Fracture - dislocation

A Bennetts fracture dislocation involves the base of the first metacarpal bone, which is pulled dorsally and radially.

The Monteggia fracture dislocation consists of fracture of the ulna with dislocation of the radial head. Four types may be distinguished.

Galeazzis fracture dislocation is the combination of radial fracture and subluxation or dislocation of the inferior radioulnar joint (Fig.1). The ulnar head is displaced in a dorsal, distal or medial direction.

Essex Lopresti fracture dislocation is an injury to the forearm consisting of a comminuted and displaced fracture of the radial head with subluxation or dislocation of the distal radioulnar joint.

Lisfrancs fracture dislocation involves the tarsometatarsal joints.

Fracture dislocations of the spine may occur in the upper thoracic or thoracolumbar regions. In the upper thoracic spine, they are severe and unstable injuries usually resulting from a combination of hyperflexion and axial loading of the vertebrae combined with disruption of ligaments by rotatory and shear forces. Typically the fracture-dislocation involves two adjacent vertebrae. Rotatory malalignment of the pedicles and spinous process above and below the injury may also be seen. Imaging techniques useful for evaluation of these injuries include conventional tomography, CT scanning, and MR imaging. In the throracolumbar region, usually all three spinal columns are completely disrupted, with intervertebral subluxation or dislocation. The rotational "slice fracture" is a horizontal fracture involving the superior endplate and a horizontal sliver-like fracture of the vertebral body below the dislocation; the upper vertebra, intervertebral disc and slice fracture fragment are displaced as a unit, which pivots relative to the caudal vertebra. In some cases, severe dislocations may result in the appearance of two vertebral bodies on a single CT scan (the double vertebrae sign).

DR/RB