Comparative Effectiveness of Shockwave Lithotripsy vs. Ureteroscopy for Lower Pole Kidney Stones

Abstract

Introduction: Lower pole kidney stones are challenging to clear due to gravity-dependent anatomy. Extracorporeal shockwave lithotripsy (SWL) is less invasive than ureteroscopy (URS), but stone-free rates (SFR) may be lower. This review compares outcomes for lower pole calculi.

Methods: We searched MEDLINE, Embase, and Cochrane Library (2010–2024) for RCTs and high-quality cohort studies comparing SWL versus URS for lower pole stones ≤20 mm. Primary outcome: SFR at 3 months (no residual fragments ≥3 mm). Secondary: retreatment rate and complications.

Results: Ten RCTs (n=1,416) and 8 cohorts (n=2,103) were analyzed. For stones ≤10 mm, SFR favored URS (87% vs. 75%, RR 1.16, p<0.01). For 11–20 mm, difference widened (URS 82% vs. SWL 58%, RR 1.41). SWL had lower retreatment rate for ≤10 mm stones (12% vs. 6% for URS? actual: SWL retreatment 24% vs URS 8%, p<0.01). Complication rates (Clavien ≥2) were similar (9% SWL vs. 11% URS).

Discussion: URS achieves higher SFR for all lower pole stone sizes, at the cost of general anesthesia and stent placement. SWL is acceptable for ≤10 mm non-dense stones. Most studies excluded obese patients, limiting applicability.

Conclusions: For lower pole stones >10 mm, ureteroscopy is superior. For stones ≤10 mm, patient choice after informed discussion of trade-offs is appropriate. Shockwave lithotripsy remains an option for those avoiding invasive procedures.