In this prospective analysis the authors describe the clinical results of surgical treatment in patients > 80 years of age in whom spinal function was evaluated with motor evoked potential (MEPs) monitoring.
The authors included 57 patients > 80 years of age who were suspected of having cervical myelopathy. The mean age of the patients was 83.0 years (range 80–90 years). The central motor conduction time (CMCT) was calculated from the latencies of the MEPs following transcranial magnetic stimulation and from M and F waves following peripheral nerve stimulation.
Preoperative electrophysiological evaluation demonstrated significant elongation of CMCT or abnormalities in MEP waveforms in 37 patients (65%), and 35 patients of these underwent laminoplasty. In 30 patients cervical spondylotic myelopathy was diagnosed and 5 patients ossification of the posterior longitudinal ligament was diagnosed. The preoperative mean Japanese Orthopaedic Association Scale score was 8.6 (range 3–12.5) and the mean postoperative score was 12.6 (range 6–14.5) with an average recovery rate of 45% (range −21 to 100%). There were no major complications in any of the patients during the operative period and there were no cases of death resulting from operative intervention.
Sufficient clinical results are expected even in patients with myelopathy who are older than 80 years of age, provided the patients are correctly selected by electrophysiological evaluation with MEPs and CMCT.
Abbreviations used in this paper: ASA = American Society of Anesthesiologists; CMCT = central motor conduction time; JOA = Japanese Orthopaedic Association; MEP = motor evoked potential; RR = recovery rate; TMS = transcranial magnetic stimulation.
Address correspondence to: Nobuhiro Tanaka, M.D., Department of Orthopaedic Surgery, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan. email:firstname.lastname@example.org.
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