This retrospective clinical study presents pyeloplasty results following a muscle-splitting dissection, with mini-flank incision, using instruments held in a vertical position. Between 2004 and 2010, dismembered pyeloplasty (Anderson-Hynes) was performed in 37 cases (32 males and 5 females) with an average age of 26 years (range, 20-56 years). The technique was carried out through a window opened by separating the lateral abdominal muscles. Operation duration, length of incision, postoperative pain, complications, and radiological and clinical results were discussed. The operation duration was between 50 and 90 minutes (average = 65 minutes), the incisional length 5 and 7 cm (average = 5.2 cm), and visual pain scale was 4.1 +/- 3.1 and 3.3 +/- 3.4 at 4 and 24 hours after the operation, respectively. The duration of hospitalization was between 30 and 120 hours (average = 42 hours). In a retrospective analysis of our study, one case was reoperated on, following recurrence with obstruction, there were 9 cases with prolonged dilation in response to diuretics and 29 cases with complete recovery. Pyeloplasty operations, with a vertical surgical approach through smaller incisions and muscle separation, offered shorter periods of hospitalization, less postoperative pain, acceptable cosmetic results and higher rates of functional recovery. Copyright (C) 2011, Elsevier Taiwan LLC. All rights reserved.