The Acute Effects of an Isometric Loading Intervention on Lower Extremity Landing Biomechanics in Individuals With Patellar Tendinopathy

The Acute Effects of an Isometric Loading Intervention on Lower Extremity Landing Biomechanics in Individuals With Patellar Tendinopathy

The purpose of this study is to determine differences in lower extremity landing biomechanics and real-world physical activity between individuals with patellar tendinopathy compared to individuals without patellar tendinopathy,and to determine the acute effects of an isometric loading intervention on lower extremity landing biomechanics in individuals with patellar tendinopathy.

Inclusion Criteria:

The investigators will recruit a convenience sample of participants who meet the following overall criteria:

1. Age 15 and post-pubertal (confirmed by Pubertal Development Scale Questionnaire) - 28 years
2. Actively participating within an organized sport setting (high school, collegiate, club, competitive intramural sports) in their respective team's weekly training and competitions, quantified by a Tegner Activity Level Scale of at least 5.

Exclusion Criteria:

The following exclusion criteria will be applied to all participants:

1. Any anterior knee pain with no patellar tendon abnormality on ultrasound assessment.

2. History of any knee joint surgery ever.

3. History of other (non-knee) lower extremity surgery in the last 1 year.

4. History of lower extremity injury in last 6 months (other than patellar tendinopathy).

5. An injection (corticosteroids, plasma-rich-protein, etc.) to the patellar tendon in the last 3 months.

6. Known history of osteoarthritis or current symptoms related to osteoarthritis (i.e. stiffness, swelling).

7. Participation in formal rehabilitation for patellar tendinopathy in prior 3 months

8. Known neurological disorders, including: stroke, multiple sclerosis, ALS, diabetic neuropathy, epilepsy, traumatic brain injury resulting in loss of consciousness, concussion within the last 6 months, cranial neural surgery, balance disorders.

9. Use of pacemaker or another implantable electronic device.

10. History of cardiac arrhythmia or any cardiac condition.

11. History of psychiatric disorder. *

12. History of cancer in the brain or thigh musculature.

13. Pubertal Development Scale Score < 12 (Stages 1-4)

    • Note: Rationale for exclusion of individuals with a history of psychiatric disorders is that these individuals may have taken or be taking pharmacological agents that could affect pain or neuromuscular control.