This animation compares the normal flexion and extension of the hip joint and flexion and extension following lumbar fusion surgery with screws placed bilaterally at the L4-L5 facet joints. Anatomy highlighted in this animation includes the pelvis and lumbar spine (L3-L5). Normally, the pelvis tilts as the leg is raised and lowered. Following surgery, the pelvis is not allowed to tilt due to the lumbar fusion and therefore the pelvis remains in a neutral position as the leg is raised and lowered.
