Patellofemoral Pain Syndrome
Conditions
Keywords
Knee pain, Rehabilitation
Brief summary
Patellofemoral pain syndrome (PFPS) is a common knee disorder affecting physically active people. Despite the growing base of support for the early introduction of hip strengthening exercises into the rehabilitation of PFPS, there have been few randomized clinical trials comparing isolated hip to isolated quadriceps strengthening. The purpose of this study is to determine how different exercises affect pain, strength, muscle activity, and function in female subjects with patellofemoral pain. The researchers hypothesize that females diagnosed with PFPS who initially participate in a hip strengthening program will report a greater perceived level of function, greater strength, less pain, and improved neuromuscular activity than those who participate in a progressive quadriceps strengthening intervention.
Detailed description
Methods: Thirty-three females with PFPS will perform either initial hip strengthening (hip group) or initial quadriceps strengthening (quad group) for 4 weeks, prior to 4 weeks of a similar program of functional weight-bearing exercises. Self-reported pain, function, and functional strength were measured. Isometric strength was assessed for hip abductors, external rotators, and knee extensors. A mixed-model analysis of variance will be used to determine group differences over time.
Interventions
OTHERHip Progressive Resistive Exercise
Hip Progressive Resistance Exercise program will be carried out by subjects under supervision once a week and then performed at home 2 additional times at home without supervision. Exercises focus on strengthening hip abduction ad external rotation musculature.
OTHERQuad Progressive Resistive Exercises
Quad Progressive Resistive Exercise program will be carried out by subjects under supervision once a week and then performed at home 2 additional times at home without supervision. Exercises focus on strengthening quadriceps musculature with straight leg raises and quadriceps isometrics.
Sponsors
Timothy Uhl
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
FEMALE
Age
15 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* anterior or retropatellar knee pain reported during at least 2 of the following activities: ascending and descending stairs, hopping and running, squatting, kneeling, and prolonged sitting * insidious onset of symptoms not related to trauma * pain with compression of the patella * pain on palpation of the patellar facets
Exclusion criteria
* symptoms present for less than one month * clinical evidence of other knee pathology * history of recent knee surgery within past one year * history of patellar dislocations or subluxations * current significant injury affecting other lower extremity joints
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Visual Analog Pain Scale | 8 week | Visual analog pain scale at end of intervention. 0 to 10 cm line with 0 representing no pain and 10 representing severe pain |
| Visual Analog Pain Scale (Describing Worst Pain Felt During the Past Week) | weekly | 0 to 10 cm line with 0 representing no pain and 10 representing severe pain |
| Subjective Function by Lower Extremity Functional Scale Report Form | Baseline, Mid-Intervention, and Post-Intervention | — |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Strength by Isometric Dynamometer | Baseline, Mid, and Post-Intervention | — |
| Hip Abduction Strength | 8 week | Side lying Hip Abduction maximal muscular contraction with a hand held dynamometer |
| Neuromuscular Activity by Surface Electromyographical Amplitude During Stair Descent | Baseline, Mid and Post-Intervention | — |
| Objective Function by Step-down Task for 30 Seconds | Baseline, Mid, and Post-Intervention | — |
Countries
United States
Participant flow
Recruitment details
33 females with anterior knee pain (PFPS) volunteered to participate in this study. Enrollment began August 2007 and last subject was enrolled in August 2009.
Pre-assignment details
Subjects were evaluated for PFPS using the following:(1)anterior knee pain reported during at least 2 activities: stair climbing, running, squatting, kneeling, and prolonged sitting;(2)insidious onset of symptoms ;(3)pain with compression of the patella; and(4)pain on palpation of patellar facets. Only three patients were excluded during study.
Participants by arm
| Arm | Count |
|---|---|
| Hip Strengthening Then Combined Exercises Performed hip strengthening exercises for 4 weeks prior to crossing over to a combined hip and quadricep rehabilitation program | 17 |
| Quadricep Group Then Combined Exercises Performed quadricep strengthening exercises for 4 weeks prior to crossing over to a combined hip and quadricep rehabilitation program | 16 |
| Total | 33 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Specific Exercises | Withdrawal by Subject | 3 | 3 |
Baseline characteristics
| Characteristic | Quadricep Group Then Combined Exercises | Hip Strengthening Then Combined Exercises | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 16 Participants | 17 Participants | 33 Participants |
| Age, Continuous | 25.7 years STANDARD_DEVIATION 5.9 | 24.6 years STANDARD_DEVIATION 5.3 | 25 years STANDARD_DEVIATION 5.5 |
| Region of Enrollment United States | 16 participants | 17 participants | 33 participants |
| Sex: Female, Male Female | 16 Participants | 17 Participants | 33 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 17 | 0 / 16 |
| serious Total, serious adverse events | 0 / 17 | 0 / 16 |
Outcome results
Primary
Subjective Function by Lower Extremity Functional Scale Report Form
Time frame: Baseline, Mid-Intervention, and Post-Intervention
Primary
Visual Analog Pain Scale
Visual analog pain scale at end of intervention. 0 to 10 cm line with 0 representing no pain and 10 representing severe pain
Time frame: 8 week
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hip Strengthening Then Combined Exercises | Visual Analog Pain Scale | 2.4 centimeters | Standard Deviation 2.8 |
| Quadricep Group Then Combined Exercises | Visual Analog Pain Scale | 2.6 centimeters | Standard Deviation 2 |
Comparison: Repeated measures ANOVA for group and timep-value: 0.049ANOVA
Primary
Visual Analog Pain Scale (Describing Worst Pain Felt During the Past Week)
0 to 10 cm line with 0 representing no pain and 10 representing severe pain
Time frame: weekly
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hip Strengthening Then Combined Exercises | Visual Analog Pain Scale (Describing Worst Pain Felt During the Past Week) | 4.5 centimeter | Standard Deviation 2.5 |
| Quadricep Group Then Combined Exercises | Visual Analog Pain Scale (Describing Worst Pain Felt During the Past Week) | 4.2 centimeter | Standard Deviation 2.2 |
Secondary
Hip Abduction Strength
Side lying Hip Abduction maximal muscular contraction with a hand held dynamometer
Time frame: 8 week
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hip Strengthening Then Combined Exercises | Hip Abduction Strength | 6.6 (Newton*meters)/(Weight*Height) | Standard Deviation 0.9 |
| Quadricep Group Then Combined Exercises | Hip Abduction Strength | 6.2 (Newton*meters)/(Weight*Height) | Standard Deviation 1.8 |
p-value: 0.041ANOVA
Secondary
Neuromuscular Activity by Surface Electromyographical Amplitude During Stair Descent
Time frame: Baseline, Mid and Post-Intervention
Secondary
Objective Function by Step-down Task for 30 Seconds
Time frame: Baseline, Mid, and Post-Intervention
Secondary
Strength by Isometric Dynamometer
Time frame: Baseline, Mid, and Post-Intervention