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

The Effects of Protonics Knee Brace Versus Hamstring Resisted Exercise 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.

Study Overview

• Status: Completed
• Conditions: Patellofemoral Pain Syndrome
• Intervention / Treatment: Device: Protonics Knee brace; Device: Sports Cords

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Actual): 43
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Loma Linda, California, United States, 92354
      • Loma Linda University Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 41 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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."

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Protonics knee brace; All subjects were fitted with a regular-sized Protonics knee brace with resistive settings to resist knee flexion.	Device: Protonics Knee brace; 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.
Experimental: Sport cords; Resistive sports cord to resist knee flexion.	Device: Sports Cords; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anterior Pelvic Tilt	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.	Baseline to Post intervention
Anterior Pelvic Tilt	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.	2 weeks
Anterior Pelvic Tilt	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 weeks
Numeric Pain Rating Scale (NPRS)	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).	baseline
Numeric Pain Rating Scale (NPRS)	Used to assess pain level throughout the intervention. Scale: 0-10. Scoring: 0 (no pain) to 10 (worst, imaginable pain).	Immediately following 1st session
Numeric Pain Rating Scale (NPRS)	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).	2 weeks
Numeric Pain Rating Scale (NPRS)	Used to assess pain level throughout the intervention. Scale: 0-10. Scoring: 0 (no pain) to 10 (worst, imaginable pain).	4 weeks
Global Rating of Change (GROC)	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).	Immediately following 1st session
Global Rating of Change (GROC)	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.	2 weeks
Global Rating of Change (GROC)	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.	4 weeks
Kujala Score	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.	baseline
Kujala Score	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.	4 weeks
Lateral Step-Down Test	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).	baseline
Lateral Step-Down Test	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).	Immediately following 1st session
Lateral Step-Down Test	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).	2 weeks
Lateral Step-Down Test	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).	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Iliotibial Band Flexibility	To assess the flexibility of iliotibial band	baseline
Iliotibial Band Flexibility	To assess the flexibility of iliotibial band	Immediately following 1st session
Iliotibial Band Flexibility	To assess the flexibility of iliotibial band	2 weeks
Iliotibial Band Flexibility	To assess the flexibility of iliotibial band	4 weeks
Hip Internal Rotation ROM	To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion	baseline
Hip Internal Rotation ROM	To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion	Immediately following 1st session
Hip Internal Rotation ROM	To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion	2 weeks
Hip Internal Rotation ROM	To measure the internal rotation of hip in sitting natural position with hip and knee on 90 degree flexion	4 weeks
Hip External Rotation ROM	To measure the External rotation of hip in sitting natural position with hip and knee on 90 degree flexion	baseline
Hip External Rotation ROM	To measure the External rotation of hip in sitting natural position with hip and knee on 90 degree flexion	Immediately following 1st session
Hip External Rotation ROM	To measure the external rotation of hip in sitting natural position with hip and knee on 90 degree flexion	2 weeks
Hip External Rotation ROM	To measure the external rotation of hip in sitting natural position with hip and knee on 90 degree flexion	4 weeks

Collaborators and Investigators

• Sponsor: Loma Linda University

Publications and helpful links

General Publications

• Arroll B, Ellis-Pegler E, Edwards A, Sutcliffe G. Patellofemoral pain syndrome. A critical review of the clinical trials on nonoperative therapy. Am J Sports Med. 1997 Mar-Apr;25(2):207-12. doi: 10.1177/036354659702500212.
• Bockrath K, Wooden C, Worrell T, Ingersoll CD, Farr J. Effects of patella taping on patella position and perceived pain. Med Sci Sports Exerc. 1993 Sep;25(9):989-92.
• Callaghan MJ, Selfe J. Patellar taping for patellofemoral pain syndrome in adults. Cochrane Database Syst Rev. 2012 Apr 18;(4):CD006717. doi: 10.1002/14651858.CD006717.pub2.
• Azevedo DC, Santos H, Carneiro RL, Andrade GT. Reliability of sagittal pelvic position assessments in standing, sitting and during hip flexion using palpation meter. J Bodyw Mov Ther. 2014 Apr;18(2):210-4. doi: 10.1016/j.jbmt.2013.05.017. Epub 2013 Jun 17.
• Denton J, Willson JD, Ballantyne BT, Davis IS. The addition of the Protonics brace system to a rehabilitation protocol to address patellofemoral joint syndrome. J Orthop Sports Phys Ther. 2005 Apr;35(4):210-9. doi: 10.2519/jospt.2005.35.4.210.
• Earl JE, Piazza SJ, Hertel J. The Protonics Knee Brace Unloads the Quadriceps Muscles in Healthy Subjects. J Athl Train. 2004 Mar;39(1):44-49.
• Gajdosik RL, Sandler MM, Marr HL. Influence of knee positions and gender on the Ober test for length of the iliotibial band. Clin Biomech (Bristol, Avon). 2003 Jan;18(1):77-9. doi: 10.1016/s0268-0033(02)00168-7.

Study record dates

Study Major Dates

• Study Start (Actual): February 14, 2017
• Primary Completion (Actual): January 8, 2018
• Study Completion (Actual): January 8, 2018

Study Registration Dates

• First Submitted: January 30, 2017
• First Submitted That Met QC Criteria: February 1, 2017
• First Posted (Estimate): February 3, 2017

Study Record Updates

• Last Update Posted (Actual): May 15, 2020
• Last Update Submitted That Met QC Criteria: April 30, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Pathologic Processes; Disease; Joint Diseases; Musculoskeletal Diseases; Syndrome; Somatoform Disorders; Patellofemoral Pain Syndrome
• Other Study ID Numbers: 5160417

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes