An interventional study of Blood-Flow-Restriction Training and Sham-BFR in Muscle Atrophy, Postoperative Pain and Spondylolisthesis, sponsored by University Hospital, Bonn. Completed at 1 site in Germany. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-10-16.
Sponsored by University Hospital, Bonn · Not applicable, Interventional, and Treatment
This project investigates the effects of the Blood-Flow-Restriction (BFR) training method on postoperative muscle atrophy and pain after spinal surgery. Two groups are formed for this purpose. The intervention group receives a everyday BFR training during the postoperative stay at an individually measured occlusion pressure of 60-80%. The control group performs sham-BFR training at a fixed occlusion pressure of 20mmHg. The examinations are carried out before and several times after the operation (longest follow-up: 6 months). Among other things, muscle mass, muscle strength, pain perception and quality of life are assessed using questionnaires.
Methodology and implementation Type of study
Prospective, interventional study in the context of clinical orthopedic routine (Non-AMG, Non-MPG):
This scientific project investigates the influence of blood-flow restriction training as a therapeutic intervention after spinal surgery for postoperative muscle preservation.
Study design Parallel study design The aim of this study is to investigate the influence of postoperative blood-flow restriction (BFR) application on muscle preservation and muscular-functional rehabilitation after spinal surgery. Postoperative muscle mass and strength loss is related not only to the size of the surgical procedure, but also to the prolonged rehabilitation after spine surgery. Since our patients are not able to perform large mechanical loads for a longer period of time (usually six weeks), we use the BFR training method as a training intervention.
The thesis of this work focuses the postoperative use of BFR training to reduce muscle atrophy during hospitalisation phase, and the supporting effects of BFR-Training on functional rehabilitation. For this purpose, a partially blinded randomised controlled trial will treat one group with BFR and one group with Sham-BFR and compare the results.
Classification of patients and study procedure Subjects who fulfil the above-mentioned inclusion criteria for study participation will be informed orally and by means of an information sheet about the planned study by the investigator and given written information.
Prior to the start of the study, the written consent of the subjects to participate in the study will be obtained. The study takes into account the ethical principles of the Declaration of Helsinki in its current version (2013).
Randomisation of patients The patients will be divided into two groups of 25 patients each. Randomisation will be done by classical analogue double lottery.
Description of the interventions Intervention: Blood-Flow Restriction Training (BFR). BFR training involves the application of tourniquets during a passive or active movement intervention to provide an additive metabolic stimulus. The tourniquets are applied as far as possible proximally to the thigh and a pressure is applied during the movement that suppresses only part of the venous return of an extremity (=venous pooling). Venous occlusion is induced by a cuff system routinely used in strength training (Delfi Medical Innovations Inc., Vancouver, Canada). The pressure applied is calculated on the basis of the individual occlusion pressure via duplex sonography at the start of each training session. The test person lies at rest while the cuff is inflated until no more blood flow can be detected in the extremity (= occlusion pressure). Of this occlusion pressure, 60-80% is subsequently used for the BFR intervention. The loading protocol provides for daily units of 60 minutes at intervals (5 minutes occlusion + 5 minutes free flow, six times in total), over a period of two to 14 days.
Control: Control group, Sham-BFR (CG). Patients in the control group (CG) perform the same exercise protocol as patients in the BFR intervention group, except that they receive the standardized low BFR pressure of 20mmHg.
Investigation/aim parameters of the study Investigations For the purpose of this project, the examinations will be divided into basal examinations and in-rehabilitation examinations.
Study population
Patient inclusion criteria:
Patient exclusion criteria:
Number of patients: 30 (two groups with 15 subjects each)
Discontinuation of the study in one patient (drop-out)
One or more of the following circumstances may lead to a patient dropping out of the study (this patient will be counted as a drop-out):
Statistical calculation of the number of cases A power analysis performed using G*Power 3.1.9. assuming a mean effect size (f) of 0.25, an alpha error of 0.05 and a test power of (1-β) of 0.85 for the analysis of variance with repeated measures resulted in an optimal sample size of N = 26 (i.e. 13 subjects per group).
Because of the long follow-up period of 6 months and the resulting increased possibility of drop-out patients, we agreed on a number of 25 subjects per group.
Recruitment measures The patients will be recruited from the patient pool of the Department of Orthopaedics and Trauma Surgery of the University Hospital Bonn.
Archiving and data protection All data generated in the course of the study are protected by data protection laws. Personal data will not be passed on or made accessible to the public by the medically responsible study director or the investigator (Alexander Franz) or any other person involved in the conduct of the study. Only pseudonymized patient data will be passed on and stored. The pseudonymization is carried out by means of an ascending numerical series by the medically responsible study director or the investigator. Only the investigators are allowed to assign the personal data to the study data. The allocation key is stored on an external hard drive and is managed by the principal investigator (Alexander Franz). After completion of the study, the allocation key is deleted and the data management is changed from pseudonymization to anonymization. The evaluation of the data will be anonymized. All data will be managed in accordance with data protection regulations.
412 studies on the registry are indexed under Muscular Atrophy; 77 are open to participants now.
This study's enrollment of 30 is below the median of 40 across 326 interventional studies indexed under Muscular Atrophy.
Browse Muscular Atrophy studies →University Hospital, Bonn is the lead sponsor of 154 studies on the registry; 28 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
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.
The first group will serve as the control group and will receive an additional daily Sham BFR intervention of 20mmHg postoperatively as part of routine clinical care.
Other: Sham-BFR
The second group will serve as the intervention group and will receive an additional daily passiveBFR intervention with 80% of the individual LOP postoperatively as part of routine clinical care.
Other: Blood-Flow-Restriction Training
For the pBFR intervention, the Personalized Tourniquet System for Blood Flow Restriction from Delfi Medical Innovations Inc. (Vancouver, Canada) were used. The cuffs were applied to both lower extremities as far proximally as possible and were connected to the control device. Before starting the training program, the individual LOP was measured of both lower limb in a restring, laying position by the control device. The Intervention-Group performed the training at 80% of their individual LOP. The training was performed alternately on both lower extremities. The time intervals were set at five minutes occlusion and five minutes rest. Each leg received five intervals of BFR-induced occlusion training, resulting in a total 50 minutes of daily training. During the entire training period, the patient was in a resting position, laying in the hospital bed.
Also known as: BFR
For the sham-BFR intervention, the Personalized Tourniquet System for Blood Flow Restriction from Delfi Medical Innovations Inc. (Vancouver, Canada) were used. The cuffs were applied to both lower extremities as far proximally as possible and were connected to the control device. Before starting the training program, the individual LOP was measured of both lower limb in a restring, laying position by the control device. The Control-Group was trained with a fixed pressure of 20 mmHg, independent of their individual LOP. The training was performed alternately on both lower extremities. The time intervals were set at five minutes occlusion and five minutes rest. Each leg received five intervals of BFR-induced occlusion training, resulting in a total 50 minutes of daily training. During the entire training period, the patient was in a resting position, laying in the hospital bed.
Muscle Mass
BIA-/ DXA-Measurement
Time frame: Pre- to 6 weeks Post Surgery
Perceived Pain
VAS 100mm
Time frame: Pre- to 6 weeks Post Surgery
Plan to share: No
No publications or documents are linked to this record.
Ran from Mar 2022 to primary completion in Nov 2024, 32 months.
Of 168 non-industry interventional studies with no phase under Muscular Atrophy, half reached primary completion within 22 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 41. This study's 32 months is above that.
Counting every sponsor, half of 174 studies reached it within 22 months; a quarter within 9 and three quarters within 37.
How these figures are worked out, and which studies are left out of them.
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 ↗
This study is completed, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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