Lower Back Muscle Size and Recovery After Lumbar Disc Herniation Surgery

August 13, 2026 updated by: Doğa Meriç Yükselen, Fatih Sultan Mehmet Training and Research Hospital

Association of Preoperative Psoas Muscle Index and Multifidus Muscle Area With Postoperative Quality of Recovery Assessed Using the Quality of Recovery-15 (QoR-15) in Patients Undergoing Surgery for Lumbar Disc Herniation: A Prospective Observational Study

Recovery after surgery for a herniated disc in the lower back differs from person to person. The size of the muscles around the lower spine may be related to recovery, but this relationship is not well understood.

The purpose of this observational study is to determine whether the size of two lower-back muscles, the psoas and multifidus muscles, measured on magnetic resonance imaging (MRI) scans obtained before surgery is related to recovery after surgery. The study will include 100 adults aged 18 to 75 years who are scheduled for elective surgery for lumbar disc herniation.

Participants will receive their usual anesthesia, surgery, and postoperative care. The study will not require any additional imaging, blood tests, medicines, or procedures. Researchers will use each participant's existing preoperative lumbar MRI scan to measure the psoas and multifidus muscles. Participants will complete the 15-item Quality of Recovery questionnaire (QoR-15) before surgery and again 24 hours, 48 hours, and 7 days after surgery. Researchers will also collect information routinely recorded during care, including pain scores, pain medicine use, nausea and vomiting, time spent in the recovery unit, time to first walking, and length of hospital stay.

The primary objective is to determine whether preoperative psoas muscle index and multifidus muscle cross-sectional area are independently associated with postoperative Quality of Recovery-15 (QoR-15) scores 24 hours after lumbar disc herniation surgery.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a single-center, prospective observational cohort study involving 100 adults undergoing elective surgery for lumbar disc herniation. No treatment, exposure, or anesthetic technique will be assigned by the study protocol. All participants will receive standard general anesthesia, surgery, and postoperative care according to routine clinical practice and the decisions of the responsible clinical teams. No additional imaging, laboratory testing, medication, or invasive procedure will be performed for research purposes.

Existing preoperative lumbar magnetic resonance imaging scans obtained as part of routine clinical care will be evaluated. Muscle measurements will be performed on axial T2-weighted images at the level of the inferior endplate of the L3 vertebra. The right and left psoas muscles will be manually outlined, and their cross-sectional areas will be summed to calculate the total psoas area. The total psoas area will be divided by height squared to calculate the psoas muscle index in cm²/m².

The right and left multifidus muscles will be evaluated on the same MRI section. Their cross-sectional areas will be measured and summed to calculate the total multifidus muscle area. A height-adjusted multifidus muscle index will also be calculated. MRI measurements will be performed by an investigator who is unaware of the participants' clinical outcomes and QoR-15 scores.

Quality of recovery will be assessed using the validated Turkish version of the 15-item Quality of Recovery questionnaire. The QoR-15 evaluates physical comfort, emotional state, physical independence, psychological support, and pain. Total scores range from 0 to 150, with higher scores indicating better recovery. The questionnaire will be administered before surgery and at 24 hours, 48 hours, and 7 days after surgery.

Postoperative pain at rest will be assessed using the Numeric Rating Scale at 2, 6, 12, and 24 hours after surgery. Other routinely collected data will include opioid and other analgesic consumption during the first 24 hours, requirement for rescue analgesia, postoperative nausea and vomiting, antiemetic requirement, length of stay in the post-anesthesia care unit, time to first mobilization, and total length of hospital stay.

The primary analysis will evaluate the associations of the preoperative psoas muscle index and multifidus muscle measurements with the QoR-15 score 24 hours after surgery. Secondary analyses will evaluate their associations with QoR-15 scores at 48 hours and 7 days, postoperative pain scores, analgesic consumption, postoperative nausea and vomiting, recovery unit stay, time to first mobilization, and hospital length of stay.

Correlations will be assessed using Pearson or Spearman correlation analysis, as appropriate. Multivariable linear regression analysis will be used to identify whether the preoperative muscle measurements are independently associated with the 24-hour QoR-15 score after adjustment for relevant demographic and clinical variables.

Study Type

Observational

Enrollment (Estimated)

100

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Turkey (Türkiye)
      • Istanbul, Turkey (Türkiye), 34752
        • Fatih Sultan Mehmet Training and Research Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

The study population will consist of a consecutive sample of adult patients aged 18 to 75 years with ASA physical status I-III who are scheduled for elective surgery for lumbar disc herniation under general anesthesia at Fatih Sultan Mehmet Training and Research Hospital. Eligible participants must have an existing preoperative lumbar MRI suitable for psoas and multifidus muscle measurements and must be able to complete the Turkish version of the QoR-15 questionnaire.

Description

Inclusion Criteria:

  • Age between 18 and 75 years
  • Scheduled for elective surgery for lumbar disc herniation
  • American Society of Anesthesiologists physical status I-III
  • Availability of a preoperative lumbar MRI obtained as part of routine clinical care
  • Scheduled to undergo surgery under general anesthesia
  • Sufficient cognitive and communication ability to understand and complete the quality of recovery (QoR-15) questionnaire
  • Willingness to participate and provision of written informed consent

Exclusion Criteria:

  • Emergency surgery
  • Revision lumbar spine surgery
  • Surgery for a spinal tumor, infection, trauma, vertebral fracture, spinal deformity, advanced spinal stenosis, or another condition other than lumbar disc herniation
  • Planned spinal fusion or instrumentation
  • History of a neuromuscular disorder
  • Severe cognitive impairment, inability to communicate, or inability to complete the QoR-15 questionnaire
  • Chronic opioid use or a history of opioid dependence
  • Preoperative lumbar MRI images of insufficient quality for psoas or multifidus muscle measurement

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Elective Lumbar Disc Herniation Surgery Cohort
Adults aged 18 to 75 years with ASA physical status I-III who are scheduled for elective surgery for lumbar disc herniation under general anesthesia. Participants will receive routine perioperative care, and no intervention will be assigned by the study protocol. The exposures of interest are the preoperative psoas muscle index and multifidus muscle area and index measured using existing lumbar Magnetic Resonance Imaging (MRI) scans. QoR-15 scores will be recorded before surgery and at 24 hours, 48 hours, and 7 days after surgery. Postoperative pain, analgesic consumption, nausea and vomiting, recovery unit stay, time to first mobilization, and hospital stay will also be recorded.
Other: Preoperative Psoas and Multifidus Muscle Measurements
Preoperative psoas muscle index and multifidus muscle cross-sectional area and index will be measured by manual segmentation of existing axial T2-weighted lumbar MRI images at the L3 inferior endplate level. No additional MRI examination or clinical intervention will be performed. These measurements represent observational exposures whose associations with postoperative QoR-15 scores and other recovery outcomes will be evaluated

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Quality of Recovery-15 (QoR-15) Total Score
Time Frame: Muscle measurements: preoperative; QoR-15 assessment: 24 hours after surgery
The association between preoperative psoas muscle index and multifidus muscle measurements and the total Quality of Recovery-15 (QoR-15) score 24 hours after surgery will be evaluated using correlation and multivariable linear regression analyses.
Muscle measurements: preoperative; QoR-15 assessment: 24 hours after surgery

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
QoR-15 Scores at 48 Hours and 7 Days After Surgery
Time Frame: 48 hours and 7 days after surgery
Quality of recovery will be assessed using the total Quality of Recovery-15 (QoR-15) score. The questionnaire contains 15 items and has a total score ranging from 0 to 150, with higher scores indicating better postoperative recovery.
48 hours and 7 days after surgery
Postoperative Numeric Rating Scale Pain Scores at Rest
Time Frame: 2, 6, 12, and 24 hours after surgery
Pain intensity at rest will be assessed using the Numeric Rating Scale. Scores range from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain.
2, 6, 12, and 24 hours after surgery
Total Opioid Consumption During the First 24 Hours
Time Frame: Within the first 24 hours after surgery
The cumulative dose of opioid analgesics administered during the first 24 hours after surgery will be obtained from medication records. If more than one opioid is administered, doses will be converted to intravenous morphine milligram equivalents for analysis. Higher values indicate greater opioid consumption.
Within the first 24 hours after surgery
Requirement for Rescue Analgesia
Time Frame: Within the first 24 hours after surgery
The number and percentage of participants who require any additional rescue analgesic medication because of inadequate pain control will be recorded.
Within the first 24 hours after surgery
Incidence of Postoperative Nausea and Vomiting
Time Frame: Within the first 24 hours after surgery
The number and percentage of participants experiencing at least one episode of nausea, vomiting, or both will be recorded using patient reports and routine clinical records.
Within the first 24 hours after surgery
Length of Stay in the Post-Anesthesia Care Unit
Time Frame: From post-anesthesia care unit admission to discharge, typically within 2 hours after surgery
Time from admission to discharge from the post-anesthesia care unit will be recorded in minutes.
From post-anesthesia care unit admission to discharge, typically within 2 hours after surgery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Fatih Sultan Mehmet Training and Research Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 1, 2026

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

July 18, 2026

First Submitted That Met QC Criteria

August 13, 2026

First Posted (Actual)

August 17, 2026

Study Record Updates

Last Update Posted (Actual)

August 17, 2026

Last Update Submitted That Met QC Criteria

August 13, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • FSMTRHPSOAS
  • 2026/06-37 (Other Identifier: University of Health Sciences Fatih Sultan Mehmet Training and Research Hospital Scientific Research Ethics Committee)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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