Anterior or posterior SWL in proximal ureteral stones opposite to 4th and 5th lumbar vertebrae?

Background Results of SWL in treatment of upper ureteral calculi are conflicting which is definitely affected by stone locations along the proximal ureter, which is may be due to the more deep and medial course of the ureter distally over the thick and strong abdominal back wall which may hinder shock waves. Methodology One hundred patients with radiopaque proximal ureteral stone opposite 4th and 5th lumbar vertebrae who had SWL were randomized into two groups. First group had SWL through anterior belly wall in supine position with countertraction, the second group had standard posterior SWL. Patient's demographics and stone characters were evaluated assessing stone burden and calculating S.T.O.N.E score. Patients were followed up to assess stone-free rate using serial digital plain X-ray KUB. Results Anterior approach needed less power to reach SFR ( p = 0.05) in less number of sessions where 90% of cases in anterior group had only one session to reach SFR versus 52% in posterior group ( p = 0.001). Also, post-SWL pain, hematuria, obstruction and infection were significantly less in anterior group ( p = 0.005). Although patients who had anterior approach showed statistically significant shorter time to stone expulsion. SFR does not differed significantly between study groups ( p = 0.02). On further analysis; anterior SWL had a better chance to reach SFR (HR = 1.6, p = 0.001). Conclusion It seems that anterior SWL approach in supine position is safe and effective especially in mild obese patient with floppy abdomen. Patients who had anterior SWL approach had a better chance to achieve stone-free rate.