A Study on the Fracture Pattern of Posterior Fossa.

Chee, Sun Ho

Original Article

Journal of Korean Neurosurgical Society 1977;6(2): 357-362.

Department of Neurological Surgery, Ewha Womans University School of Medicine, Seoul, Korea.

ABSTRACT

This study has been made to stress the importance of fracture pattern of the posterior fossa for recognition of traumatic lesions in the posterior fossa. Included in the series are all the cases of clinically significant verified lesions in the posterior fossa due to posterior fossa fractures. The classification of posterior fossa fractures introduced here by author has been based on the linear fracture involving the transverse sinus groove and/or the foramen magnum in Towne's projection. Five types of pattern have occurred. In type I, a linear fracture involves the transverse sinus groove and the foramen magnum. In type II, a linear fracture involves the transverse sinus groove but not the foramen magnum. In type III, a linear fracture involves the lambdoid suture, the transverse sinus groove and the foramen magnum. In type IV, a linear fracture involves the lambdoid suture and the transverse sinus groove, but not the foramen magnum. In type V, a linear fracture of the suboccipital bone involves the foramen magnum, but not the transverse sinus groove. In a total of 33 cases of posterior fossa fracture, 13 cases(39.3%) are of type I, 7 cases(21.2%) are of type II, 5 cases(15.2%) are of type III, 5 cases(15.2%) are of type IV, 3 cases(9.1%) are of type V. It has been shown that the cerebellar hematomas have been verified in type I, epidural and subdural hematomas verified in all the types without regard to the fracture patterns, and subdural hygromas verified in type I, III and V.