Trigger Point Injections for Post-Mastectomy Pain Syndrome

Breast Cancer Clinical Trial

Official title:

Trigger Point Injections for Post-Mastectomy Pain Syndrome: A Double-Blind Randomized Controlled Trial With Intention-to-Treat Analysis

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT04267315
• Other study ID #: 1474/19
• Status: Active, not recruiting
• Phase: Phase 2
• Start date: January 3, 2020
• Est. completion date: February 15, 2024

Study information

• Verified date: October 2023
• Source: Instituto do Cancer do Estado de São Paulo
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Post-Mastectomy Pain Syndrome (PMPS) is a chronic pain that persists for more than three months after a surgical breast procedure. It has 11-70% incidence in patients that underwent a breast surgery. It consists of mixed pain, frequently associated with myofascial pain, an specific type of muscular pain. Trigger point injections (TPI) are classically used for the treatment of myofascial pain in other painful conditions. However, there are no controlled trials assessing the efficacy of TPI in the treatment of PMPS. The intervention objective is to assess the efficacy of TPI in patients with PMPS, when associated with a comprehensive rehabilitation program and pain management.

Description:

INTRODUCTION: Post-Mastectomy Pain Syndrome (PMPS) is a chronic pain that persists for more than three months after a surgical breast procedure. It has 11-70% incidence in patients that underwent a breast surgery. It consists of mixed pain, frequently associated with myofascial pain. Trigger point injections (TPI) are classically used for the treatment of myofascial pain in other etiologies. However, there are no controlled trials assessing the efficacy of TPI in the treatment of PMPS

OBJECTIVE: Assess the efficacy of TPI in patients with PMPS, when associated with a comprehensive rehabilitation program and pain management.

METHODS: Double-blind randomized controlled trial with intention-to-treat analysis. Both groups will undergo standard of care delivered by Physiatrist blinded to group allocation. Active group will undergo TPI with 1% lidocaine in each identified trigger-point, weekly, for three consecutive weeks. Control group will undergo subcutaneous saline injection superficial to the same trigger points, with the same frequency and number of sessions. Primary outcome is the mean difference between groups for pain levels, as assessed by Visual Numeric Scale (VNS), from baseline to 3 months after the procedure.

STATISTICAL ANALYSIS: Difference between groups at baseline, one and three months after injection, using Analysis of Covariance (ANCOVA) for the following outcomes: VNS; Presence of active trigger points, Pressure pain threshold (PPT); Short-Form McGill Pain Questionnaire (SF-MPQ); Neuropathic Pain Symptom Inventory (NPSI); Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH); Range of motion (ROM) of affected shoulder, for abduction and external rotation; adverse events; use of pain medication.

Total sample size is 120. Alpha=5%, power=80%.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 72
• Est. completion date: February 15, 2024
• Est. primary completion date: November 30, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Breast cancer patients.

• PMPS diagnosis, as per Wisotzky et col.

• Pain > 3 months over breast, chest wall or shoulder ipsilateral to surgery.

• Pain Visual analog Scale (VAS) =4.

• At least one active trigger point in the following muscles: pectoralis major, superior trapezius, serratus anterior, levator scapularis, latissimus dorsi, infraspinatus

Exclusion Criteria:

• Current radiation therapy or time since completion < 3months.

• Allergy to lidocaine or other local anesthetics

• Active infection over injection sites

• Unavailability to be at the hospital during study intervention.

Related Conditions & MeSH terms

• Breast Cancer
• Fibromyalgia
• Myofascial Pain Syndrome
• Myofascial Pain Syndromes
• Post-mastectomy Pain Syndrome
• Somatoform Disorders
• Syndrome
• Trigger Point Pain, Myofascial

Intervention

Procedure:
• Trigger point injection
1mL injections of 1% lidocaine in the muscles identified active trigger points at the day of intervention (pectoralis major, serratus anterior, levator scapulae, latissimus dorsi, infraspinatus).
• Subcutaneous saline injection
0.2mL subcutaneous saline injections superficial to the muscles identified with active trigger points at the day of intervention (pectoralis major, serratus anterior, levator scapulae, latissimus dorsi, infraspinatus).

Other:
• Comprehensive Rehabilitation program
Patients in both groups will undergo standard of care rehabilitation delivered by a Physiatrist, which may include Physical Therapy, Occupational Therapy, Exercise Physiologist, Rehabilitation Nurse, Psychologist, as per Physiatrist's prescription. Both the comprehensive rehabilitation program and pain medications will continue to be managed by participant's Physiatrist, who will be blinded to patient's allocation. The researchers will be responsible for TPI and for data collection.

Locations

Country	Name	City	State
Brazil	Hospital de Câncer de Barretos	Barretos	São Paulo
Brazil	Instituto do Câncer do Estado de São Paulo	São Paulo

Sponsors (2)

Lead Sponsor	Collaborator
Instituto do Cancer do Estado de São Paulo	Hospital de Câncer de Barretos

Country where clinical trial is conducted

Brazil, 

References & Publications (1)

Wisotzky E, Hanrahan N, Lione TP, Maltser S. Deconstructing Postmastectomy Syndrome: Implications for Physiatric Management. Phys Med Rehabil Clin N Am. 2017 Feb;28(1):153-169. doi: 10.1016/j.pmr.2016.09.003. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Visual Numeric Scale (VNS) for pain in 3 months	Mean difference of Pain between groups from baseline to 3 months(T3m), assessed by the Visual Numeric Scale (VNS, 0-10), in which higher scores represent higher pain intensity.	3 months
Primary	Trigger-points	Number of active trigger-points in the assessed muscles (latissimus dorsi, levator scapulae, trapezius superior, infraspinatus, pectoralis major, serratus anterior). Mean difference between groups.	1 month
Primary	Trigger-points	Number of active trigger-points in the assessed muscles (latissimus dorsi, levator scapulae, trapezius superior, infraspinatus, pectoralis major, serratus anterior). Mean difference between groups.	3 months
Primary	Pressure Pain Threshold (PPT)	Pressure Pain Threshold (PPT) at bilateral latissimus dorsi, levator scapulae, trapezius superior, infraspinatus, pectoralis major, serratus anterior. Difference from baseline	1 month
Primary	Pressure Pain Threshold	Pressure Pain Threshold (PPT) at bilateral latissimus dorsi, levator scapulae, trapezius superior, infraspinatus, pectoralis major, serratus anterior. Difference from baseline	3 months
Secondary	Visual Numeric Scale (VNS) for pain in 1 month	Mean difference of Pain between groups from baseline,assessed by the Visual Numeric Scale (VNS, 0-10), in which higher scores represent higher pain intensity.	1 month
Secondary	Short-Form McGill Pain Questionnaire (SF-MPQ) - total score, sensorial and affective scale	Short-Form McGill Pain Questionnaire - total score, sensorial and affective scale. Mean difference between groups from baseline. Higher values represent higher pain intensity	1 month
Secondary	Short-Form McGill Pain Questionnaire (SF-MPQ) - total score, sensorial and affective scale	Short-Form McGill Pain Questionnaire - total score, sensorial and affective scale. Mean difference between groups from baseline. Higher values represent higher pain intensity	3 months
Secondary	Neuropathic Pain Symptom Inventory (NPSI)	Neuropathic Pain Symptom Inventory . Mean difference between groups from baseline. Higher values represent more symptoms of neuropathic pain.	1 month.
Secondary	Neuropathic Pain Symptom Inventory (NPSI)	Neuropathic Pain Symptom Inventory . Mean difference between groups from baseline. Higher values represent more symptoms of neuropathic pain.	3 months
Secondary	Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH)	Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH). Mean difference between groups from baseline. Higher values represent lower functionality.	1 month
Secondary	Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH)	Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH). Mean difference between groups from baseline. Higher values represent lower functionality.	3 months
Secondary	Shoulder range of motion (ROM)	Range of motion (ROM) of affected shoulder, for abduction and external rotation. Mean difference between groups from baseline.	1 month
Secondary	Shoulder range of motion (ROM)	Range of motion (ROM) of affected shoulder, for abduction and external rotation. Mean difference between groups from baseline.	3 months
Secondary	Percentage of patients with at least 30% improvement of pain as per VNS scores (VNS30%)	Percentage of patients with at least 30% improvement of pain as per VAS scores (VAS30%). Mean difference between groups.	1 month
Secondary	Percentage of patients with at least 30% improvement of pain as per VNS scores (VNS30%)	Percentage of patients with at least 30% improvement of pain as per VAS scores (VAS30%). Mean difference between groups.	3 months
Secondary	Percentage of patients with at least 50% improvement of pain as per VNS scores (VNS50%)	Percentage of patients with at least 50% improvement of pain as per VAS scores (VAS30%). Mean difference between groups.	1 month
Secondary	Percentage of patients with at least 50% improvement of pain as per VNS scores (VNS50%)	Percentage of patients with at least 50% improvement of pain as per VAS scores (VAS30%). Mean difference between groups.	3 months
Secondary	Adverse events	Number of participants with adverse events. Mean difference between groups.	1 month
Secondary	Adverse events	Number of participants with adverse events. Mean difference between groups.	3 months
Secondary	Pain medication	Use of pain medication. Classified as "Increased", "Decreased", "Stable" or "Non-applicable" . Mean difference between groups.	1 months
Secondary	Pain medication	Use of pain medication. Classified as "Increased", "Decreased", "Stable" or "Non-applicable" . Mean difference between groups.	3 months