Source of Support: None, Conflict of Interest: None
Fifty years ago in our country spinal injuries were mainly the result of fall from a tree, while in the Western countries it was mainly because of accidents occurring in heavy complex industries and coal mining (Holdsworth 1963). With more participation in high speed travels and vigorous sports, the injuries of spine have increased many folds all over the world. Flexion, extension and rotational forces in excess are known factors responsible to produce fracture and dislocation of lumbar spine. Less has been emphasized about the horizontal shearing force leading to fracture dislocation of lumbar spine. However, Roaf (1960) explained the fracture dislocation of lumbar spine as a result of horizontal shearing force in combination with rotational forces. Horizontal shearing force alone causing fracture dislocation of the lumbar spine has not been described. Two cases are reported here in whom fracture dislocation of the lumbar vertebrae occurred predominantly because of horizontal shear force. Both the cases were admitted between January 1978 and February 1978.