No radiographs for muscle spasm CMAJ 1998;158:170 Although there may be medicolegal reasons for ordering neck and back radiographs in the emergency room after trauma, as suggested by Dr. Raymond Shanderain in his letter, "Ordering radiographs with the law in mind" (CMAJ 1997;157[10]:1352 [full text]), the detection of muscle spasm is not one of them. Muscle spasm in this situation is a myth, both clinically and radiologically. In up to 42% of normal subjects radiography reveals a straight cervical spine. Thus, the observed spinal alignment on the radiograph may represent the subject's posture at the time the image was obtained, a normal anatomic variant or the positioning of the subject by the technician.1,2 As for the physical examination, muscle spasm is neither a valid nor a reliable physical sign. Nothing in the medical literature proves that muscle spasm in the neck or back can be diagnosed clinically with any precision by superficially touching the skin. Tenderness to palpation is an unreliable sign,3 one that has never been correlated with a gold standard for muscle spasm. "Attempts to objectify muscle spasm have not been rewarding. Needle electromyography has shown that areas of muscle tenderness are electrically silent."4 Perry Rush, MD North York, Ont. 70446.14@compuserve.com References Helliwell PS, Evans PF, Wright V. The straight cervical spine: Does it indicate muscle spasm? J Bone Joint Surg Br 1994;76:103-6. Weir DC. Roentgenographic signs of cervical injury. Clin Orthop 1975;109:6-17. McCombe PF, Fairbank JCT, Cockersole BC. Reproducibility of physical signs in low-back pain. Spine 1989;21:908-18. Demeter SL, Andersson GBJ, Smith GM. Disability evaluation. St. Louis: Mosby-Year Book; 1996. p. 447. Send a letter to the editor responding to this letter Envoyez une lettre à la rédaction au sujet de cette lettre | CMAJ January 27, 1998 (vol 158, no 2) / JAMC le 27 janvier 1998 (vol 158, no 2) |