Spondylarthrography: the demonstration of spondylolysis by apophyseal joint arthrography.

Twenty selected patients with spondylolysis have been studied following apophyseal joint arthrography. In each instance a communication with the defect of the pars interarticularis was demonstrated by the extension of contrast medium from injection into the adjacent facet joint. The clinical and radiological features are described. The anatomical basis of the abnormality is presented using macroscopic and radiographic correlation from a dissected cadaveric specimen of spondylolysis. Sixty-five per cent of the patients experienced significant relief of pain symptoms when long-acting local anaesthetic was introduced into the facet joint.