Achilles Tendon Pain
Conditions
Keywords
Human, Pain, Biomechanics, Anesthetics
Brief summary
The purpose of this study is to better understand how the peripheral and central nervous system interact to produce the sensation of pain and motor patterns in patients with achilles tendinopathy (AT). These findings will motivate the development of future clinical studies that incorporate knowledge about pain processing and movement strategies in patients with tendinopathy. Participants with achilles tendinopathy will receive an anesthetic injection to the achilles tendon in order to examine how reduced pain, detected by the peripheral nervous system, alters task performance and perception of pain. We hypothesize that there are factors within the central nervous system that contribute to continued pain and disability in patients with chronic AT.
Detailed description
Twenty three people with Achilles tendinopathy (AT) and 23 people without AT will participate in this single visit clinical study. Participants will rate their pain with pressure to the heel, leg and elbow, climb stairs and perform a novel task in a motion capture system, and complete questionnaires on how pain affects their daily life. All subjects will complete these measures twice, and for participants with AT they will complete this battery of tests before and after an anesthetic injection to the area of pain. This study has 2 aims: Specific Aim 1 compares measures of altered central processing in patients with chronic AT to adults without chronic pain; we hypothesize that patients with chronic AT will demonstrate signs of altered central processing, including central sensitization (lower pressure pain threshold), psychosocial factors (higher kinesiophobia), and/or altered motor control (lower ankle power during stair ascent). Specific Aim 2 determines which indicators of altered central processing persist after a local anesthetic injection to the Achilles tendon in patients with chronic AT; we hypothesize chronic AT pain is perpetuated by altered central processing that persists in the absence of continued peripheral nociception.
Interventions
DRUGRopivacaine injection
single dose, subcutaneous injection
Sponsors
Ruth Chimenti
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
In this mechanistic study, the Achilles tendinopathy group receives an anesthetic injection. The healthy control group does not receive an injection.
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
For patients with AT Inclusion Criteria: \- Clinical diagnosis of chronic (\>3 months) AT, consisting of pain with pressure at the achilles tendon and report of pain that is aggravated by physical activity
Exclusion criteria
* History of foot or ankle surgery, bilateral lateral epicondyle tendinopathy * Comorbidity that would be aggravated by placing hand in water (Raynaud's, thoracic outlet syndrome) * Comorbidity (e.g. stroke, neurological disorder) that limits ability to participate in exercise * Comorbidity (e.g. rheumatic disease, fibromyalgia) that contributes to pain with activity * Peripheral neuropathy * Previous adverse response to a local anesthetic injection * Are pregnant * Are a ballroom dancer For control participants Inclusion Criteria: \- Sex, Age and BMI-matched to participant with AT
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Central Sensitization | Within session, baseline and 30 minutes after an anesthetic injection | Pressure pain threshold (PPT) at heel on contralateral side. A pressure algometer (Somedic, Farsta, Sweden) was applied perpendicular to the skin at a rate of 50 kilopascal/s with a 1cm2 tip. The participants pressed a button when the sensation of pressure first became painful (1/10 on NPRS). The mean of 3 trials per area represented the PPT. |
| Pain Psychology | Within session, baseline and 30 minutes after an anesthetic injection | Tampa Scale of Kinesiophobia (TSK, score range 17 to 68). A decrease in TSK would indicate a decrease in fear of injury (and/or re-injury) |
| Movement System | Within session, baseline and 30 minutes after an anesthetic injection | Change in peak ankle power during the stance phase of gait during stair ascent, which will be assessed by syncing movement data from 3-dimensional motion analysis with ground reaction force data from a force plate. Peak positive ankle power reflects the ability of the plantar flexor muscles to concentrically generate speed and force at the ankle joint. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Group With Achilles Tendinopathy Ropivacaine injection. While looking at the Achilles tendon with ultrasound, the orthopaedic physician will inject 4 mL of 0.5% ropivacaine (numbing medicine) around the area of pain. The needle may be directed just under the skin (and above the tendon) and/or deep to the tendon.
Ropivacaine injection: single dose, subcutaneous injection | 23 |
| Group Without Achilles Tendinopathy This group did not receive an injection prior to repeating the set of tests within session. | 23 |
| Total | 46 |
Baseline characteristics
| Characteristic | Group With Achilles Tendinopathy | Total | Group Without Achilles Tendinopathy |
|---|---|---|---|
| Age, Continuous | 49.5 years STANDARD_DEVIATION 10.3 | 49.4 years STANDARD_DEVIATION 10.5 | 49.2 years STANDARD_DEVIATION 10.6 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 2 Participants | 2 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 21 Participants | 42 Participants | 21 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 2 Participants | 2 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 2 Participants | 3 Participants | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 4 Participants | 4 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 19 Participants | 37 Participants | 18 Participants |
| Region of Enrollment United States | 23 Participants | 46 Participants | 23 Participants |
| Sex: Female, Male Female | 15 Participants | 30 Participants | 15 Participants |
| Sex: Female, Male Male | 8 Participants | 16 Participants | 8 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 23 | 0 / 23 |
| other Total, other adverse events | 2 / 23 | 0 / 23 |
| serious Total, serious adverse events | 0 / 23 | 0 / 23 |
Outcome results
Primary
Central Sensitization
Pressure pain threshold (PPT) at heel on contralateral side. A pressure algometer (Somedic, Farsta, Sweden) was applied perpendicular to the skin at a rate of 50 kilopascal/s with a 1cm2 tip. The participants pressed a button when the sensation of pressure first became painful (1/10 on NPRS). The mean of 3 trials per area represented the PPT.
Time frame: Within session, baseline and 30 minutes after an anesthetic injection
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Group With Achilles Tendinopathy | Central Sensitization | Before Anesthetic Injection | 463.5 kilopascal |
| Group With Achilles Tendinopathy | Central Sensitization | After Anesthetic Injection | 425.7 kilopascal |
| Group Without Achilles Tendinopathy | Central Sensitization | Before Anesthetic Injection | 383.6 kilopascal |
| Group Without Achilles Tendinopathy | Central Sensitization | After Anesthetic Injection | 358.0 kilopascal |
Comparison: Specific Aim 1: Between groupsp-value: 0.44ANOVA
Comparison: Specific Aim 2: Effect of timep-value: 0.08ANOVA
Primary
Movement System
Change in peak ankle power during the stance phase of gait during stair ascent, which will be assessed by syncing movement data from 3-dimensional motion analysis with ground reaction force data from a force plate. Peak positive ankle power reflects the ability of the plantar flexor muscles to concentrically generate speed and force at the ankle joint.
Time frame: Within session, baseline and 30 minutes after an anesthetic injection
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Group With Achilles Tendinopathy | Movement System | Before Anesthetic Injection | 2.7 Watts/kg |
| Group With Achilles Tendinopathy | Movement System | After Anesthetic Injection | 2.8 Watts/kg |
| Group Without Achilles Tendinopathy | Movement System | Before Anesthetic Injection | 3.0 Watts/kg |
| Group Without Achilles Tendinopathy | Movement System | After Anesthetic Injection | 2.8 Watts/kg |
Comparison: Specific Aim 1: Between groupsp-value: 1ANOVA
Comparison: Specific Aim 2: Effect of timep-value: 1ANOVA
Primary
Pain Psychology
Tampa Scale of Kinesiophobia (TSK, score range 17 to 68). A decrease in TSK would indicate a decrease in fear of injury (and/or re-injury)
Time frame: Within session, baseline and 30 minutes after an anesthetic injection
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Group With Achilles Tendinopathy | Pain Psychology | After Anesthetic Injection | 34.9 units on a scale |
| Group With Achilles Tendinopathy | Pain Psychology | Before Anesthetic Injection | 37.2 units on a scale |
| Group Without Achilles Tendinopathy | Pain Psychology | Before Anesthetic Injection | 29.6 units on a scale |
| Group Without Achilles Tendinopathy | Pain Psychology | After Anesthetic Injection | 28.7 units on a scale |
Comparison: Specific Aim 1: Between groupsp-value: <0.001ANOVA
Comparison: Specific Aim 2: Effect of timep-value: 0.012ANOVA