Exploration of Gait Biomechanics and Muscle Pain of the Lower Extremity
- Conditions
- Pain, Acute
- Interventions
- Other: Isotonic saline injectionOther: Hypertonic saline injection
- Registration Number
- NCT06411197
- Lead Sponsor
- Kristian Kjær Petersen
- Brief Summary
This interventional study aims to test gait biomechanics in healthy individuals with and without experimental muscle pain in the lower extremities. The study aims to:
A) Examine how experimental muscle pain in different types of muscles (ankle plantar-flexion, knee extension, and flexion muscles) affects kinematics, kinetics, and muscle activation
Participants will receive six muscle injections: a) Hypertonic saline (painful condition) and b) Isotonic saline (control condition) in 1) m. gastrocnemius, 2) m. semitendinosus, and 3) m. biceps femoris.
- Detailed Description
The proposed study will be a randomized, crossover design in which experimental pain will be induced in healthy subjects using hypertonic saline injections to three muscles of the lower extremities: The gastrocnemius muscle, the vastus medialis muscle, and the semitendinosus muscle. Participants will be block-randomized to receive an injection in each of the three muscles and will receive either the painful or control condition first for each muscle. The participant will always be blinded to the type of injection received.
Following the injection, there will typically be a 15-minute window of pain (45). Within this timeframe, motion capture will be carried out for both the control and painful conditions. During motion capture, the participants will perform multiple walking trials of approximately 10 meters. The participants will be equipped with electromyography (EMG) sensors on key muscles of the lower extremities. The participants will be asked for NRS ratings every 30 seconds throughout the 15 minutes with expected pain. There will be a 15-minute washout between the muscle injections.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 36
- Healthy men and women aged 18-45 years
- Pregnancy
- Drug addiction, defined as the use of cannabis, opioids, or other drugs
- Previous or current neurologic or musculoskeletal illnesses
- Current pain
- Lack of ability to cooperate
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Biceps femoris (control condition) Isotonic saline injection 1.2 mL injection of isotonic saline (0.9%) to the biceps femoris muscle. Semitendinosus (painful condition) Hypertonic saline injection 1.2 mL injection of hypertonic saline (7%) to the semitendinosus muscle. Gastrocnemius (control condition) Isotonic saline injection 1.5 mL injection of isotonic saline (0.9%) to the gastrocnemius muscle. Biceps femoris (painful condition) Hypertonic saline injection 1.2 mL injection of hypertonic saline (7%) to the biceps femoris muscle. Semitendinosus (control condition) Isotonic saline injection 1.2 mL injection of isotonic saline (7%) to the semitendinosus muscle. Gastrocnemius (painful condition) Hypertonic saline injection 1.5 mL injection of hypertonic saline (7%) to the gastrocnemius muscle.
- Primary Outcome Measures
Name Time Method Infrared marker XYZ coordinates Baseline. Marker-based motion capture with infrared cameras will be used to estimate placement of reflective markers in the XYZ planes measured in millimeters. Reflective markers will be placed from head-to-toe on anatomical landmarks.
Pain intensity (NRS 0-10) Baseline. Pain during intervention is measured continuously every 30 seconds on a numeric rating scale from 0 'no pain' to 10 'the worst pain imaginable'
- Secondary Outcome Measures
Name Time Method Ground contact XZ location Baseline. Ground contact XZ coordinate location will be measured in millimeters with force plates embedded in the floor.
Ground reaction moments Baseline. Ground reaction moments will be measured in Newton-meters with force plates embedded in the floor.
Muscle activation Baseline. Muscle activation will be measured in micro-volts using wireless EMG on the muscles of the lower extremities.
Pain sensitivity. Baseline. Cuff-pressure algometry will be used to estimate pressure detection and tolerance thresholds, temporal summation of pain, and conditioned pain modulation.
Ground reaction forces Baseline. Ground reaction forces will be measured in Newtons with force plates embedded in the floor.
Trial Locations
- Locations (1)
Aalborg University
🇩🇰Aalborg, Nordjylland, Denmark