Efficacy of corticosomatosensory evoked potential monitoring in predicting and/or preventing sciatic nerve palsy during total hip arthroplasty.

Sciatic nerve palsy (SNP) is one of the most distressing complications associated with total hip arthroplasty. The authors used corticosomatosensory evoked potential monitoring in 290 consecutive patients in an attempt to predict when SNP might occur and to prevent its occurrence by changing the position of the retractors and/or the operated limb in response to intraoperative waveform changes. Despite these efforts there were 8 SNPs among the 290 patients (2.8%). The authors compared this group with 485 consecutive patients who were not monitored. In the latter group there were 13 SNPs (2.7%). There were two monitored patients (0.7%) with no intraoperative evidence of SNP who exhibited SNP after surgery (false negatives). Corticosomatosensory evoked potential monitoring was found to be neither effective in predicting SNP nor helpful in its prevention.