Bed break-induced attenuation of downside leg sciatic nerve sensory and motor evoked potentials during lateral lumbar interbody (LLIF) fusion surgery.
Downside leg sciatic nerve monitoring alerts during lateral lumbar interbody fusion were uncommon and not followed by postoperative deficits.
Bed break-induced attenuation of downside leg sciatic nerve sensory and motor evoked potentials during lateral lumbar interbody (LLIF) fusion surgery.
Multimodality intraoperative neuromonitoring (intraoperative neuromonitoring) is used to map and monitor the femoral plexus during transpsoas lateral lumbar interbody fusion (lateral lumbar interbody fusion) surgery.
A single-center 30-month retrospective examined the frequency of downside leg sciatic nerve distribution intraoperative neuromonitoring alerts for 692 patients, 380 female (55%) and 312 male (45%), having lateral lumbar interbody fusion spine surgery utilizing intraoperative neuromonitoring consisting of SSEPs, TcMEPs, TaMEPs, electromyography (electromyography) and electroencephalography (electroencephalography).
No cases detected concomitant intraoperative neuromonitoring changes involving downside-leg femoral nerve distribution.
Of the 18 alerts, 17 occurred in females, 12 in females with BMI ≥ 30, and 16 in patients aged 60 or older.
Chi-square analysis points to sex (female) and obesity (BMI ≥ 30) as characteristics that correlate to this phenomenon.
Interestingly, none of the 18 patients, including the 2 where intraoperative neuromonitoring responses did not return to baseline, suffered postoperative downside leg sciatic distribution motor or sensory deficits.
The possible mechanism of these downside leg alerts is compression or stretch of the sciatic nerve at the level of the pelvis, not leg ischemia.
While none of the 18 alert case patients suffered postoperative deficits, best practice would be to partially or completely unbreak the bed as soon as feasible when the downside sciatic nerve distribution intraoperative neuromonitoring signals are attenuated.