Abstract
Neuralgia of the saphenous nerve (SN) is a rare clinical syndrome simulating a vascular disorder of the lower extremities. In four cases, the presenting complaint was persistent pain on the medial aspect of the knee. Examination revealed tenderness over the site of exit of the SN form the femoral canal. Femoral nerve motor conduction, quadriceps H-reflex and EMG of the leg muscles were normal. The sensory nerve action potential of the SN in the leg was not obtained in some patients, even in the unaffected leg. SEP were therefore preferred for diagnosis and performed at the infrapatellar and descending branches of the right and left SN and recordings from the Cz'-Fz electrode. Latency and amplitude differences were evaluated and compared with a control group of healthy subjects. An alteration in the SEP from one branch was observed on the painful side. Posterior tibial responses were normal. In one case, pain resolved immediately after neurolysis, confirming SN entrapment above the femoral canal, before its division. Pain resolved in two other cases and persisted in the last after medical treatment. SEP studies are valuable in the diagnosis of an isolated lesion of the SN.
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- Arthornthurasook A., Gaew-Im K. Study of the infrapatellar nerve. Am J Sports Med. 1988 Jan-Feb;16(1):57–59. doi: 10.1177/036354658801600110. [DOI] [PubMed] [Google Scholar]
- Arthornthurasook A., Gaew-Im K. The sartorial nerve: its relationship to the medial aspect of the knee. Am J Sports Med. 1990 Jan-Feb;18(1):41–42. doi: 10.1177/036354659001800107. [DOI] [PubMed] [Google Scholar]
- Eisen A., Elleker G. Sensory nerve stimulation and evoked cerebral potentials. Neurology. 1980 Oct;30(10):1097–1105. doi: 10.1212/wnl.30.10.1097. [DOI] [PubMed] [Google Scholar]
- Mozes M., Ouaknine G., Nathan H. Saphenous nerve entrapment simulating vascular disorder. Surgery. 1975 Feb;77(2):299–303. [PubMed] [Google Scholar]
- Ochoa J. L., Torebjörk H. E. Paraesthesiae from ectopic impulse generation in human sensory nerves. Brain. 1980 Dec;103(4):835–853. doi: 10.1093/brain/103.4.835. [DOI] [PubMed] [Google Scholar]
- Romanoff M. E., Cory P. C., Jr, Kalenak A., Keyser G. C., Marshall W. K. Saphenous nerve entrapment at the adductor canal. Am J Sports Med. 1989 Jul-Aug;17(4):478–481. doi: 10.1177/036354658901700405. [DOI] [PubMed] [Google Scholar]
- Synek V. M., Cowan J. C. Saphenous nerve evoked potentials and the assessment of intraabdominal lesions of the femoral nerve. Muscle Nerve. 1983 Jul-Aug;6(6):453–456. doi: 10.1002/mus.880060610. [DOI] [PubMed] [Google Scholar]
- Vogel P., Vogel H. Somatosensory cortical potentials evoked by stimulation of leg nerves: analysis of normal values and variability; diagnostic significance. J Neurol. 1982;228(2):97–111. doi: 10.1007/BF00313755. [DOI] [PubMed] [Google Scholar]
- Wainapel S. F., Kim D. J., Ebel A. Conduction studies of the saphenous nerve in healthy subjects. Arch Phys Med Rehabil. 1978 Jul;59(7):316–319. [PubMed] [Google Scholar]
- Worth R. M., Kettelkamp D. B., Defalque R. J., Duane K. U. Saphenous nerve entrapment. A cause of medial knee pain. Am J Sports Med. 1984 Jan-Feb;12(1):80–81. doi: 10.1177/036354658401200114. [DOI] [PubMed] [Google Scholar]