Supine versus prone percutaneous nephrolithotomy: A narrative and analytical review of technique

ABSTRACT

Introduction:

Percutaneous nephrolithotomy (PCNL) remains the gold standard for large and complex renal calculi. Although the prone position has traditionally been used since the introduction of PCNL in 1976, supine PCNL and its modifications have gained increasing acceptance with growing evidence supporting their efficacy and safety. This narrative review aims to compare supine and prone PCNL across various domains.

Methods:

Databases, PubMed/MEDLINE, Cochrane Library, Scopus, Web of Science, and Google Scholar were included. Priority was given to randomized-controlled trials, meta-analyses, and large prospective studies (>100 patients). Evidence was synthesized across operative, anesthetic, safety and technological domains.

Results:

Supine PCNL demonstrated stone-free rates comparable to prone PCNL. Multiple meta-analyses showed significantly shorter operative times (by 13–25 min), improved anesthetic safety, reduced radiation exposure, shorter learning curve, lower infectious complications, and superior ergonomics with the supine approach. Supine PCNL facilitates Endoscopic Combined Intrarenal Surgery and is particularly advantageous in obese, pediatric, elderly, and cardiovascular high-risk patients. Miniaturized PCNL techniques further enhance these benefits. Ultrasound-guided access contributes to improved procedural safety, whereas gravity-assisted drainage helps maintain low intrarenal pressure and facilitates gravity-assisted fragment evacuation. Emerging technologies such as vacuum-assisted systems and robotic-assisted PCNL appear inherently more compatible with the supine position.

Conclusion:

Supine PCNL offers significant operative, anesthetic, and technological advantages while maintaining equivalent stone-free outcomes. It can be considered an equally useful approach in most clinical scenarios, whereas prone PCNL has definite advantages in selected anatomical situations.

INTRODUCTION

Urolithiasis is one of the oldest documented diseases in human history and among the most prevalent in the modern world, with a global prevalence of 10%–15% in developed nations and a recurrence rate of 26% at 5 years.[1,2] Percutaneous nephrolithotomy (PCNL) is the cornerstone of surgical management for stones ≥20 mm, staghorn calculi, failed extracorporeal shockwave lithotripsy or ureteroscopy, and anatomically complex cases.[1,3] The debate about the preferred position, whether supine or prone, has been an active area of discussion in the endourology community, with meaningful implications for anesthetic safety, operative efficiency, training, and access to emerging technology.

The first percutaneous nephrostomy was performed by Goodwin et al. in 1955 for drainage of a hydronephrotic kidney.[4] The first deliberate percutaneous stone removal was achieved by Fernström and Johansson in Sweden in 1976, using stone grasping forceps and Dormia basket through a percutaneously created tract.[5] Alken et al. subsequently refined the technique, introducing sequential metal telescopic dilatation systems.[6] For more than two decades, the prone position was the uncontested standard PCNL position.

The paradigm shift began in 1998 when Valdivia Uría et al. published a landmark series of 557 patients treated in the supine position, reporting equivalent stone clearance and complication rates with the added advantages of eliminating patient repositioning and comfort to the patient.[7] Subsequent modifications proliferated: the Barts flank-free supine technique offered greater operative flexibility;[8] the Galdakao-modified Supine Valdivia (GMSV) position, introduced modified lithotomy with the ipsilateral leg extended and the contralateral leg in a stirrup, providing the platform for simultaneous antegrade and retrograde endoscopy;[9] and numerous institutional adaptations including oblique supine, lateral decubitus, the Calcutta position[10] and complete supine variants have been reported. By 2011, the Clinical Research Office of the Endourological Society published a registry study of 5803 PCNL procedures concluding that position choice should be tailored to patient characteristics and surgeon preference.[11] As of 2026, supine PCNL is an increasingly adopted technique in several leading European and Asian endourology centers, particularly those with high Endoscopic Combined Intrarenal Surgery (ECIRS) activity, and both European Association of Urology (EAU) and American Urological Association (AUA) guidelines acknowledge both positions without declaring a definitive preference.[1,3]

This narrative review aims to: (i) comprehensively compare supine and prone PCNL across all operative and perioperative domains; (ii) critically synthesise evidence from randomized controlled trials (RCTs), meta-analyses, and large prospective series published between 1998 and 2025; (iii) examine the interaction between patient positioning and emerging innovations including miniaturized PCNL, ultrasound guidance (UG), vacuum suction systems, and ECIRS; and (iv) provide evidence-based guidance for training, guideline development, and operative decision-making.

METHODS

A structured narrative literature search was performed using PubMed/MEDLINE, Cochrane CENTRAL, Scopus, Web of Science, and Google Scholar for English-language studies published between January 1976 and April 2026. Search terms included PCNL, supine, prone, ECIRS, mini-PCNL, UG PCNL, intrarenal pressure, urosepsis, and related keywords combined using Boolean operators. Additional references were identified through manual citation review. Data extracted from included studies comprised: stone-free rates (SFRs), operative time, complication rates (Clavien–Dindo classification), radiation exposure, length of hospital stay, anesthetic outcomes, and learning curve metrics. Priority was given to RCTs, systematic reviews, meta-analyses, and large cohort studies (>100 patients) comparing supine and prone PCNL, along with landmark technical descriptions. Case reports, conference presentations, editorial comments, and non-English language publications were excluded except for rare anatomical variants. The review adhered to the Scale for the Assessment of Narrative Review Articles framework for methodological transparency.[12]

Artificial intelligence disclosure

The authors declare that they have used Claude artificial intelligence for writing the manuscript and to create the analytical table. The authors confirm that they have reviewed the manuscript and take full responsibility for the contents in the article.

RESULTS

Position

Prone variants

The standard prone position places the patient face-down, with or without thoracoiliac supports. The major advantage is that it provides a large surface area for percutaneous renal access and a wide space for instrument manipulation. The prone hip-flexed modification improves flank exposure and is particularly useful in obese patients.[13]

Supine variants

A comparative study of 393 PCNL procedures showed no significant differences in SFR, hemoglobin drop, transfusion rate, or hospital stay among prone and various supine approaches, although GMSV provided greater procedural flexibility due to simultaneous retrograde access.[14] Major supine variants include:

1. Complete Supine (Valdivia, 1998): Supine with 20–30° flank elevation; facilitates simultaneous retrograde access but limits nephroscope mobility[7]

2. Barts Flank-free Supine: Ipsilateral arm crossed over the chest with flank beyond table edge, improving instrument maneuverability[8]

3. GMSV: Modified lithotomy with ipsilateral leg extended and contralateral leg abducted; considered the reference position for ECIRS[9]

4. Calcutta Position: The ipsilateral (surgical side) leg is extended flat on the table, whereas the contralateral leg is flexed and placed in a stirrup for simultaneous retrograde access[10]

5. Oblique Supine: Patient tilted 20°–45° laterally (ipsilateral side elevated, beyond the standard Valdivia flank roll, providing more direct posterior calyceal access), improving posterior calyceal access[15]

6. Lateral/Flank Position (not strictly supine; included as a non-prone alternative): Full lateral decubitus, useful in extreme obesity or contraindications to prone positioning, though with restricted instrument mobility.[16]

Overall, GMSV remains the standard supine platform for ECIRS, whereas position selection should be individualized according to stone complexity, patient factors, anesthesia considerations, and surgeon preference.

Anesthesia safety and perioperative management

Supine PCNL offers unrestricted airway and venous access, making intraoperative emergencies easier to manage. In contrast, repositioning during prone procedures following cardiac or anesthetic emergencies may require several minutes and can adversely affect outcomes.[17]

Prone positioning is associated with recognized neurological and musculoskeletal risks, including brachial plexus traction, ulnar and femoral nerve injuries, optic nerve ischemia, and cervical spine complications in susceptible patients; these risks are largely avoided in the supine position.[17,18]

Hemodynamic studies have shown greater fluid absorption, electrolyte disturbances, and cardiovascular variability with prone PCNL compared to supine PCNL.[19] Supine and lithotomy positions also provide better respiratory compliance and oxygenation, particularly beneficial in obese patients and those with obstructive lung disease.[20] An additional advantage of supine PCNL is the feasibility of performing the procedure entirely under regional anesthesia without repositioning. A 2024 study looking at upper-pole access during supine PCNL under spinal anesthesia reported 98% stone clearance without any anesthesia-related complications.[21] In contrast, prolonged prone PCNL usually requires general anesthesia with controlled ventilation.

Anatomical considerations and learning curve

Randomized trials have shown a shorter learning curve with supine PCNL. Bulut et al. reported that novice surgeons achieved a SFR plateau after 10 supine cases versus 40 prone cases,[22] whereas Sabaa et al. demonstrated faster reduction in fluoroscopy time and fewer access failures with the supine approach.[23] Birowo et al. further showed that proficiency in UG supine PCNL with Alken dilators could be achieved within 20 cases.[24] An RCT in flank-free modified supine PCNL found that biplanar fluoroscopic guidance significantly reduced puncture time and improved first-pass success compared with monoplanar guidance.[25] Although prone PCNL offers greater renal stability and easier posterior calyceal orientation, supine PCNL allows both anterior and posterior calyceal access with comparable safety, complication, and SFRs, as demonstrated by Ricapito et al.[26]

Mini percutaneous nephrolithotomy

The miniaturization of PCNL instrumentation from the standard 24-30F tract to mini-PCNL (14-22F), ultra-mini PCNL (11-14F), super-mini PCNL (14F with suction), and micro-PCNL (4.85F all-seeing needle) represents one of the most significant technological developments in contemporary urology.[27,28] These smaller tracts reduce bleeding, postoperative pain, and hospital stay at the cost of slower stone fragmentation and prolonged procedure time.

A prospective randomized study comparing ultramini PCNL in supine and prone position found that both positions are feasible, safe, and effective for the treatment of pediatric renal stones with relatively shorter operative time in supine position.[29] A study by Eryılmaz et al. compared pediatric mini-PCNL in supine and prone position and found no significant difference in SFR or complications between supine and prone mini-PCNL in children, but significantly shorter operative times and consequently less anesthesia exposure in the supine group.[30]

Suction and vacuum systems

De Stefano et al., in a systematic review on suction technology in PCNL, demonstrated that continuous negative-pressure suction sheaths reduce operative time, lower intrarenal pressure, and improve stone clearance by facilitating fragment evacuation without repeated irrigation.[31] In the prospective multicenter EAU Suction Mini-PCNL Collaborative Study, Castellani et al. reported improved ergonomics and lower complication rates with suction mini-PCNL in the supine position.[32] The combination of suction systems with supine PCNL appears advantageous, as gravity-assisted drainage together with active suction helps maintain very low intrarenal pressures and may reduce pyelovenous backflow.[31]

Ultrasound guided access

The adoption of UG for percutaneous renal access synergises with supine positioning. In a meta-analysis of 21 RCTs encompassing 2969 patients, Du et al. found no significant difference between UG-PCNL and fluoroscopy-guided PCNL (FG-PCNL) in SFR, overall complications, operative time, or hospital stay, whereas demonstrating significantly shorter radiation exposure time in the ultrasound group (P < 0.001).[33] A separate meta-analysis by Arabzadeh Bahri et al., incorporating 19 studies and 3016 patients, concluded that UG-PCNL provides the advantage of requiring less radiation exposure while being just as efficient as FG-PCNL.[34]

Zampini et al. demonstrated that UG and fluoroscopy-assisted supine PCNL was associated with a lower effective radiation dose compared with prone PCNL (2.92 ± 0.32 mSv vs. 5.3 ± 0.7 mSv, P = 0.0014), even when ultrasound supplemented rather than replaced fluoroscopy.[35] A randomized clinical trial by Falahatkar et al. comparing US-guided versus FG complete supine PCNL found equivalent SFR (88.5% vs. 75.5%, P = 0.16) with fewer complications in the US-guided group, confirming that total US guidance in supine PCNL is safe, reproducible, and radiation-free.[36] In pediatric mini-PCNL, replacing fluoroscopy with ultrasound-assisted guidance reduced radiation dose from 32.35 ± 13.79 mGy to 6.07 ± 3.57 mGy without compromising SFR.[37]

Intrarenal pressure and infectious complications

Sepsis is an important cause of perioperative death following PCNL.[38,39] The key mechanism is intrarenal pelvic pressure (IRP) exceeding 30 mmHg, driving pyelovenous backflow of potentially infected irrigant into the systemic circulation.[40] The IRP during PCNL is influenced by irrigation inflow and outflow, tract and sheath caliber, instrument occupancy, pelvicalyceal anatomy, patient positioning, operative duration, and the use of suction-assisted technologies.

Supine PCNL with its passive gravitational drainage maintains lower IRP throughout the procedure compared with the prone position sheath, which requires active suction to evacuate fluid.[41,42,43] Farkouh et al. demonstrated significantly higher baseline IRP in the prone position (9.1 vs. 2.7 mmHg; P < 0.001), with mean pressures of 3.2 mmHg in supine nephroscopy compared with 14.0 mmHg in prone PCNL, representing an approximately 77% reduction and a 4.4-fold lower pressure profile in the supine position (P < 0.001).[41]

Complication profiles: A domain-by-domain analysis

Hemorrhage

Clinically significant bleeding requiring transfusion occurs in approximately 3.8% of PCNL procedures, whereas angiographic embolization is required in 0.4%–1.4%.[44] Multiple meta-analyses have shown no significant difference between supine and prone PCNL regarding transfusion rates or hemoglobin drop.[45,46,47] In a large GMSV supine PCNL series, Curry et al. reported a transfusion rate of only 1.7%.[48] Overall, bleeding risk appears to depend more on tract size, number of accesses, vascular anatomy, and surgeon experience than patient position.

Colonic injury

Colonic injury during PCNL is an uncommon but potentially serious complication (<0.5%). Computed tomography-based anatomical studies by Hopper et al. demonstrated a retrorenal colon in 2% of supine versus 10% of prone patients. This indicates, theoretically, a fivefold lower risk with the supine position.[49] Hur et al. (2021) confirmed that retrorenal and posterolateral colonic positions are more frequent in prone PCNL, with the retrorenal position more common at the lower pole and the posterolateral position more frequent at the upper pole of the left kidney.[50] This anatomical advantage may reduce the risk of colonic injury during left-sided supine PCNL.

Thoracic complications

Supine PCNL preferentially uses infracostal access, avoiding the 10-15% risk of pleural complication seen in the prone supracostal upper-pole entry above the 11^th rib.[51] In a large meta-analysis, reported thoracic complication rates were numerically lower with supine PCNL (0.64%) than with prone PCNL (1.32%), although this difference was not statistically significant (P = 0.0898);[52] caution remains essential during upper-pole access.

Fluid absorption and electrolyte effects

Khoshrang et al. demonstrated significantly lower irrigation fluid absorption during complete supine PCNL compared with prone PCNL (159.4 ± 73.8 mL vs. 355 ± 121.3 mL; P = 0.0001), representing an approximately 55% reduction. However, serum sodium, potassium, BUN, and creatinine levels were comparable between the groups, with no clinically significant electrolyte disturbances.[19] Gravity-assisted drainage in the supine position likely contributes to this advantage, particularly during prolonged procedures for large stone burdens.[42]

Operative efficacy: Stone-free rate, operative time, and hospital course

Stone-free rate

The SFR is the most important indicator for success in PCNL. Earlier studies reported higher SFRs with prone PCNL, attributed to a larger posterior surface area for puncture, easier upper-pole access, and reduced renal mobility facilitating intrarenal manipulation.

However, as experience in supine PCNL increased, many studies found SFR in both positions to be comparable. The implementation of the flank-free position gave better exposure, a more optimal operative field, and easier access from the lower pole to the upper pole. Faster evacuation of the fragments in the supine position and, if need be, use of associated ECIRS helped in achieving comparable, if not better, SFRs (ranging from 75% to 95% for supine vs. 78%–94% for prone across comparative studies) in the supine position as compared to the prone position.[45,53,54,55,56,57,58]

Operative time

Reduced operative time is the most consistently reported advantage of supine PCNL. Across meta-analyses and large RCTs, the advantage ranges from 13 to 25 min (weighted mean difference approximately −18 min; 95% confidence interval −23 to −13 min across pooled analyses) per case.[58,59] The primary driver is elimination of patient repositioning between the retrograde catheterization and percutaneous access.

Hospital stay and postoperative pain

Postoperative pain and length of hospital stay appear largely comparable between supine and prone PCNL in adult patients. Although some studies have reported modest advantages for one position, most comparative studies and meta-analyses have not demonstrated clinically significant differences in these outcomes.[45,53,60,61]

Endoscopic combined intrarenal surgery

ECIRS, the simultaneous combination of antegrade percutaneous nephroscopy and retrograde flexible ureteroscopy (fURS), represents the most important technical advance enabled by supine positioning.[62,63] Performed in the GMSV position, ECIRS allows two endourologists to approach the renal collecting system simultaneously from two routes: the percutaneous tract (antegrade) and the urethra (retrograde). Calyces inaccessible to the rigid or semi-rigid nephroscope can be cleared retrogradely under direct vision. The advantage is a reduction of additional percutaneous tracts to achieve stone-free status, and reducing the operative time and complications.

ECIRS outcomes data are compelling. A large single-center study of 592 patients undergoing PCNL in the GMSV position found an overall stone clearance rate of 79%, with ECIRS performed in 27.7% of complex cases.[64] Scoffone et al. reported SFR exceeding 80% for complex and staghorn calculi managed with ECIRS in the GMSV position, appearing superior to historical prone PCNL series for comparable stone burdens.[62] A 2023 review of 200 consecutive ECIRS cases confirmed that mini ECIRS achieved equivalent clearance with lower blood loss compared with standard ECIRS.[65]

There are case reports of prone ECIRS, but based on the available data, it would be safe to conclude that prone ECIRS is ergonomically very challenging and can be performed in the prone split-leg prone position.[66] Simultaneous fURS is far easier in the supine position as compared to the prone position, and thus ECIRS distinctly holds a superior advantage in supine as compared to the prone PCNL.

Special clinical populations

Obese patients (body mass index ≥30 kg/m²)

In morbidly obese patients, prone positioning risks restrictive ventilation, vena cava compression, and pressure injuries. Supine PCNL avoids these by allowing anterolateral pannus displacement, with superior ventilatory mechanics and hemodynamic stability.[67] UG access further mitigates BMI-related radiation dose amplification (P < 0.001).[35]

Pediatric patients

In the pediatric population, supine PCNL offers comparable stone clearance to prone, with the added benefits of shorter operative time, reduced fluid absorption and hypothermia, simpler anesthetic monitoring, and lower infectious complication rates.[30,68,69]

An updated meta-analysis by Fang et al. confirmed the superiority of supine PCNL in children with regards to operative time, hospital stay, complication rates, and radiation exposure, with equivalent SFRs.[70]

Elderly patients (≥70 years)

Modified supine PCNL in patients ≥70 years achieved a 66.7% SFR, with mostly minor complications of 17.4%, and no procedure-related mortality. Reduced patient handling, particularly beneficial in elderly patients with fragile skin, osteoporosis, and higher anesthetic vulnerability, was highlighted as a major advantage of the supine approach.[71]

Cardiovascular high-risk patients

Lower fluid absorption, better anesthetic monitoring, preserved hemodynamic stability, and anesthetic technique flexibility make supine PCNL the preferred modality for patients with congestive cardiac failure, pulmonary hypertension, or significant coronary artery disease.[19,71]

Patients with musculoskeletal deformities

Patients unable to be made prone, such as in ankylosing spondylitis, severe kyphoscoliosis, spinal instrumentation, or severe thoracic deformity precluding safe prone positioning. Sabnis et al. identify musculoskeletal contraindication to prone as an absolute indication for supine PCNL.[43] In this context, supine PCNL is not a choice between equivalents but may represent the only feasible approach.

Horseshoe kidney

Horseshoe kidney creates a uniquely challenging puncture geometry: the fused isthmus rotates the lower poles medially, displacing the pelvis anteriorly and altering calyceal anatomy relative to the flank access point. In view of the medially rotated, vertically oriented upper pole calyces and medially displaced pelvis, prone PCNL is often preferred for horseshoe kidney as it provides more direct and predictable posterior calyceal access. Mazzucchi et al. [72] compared supine and prone PCNL in patients with horseshoe kidneys and found comparable SFRs, safety profiles, and complication rates, supporting supine PCNL as an effective alternative to the traditional prone approach.

Complex renal stones

For complex and staghorn calculi where ECIRS is planned, supine GMSV positioning is advantageous.[73] For complex stones without ECIRS, Choudhury et al. prospectively demonstrated that supine PCNL in the Calcutta position achieved operative times of 104.7 ± 34.5 versus 124.3 ± 22.7 min for prone (P = 0.01), with equivalent SFR and complications, in 106 consecutive patients with complex disease and difficult anatomy.[73]

Radiation exposure

Supine PCNL consistently demonstrates lower radiation exposure than prone. St-Laurent et al. found that the effective dose to the lens was 1.5 × higher for prone PCNL, and extremity dose was 1.3 × higher;[74] these differences compound across a surgical career. Supine positioning was independently associated with lower effective exposure (2.92 vs. 5.3 mSv; P = 0.0014), even when ultrasound supplemented rather than replaced fluoroscopy.[35] The combination of supine positioning and UG access represents the lowest-radiation PCNL approach currently available, confirmed across 21 RCTs (2969 patients) by Du et al.[33]

Ergonomics

Supine PCNL offers improved fluoroscopy ergonomics for the primary surgeon, though reduced nephroscope mobility within the collecting system is a recognized limitation. The more horizontal tract geometry, partially mitigated by GMSV table height modification and flank elevation, remains a technical consideration.[32,43]

DISCUSSION

Should Supine be the new default approach?

The evidence synthesis in this review leads to a clear analytical conclusion: in the hands of an experienced team, supine PCNL is noninferior to prone PCNL in every measure of efficacy, while demonstrating real and reproducible advantages in operative time,[59,60] anesthesia safety,[17] learning curve,[22,23] infection risk,[40,42] radiation exposure,[35,74] compatibility with UG,[34,35] and unique enabling of ECIRS[62,64,65] for complex disease.

No single advantage alone would be sufficient to change practice. But the convergence of a faster learning curve, shorter operative time, lower colonic injury risk,[45] lower fluid absorption,[19] equal or superior outcomes in obese,[35,67] pediatric,[70] elderly,[71] and high-risk patients,[73] and compatibility with ECIRS[64] these arguments are cumulative, independent, and mutually reinforcing.

Where does prone retain advantage?

Prone positioning retains clear advantages in selected situations: direct upper-pole posterior calyceal access in complex anatomy,[43] greater tract angulation flexibility for staghorn requiring multiple posterior tracts, and wider nephroscope manoeuvrability.[32] Surgeons experienced solely in prone PCNL also face an additional transition learning curve when adopting the supine approach.

The technology trajectory

Emerging technologies align naturally with supine PCNL: UG benefits from improved supine acoustic windows,[34] ECIRS is architecturally dependent on the GMSV position,[64] and vacuum suction systems complement the gravity-assisted drainage advantage of supine positioning.[31]

Intrarenal pressure management (IRP ≤30 mmHg) is more naturally maintained in supine positioning.[40] Miniaturized variants (mini-, ultra-mini-, micro-PCNL) and emerging robotic-assisted platforms show preferential compatibility with supine or flank access.[29,30,64]

Implications for training and guidelines

Current EAU and AUA guidelines consider supine and prone PCNL as equivalent approaches.[1,3] However, the accumulating evidence increasingly supports the supine approach across multiple clinical domains. Based on the available literature, future guideline updates may consider recommending: (i) supine PCNL (GMSV or equivalent) as the preferred primary approach in appropriately trained centers; (ii) supine PCNL as the preferred training platform for novice surgeons; (iii) prone PCNL as a complementary option for anatomically complex cases requiring direct posterior access; and (iv) UG supine PCNL as a potentially lower-risk technique in centers with relevant expertise.[33,35]

Limitations of the evidence base

This review must acknowledge limitations in the underlying evidence: (i) heterogeneity in supine position variants across studies makes strict pooling inappropriate and formal heterogeneity analysis was not performed in this narrative review; (ii) most studies do not equivalently certify supine versus prone experience, creating systematic bias against supine in comparative studies; (iii) few studies provide health-economic analyses comparing the cost implications of shorter operative time, lower complication rates, and faster learning curves; (iv) long-term outcomes (recurrence, renal function preservation) by position have not been rigorously compared in the literature; and (v) Differences in postoperative imaging modalities (X-ray vs. NCCT KUB) may affect the comparability of reported SFRs across studies.

Based on the available evidence, a pragmatic clinical position-selection approach for PCNL is proposed in Box 1, and a comparison of supine and prone PCNL is presented in Table 1.

Box 1.

Clinical position selection algorithm for percutaneous nephrolithotomy

Clinical scenario	Preferred position	Rationale
High-risk patients (ASA ≥3, obesity, difficult airway, cardiopulmonary disease, frail elderly)	Supine/modified supine PCNL	Easier airway access, improved anesthetic safety, and reduced cardiopulmonary compromise
Complex stones (staghorn calculi, multiple tracts, bilateral PCNL, complex renal anatomy)	Prone PCNL	Larger posterior surface area, multiple access options, and shorter tract length
ECIRS or combined antegrade-retrograde procedures planned	Supine/GMSV PCNL	Allows simultaneous retrograde and antegrade access with improved operating room efficiency
Standard-risk patients in high-volume prone centers	Prone PCNL remains appropriate	Excellent outcomes in experienced hands
Ultrasound-guided or suction-assisted mini-PCNL	Supine PCNL preferred	Better drainage, lower intrarenal pressure, and ergonomic advantages

Clinical note: Final position selection should be individualized according to patient comorbidity, stone complexity, surgeon expertise, and institutional workflow. ASA=American Society of Anesthesiologists, PCNL=Percutaneous nephrolithotomy, ECIRS=Endoscopic combined intrarenal surgery, GMSV=Galdakao-modified supine Valdivia

Table 1.

Comparative overview of supine versus prone percutaneous nephrolithotomy across major clinical domains(✓) advantage; (≈) equivalent

Domain	Supine PCNL	Prone PCNL
Airway and emergency access[17]	✓Unrestricted airway access; immediate CPR feasible	Restricted airway access; repositioning required
Neurological/musculoskeletal risk[18]	✓Lower risk of nerve and pressure injuries	Higher risk of brachial, ulnar, femoral, and cervical injuries
Respiratory and hemodynamic profile[19,20]	✓Better oxygenation, ventilation, and cardiovascular stability	Reduced respiratory compliance, especially in obese patients
Regional anesthesia feasibility[21]	✓Entire procedure feasible without repositioning	Often requires conversion to general anesthesia
Learning curve[22,23,24]	✓Faster proficiency acquisition	Longer learning curve
Lower/mid-pole access	✓Excellent access	✓Excellent access
Upper-pole access[21]	Feasible in experienced hands	✓More intuitive and widely practised
Retrorenal colon risk[49,74]	✓Lower (~2%)	Higher (~10%)
Thoracic complications[50,51]	✓Lower due to predominantly infracostal access	Higher with supracostal puncture
Fluid absorption and IRP[19,40,41,42,70]	✓Lower due to gravity-assisted drainage	Higher; often requires active suction
Hemorrhage/transfusion[44,45,46,47,48]	≈Comparable	≈Comparable
Stone-free rate[45,53]	≈Comparable in experienced hands	≈Comparable
Operative time[58,59]	✓Shorter by approximately 13–25 min	Longer, partly due to repositioning
Hospital stay[52,60]	≈Comparable	≈Comparable
ECIRS compatibility[61,62,63,64,65]	✓Ideal platform for ECIRS	Technically more challenging
Ultrasound-guided access[34,35,36]	✓Better acoustic windows and ergonomics	More posterior acoustic interference
Radiation exposure[33,73]	✓Lower exposure to surgeon and patient	Higher fluoroscopic scatter exposure
Mini-/ultra-mini PCNL[29,30]	✓Better ergonomics and shorter operative time	Effective but technically more demanding
Obese and high-risk patients[19,35,66,70]	✓Better ventilation, ergonomics, and anesthetic safety	Technically and anesthetically challenging
Pediatric and elderly patients[29,67,68,69,70]	✓Better tolerance and lower complication profile	Comparable efficacy but higher positioning-related concerns
Musculoskeletal disorders[43]	✓Preferred/feasible option	Often contraindicated
Horseshoe kidney and anomalous anatomy[71]	✓Safe and feasible	Technically challenging
Nephroscope manoeuvrability[32]	Reduced horizontal tract mobility	✓Wider range of motion
Surgeon ergonomics[32,43]	✓Improved comfort and reduced radiation scatter	Standard ergonomics
Suction/vacuum-assisted systems[31,32,33]	✓Synergistic with gravity drainage	Compatible but less efficient
Zero-intrarenal-pressure strategies[75]	✓Naturally aligned with technique	Requires active pressure control

CPR=Cardiopulmonary resuscitation, ECIRS=Endoscopic combined intrarenal surgery, IRP=Intrarenal pressure, PCNL=Percutaneous nephrolithotom

CONCLUSIONS

This narrative and analytical review summarizes more than five decades of PCNL evolution and the current evidence comparing supine and prone approaches. Supine PCNL, particularly the GMSV position, achieves stone-free outcomes comparable to prone PCNL while offering advantages such as shorter operative time, faster learning curve, lower colonic injury risk, reduced fluid absorption, improved anesthetic and hemodynamic safety, lower radiation exposure, and better suitability for high-risk patients. Supine positioning also uniquely enables ECIRS, which is highly effective for complex and staghorn calculi.

Prone PCNL continues to retain advantages in upper-pole access and wider nephroscope manoeuvrability. However, emerging technologies including UG access, miniaturized PCNL, suction-assisted systems, and low intrarenal pressure strategies appear increasingly aligned with the supine approach.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.