Comparison of the prone split-leg position (PSL) with the traditional prone position (TP) in percutaneous nephrolithotomy: a propensity score- matching study.

BACKGROUND AND OBJECTIVE Several positions have been described for percutaneous nephrolithotomy (PCNL). The aim of this study was to compare the safety and effectiveness of the traditional prone position PCNL (TP-PCNL) and the prone split-leg position (PSL). PATIENTS AND METHODS A retrospective review was made of the data of 212 patients who underwent prone PCNL in PSL or TP position between January 2017 and November 2019. The demographic and preoperative clinical data were used for propensity score-matching (PSM). Following the PSM based on a multivariable logistic regression model, the PSL-PCNL and TP-PCNL groups were compared in preoperative, perioperative and postoperative parameters. All surgical procedures were performed by an experienced endourologist. RESULTS After PSM, 51 patients from the PSL-PCNL group were matched to 51 TP-PCNL patients. The stone burden was not statistically significant between the two groups (p = 0.388). The mean operation time of the two groups was significantly different (81.5±32.4 mins vs 93.1±25.9 mins, respectively, p=0.026). The hemoglobin decrease in the PSL-PCNL group was greater than that in the TP-PCNL group (-17.7±16.9 vs 13.1±10.9 g/L, p <0.001). Both groups had similar stone free rates after 2 weeks (p = 0.49). No significant difference was observed between the groups in the total complication rate (p = 1). CONCLUSIONS The application of PSL in PCNL simplifies the surgical procedure and shortens the operating time. Another important advantage is that it allows RIRS (retrograde intrarenal surgery) and ureteroscopy to be performed simultaneously. We recommend the prone split-leg position to be applied in percutaneous nephrolithotomy for renal stone patients.