A 55-year-old man with rectal cancer underwent robotic surgery in lithotomy position for >12 hours. Post-operatively, his left calf was swollen, with focal painful “knot”. CK was 4,661 improving to 547 within 5 days, consistent with rhabdomyolysis without compartment syndrome, given a compressible calf. His pain became neuropathic with burning in the sole, worse with weightbearing.  

This case underscores the importance of EMG in localization, characterizing injury (axonal or demyelinating), prognosis for recovery.  The tibial neuropathy may improve due to the possibility of conduction block, rather than axonal injury; this correlates with intact strength on exam.  EMG must be strategic; it is less sensitive in the acute period due to the time needed for Wallerian degeneration to be measurable on needle EMG.  Despite careful padding and positioning, it is essential to recognize the risk, examine patients carefully, plan EMG for confirmation. The best risk mitigation is that of avoidance of prolonged surgery times.