Correlation between Subluxation of Calcaneocuboid Joint and Residual Forefoot Adduction in Congenital Clubfoot

Ok, In Young; Lee, Han Yong; Lee, Kyung Tai; Koh, Young Seok

Abstract

Residual adduction of the forefoot is recognized as common sequelae of treated clubfoot. The causes of residual forefoot adduction may be metatarsus varus, talonavicular subluxation and subluxation of the calcaneocuboid joint. But, less attention has been given to subluxation of the calcaneocuboid joint. The purpose of this study was to assess the correlation between subluxation of calcaneocuboid joint and residual forefoot adduction, and to suggest the guideline of treatment for subluxation of the calcaneocuboid joint. A retrospective analysis was done by the medical records and radiographs of 48 clubfeet (thirty-four patients) that had been treated with an operation (thirty-three feet) or conservative methods (fifteen feet) at the Kang-Nam St. Mary's Hospital, between 1990 and 1995. The severity of adduction of the forefoot was determined by the angle of talo-first metatarsal. Subluxation of the calcaneocuboid joint was measured by using a grading system. And then, the forefoot adduction was categorized to mild, moderate, and severe degree according to the talo-first metatarsal angle. The average length of follow-up was eighteen months. Of the 48 feet, seventeen had no subluxation of the calcaneocuboid joint (35.4%), twenty-seven Grade I subluxation (56.3%), and four Grade 3 subluxation (8.3%) on initial radiograph. On the final radiograph, twenty-five feet had a residual adduction of the forefoot. In reviewing the distribution of the residual forefoot adduction according to the initial grade of the calcaneocuboid joint subluxation, Grade 0 subluxation had 6 forefoot adduction (35.3%), Grade I subluxation had 15 forefoot adduction (55.6%), and Grade 3 subluxation had 4 forefoot adduction (100%). Grade II calcaneocuboid joint subluxation had two severe residual forefoot adduction deformities (2 out of 4 cases) and Grade I calcaneocuboid joint subluxation had one severe residual forefoot adduction deformity (1 out of 15 cases). But, there was no severe forefoot adduction deformity in Grade 0 calcaneocuboid joint subluxation. The average angle of talo-first metatarsal was decreased in Grade 0 and Grade I subluxation, whereas it was increased in Grade II subluxation. Conclusively, we believe that there is significant correlation between the severity of subluxation of calcaneocuboid joint and residual forefoot adduction, and that the patients who have a Grade II subluxation of calcaneocuboid joint need operative correction of the subluxation of the calcaneocuboid joint.