Co-existence of spina bifida occulta and lumbosacral transitional vertebra in patients presenting with lower back pain

Abstract

Lower back pain is a common symptom, which is managed by various specialties including neurology, orthopedics, general medicine, and rheumatology. Lumbosacral transitional vertebra (LSTV) is an important cause of back pain, about which many clinicians are unfamiliar. It is a congenital malformation of the spine, which results from abnormal fusion of the sacrum with the vertebra above, to a variable extent. An extra joint is formed between the ala of sacrum and the elongated transverse process of the vertebra above on one or both sides. It leads to altered rotational movement of the lower spine, which gives rise to back pain. Spina bifida occulta (SBO) is another congenital malformation of the spine, which is detected incidentally because it does not cause any symptoms. We observed frequent co-existence of SBO and LSTV in patients attending our rheumatology clinic for lower back pain.

Keywords: Bertolotti’s syn- drome; back pain; lumbosacral transitional vertebra; spina bifida occulta.

Fig. 1

Radiographs of the pelvis, antero-posterior projections of cases 1 to 5. Type IIA lumbosacral transitional vertebra (LSTV) on the right side (white arrow) and spina bifida occulta (SBO) of the fifth lumbar vertebra (L5) (encircled area) (A). Type IA LSTV on the right side (white arrow) and SBO of L5 (encircled area) (B). Type IIIB LSTV (white arrows) and SBO of L5 (encircled area) (C). Type IV LSTV (type II on the right [white arrow] and type III on the left side [asterisk]) and SBO of L5 (encircled area); bilateral sacroiliitis is also present (D). Type IIA LSTV on the left side (white arrow) and SBO of the sacrum (encircled area) (E).