Significant antenatal factors in the development of lumbar spinal stenosis.

STUDY

DESIGN

Adverse factors during pregnancy may permanently stunt the growth of the spinal canal. Subsequently, even in an optimal environment the canal cannot catch up in growth with the trunk and long bones because of its early maturation. The degree of retardation in canal size depends on the severity and timing of the adverse effect. The catch-up growth of the long bones mask the narrow canal, because the latter does not have growth potential, resulting in an adult of sufficient height and good proportions, but with a canal at risk for stenosis.

OBJECTIVES

To investigate the influence of the antenatal environment on the growth of the lumber spinal canal.

SUMMARY OF BACKGROUND DATA: To date, little is known about the effects of an adverse environment on the growth of the spinal canal, and no data have been reported on antenatal influencing factors.

METHODS

Lumbar magnetic resonance imaging scans from 58 patients were examined. Dimensions of the central spinal canals were measured by computerized image analysis and compared with the subjects' obstetric data from their mothers' pregnancies.

RESULTS

The L3 canal was found to be the most sensitive to the influence of the examined factors. Gestational age was the most significant factor; if short, it resulted in small adult canal. Small placental weight, greater maternal age, primiparity, low socioeconomic class, and low birth weight were also found to be significant in affecting the growth of the canal.

CONCLUSIONS

An adverse antenatal environment does have a permanent, retarding effect on the growth of the lumbar spinal canal.