Relationship between the histological findings of spondylolytic tissue, instability of the loose lamina, and low back pain.

Study Design: We investigated the histomorphological features of the tissue occupying the spondylolytic defect (spondylolytic tissue), which was similar to ligament, and then graded the complete enthesis structure and the density of the fibrous portion. The relationships between the features, instability of the loose lamina against the affected vertebra, and the severity of low back pain were studied.

Objective: To elucidate the histomorphological features of spondylolytic tissue and the associations between the features, instability of the loose lamina, and low back pain.