Magnesium Sulfate as an Adjuvant to Lidocaine in MPDS Trigger Point Injections Assessed by VAS and sEMG.

Cairo University28 enrolled

Overview

Two groups of patients diagnosed with Myofascial Pain Dysfunction Syndrome (MPDS) will be included in this study. One group will receive trigger point injections of lidocaine alone. The other group will receive trigger point injections of lidocaine combined with magnesium sulfate. The study aims to compare the effectiveness of both treatments in reducing pain and improving muscle function. Patients will be assessed using a pain scale (VAS) and surface electromyography (sEMG) to measure muscle activity.

This randomized clinical trial aims to evaluate whether adding magnesium sulfate to lidocaine in trigger point injections provides better pain relief and muscle relaxation in patients with Myofascial Pain Dysfunction Syndrome (MPDS) compared to lidocaine alone. Participants diagnosed with MPDS will be randomly assigned into one of two groups: Group 1 (Control Group): Trigger point injection of lidocaine 2% Group 2 (Intervention Group): Trigger point injection of lidocaine 2% combined with magnesium sulfate 10% Each participant will receive injections in the identified myofascial trigger points. Pain during injection and after injection will be assessed using the Visual Analog Scale (VAS). Muscle activity will be measured using surface electromyography (sEMG) at specific time points during rest and muscle contraction. The study will compare the changes in pain scores and EMG readings between the two groups to determine whether magnesium sulfate enhances the analgesic and muscle-relaxing effects of lidocaine. The results of this study may help improve treatment strategies for MPDS and provide evidence for using magnesium sulfate as an adjuvant to lidocaine in trigger point injections.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Enrollment

Interventions

Lidocaine 2% (preservative-free, without vasoconstrictor)DRUG

Using 25-27G sterile disposable needle, intramuscular injection of 2%preservative-free solution of lidocaine without vasocostrictor, 1.8 ml at the most painful trigger points with "Fast-in, fast out" or "peppering" method and inject the solution slowly.

Lidocaine 2% + Magnesium Sulfate 10% (combination)DRUG

Using 25-27G sterile disposable needle, intramuscular injection of 2%preservative-free solution of lidocaine without vasocostrictor mixed with 10%magnesium sulphate , Approx. 3.8 ml per point (1.8 ml Lidocaine + 2 ml MgSO₄) at the most painful trigger points with "Fast-in, fast out" or "peppering" method and inject the solution slowly.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Age between 18 and 70 years. 2. Clinical diagnosis of Myofascial Pain Dysfunction Syndrome (MPDS). 3. Presence of active myofascial trigger points in accessible muscles (e.g., masseter, temporalis, upper trapezius). 4. Pain duration ≥ 3 months. 5. Pain intensity ≥ 4 on the Visual Analog Scale (VAS). 6. Noprior trigger point injection in the affected area within the past 3 months. 7. Ability and willingness to provide informed consent. 8. Compliance with study visits and procedures Exclusion Criteria: 1. Known allergy or hypersensitivity to Lidocaine, Magnesium Sulfate, or related agents. 2. Current use of anticoagulants or history of bleeding disorders. 3. Systemic or local infection at or near the injection site. 4. History of fibromyalgia, central pain syndromes, or cancer-related pain. 5. Major psychiatric illnesses (e.g., schizophrenia, severe depression). 6. Recent surgery or trauma to the head, neck, or upper back (\<6 months). 7. Use of analgesics (NSAIDs, opioids) within 5 days before intervention. 8. Severe systemic diseases:- Uncontrolled diabetes mellitus- Liver or kidney failure- Severe cardiovascular conditions.

Outcomes

Primary Outcomes

Pain reduction.

Pain intensity will be assessed using the Visual Analogue Scale (VAS) ranging from 0 to 10 cm, where 0 indicates no pain and 10 indicates worst imaginable pain.

Time frame: Baseline, 1week, 2 weeks post-injection.

Muscle activity improvement.

Muscle activity will be assessed using surface electromyography (sEMG) by measuring Maximum Voluntary Contraction (MVC) in microvolts (µV). Higher values indicate improved muscle activity.

Time frame: Baseline, 1 week, 2 weeks post-injection

Secondary Outcomes

Pain experienced during injection

Pain during injection will be assessed immediately after injection using the Visual Analogue Scale (VAS) ranging from 0 to 10 cm, where 0 indicates no pain and 10 indicates worst imaginable pain.

Time frame: Immediately after injection