An interventional study of Blood Flow Restriction Training and Sham Blood Flow Restriction Training in Patellar Dislocation, Knee Injuries and Leg Injury, sponsored by Caitlin Conley. Recruiting at 4 sites in United States. Open to participants aged 14 Years to 40 Years. Per ClinicalTrials.gov, last updated 2026-08-21.
Sponsored by Caitlin Conley · Not applicable, Interventional, and Treatment
This research study is designed to allow health care professionals and researchers to answer many questions about whether a new type of physical therapy called blood flow restriction training (called BFRT) will improve recovery for those with patellar instability.
Participants will randomly be assigned to 1 of 2 groups. This means that neither the participant or their doctor will not choose the treatment, but that the treatment will be randomly selected (like a coin toss). The study treatments is blood flow restriction training (BFRT). BFRT uses an air cuff that is inflated around the top of the thigh. This temporarily limits blood flow to the muscles and may allow the participant to recover strength more quickly after injury. As will be described later, the participant will be closely monitored during all study treatments to make sure they are as safe as possible.
The two groups that participants could be assigned to are:
Physical Therapy Sessions: We are comparing two physical therapy interventions, one is the standard of care and the other is the standard of care plus an additional treatment. Participants have a 50/50 chance of receiving either treatment. If randomized to receive BFRT, the air cuffs will then be placed on the participants' thighs and they will be doing a standardized exercise program that will vary depending on the stage of rehabilitation they are in and as determined by the study personnel. Participants will also complete a standardized course of physical therapy. Activities in physical therapy may include ice over the knee, range of motion exercises to maintain hip strength and gait training exercises as needed.
The following procedures may be performed. Some procedures may not be performed due to time constraints, availability of equipment, and/or by the decision of the investigator. Before initiating physical therapy, participants will be asked some questions including but not limited to the following: age, sex, level of activities, and expectations. Participants will also complete a Sports Activity Scale to determine their physical activity level.
Timeline of Study Visits:
Visit 1 Screening and enrollment: Upon arriving at the clinic or Biomotion Laboratory, potential subjects will have the following assessments: range of motion and knee instability, both of which are the standard of care for a patient with a suspected patellar instability.
After providing informed consent to participate in the study, we will ask you to provide a urine sample and will collect about 2 teaspoons of blood for laboratory testing. The blood will be collected from your arm using standard venipuncture. In addition, we will ask you questions about your medical history including current medications, demographic information, BMI, and smoking status. You will be asked to complete three study questionnaires: the Norwich Patella Instability Score which asks questions about your knee, the Cincinnati Occupational Rating Scale which asks questions about the physical demands of your job or daily life, and a Visual Analogue Scale that will ask you to rate your current pain. You will be randomized to either standard physical therapy or standard physical therapy with BFRT. You have a 50/50 chance of having BFRT. We will also schedule you to go to the BioMotion laboratory for baseline strength testing and to have your first study MRI at the MRISC.
Visit 2 (1 week)
Visit 3 (5 weeks)
Visit 4 (9 weeks)
Visit 5 (6 months)
Visit 6 (1 year)
Visit 7 (2 years)
41 studies on the registry are indexed under Patellar Dislocation; 9 are open to participants now.
This study's planned enrollment of 78 is above the median of 50 across 22 interventional studies indexed under Patellar Dislocation.
Browse Patellar Dislocation studies →This is the only study on the registry with Caitlin Conley as lead sponsor.
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.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will undergo 8 weeks of sham blood flow restriction training with cuff inflated to less than 10% occlusion.
Device: Sham Blood Flow Restriction Training
Participants will undergo 8 weeks of blood flow restriction training with cuff inflated to 60% occlusion.
Device: Blood Flow Restriction Training
Participants will undergo 8 weeks of blood flow restriction training with cuff inflated to 60% occlusion.
Participants will undergo 8 weeks of sham blood flow restriction training with cuff inflated to less than 10% occlusion.
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: Baseline
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: 5 Weeks
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: 9 Weeks
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: 6 Months
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: 12 Months
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 1 Week
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 5 Weeks
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 9 Weeks
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 6 Months
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 12 Months
MRI T1rho
Increased T1rho relaxation times have been associated with loss of proteoglycan content. This then corresponds with MRI changes associated with the loss of proteoglycan content. Patients with patellofemoral pain and maltracking have been demonstrated to have significantly greater T1rho relaxation times in the lateral facet of the patella when compared to healthy volunteers.
Time frame: 1 Week
MRI T1rho
Increased T1rho relaxation times have been associated with loss of proteoglycan content. This then corresponds with MRI changes associated with the loss of proteoglycan content. Patients with patellofemoral pain and maltracking have been demonstrated to have significantly greater T1rho relaxation times in the lateral facet of the patella when compared to healthy volunteers.
Time frame: 12 Months
MRI Muscle Volume
Quadriceps muscle volume (cm2)
Time frame: 12 Months
The Norwich Patellar Instability Scale
The Norwich Patellar Instability (NPI) Scale is a 19-item scale that asks subjects to rate their perceived patellar instability during different tasks, and has been demonstrated to be a valid and responsive tool for assessing patient-reported outcomes for those being treated conservatively or surgically following patellar dislocation. The NPI is scored on a scale of 0 to 100, with lower scores being indicative of less perceived instability
Time frame: 24 Months
Quadriceps Strength Symmetry
Isokinetic Dynamometer will be used. The primary analysis may include the comparison of these observations over multiple time points, with a particular interest in whether there are between-group or within-patient differences.
Time frame: 24 Months
MRI Muscle Volume
Quadriceps muscle volume (cm2)
Time frame: 24 Months
MRI T1rho
Increased T1rho relaxation times have been associated with loss of proteoglycan content. This then corresponds with MRI changes associated with the loss of proteoglycan content. Patients with patellofemoral pain and maltracking have been demonstrated to have significantly greater T1rho relaxation times in the lateral facet of the patella when compared to healthy volunteers.
Time frame: 24 Months
Plan to share: No
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