the association of anesthetic method with developing back pain after lower extremity operations

background selection of anesthetic approach for lower extremity operations is often a controversial issue for anesthesiologists. objectives the aim of this study was to compare the incidence and severity of back pain between general and spinal anesthesia, and to find effective factors in developing postoperative back pain. patients and methods in a randomized clinical trail, 148 patients with elective lower extremity surgeries were randomly allocated into two groups of 74. the first group received general anesthesia and the second group underwent spinal anesthesia. the incidence of back pain was observed and documented. the severity of back pain was assessed at the first, fourth and eighth postoperative weeks by visual analogue scale. results the mean of patients' age was 35.50 ± 13.34 years. the incidence and mean of back pain severity among all participants were respectively 35.80% and 15.95% at the first week, 7.40% and 2.43% at the fourth week, and 1.4% and 0.27% at the eighth postoperative week. the incidence and mean of back pain severity in spinal group were respectively 39.2% and 18.11% at the first, 12.2% and 3.92% at the fourth, and 2.7% and 0.54% eighth postoperative weeks. in general anesthesia group, these figures were respectively 32.4% and 13.78% at the first week and 2.7% and 0.95% at the fourth postoperative week. no back pain was reported at the eighth postoperative week. the incidence and severity of back pain in the first week showed significant difference between the two groups, while the mean severity of back pain showed significant difference at the fourth week after operation. conclusions spinal anesthesia could be probably considered as the sole effective factor in the development of back pain after operation.