Supine vs. Prone PCNL for Large Renal Stones: A Randomized Trial in Yemen.

Comparative Evaluation of Early Postoperative Complications, Cost-Effectiveness, and Patient-Centered Outcomes Following Supine and Prone Standard Percutaneous Nephrolithotomy (PCNL): A Randomized Controlled Trial

The goal of this clinical trial is to compare the safety, cost-effectiveness, and patient recovery of two different surgical positions for percutaneous nephrolithotomy (PCNL) in adult patients aged 18 to 70 years with kidney stones larger than 2 cm. The main questions it aims to answer are:

• Does the supine (lying on the back) surgical position result in fewer early postoperative complications than the traditional prone (lying on the stomach) position?
• Does the supine position reduce the total surgery time, direct hospital costs, and postoperative pain?

Researchers will compare patients assigned to undergo PCNL in the supine position to those assigned to the prone position to see if the supine approach offers a safer, more cost-effective, and more comfortable recovery.

Participants will:

• Undergo standard PCNL surgery to remove their kidney stones in either the supine or prone position.
• Have their pain levels, surgery time, and any early surgical complications monitored during their hospital stay.
• Complete brief questionnaires regarding their pain, overall surgical satisfaction, and quality of life at 1 month and 3 months after the procedure.

Study Overview

• Status: Not yet recruiting
• Conditions: Kidney Calculi; Nephrolithiasis
• Intervention / Treatment: Procedure: Supine Percutaneous Nephrolithotomy (PCNL); Procedure: Prone Percutaneous Nephrolithotomy (PCNL)

• Study Type: Interventional
• Enrollment (Estimated): 140
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Waleed Mohammed Al-Ata, M.B.B.Ch; Phone Number: +967777775223; Email: h.jowah@su.edu.ye

Study Locations

• Yemen
  • Sanaa, Yemen, 13078
    • Al-Kuwait University Hospital
    • Contact: Dr. Waleed Mohammed Al-Ata, M.B.B.Ch; Phone Number: +967777775223; Email: h.jowah@su.edu.ye

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients aged 18-70 years.
• Diagnosis of solitary or multiple renal stones with a cumulative diameter greater than 2 cm, confirmed by imaging (CT KUB).
• Patients eligible for standard PCNL (24-30 Fr).
• American Society of Anesthesiologists (ASA) physical status I-III.
• Willingness and ability to provide informed consent.

Exclusion Criteria:

• Patients with active urinary tract infection (UTI) not responding to antibiotics.
• Patients with bleeding diathesis or on anticoagulant therapy that cannot be safely discontinued.
• Patients with anatomical abnormalities of the kidney or urinary tract that preclude standard PCNL.
• Pregnant women.
• Patients with severe cardiopulmonary disease where general anesthesia or prolonged surgical positioning is contraindicated.
• Patients with a history of previous ipsilateral renal surgery.
• Patients unwilling or unable to comply with follow-up protocols.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Supine PCNL; Patients will undergo standard percutaneous nephrolithotomy (24-30 Fr tract size) performed in the supine position.	Procedure: Supine Percutaneous Nephrolithotomy (PCNL); Standard PCNL performed with the patient in the supine position using a standard 24-30 Fr tract.
Active Comparator: Prone PCNL; Patients will undergo standard percutaneous nephrolithotomy (24-30 Fr tract size) performed in the conventional prone position.	Procedure: Prone Percutaneous Nephrolithotomy (PCNL); Standard PCNL performed with the patient in the traditional prone position using a standard 24-30 Fr tract.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence and Severity of Early Postoperative Complications	Complications will be assessed and classified using the Modified Clavien-Dindo Classification system. The scale ranges from Grade I (minor deviation from normal postoperative course) to Grade V (death of the patient). A lower grade indicates a better clinical outcome.	Up to 30 days post-surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Operative Time	Total duration of the surgical procedure, measured continuously from the initial skin incision to the final skin closure, recorded in minutes.	Intraoperative (Day 0)
Postoperative Pain Score	Postoperative pain will be evaluated using the Visual Analog Scale (VAS). The scale ranges from 0 to 10, where 0 represents "no pain" and 10 represents the "worst imaginable pain." Lower scores indicate better pain control.	At 6 hours, 12 hours, and 24 hours post-surgery
Health-Related Quality of Life (HRQoL)	Measured using the EQ-5D-5L questionnaire, which assesses mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Scores are converted into an index value where higher scores indicate a better quality of life.	At 1 month and 3 months post-surgery
Patient Satisfaction Score	Overall patient satisfaction with the surgical experience, anesthetic process, and early recovery, measured using a 5-point Likert scale questionnaire (1 = highly dissatisfied, 5 = highly satisfied). Higher scores indicate greater patient satisfaction.	At 30 days post-surgery
Direct Hospitalization Costs	Total direct medical costs associated with the procedure, calculated as the sum of disposable medical supply costs and hospital stay duration costs. Measured in Yemeni Rials (YER).	From hospital admission to hospital discharge (typically 1 to 7 days)

Collaborators and Investigators

• Sponsor: Sana'a University

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 30, 2027

Study Registration Dates

• First Submitted: May 31, 2026
• First Submitted That Met QC Criteria: May 31, 2026
• First Posted (Actual): June 4, 2026

Study Record Updates

• Last Update Posted (Actual): June 4, 2026
• Last Update Submitted That Met QC Criteria: May 31, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Kidney Stones; PCNL; Percutaneous Nephrolithotomy; Supine PCNL; Prone PCNL
• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urolithiasis; Urinary Calculi; Pathological Conditions, Signs and Symptoms; Kidney Calculi; Nephrolithiasis
• Other Study ID Numbers: PCNL-SANA-2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No