Abstract
Category:
Trauma
Introduction/Purpose:
Treatment of talus fracture is difficult. Because talus fracture often cause the avascular necrosis, and necessitate a prolonged non-weight-bearing period or arthrodesis in these cases. Identification of the fracture type that results in necrosis before a surgery may help in the determination of the planning of treatment and the prognosis. However, necrosis cannot be identified directly by a conventional fracture classification. We investigated the sites in which fracture lines of the talus are visible by using CT to determine the association between fracture of the talus and the occurrence of necrosis.
Methods:
Twenty-five patients (25 feet; 18 men and 7 women; mean age at the first visit, 48.4 years [range, 15–80 years]) treated through 2003 to 2013 were included in this study.
Fracture lines were assessed using radiography and CT. According to the conventional classification, 12 neck fractures and 13 body fractures were found. The Inokuchi–Ogawa classification was used to assess the fracture line on the subtalar joint surfaces. A fracture line was defined as the line connecting 1 with the other point as follows: (a) the sulcus tali ; (b) the sinus tarsi; (c) between the lateral process and the lateral tubercle; and (d) the medial tubercle. MRI was used for the assessment of necrosis. The subjects were divided into the non-necrosis group (group A) and the necrosis group (group B), and relationship between fracture lines and appearance of necrosis was examined.
Results:
With the exclusion of 2 unclassifiable cases, group A consisted of 15 feet, whereas group B consisted of 8 feet. At the Inokuchi–Ogawa classification, 1fracture line was found in 8 feet,2:5, and and 3:1 in group A. In group B, all cases showed multiple fracture lines. Among the lines connecting a-b, a-c, and b-d, fracture was observed in more than 2 lines in the all cases .
Conclusion:
The most important factor for determining the prognosis of talus fracture is the presence or absence of necrosis. The results of this study indicate that fracture lines connecting a-b, a-c, and b-d interrupt major blood routes, and talus fracture more than 2 fracture lines were highly likely to develop avascular necrosis. Thus, fracture lines may predict the occurrence of necrosis and possible sites of its occurrence.