To establish the efficacy of nephrolithotripsy via intercostal access route vs subcostal access route with respect to attained stone-free status, operating time, and complications.

Percutaneous nephrolithotripsies via the upper pole were performed in 142 patients (93 male, 49 female, age 24-78 years) from 1998 to 2005 at our 4 academic medical centers. Selection criteria for nephrolithotripsy via upper pole access were staghorn calculi ≥5.5 cm³, upper pole calyx calculi ≥2.5 cm, and abnormal or high lying kidney, often in combination with obesity. Of 68 staghorn calculi, 49 were accessed via intercostal and 19 via subcostal route. Of 57 upper calyx calculi 38 were accessed via intercostal and 19 via subcostal route; all calculi in the upper ureter considered easily accessible via the intercostal route.

Of 103 patients with intercostal access, 91 attained a stone-free status. There were 4 major and 6 minor complications. Depending on stone location, mean operating times varied from 42 to 152 minutes. Of 39 patients in whom a subcostal access route was chosen, 29 were made stone-free. There were 3 major and 8 minor complications. The mean operating time varied from 108 to 145 minutes.

The significantly higher rate of achieving stone-free status, lower rate of complications, and markedly reduced operating time when using intercostal access make this the route of choice for upper pole nephrolithotripsy.