis appears to be significantly associated with HV showing more than 30º extension, and more than 2 cm height of the first toe. Height and hyperextension of the first toe together with first toenail pathology should be mandatory in the evaluation of HV.

Anomalías rotacionales en mujeres con hallux valgus. Estudio observacional / Rotational anomalies in women with hallux valgus. Observational study

Objetivos: Analizar las diferencias de lateralidad en el movimiento de rotación y torsión en la extremidad inferior y su posible influencia en el desarrollo del hallux abductus valgus.Pacientes y métodos: La muestra incluyó 129 mujeres. Se evaluó el grado de severidad del hallux abductus valgus, la rotación de cadera, la torsión tibial, la movilidad de la primera articulación metatarsofalángica, el índice postural del pie y el ángulo de progresión del pie. Resultados: Nuestros resultados mostraron que existían diferencias en la rotación externa entre ambas caderas de 2.34° (p < 0.001) y entre la rotación interna y externa de la cadera izquierda de 4.11° (p < 0.002). También se encontró una diferencia del ángulo de progresión del pie de 3° (p < 0.001), pero no hubo diferencias significativas entre la torsión tibial y el índice postural del pie (p > 0.05). Se encontró una diferencia en el rango de movimiento entre ambas primeras articulaciones metatarsofalángicas de 6.30° (p < 0.001), y se halló una relación entre la extensión y el rango de movimiento de la primera articulación metatarsofalángica y el hallux abductus valgus (p < 0.05). Conclusiones: En base a los resultados obtenidos en esta muestra, los datos apuntan a un mayor rango de movimiento de la primera articulación metatarsofalángica en el pie izquierdo. Los resultados también indican un probable predominio de rotación interna de la extremidad izquierda y de rotación externa de la extremidad derecha, que no mostraron asociación con el estadio del hallux abductus valgus en este estudio (AU)

Objectives: To analyze differences in laterality in rotational and torsional movement in the lower extremity and its possible influence on the development of hallux abductus valgus. Patients and methods: The sample included 129 women. The degree of severity of hallux abductus valgus, hip rotation, tibial torsion, mobility of the first metatarsophalangeal joint, foot posture index, and foot progression angle were evaluated. Results: Our results showed that there were differences in external rotation between both hips of 2.34° (p < 0.001) and between internal and external rotation of the left hip of 4.11° (p < 0.002). We also found a difference of the foot progression angle between feet of 3° (p < 0.001), but there was no significant difference between tibial torsion and foot posture index (p > 0.05). A difference in range of motion was found between both first metatarsophalangeal joints of 6.30° (p < 0.001), and a relationship was found between extension and range of motion of the first metatarsophalangeal joint and hallux abductus valgus (p < 0.05). Conclusions: Based on the results obtained in this sample, the data points to a greater range of motion of the first metatarsophalangeal joint in the left foot. The results also indicate a probable predominance of internal rotation of the left extremity and external rotation of the right extremity, which did not show asociation with the degree of hallux aductus valgus in this study (AU)