Chronic low back pain, typically managed through lumbar fusion, demands innovative approaches to enhance therapeutic outcomes. This study investigates the efficacy of small extracellular vesicles (sEVs) derived from bone marrow mesenchymal stem cells (BMSCs) cultured in three-dimensional (3D) scaffolds concurrently under electromagnetic fields (EMF) stimulation, aiming to enhance osteogenesis and angiogenesis in a rat lumbar fusion model. We utilize a composite of polycaprolactone and hydroxyapatite, engineered via 3D printing, to create the scaffolds. sEVs are harvested from BMSCs under three distinct conditions: standard 2D cultures, 3D scaffolds, and 3D scaffolds with EMF stimulation. Specifically, the sEVs from the EMF-stimulated 3D cultures (3D/E-sEVs) are incorporated into these scaffolds before being implanted into rat spines. Results reveal that 3D/E-sEVs markedly enhance both osteogenesis and angiogenesis. Further mechanistic investigations identify the PTEN/PI3K/AKT signalling pathway as essential in mediating these regenerative effects. Moreover, 3D PCL/HA scaffold loaded with 3D/E-sEVs promote lumbar fusion in a rat model. Conclusively, our findings demonstrate that 3D-printed PCL/HA scaffolds engineered with 3D/E-sEVs significantly promote bone regeneration and vascular formation, thereby improving lumbar fusion outcomes. This study highlights potential of integrating tissue engineering techniques with sEVs therapies to revolutionize the treatment of low back pain and enhance surgical success rates.