According to the Wiltse etiological classification of spondylolisthesis, which type is the most common variety encountered in adults?
- A Type I, dysplastic (congenital)
- B Type III, degenerative
- C Type II, isthmic ✓
- D Type V, pathological
Correct answer: C. Type II, isthmic
Explanation
Wiltse divided spondylolisthesis into dysplastic, isthmic, degenerative, traumatic and pathological types. The isthmic type, caused by a fatigue fracture of the pars interarticularis, is the commonest form, especially at L5-S1 in adolescents and young adults. Dysplastic slips are congenital and can progress severely, while the degenerative type occurs in older patients, typically at L4-L5 with an intact neural arch.
Reference: Essential Orthopaedics (Maheshwari), 5th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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