Osteoanabolic drugs are sometimes prescribed off-label for "fracture healing and spinal fusion." This study examines the scientific validity of such practices by analyzing existing clinical reports. The purported bone union-promoting effect of teriparatide in fracture cases has been refuted in clinical trials. While teriparatide shows efficacy in accelerating spinal fusion after surgery for patients with osteoporosis, there is no scientific justification for its off-label use in patients without osteoporosis. For osteoporosis patients, no clear evidence suggests that teriparatide is superior to antiresorptive drugs, making the rationale for switching from antiresorptive drugs to teriparatide weak. The efficacy in postoperative spinal fusion may primarily be attributed to systemic improvements in bone quality and quantity, enhancing the mechanical engagement of implants. The clinical evidence for the off-label use of romosozumab, another osteoanabolic drug, in fracture healing and spinal fusion is insufficient to support its efficacy. In conclusion, osteoanabolic drugs, like antiresorptive drugs, primarily have systemic functions in osteoporosis patients, with limited evidence supporting their role in promoting localized bone formation in fractures or spinal fusions.