Comparison of supine and prone mini percutaneous nephrolithotomy in obese patients: a retrospective study

To compare the safety and effectiveness of Mini Percutaneous Nephrolithotomy (m-PNL) operations performed in the supine and prone positions in obese patients.

We retrospectively analysed data from obese patients (BMI ≥ 30) who underwent prone or supine mPCNL between January 2014 and June 2021 in our clinic. Kidney anomalies, coagulopathy, solitary kidney, skeletal deformity, and patients under 18 were excluded. Outcomes measures included operation time, fluoroscopy time, duration of hospitalisation, stone-free rate, and complications classified by Clavien-Dindo. Statistical analysis was performed using SPSS version 26.

The study included 338 patients (100 supine, 238 prone). Supine mPCNL had a shorter mean operation time (89.6 vs. 100.3 minutes, p=0.001), fluoroscopy time, and duration of hospitalisation (60.7 vs. 112.0 hours, p=0.001). Overall complication rates were comparable, but major complications were higher in the prone group (p=0.041). Logistic regression identified stone size >25 mm and prone position as significant risk factors for major complications.

Supine and prone mPCNL are both effective for treating kidney stones in obese patients. Supine mPCNL offers benefits, such as shorter operation time, reduced radiation exposure, and fewer major complications. Careful monitoring is recommended for patients with high CCI scores or larger stones due to increased complication risks.