1. Kikuchi S, Hasue M. Radicular symptoms of lumbo-sacral spine: anatomic consideration. Tokyo: Kanehira; 1996.
2. Matsumoto M, Chiba K, Ishii K, et al. Surgical result for posterior decompression for extra foraminal stenosis associated with osteophytes of L5-S1 vertebral bodies (in Japanese). Rinsyou Seikei Geka. 2007;40(7):799–803.
3. Ando M, Tamaki T, Yoshida M. Diagnosis for lumbar foraminal stenosis using sensory nerve action potential (in Japanese). Orthop Surg Traumatol. 2008;51:299–307.
4. Macnab I. Negative disc explosion; an analysis of causes of nerve root involvement in sixty-eight patients. J Bone Joint Surg Am. 1971;53-A:891–903.
5. Burton CV, Kirkaldy-Willis WH, et al. Causes of failure of surgery on the lumbar spine. Clin Orthop Relat Res. 1981;157:191–9.