An Investigation of the Relationship between Anthropometry (Height, Weight and Body Mass Index) and Incidence of Low Back Pain Following Spinal Anesthesia in Elective and Emergency Surgical Procedures

Background: The incidence of low back pain in adults after spinal anesthesia is rather similar to that of general anesthesia. The pain is often mild with an increased incidence of low back pain that rarely spreads to the lower extremities but persists for several days after surgery. Fear of complications of back pain after neuraxial injection is one the main reason for patient’s refusal of neuraxial anesthesia. Some studies repoted obesity and BMI above 32 as risk factors for low back pain after surgery. In this study, we aimed to investigate the relationship between selected parameters of body composition, including the amount of total body fat and muscular tissue, and the incidence of low back pain after spinal anesthesia. Methods: A cross-sectional study was carried out on 100 patients who were candidates for elective or emergency surgery under spinal anesthesia. At first demographic data, a history of back pain and assessment and anthropometric assessment was asked. The history of back pain and intensity of pain were asked after one day, one month and 4 months after surgery. Then the relationship between pain intensity and anthropometric data were assessed. Results: The mean pain intensity in the normal weight group was 1.3 ± 0.63. In the overweight group, the mean pain intensity was 1.1 ± 0.41. In the obese group, the mean pain intensity was 2.2± 1.2. Regarding the relationship between mean pain intensity and weight, BMI, and anthropometry, the incidence of pain was not related to patients' anthropometry; the mean pain intensity of these groups were compared; and the incidence of pain was not dependent on weight, BMI, and anthropometry (p-value= 0.4). Conclusion: Based on the obtained results, it can be concluded that no correlation exists between the incidence of low back pain and mean severity of pain and anthropometric indicators such as BMI, however, low back pain lasted longer in obese patients, which requires further study to investigate the exact nature of such a relationship.