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Eccentric/Concentric torque deficits in the quadriceps muscle
The Journal of Orthopaedic and Sports Physical Therapy
|January 1, 1989
Summary
Many healthy individuals have an eccentric/concentric torque deficit in leg extension. This finding challenges previous research linking this deficit to anterior knee pain and its treatment.
Area of Science:
- Biomechanics
- Sports Medicine
- Orthopedics
Background:
- Eccentric and concentric torque deficits are often assessed in clinical settings.
- Previous research suggests a link between these deficits and anterior knee pain.
Purpose of the Study:
- To determine the prevalence of eccentric/concentric torque deficits in asymptomatic individuals.
- To evaluate the functional implications of these deficits in a healthy population.
Main Methods:
- 105 asymptomatic subjects (mean age 23.51) were tested.
- Maximum eccentric and concentric torque during leg extension was measured using a KIN-COM dynamometer.
- Testing involved an 80-degree range of motion at 50 degrees/sec velocity.
Main Results:
- 35-54% of asymptomatic subjects exhibited an eccentric/concentric torque deficit.
- The prevalence varied based on sex and the leg tested.
- A deficit was defined as eccentric torque being ≤85% of concentric torque at any point in the range of motion.
Conclusions:
- A significant percentage of asymptomatic individuals possess eccentric/concentric torque deficits.
- These findings raise questions about the clinical validity of previous research on anterior knee pain.
- The assumption that correcting such deficits alleviates pain may need re-evaluation.
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