This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
ALONG accelerated tempo in investigations of syndromes of the lower part of the back during recent years, prespondylolisthesis and spondylolisthesis have been uncovered as relatively frequent findings. With reference to the defect in the neural arch, there has been speculation as to whether it has resulted from an intrauterine disturbance sufficient to fracture or to impede circulation to the isthmic portion, with the resultant defect of a pseudarthrosis, or whether there has been a developmental failure of bony fusion of the two separate ossification centers of this portion of the neural arch. We are prone to support the latter view and feel that other congenital anomalies of this isthmic portion may be present in addition. We seek to demonstrate some of these in the following presentation.
The defect in the neural arch referred to as spondylolysis or spondyloschisis involves the isthmic portion, or pars interarticularis, situated between the superior and
ROCHE MB, BRYAN CS. SPONDYLOLISTHESISAdditional Variations in Anomalies in the Pars Interarticularis. Arch Surg. 1946;53(6):675-682. doi:10.1001/archsurg.1946.01230060686007