BACKGROUND 
Paralysis of foot is one of the complication after combined spinal-epidural anaesthesia (CSEA). Incidence of this complication was reported about up to 20% after caesarean section (C/S). However, there were no study about predictors of these problems. We performed a multivariate logistic regression on pregnant woman with C/S to evaluate the relationship between predictors and paralysis of foot after C/S under CSEA.
METHODS
Data were obtained retrospectively from the medical and anaesthetic records of 291 pregnant woman with C/S under CSEA between January 1, 2011 and December 31, 2012 at Itabashi Chuo Medical Center. Paralysis of foot was defined as patients could not walk or bend theirs knee more than 90 degrees within 48 hours after C/S. Logistic regression was used to examine associations between the independent variable (i.e. paralyze or numbness of foot) and 14 parameters including patients, anaesthesia, and operative factors. A forward stepwise procedure was used to select the final regression model, which was determined by selecting the model with the lowest Akaike’s information criterion value for each step. 
RESULTS 
The incidence of paralysis of foot was 29.6% (86 of 291 patients). Multiple regression analysis revealed that gestation age, pregnancy induced hypertension, drug type of spinal anaesthesia, site and methods (median or paramedian) of epidural catheter insertion were associated with the incidence of paralysis of foot. Out of these, site of epidural catheter insertion (-0.0712 [95% confidence interval {CI}, -0.121 – -0.0218]) and paramedian method (0.230 [95%CI, 0.988 – 0.361]) were identified as strong predictors.
CONCLUSION
This study revealed that paralysis of foot after C/S under CSEA was affected by gestation age, pregnancy induced hypertension, drug type of spinal anaesthesia, site and methods of epidural catheter insertion.

Predictive factors associated with postoperative paralysis of foot after caesarean section under combined spinal-epidural anaesthesia: a retrospective study