Fig. 5.

Surface EMG (sEMG) recordings from the left paraspinal muscle at L2 and load-cell data collected during the performance of the FCE lifting with flexed knees test. Panels a and c show data collected before the hardware removal surgery. Panels b and d show data collected after the surgery. The EMG recording before the lumbar hardware removal surgery shows a lower level of activity and a more modest amplitude modulation compared to the data collected after surgery. It is worth noticing that Panels a and b show three bursts of EMG activity associated with the lifting task and a fourth burst of activity associated with returning to the upright position