Ba Ji Tian (Morinda officinalis) is a traditional herb widely used in Chinese medicine, especially for musculoskeletal complaints such as backache and weakness of the lower back and knees. In traditional Chinese medicine (TCM), Ba Ji Tian is categorized as a yang tonic, meaning it is used to "tonify the kidney yang" — a concept believed to be closely associated with strength, vitality, and the health of the lower back. Classical texts and modern TCM practitioners recommend Ba Ji Tian in herbal formulas for individuals experiencing back pain, often attributed to kidney yang deficiency.

From a scientific perspective, there is limited evidence supporting its efficacy specifically for backache. Some animal studies suggest that extracts of Ba Ji Tian may have anti-inflammatory and analgesic effects, which could theoretically help with pain, including backache. However, robust clinical trials in humans are lacking, and the exact mechanisms remain unclear. Reviews of the available literature indicate that while Ba Ji Tian has promising biological activities, its use for backache is still mainly justified by traditional practice rather than by direct scientific validation.

In summary, Ba Ji Tian’s use for backache is rooted in traditional medical theory rather than strong scientific evidence. While some preclinical research hints at possible benefits, the level of evidence is modest, meriting a rating of 2 out of 5.