Extreme elongation of the transverse processes of the fifth lumbar vertebra: an unusual variant.

The fifth lumbar vertebra has massive transverse processes that are continuous with the pedicle and encroach the body of the vertebra. These processes are mainly meant for the attachment of the iliolumbar ligament. With increasing age, the iliolumbar ligament can undergo secondary degenerative changes such as calcification, hyalinization, and myxoid degeneration. The authors present the incidental discovery of extremely elongated transverse processes of the fifth lumbar vertebra in a 45-year-old woman who underwent surgery for an intervertebral disc herniation. We also propose a possible pathogenesis to explain this rare condition and conclude that this unusual variant may be caused by calcification of the iliolumbar ligament rather than a congenital anomaly.