Abstract
Conjoined lumbosacral nerve roots (CLNR) are the most common anomalies involving the lumbar nerve structures which can be one of the origins of failed back syndromes. They can cause sciatica even without the presence of a additional compressive impingement (such as disc herniation, spondylolisthesis or lateral recess stenosis), and often congenital lumbosacral spine anomalies (such as bony defects) are present at the “conjoined sheaths”. This congenital anomaly has been reported in 14% of cadaver studies, but myelographic or computed tomographic studies have revealed an incidence of approximately 4% only. Diagnostic methods such as magnetic resonance imaging (MRI) are helpful for determination of the exact anatomical relations in this context. We present five typical cases of conjoined nerve roots observed during a 1 year period, equivalent to 6% of our out-patients without a history of surgical treatment on the lumbar spine. In all cases with suspicious radiological findings MRI or lumbar myelography combined with CT and multiplanar reconstructions is recommended.
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References
Agnoli AL (1976) Anormale Wurzelabgänge im lumbosacralen Bereich und ihre klinische Bedeutung. J Neurol 211:217–228
Bouchard JM, Copty M, Langelier R (1978) Preoperative diagnosis of conjoined root anomaly with herniated lumbar discs. Surg Neurol 10:229–231
Cail WS, Butler AB (1983) Conjoined lumbosacral nerve roots. Diagnosis with metrizamide myelography. Surg Neurol 20:113–119
Cannon BW, Hunter SE, Picaza JA (1962) Nerve root anomalies in lumbar disc surgery. J Neurosurg 19:208–214
Epstein JA, Carras R, Ferrar J, Hyman R, Khan A (1981) Conjoined lumbosacral nerve root. Management of herniated discs and lateral recess stenosis in patients with this anomaly. J Neurosurg 55:585–589
Ethelberg S, Riishede J (1952) Malformation of lumbar spinal roots and sheaths in the causation of low backache and sciatica. J Bone Joint Surg Br 34:442–446
Gado MH, Hodges FJ, Patel JI (1982) In: Lee JT, Sagel SS, Stanley RJ (eds) Computerized body tomography. Raven, New York
Gomez JG, Dickey JW, Bachow TB (1993) Conjoined lumbosacral nerve roots. Acta Neurochir 120:155–158
Helms CA, Dortwart RH, Gray M (1982) The CT appearance of conjoined nerve roots and differentiation from herniated nucleus pulposus. Radiology 144:803–807
Hoddick WK, Helms CA (1985) Bony spinal canal changes that differentiate conjoined nerve roots from herniated nucleus pulposus. Radiology 154:119–120
Kaddish L, Simmons E (1984) Anomalies of the lumbosacral nerve roots. An anatomical investigation of myelographic study. J Bone Joint Surg Br 66:411–416
Keon-Cohen B (1968) Abnormal arrangement of the lower lumbar and first sacral nerves within the spinal canal. J Bone Joint Surg Br 50:261–265
Langlotz M (1986) Lumbar myelography with water-soluble contrast media. Textbook and atlas including comparison with computed tomography. Thieme, Stuttgart
Neidre A, MacNab I (1983) Anomalies of the lumbosacral nerve roots. Review of 16 cases and classification. Spine 8:294–299
Ogon M, Goebel WE, Trappe AE (1991) Rezidivierende Ischialgien durch “conjoined nerve roots”. Diagnostik, Therapie, Verlauf. Nervenarzt 62:378–382
Okuwaki T, Kunogi J, Hasue M (1991) Conjoined nerve roots associated with lumbosacral spine anomalies. A case report. Spine 16:1347–1349
Pecker J, Simon J, Bon Salah A (1974) L’accolement en canon de fusil des racines rachidiennes, piege diagnostique. Nouv Pres Med 13:1155–1156
Peyster RG, Teplik JG, Haskin ME (1985) Computed tomography of lumbosacral conjoined nerve root anomalies. Potential cause of false positive reading for herniated nucleus pulposus. Spine 10:331–337
Rask MR (1977) Anomalous lumbosacral nerve roots associated with spondylolisthesis. Surg Neurol 8:139–140
Torricelli P, Spina V, Martinelli C (1987) CT diagnosis of lumbosacral conjoined nerve roots. Findings in 19 cases. Neuroradiology 29:374–379
Wöber G, Böck F (1971) Lumbale Nervenwurzelanomalien bei Ischialgien. Nervenarzt 42:552–555
Zagnoni C (1949) Reperto di un tipo non conosciuto di anastomosi nervosa delle radici spinali. Atti Soc Med Chir Padova 27:48–52
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Böttcher, J., Petrovitch, A., Sörös, P. et al. Conjoined lumbosacral nerve roots: current aspects of diagnosis. Eur Spine J 13, 147–151 (2004). https://doi.org/10.1007/s00586-003-0634-8
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DOI: https://doi.org/10.1007/s00586-003-0634-8