Abstract: A system for dynamically adjusting treatment angle under tension to accommodate variations in spinal morphology during spinal decompression therapy is provided. It provides a tensioning device including a patient-positioning means, a tension-producing actuator, a positioning device, a patient interface device, a control system and a display. The control system with feedback on the resultant tension vector applied to patient spine operationally configured to allow for adjustment of either tension producing actuator position, patient position, or both while applying tension to the patient spine during non-therapeutic tension levels. The control system automatically adjusts tension producing actuator work levels such that the resultant tension vector magnitude remains ideally constant during adjustment of resultant tension vector angle, reducing the risk of eliciting paraspinal muscle contraction due to changes in resultant tension vector magnitude.