Exploration of Gait Biomechanics and Muscle Pain of the Lower Extremity

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.

Study Overview

• Status: Recruiting
• Conditions: Pain, Acute
• Intervention / Treatment: Other: Hypertonic saline injection; Other: Isotonic saline injection

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.

• Study Type: Interventional
• Enrollment (Estimated): 36
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Kristian KS Petersen; Phone Number: 31697510; Email: kkp@hst.aau.dk
• Study Contact Backup: Name: Emma Hertel; Phone Number: 60887473; Email: eh@hst.aau.dk

Study Locations

• Denmark
  • Nordjylland
    • Aalborg, Nordjylland, Denmark, 9000
      • Recruiting
      • Aalborg University
      • Contact: Kristian KS Petersen; Phone Number: 31697510; Email: kkp@hst.aau.dk
      • Contact: Emma Hertel; Phone Number: 60887473; Email: eh@hst.aau.dk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy men and women aged 18-45 years

Exclusion Criteria:

• 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 Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Gastrocnemius (painful condition); 1.5 mL injection of hypertonic saline (7%) to the gastrocnemius muscle.	Other: Hypertonic saline injection; Injection with hypertonic saline (7%)
Sham Comparator: Gastrocnemius (control condition); 1.5 mL injection of isotonic saline (0.9%) to the gastrocnemius muscle.	Other: Isotonic saline injection; Injection with isotonic saline (0.9%)
Experimental: Semitendinosus (painful condition); 1.2 mL injection of hypertonic saline (7%) to the semitendinosus muscle.	Other: Hypertonic saline injection; Injection with hypertonic saline (7%)
Sham Comparator: Semitendinosus (control condition); 1.2 mL injection of isotonic saline (7%) to the semitendinosus muscle.	Other: Isotonic saline injection; Injection with isotonic saline (0.9%)
Experimental: Biceps femoris (painful condition); 1.2 mL injection of hypertonic saline (7%) to the biceps femoris muscle.	Other: Hypertonic saline injection; Injection with hypertonic saline (7%)
Sham Comparator: Biceps femoris (control condition); 1.2 mL injection of isotonic saline (0.9%) to the biceps femoris muscle.	Other: Isotonic saline injection; Injection with isotonic saline (0.9%)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Infrared marker XYZ coordinates	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.	Baseline.
Pain intensity (NRS 0-10)	Pain during intervention is measured continuously every 30 seconds on a numeric rating scale from 0 'no pain' to 10 'the worst pain imaginable'	Baseline.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain sensitivity.	Cuff-pressure algometry will be used to estimate pressure detection and tolerance thresholds, temporal summation of pain, and conditioned pain modulation.	Baseline.
Ground reaction forces	Ground reaction forces will be measured in Newtons with force plates embedded in the floor.	Baseline.
Ground reaction moments	Ground reaction moments will be measured in Newton-meters with force plates embedded in the floor.	Baseline.
Ground contact XZ location	Ground contact XZ coordinate location will be measured in millimeters with force plates embedded in the floor.	Baseline.
Muscle activation	Muscle activation will be measured in micro-volts using wireless EMG on the muscles of the lower extremities.	Baseline.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain during jumping	Pain during jumping is captured on a numeric rating scale from 0 'no pain' to 10 'the worst pain imaginable'	Baseline

Collaborators and Investigators

• Sponsor: Kristian Kjær Petersen
• Investigators: Principal Investigator: Kristian KS Petersen, Aalborg University

Study record dates

Study Major Dates

• Study Start (Actual): November 8, 2023
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: May 8, 2024
• First Submitted That Met QC Criteria: May 8, 2024
• First Posted (Actual): May 13, 2024

Study Record Updates

• Last Update Posted (Actual): May 16, 2024
• Last Update Submitted That Met QC Criteria: May 14, 2024
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Keywords: Biomechanics; Healthy Participants; Musculoskeletal pain
• Additional Relevant MeSH Terms: Nervous System Diseases; Pain; Neurologic Manifestations; Musculoskeletal Diseases; Muscular Diseases; Neuromuscular Diseases; Musculoskeletal Pain; Myalgia; Acute Pain
• Other Study ID Numbers: N-20220063-2

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No