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NCT Number: NCT03042559

Protonics Knee Brace Versus Hamstring Resisted Exercise (HRE) on Individuals With Patellofemoral Pain Syndrome

ProtonicsTM Knee brace has been suggested as an intervention for patients with patellofemoral pain syndrome (PFPS). However, the effectiveness of this knee brace compared to traditional conservative methods knee rehabilitation is lacking. The objective of this randomized controlled trial was to compare the effect of ProtonicsTM knee brace vs. sports cord on knee pain and function in patients with PFPS.

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Key information

Conditions

Patellofemoral Pain Syndrome Joint Diseases Musculoskeletal Diseases

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Loma Linda University Health

Loma Linda, California, 92354, United States

About this study

The purpose of this graduate student research study was to compare the effect of ProtonicsTM knee brace vs. sports cord on knee pain and function in patients with PFPS.

Design: Randomized controlled trial.

Setting: Loma Linda University.

Participants: Subjects with patellofemoral pain will participate in the study.

Intervention: Subjects will be randomized to one of two treatment groups, the ProtonicsTM knee brace or the sport cord to complete a series of resistance exercises over the course of 4 weeks.

Main Outcome Measures: Both groups will be evaluated according to the following clinical outcomes: Anterior pelvic tilt (APT), hip internal/external rotation, and iliotibial band flexibility. The following functional outcomes were also assessed: Global Rating of Change (GROC) scale, the Kujala score, the Numeric Pain Rating Scale, and the lateral step-down test.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Subjects will be males and females who have Patellofemoral pain symptoms for more than 1 month, have pain level ≥ 3 on a Numeric Pain Rating Scale, and pain during at least 2 activities, such as squatting, ascending/descending stairs, and/or running.

Exclusion criteria

  • Subjects will be excluded if they have previous traumatic injuries to the knee joint/lower limbs, sign, and symptoms of meniscus tear or ligamentous-related pathology, neurological disorders and being on pain medication."

Treatment and study plan

Protonics Knee brace

Device

The Protonics system has been introduced to physical therapists as a potential treatment for PFPS. The system includes a brace set to resist knee flexion and a set of specific exercises to perform daily. Through resistance to knee flexion, the system is advertised to decrease retropatellar contact pressure due to changes in pelvis inclination and available hip rotation. Specifically, resistance to knee flexion is purported to increase hamstring activity and inhibit the activity of the tensor fasciae latae and psoas muscles. The manufacturer asserts that prolonged use of the system results in greater hamstring activation, which leads to permanent structural changes through reciprocal inhibition at the hip and pelvis. The warm-up consisted of the subject wearing the ProtonicsTM knee brace set at a moderate resistance level and flexing the knees while sitting, standing, and reclining in the supine and prone positions.

Sports Cords

Device

Subjects assigned to the sport cord group were asked to do the same warm-ups and exercises using the sport cord in the supine, standing, sitting, and prone positions. prone. The only difference is that subjects were asked to only walk backwards instead of forwards in order to avoid activation of the hip flexor muscle. The appropriate level of resistance for each subject was calculated by multiplying their weight in pounds by 0.3. Subjects were then given either light, medium, or heavy resistance cords according to the following classification scheme: light (pink color) with resistance 3 (R3), 0-30 lbs.; medium (orange color) with resistance 5 (R5) 0-50 lbs.; heavy (yellow color) with resistance 7 (R7) 0-70 lbs. All subjects completed three study visits, and a total of four measurements were taken at baseline, immediately following the first session, at two weeks, and at 4 weeks.

Primary outcomes

  1. Anterior Pelvic Tilt

    Time frame: Baseline to Post intervention

    Anterior Pelvic Tilt: tilting of the pelvic will be measured with CHEK inclinometer. Tilting will be measured while subjects are in a standing position. The examiner will determine the two measure line marks, anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS) to find the oblique angle of the pelvic.

    Normative values from other study that we will be using to compare anterior pelvic tilt: Male = 9° and Female = 12° (from Nguyen study in 2007).

    The CHEK inclinometer caliper has two arms; one arm will be placed on ASIS (front of pelvis) while the other on the PSIS (back of pelvis). The angle of the caliper will be determined to record the degree of anterior pelvic tilt.

    Baseline measurement to Post-intervention measurement = Four (4) weeks.

  2. Anterior Pelvic Tilt

    Time frame: 2 weeks

    Anterior Pelvic Tilt: tilting of the pelvic will be measured with CHEK inclinometer. Tilting will be measured while subjects are in a standing position. The examiner will determine the two measure line marks, anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS) to find the oblique angle of the pelvic. Approximate normally anterior pelvic tilt for male is 9° and for female is about 12° (Nguyen, 2007). The caliper has two arms; one arm will be placed on ASIP while the other on the PSIS. The angle of the caliper will be determined to record the degree of anterior pelvic tilt.

  3. Anterior Pelvic Tilt

    Time frame: 4 weeks

    Anterior Pelvic Tilt: tilting of the pelvic will be measured with CHEK inclinometer. Tilting will be measured while subjects are in a standing position. The examiner will determine the two measure line marks, anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS) to find the oblique angle of the pelvic. Approximate normally anterior pelvic tilt for male is 9° and for female is about 12° (Nguyen, 2007). The caliper has two arms; one arm will be placed on ASIP while the other on the PSIS. The angle of the caliper will be determined to record the degree of anterior pelvic tilt.

  4. Numeric Pain Rating Scale (NPRS)

    Time frame: baseline

    The Numerical Pain Rating Scale (NPRS) is a subjective measure in which individuals rate their pain on an eleven-point numerical scale. The scale is composed of 0 (no pain at all) to 10 (worst imaginable pain).

  5. Numeric Pain Rating Scale (NPRS)

    Time frame: Immediately following 1st session

    Used to assess pain level throughout the intervention. Scale: 0-10. Scoring: 0 (no pain) to 10 (worst, imaginable pain).

  6. Numeric Pain Rating Scale (NPRS)

    Time frame: 2 weeks

    The Numerical Pain Rating Scale (NPRS) is a subjective measure in which individuals rate their pain on an eleven-point numerical scale. The scale is composed of 0 (no pain at all) to 10 (worst imaginable pain).

  7. Numeric Pain Rating Scale (NPRS)

    Time frame: 4 weeks

    Used to assess pain level throughout the intervention. Scale: 0-10. Scoring: 0 (no pain) to 10 (worst, imaginable pain).

  8. Global Rating of Change (GROC)

    Time frame: Immediately following 1st session

    GROC scales offer a flexible, quick, and simple method of charting self-assessed clinical progress in research and clinical settings. 15-Point: Scale -7 to 0 to +7. A score of 0 = No change, +1 to +3 = small positive change, +4 to +5 = Moderate positive change, +6 to +7 = Large positive change. All negative scores (minus numbers) represent a poor outcome (-7 being the worst possible outcome).

  9. Global Rating of Change (GROC)

    Time frame: 2 weeks

    GRC scales offer a flexible, quick, and simple method of charting self-assessed clinical progress in research and clinical settings. It ranges from -7 to 7, in which item -7 represent very great deal worse, 0 represent no change in progress, and 7 exemplify a very great better.

  10. Global Rating of Change (GROC)

    Time frame: 4 weeks

    GRC scales offer a flexible, quick, and simple method of charting self-assessed clinical progress in research and clinical settings. It ranges from -7 to 7, in which item -7 represent very great deal worse, 0 represent no change in progress, and 7 exemplify a very great better.

  11. Kujala Score

    Time frame: baseline

    A self-report questionnaire, which is used to evaluate subjective symptoms and functional limitations in subjects with PFPS with a score range between of 0 - 100 based on pain associated with variety of functional activities such as prolonged sitting, squatting, running, and jumping. A score close to 100 indicates a higher functional performance. A score close to 0 represents a low level of function. Kujala scale has shown acceptable test-retest reliability (rho = 0.86) (Paxon et al, 2003). Kujala scale scores will be documented at the beginning and end of the intervention program.

  12. Kujala Score

    Time frame: 4 weeks

    A self-report questionnaire, which is used to evaluate subjective symptoms and functional limitations in subjects with PFPS with a score range between of 0 - 100 based on pain associated with variety of functional activities such as prolonged sitting, squatting, running, and jumping. A score close to 100 indicates a higher functional performance. Kujala scale has shown acceptable test-retest reliability (rho = 0.86) (Paxon et al, 2003). Kujala scale scores will be documented at the beginning and end of the intervention program.

  13. Lateral Step-Down Test

    Time frame: baseline

    Lateral step test: is a quick and simple practical clinical measure of functional. Subjects with PFPS will be asked to step up and down on a 15-cm step for 15 seconds each with a cadence of 2 steps per second. The total number of step-ups during this time will be recorded. Subjects will be asked to report a verbal pain score during the step-up test at each test session. This test will be performed every two weeks to document any improvement in the functional performance. The test has shown to be reliable and valid, with test-retest reliability of (ICC = 0.90) (Ross et al, 1997).

  14. Lateral Step-Down Test

    Time frame: Immediately following 1st session

    Lateral step test: is a quick and simple practical clinical measure of functional. Subjects with PFPS will be asked to step up and down on a 15-cm step for 15 seconds each with a cadence of 2 steps per second. The total number of step-ups during this time will be recorded. Subjects will be asked to report a verbal pain score during the step-up test at each test session. This test will be performed every two weeks to document any improvement in the functional performance. The test has shown to be reliable and valid, with test-retest reliability of (ICC = 0.90) (Ross et al, 1997).

  15. Lateral Step-Down Test

    Time frame: 2 weeks

    Lateral step test: is a quick and simple practical clinical measure of functional. Subjects with PFPS will be asked to step up and down on a 15-cm step for 15 seconds each with a cadence of 2 steps per second. The total number of step-ups during this time will be recorded. This test will be performed every two weeks to document any improvement in the functional performance. The test has shown to be reliable and valid, with test-retest reliability of (ICC = 0.90) (Ross et al, 1997).

  16. Lateral Step-Down Test

    Time frame: 4 weeks

    Lateral step test: is a quick and simple practical clinical measure of functional. Subjects with PFPS will be asked to step up and down on a 15-cm step for 15 seconds each with a cadence of 2 steps per second. The total number of step-ups during this time will be recorded. This test will be performed every two weeks to document any improvement in the functional performance. The test has shown to be reliable and valid, with test-retest reliability of (ICC = 0.90) (Ross et al, 1997).

Secondary outcomes

  1. Iliotibial Band Flexibility

    Time frame: baseline

    To assess the flexibility of iliotibial band

  2. Iliotibial Band Flexibility

    Time frame: Immediately following 1st session

    To assess the flexibility of iliotibial band

  3. Iliotibial Band Flexibility

    Time frame: 2 weeks

    To assess the flexibility of iliotibial band

  4. Iliotibial Band Flexibility

    Time frame: 4 weeks

    To assess the flexibility of iliotibial band

  5. Hip Internal Rotation ROM

    Time frame: baseline

    To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  6. Hip Internal Rotation ROM

    Time frame: Immediately following 1st session

    To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  7. Hip Internal Rotation ROM

    Time frame: 2 weeks

    To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  8. Hip Internal Rotation ROM

    Time frame: 4 weeks

    To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  9. Hip External Rotation ROM

    Time frame: baseline

    To measure the External rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  10. Hip External Rotation ROM

    Time frame: Immediately following 1st session

    To measure the External rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  11. Hip External Rotation ROM

    Time frame: 2 weeks

    To measure the external rotation of hip in sitting natural position with hip and knee on 90 degree flexion

  12. Hip External Rotation ROM

    Time frame: 4 weeks

    To measure the external rotation of hip in sitting natural position with hip and knee on 90 degree flexion

Sponsors and collaborators

Lead sponsor

Loma Linda University

Other

Registry information

Official study title

The Effects of Protonics Knee Brace Versus Hamstring Resisted Exercise on Individuals With Patellofemoral Pain Syndrome

Acronym: HRE

Important dates

Study start
2017
Primary completion
2018
Study completion
2018
First posted
Feb 3, 2017
Registry last updated
May 15, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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