The cornell medical index is self-administered instrument that collects a large body of significant medical and psychiatric data. The original C. M. I. consists of 195 questions, but authors selected 60 questions from the original C. M. I. to simplify it. The purpose of this investigation is to clarify if there are any correlations between low back pain and extraskeletal disorders. This investigation was conducted on 144 in-and out-patients who were treated at the Department of Orthopaedic Surgery,Our Lady of Mercy Hospital, Catholic Medical College from Jan. to July 1977. Among them 75 patients were male,69 patients were female, and 22 patients had decompression laminectomy and discectomy. The results of this investigation are as follows; 1. The majority of patients with low back pain are 2nd to 4th decade. (Male: 30±10.7) (Femal:36.1±10.5) 2. Average number of complaints is 19.9/60 in male, 21.8/60 in female. 3. Complaints in section F(Fatigability) and G(mental) are predominant in all cases. 4. There are no significant difference in number of complaints between the operative and non-operative case, and between each decade.