1. An Unusual Cause of Low-Back Pain in Children by Glenn Lipton, Eric Riddle, Leslie Grissom, Temesgen Fitru, Harold Marks, and S. Jay Kumar J Bone Joint Surg Am Volume 83(10):1552-1554 October 1, 2001 ©2001 by The Journal of Bone and Joint Surgery, Inc.

2. Figs. 1-A, 1-B, and 1-C Case 2. Glenn Lipton et al. J Bone Joint Surg Am 2001;83:1552- 1554 ©2001 by The Journal of Bone and Joint Surgery, Inc.

3. Magnetic resonance T1-weighted (Fig. 1-B) and T2-weighted (Fig. 1-C) images showing the oval expansile cyst in the spinal canal at the second, third, and fourth sacral levels. Glenn Lipton et al. J Bone Joint Surg Am 2001;83:1552- 1554 ©2001 by The Journal of Bone and Joint Surgery, Inc.

4. Magnetic resonance T1-weighted (Fig. 1-B) and T2-weighted (Fig. 1-C) images showing the oval expansile cyst in the spinal canal at the second, third, and fourth sacral levels. Glenn Lipton et al. J Bone Joint Surg Am 2001;83:1552- 1554 ©2001 by The Journal of Bone and Joint Surgery, Inc.