OBJECTIVE: Degenerative spinal conditions often result in positive sagittal alignment which may be corrected using multi-segment spinal reconstructive surgeries. The purpose of this study was to investigate gait kinematics before and after spinal reconstructive surgery in persons with positive sagittal alignment. METHODS: Subjects presenting with positive sagittal alignment of greater than or equal to 7 cm who were treated with spinal reconstructive surgery were included in this study. Gait analyses were conducted pre- and 6 months post-operatively. Data were collected while subjects stood quietly for 20s and walked at their normal self-selected walking speed. RESULTS: For 12 subjects, sagittal spine alignment during standing and walking was significantly decreased post-operatively (p<0.0001 for standing and p<0.0005 for walking). Prior to surgery, the subjects appeared to adopt a crouch gait with the knee flexion angle at mid terminal stance decreasing significantly after surgery (p<0.0 for the dominant lower limb and p<0.0 for the non-dominant lower limb). Additionally, dominant step length (p<0.003) and non-dominant step length (p<0.001) increased significantly after surgery. CONCLUSIONS: Positive sagittal alignment resulted in crouch gait, which was resolved after multi-segment reconstructive spinal surgery that improved sagittal spinal alignment. Step and stride lengths also improved after surgical correction of the sagittal alignment.