This systematic review aimed to describe the course of acute low back pain and sciatica and to identify clinically important prognostic factors. The review included 15 studies with variable methodological quality. Key findings include rapid improvements in pain (mean reduction of 58% of initial scores), disability (58%), and return to work (82% of those initially off work) within one month. Further improvement was observed until about three months, after which levels remained nearly constant. Approximately 73% of patients experienced at least one recurrence within 12 months. The review also identified a clinically useful predictor of return to work, which was the Vermont disability prediction questionnaire score of 0.48 or more. However, the low prevalence of failure to return to work at three months (pooled estimate of 6%) limits the clinical utility of this predictor. The review highlights that while most people with acute low back pain and associated disability improve rapidly within weeks, pain and disability are typically ongoing, and recurrences are common.This systematic review aimed to describe the course of acute low back pain and sciatica and to identify clinically important prognostic factors. The review included 15 studies with variable methodological quality. Key findings include rapid improvements in pain (mean reduction of 58% of initial scores), disability (58%), and return to work (82% of those initially off work) within one month. Further improvement was observed until about three months, after which levels remained nearly constant. Approximately 73% of patients experienced at least one recurrence within 12 months. The review also identified a clinically useful predictor of return to work, which was the Vermont disability prediction questionnaire score of 0.48 or more. However, the low prevalence of failure to return to work at three months (pooled estimate of 6%) limits the clinical utility of this predictor. The review highlights that while most people with acute low back pain and associated disability improve rapidly within weeks, pain and disability are typically ongoing, and recurrences are common.