An interventional study of Microsurgical Decompression with Extension of Fusion and Microsurgical Decompression Alone in Adjacent Segment Disease and Lumbar Spinal Stenosis, sponsored by Charite University, Berlin, Germany. Recruiting at 1 site in Germany. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-28.
Sponsored by Charite University, Berlin, Germany · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to learn whether microdecompression alone is as effective as decompression with extension of fusion surgery in patients with symptomatic adjacent segment stenosis after previous lumbar fusion surgery.
The main questions it aims to answer are:
Is microdecompression alone non-inferior to decompression with extension of fusion in improving disability 24 months after surgery, as measured by the Oswestry Disability Index (ODI)? Does microdecompression alone result in similar or lower rates of complications, reoperations, pain, and radiological progression compared with decompression and fusion?
Researchers will compare microdecompression alone to decompression with extension of lumbar fusion to determine whether the less invasive procedure can achieve similar clinical outcomes while reducing surgical burden and preserving spinal structures.
Participants will:
Be randomly assigned to one of two treatment groups: microdecompression alone or decompression with extension of lumbar fusion.
Undergo the assigned surgical treatment. Attend clinical and radiological follow-up visits at 6, 12, and 24 months after surgery.
Complete questionnaires assessing disability, pain, quality of life, sleep quality, and mental health.
Undergo routine imaging and clinical examinations to evaluate treatment outcomes and possible complications.
458 studies on the registry are indexed under Spinal Stenosis; 105 are open to participants now.
This study's planned enrollment of 338 is above the median of 80 across 281 interventional studies indexed under Spinal Stenosis.
Browse Spinal Stenosis studies →Charite University, Berlin, Germany is the lead sponsor of 857 studies on the registry; 129 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Decompression and fusion
Procedure: Microsurgical Decompression with Extension of Fusion
Mircosurgical decompression only
Procedure: Microsurgical Decompression Alone
Participants undergo microsurgical decompression of symptomatic adjacent segment stenosis combined with extension of the existing lumbar fusion.
Participants undergo microsurgical decompression of symptomatic adjacent segment stenosis after previous lumbar fusion surgery without extension of the existing fusion.
Proportion of Participants Achieving at Least 30% Reduction in Oswestry Disability Index (ODI)
The primary endpoint is the proportion of participants achieving a reduction of at least 30% in the Oswestry Disability Index (ODI) compared with baseline. The ODI is a validated patient-reported outcome measure assessing disability related to lumbar spine disorders on a scale from 0% to 100%. A reduction of at least 30% is considered clinically meaningful.
Time frame: 24 months after surgery
Pain related disability
Disability related to low back pain assessed using the Oswestry Disability Index (ODI). The ODI score ranges from 0 to 100%, with higher scores indicating greater disability and worse functional impairment.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Leg Pain Intensity at Rest
Pain intensity assessed using the Numeric Rating Scale (NRS; 0-10) for leg pain at rest.The NRS ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Leg Pain Intensity during Movement
Pain intensity assessed using the Numeric Rating Scale (NRS; 0-10) for leg pain during movement.The NRS ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Back Pain Intensity at Rest
Pain intensity assessed using the Numeric Rating Scale (NRS; 0-10) for back pain at rest.The NRS ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Back Pain Intensity during Movement
Pain intensity assessed using the Numeric Rating Scale (NRS; 0-10) for back pain during movement.The NRS ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Maximum Walking Distance
Maximum walking distance measured in meters.
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Health-Related Quality of Life Assessed by the 36-Item Short Form Health Survey (SF-36)
generates eight domain scores (physical functioning, role limitations due to physical health, bodily pain, general health perceptions, vitality, social functioning, role limitations due to emotional problems, and mental health), each transformed to a scale ranging from 0 to 100, with higher scores indicating better health-related quality of life and functional status. Unit of Measure: Points on a scale (0-100).
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Health-Related Quality of Life Assessed by the EuroQol 5-Dimension 5-Level Questionnaire (EQ-5D-5L) Index Score
Health-related quality of life assessed using the EuroQol 5-Dimension 5-Level questionnaire (EQ-5D-5L). The EQ-5D-5L evaluates five dimensions of health status (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), each with five response levels. Responses are converted into a single EQ-5D-5L Index Score using an established country-specific value set. Higher index scores indicate better health-related quality of life. Unit of Measure: Utility index score (higher scores indicate better health-related quality of life).
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Mood Assessed by the German General Depression Scale - Short Form (ADS-K)
Depressive symptoms assessed using the German General Depression Scale - Short Form (ADS-K). The ADS-K is a self-report questionnaire comprising 15 items, each rated on a 4-point Likert scale (0-3 points). Total scores range from 0 to 45 points, with higher scores indicating more severe depressive symptomatology and worse mood status. Unit of Measure: Points on a scale (range: 0-45; higher scores indicate more severe depressive symptoms)
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Sleep Quality Assessed by the Pittsburgh Sleep Quality Index (PSQI)
Sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI). The PSQI is a self-administered questionnaire evaluating sleep quality and disturbances over the previous month across seven domains: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction. Component scores are summed to generate a global PSQI score ranging from 0 to 21 points, with higher scores indicating poorer sleep quality and greater sleep disturbance. Unit of Measure: Points on a scale (range: 0-21; higher scores indicate worse sleep quality).
Time frame: Baseline (before surgery), 6 months after surgery, 12 months after surgery, and 24 months after surgery.
Length of hospital stay
Length of hospital stay measured in days from surgery until hospital discharge.
Time frame: From date of surgery until hospital discharge, up to 30 days postoperatively
Intensive Care Unit Stay
Duration of intensive care unit stay measured in days.
Time frame: From admission to the intensive care unit after surgery until discharge from the intensive care unit, up to 30 days postoperatively.
Additional or Revision Spine Surgery
Proportion of participants requiring additional spinal surgery or revision surgery during follow-up.
Time frame: Up to 24 months after surgery
Perioperative Complications
Number and type of perioperative complications associated with the surgical procedure.
Time frame: Perioperative/Periprocedural
Operative Parameters
Operative duration, intraoperative blood loss
Time frame: Perioperative/Periprocedural
Dynamic Spondylolisthesis
Presence of dynamic spondylolisthesis defined as a translation of ≥3 mm on flexion-extension radiographs.Unit of Measure: Participants with dynamic spondylolisthesis.
Time frame: 24 month after surgery
Central Stenosis Severity Assessed by the Schizas Classification
Central canal stenosis at the adjacent segment assessed on MRI using the Schizas classification (Grades A-D).Unit of Measure: Grade (A-D; higher grades indicate more severe stenosis).
Time frame: 24 months after surgery
Foraminal Stenosis Severity Assessed by the Lee Classification
Foraminal stenosis at the adjacent segment assessed on MRI using the Lee classification (Grades 1-4).Unit of Measure: Grade (1-4; higher grades indicate more severe foraminal stenosis).
Time frame: 24 months after surgery.
Implant Integrity
Implant integrity assessed on radiographs, including evidence of implant loosening, breakage, or material dislocation.Unit of Measure: Participants with implant failure.
Time frame: 24 months after surgery.
Segmental Lordosis
Segmental lordosis measured on standing lateral radiographs.Unit of Measure: Degrees (°).
Time frame: 24 months after surgery.
Plan to share: Yes — Individual participant data underlying the results reported in publications arising from this study, after de-identification, will be made available upon reasonable request to the corresponding investigator. Supporting documents including the study protocol, statistical analysis plan, and data dictionary will also be made available.
Supporting information: Study protocol, Statistical analysis plan, Analytic code
Time frame: Beginning 12 months following publication of the primary study results and ending 5 years after publication.
Access criteria: De-identified individual participant data (IPD) underlying the results reported in publications arising from this study, as well as the study protocol, statistical analysis plan, and analytic code, will be made available to qualified researchers. Access will be granted to investigators who provide a scientifically sound research proposal that is approved by the study steering committee. Requests must be submitted to the study sponsor and should specify the intended use of the data. Data will be shared only after publication of the primary study results and following execution of an appropriate data-sharing agreement. Access will be provided through a secure electronic data transfer system in accordance with applicable data protection regulations.
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Charite University, Berlin, Germany →