title: Positions for percutaneous nephrolithotomy: Thirty-five years of evolution.
abstract: OBJECTIVE
  To present the chronological development of the different positions described for percutaneous nephrolithotomy (PCNL), in an attempt to identify the reasons for their development and to highlight their specific advantages and disadvantages.
  
  
  METHODS
  Previous reports were identified by a non-systematic search of Medline and Scopus.
  
  
  RESULTS
  The classic prone position for PCNL was first described in 1976. The technique was gradually standardised and PCNL with the patient prone became the generally accepted standard approach. In the next 35 years many other positions were described, with the patient placed prone, lateral or supine in various modifications. Modifications of the classic prone position in the early 1990s aimed to provide the option of a simultaneous retrograde approach during the procedure. As PCNL became more popular the lateral position was first described in 1994, to allow the application of PCNL to patients who were unable to tolerate being prone because of their body habitus. The supine position for percutaneous access was originally described even before 1990, but become more popular after 2007 when the Galdakao modification was reported. Several other modifications of the supine position have been described, with the latest being the flank-free modified supine position, which allows the best exposure of the flank among the supine positions. Each position has its specific advantages and disadvantages.
  
  
  CONCLUSIONS
  Urologists who perform PCNL should be familiar with the differences in the positions and be able to use the method appropriate to each case.
authors.affiliation: Endourology and Stone Services, Barts Health NHS Trust, London, UK.
authors.forename: Theocharis
authors.initials: T
authors.lastname: Karaolides
authors.affiliation: Endourology and Stone Services, Barts Health NHS Trust, London, UK ; The Corfu Center of Endourology & Stone Services, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Moraitis
authors.affiliation: Endourology and Stone Services, Barts Health NHS Trust, London, UK.
authors.forename: Christian
authors.initials: C
authors.lastname: Bach
authors.affiliation: Endourology and Stone Services, Barts Health NHS Trust, London, UK.
authors.forename: Junaid
authors.initials: J
authors.lastname: Masood
authors.affiliation: Endourology and Stone Services, Barts Health NHS Trust, London, UK.
authors.forename: Noor
authors.initials: N
authors.lastname: Buchholz
keywords: Endoscopic intrarenal surgery; Flank; Lateral; PCNL; PCNL, percutaneous nephrolithotomy; Perctutaneous nephrolithotomy; Positions; Prone; Supine