On 03/18, EE reported that EE was having back pain that potentially stemmed from a task EE performed on 03/11. On the evening of 03/11, the employee was using a metal rod to clear debris from a bin level sensor. Employee states pain was minor starting on 03/12 but worsened to the point of reporting on 03/18. Incident reclassified to Recordable on 03/20 after visiting clinic.