Effects of Minimally Invasive Techniques in Healthy and Chronic Cervical Pain Individuals

Universidad Europea de Madrid60 enrolled

Overview

Brief Summary: This project consists of two sequential experimental phases designed to analyze the immediate and 24-hour effects of three invasive physiotherapy techniques -dry needling (DN), percutaneous neuromodulation (PENS), and percutaneous electrolysis (EPE)- on muscle tone and pain perception. In the first phase, the study will be conducted on healthy volunteers to assess the physiological responses and safety profile of the interventions under controlled conditions. Each participant will receive one of the three randomly assigned interventions (DN, PENS, or EPE), applied to the upper trapezius muscle. Pain perception (Visual Analog Scale, VAS) and muscle mechanical properties (tone, stiffness, and elasticity) will be measured before and after the intervention, and after 24 hours, using the MyotonPRO device. In the second phase, the same protocol and parameters will be applied to patients with chronic neck pain, in order to compare the magnitude and persistence of the effects between healthy subjects and symptomatic individuals. This study aims to improve understanding of the short-term physiological mechanisms of invasive physiotherapy techniques and their relative effectiveness in managing chronic neck pain. The findings will contribute to the development of more precise and evidence-based treatment protocols for musculoskeletal pain.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

Conditions

Chronic Neck Pain

Interventions

Dry needlingPROCEDURE

Dry needling will be performed on the upper trapezius muscle at an active myofascial trigger point. A sterile, single-use solid filament needle (0.30 × 40 mm) will be inserted until eliciting three local twitch responses (LTRs). The needle will then be withdrawn immediately after obtaining the final response. The technique aims to normalize motor endplate activity and reduce local and referred pain through mechanical and neurophysiological modulation.

Percutaneous nerve stimulationPROCEDURE

Percutaneous neuromodulation will be applied using a sterile acupuncture needle (0.30 × 40 mm) inserted near the accessory nerve pathway in the upper trapezius region. A low-frequency alternating current (10 Hz, 250 μs pulse width) will be delivered for 15 minutes using an electrotherapy device approved for clinical use. The objective is to modulate neuromuscular excitability and decrease pain perception through peripheral and central mechanisms.

Percutaneous electrolysisPROCEDURE

Percutaneous electrolysis will be performed by inserting a sterile acupuncture needle (0.30 × 40 mm) into the active myofascial trigger point of the upper trapezius. A galvanic current of 1 mA will be applied for three impacts of 5 seconds each using an approved electrolysis device. This technique produces a controlled local inflammatory response, promoting tissue regeneration and analgesia through electrochemical and neurophysiological effects.

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

INCLUSION CRITERIA Phase 1 - healthy subjects 1. Age between 18 and 65 years. 2. Healthy individuals without any current musculoskeletal or neurological pathology. 3. Presence of a palpable myofascial trigger point in the upper trapezius muscle. 4. No neck or shoulder pain requiring medical treatment in the past three months. 5. Willingness to refrain from other physiotherapy or manual therapy interventions during the study period. 6. Ability to understand and provide written informed consent Phase 2 - Patients with Chronic Neck Pain 1. Age between 18 and 65 years. 2. Diagnosis of chronic mechanical or tension-type neck pain lasting for at least 3 months. 3. Presence of at least one active myofascial trigger point in the upper trapezius muscle. 4. Pain intensity between 3 and 7 on a 10-cm Visual Analog Scale (VAS) at baseline. 5. No previous invasive physiotherapy treatments (dry needling, electrolysis, or neuromodulation) within the last 4 weeks. 6. Ability and willingness to attend all study sessions and follow-up assessments. 7. Signed informed consent before participation. EXCLUSION CRITERIA 1. History of cervical or shoulder surgery. 2. Neurological, systemic, or rheumatologic disorders affecting the cervical or upper limb region. 3. Anticoagulant therapy or known bleeding disorders. 4. Pregnancy or suspected pregnancy. 5. Skin infection, wound, or dermatological condition at or near the intervention site. 6. Use of analgesic, anti-inflammatory, or muscle relaxant medications within 48 hours prior to the intervention. 7. Prior invasive physiotherapy (dry needling, PENS, or EPE) in the target area during the past month. 8. Contraindications to electrical stimulation (for PENS or EPE groups), such as implanted pacemaker or metal implants near the treatment area. 9. Fear of needles (trypanophobia) or intolerance to invasive procedures. 10. Participation in another clinical trial within the past 3 months. 11. Refusal or inability to provide informed consent

Outcomes

Primary Outcomes

Pain intensity

Pain perception will be measured using a 10 cm Visual Analog Scale (VAS), where 0 indicates no pain and 10 indicates worst imaginable pain. Participants will mark their perceived pain intensity at rest. The scale is a reliable and validated tool for assessing subjective pain in musculoskeletal disorders.

Time frame: Baseline (pre-intervention), immediately post-intervention, and 24 hours post-intervention.

Secondary Outcomes

Muscle tone

Muscle tone will be assessed using the MyotonPRO device, which measures the natural oscillation frequency (Hz) of the muscle at rest. The upper trapezius will be evaluated at a standardized point corresponding to the active myofascial trigger point region. Higher frequency values indicate increased muscle tone.

Time frame: Baseline and immediately post-intervention, and 24 hours post-intervention

Muslce stiffness

Muscle stiffness will be evaluated using the MyotonPRO, which calculates the muscle's resistance to deformation expressed in newtons per meter (N/m). This parameter reflects the biomechanical rigidity of the tissue.

Time frame: Baseline, immediately post intervention and 24 hours post-intervention

Muscle elasticity

Elasticity will be measured with the MyotonPRO, expressed as the logarithmic decrement of the muscle's oscillation. Lower values indicate greater elasticity and better recovery capacity after deformation.

Time frame: Baseline, immedialely post intervention and 24 hours post intervention