[Treatment of fractures of the posterior axial arch. Results of 41 cases].

The authors have treated 41 fractures of the neural arch of the axis without neurological impairment. Eleven cases were treated surgically and the remainder conservatively by traction for several weeks followed by cast immobilisation. Only one fracture failed to unite. In the surgical cases, an anterior interbody fusion was performed a few weeks after the accident. Thirty cases were followed up. The functional results were satisfactory in 27 and poor in three. The residual mobility of the neck was much better after conservative management with about two thirds range of normal movement both in the sagittal and horizontal planes. A study on cadavers showed that a displacement of up to 5 mm at the fracture site was compatible with good stability because the ligaments and the discs were normal. It is concluded that most cases should be treated conservatively and that surgical treatment should be given only to cases with considerable displacement, marked instability or in cases of non-union.