Wiltse Classification
Classification of Spondylolisthesis

1.) Dysplastic : Congenital malformation of the sacrum or neural arch of L5.

2.) Isthmic: Stress fracture, elongation, or acute fracture of the pars.

3.) Degenerative: Long-standing arthritic process of the zygapophyseal joints.

4.) Traumatic: Neural arch fracture excluding the pars region.

5.) Pathologic: Bone disease – Paget’s, Metastatic disease, or [[Osteopetrosis]].

6.) Iatrogenic: Following lumbar spine surgery

Reference: Wiltse LL, Newman PH, Macnab I. “Classification of spondylolysis and  spondylolisthesis.” Clin Orthop Relat Res. 1976 Jun;(117):23-9.