What is a “crankshaft phenomenon,” and when does it occur?
Crankshaft phenomenon occurs in a very young patient who undergoes a posterior spinal fusion for scoliosis. Although the back of the spine is fused, the front of the spine continues to grow causing the characteristic twisting of the fusion mass in crankshaft phenomenon. New more rigid instrumentation techniques using stronger screws and rods can sometimes overcome continued of the spine. If this is not possible, the front and back of the spine may need to be fused by performing an anterior and posterior spinal fusion.
