A Comparison of Scar Infiltration, Scar Deactivation, and Standard of Care for the Treatment of Chronic, Post-Surgical Pain After Cesarean Section

Jennifer Loomis

Status: Completed

Conditions: Cesarean Section; Dehiscence; Scar

Treatments: Other: Physical therapy; Other: Scar Infiltration with 0.25-1% Lidocaine; Other: Scar Deactivation Surface Release Technique protocol

Study type: Interventional

Funder types: Other U.S. Federal agency

Identifiers

NCT03936309

FWH20190005H

Details and patient eligibility

About

To compare scar infiltration with 0.5-1% Lidocaine at a dose of 3 mg/kg (max dose 300 mg) or scar deactivation with acupuncture surface release technique to determine which is more effective in reducing pain in adult patients with chronic, post-surgical pain related to the site of incision after low transverse Cesarean section compared to standard of care physical therapy with the McKenzie Method.

Full description

While there is not a clearly established and widely accepted pathophysiological cause to this post-operative pain, studies have estimated that between 7-33% of patients experience chronic peri-incisional pain after Cesarean section with Pfannenstiel incision - a type of abdominal surgical incision that allows access to the abdomen and the most common method for performing Cesarean sections today - defined as pain persisting beyond the period of expected healing, approximately 3 months.

Management of chronic peri-incisional pain after Cesarean section requires an extensive workup including laboratory testing (CBC, ESR, Urinalysis, STI testing) and imaging (transvaginal ultrasonography and abdominal CT) to rule out organic causes. Once a visceral etiology from postoperative pain has been excluded, there is not a well-established guideline dictating standard of care, however treatment can include analgesics such as Acetaminophen or Non-Steroidal Anti-inflammatory Drugs, and in refractory cases suggestive of neuropathic pain Tricyclic Antidepressants, Gabapentin, Pregabalin, and Serotonin-Norepinephrine Reuptake Inhibitors can be used. If medicinal therapy fails to manage symptoms, consultation for pain management specialists and/or surgical evaluation is often considered.

Scar deactivation is used as standard of care for treatment and resolution of scar associated pain in patients with a history of Cesarean section by medical acupuncturists, both abdominal and/or low back pain that began after the cesarean section. Scar infiltration with lidocaine has been used in numerous clinical settings, masquerading under different names. Referred to as Neural Therapy in Germany, the technique of injecting short-acting local anesthetic into the dermal subcutaneous junction of scar tissue has been widely applied; however there is limited readily available clinical trial evidence supporting its reported effectiveness. Theoretically, it is postulated that the anti-inflammatory effects of local anesthetics play a role in mitigating the autonomic nervous system disruption of interference fields caused by scar tissue. Local anesthetics promote anti-inflammatory activity through a variety of mechanisms including reversibly inhibiting leukocyte adhesion by interfering with the action of integrins and leukocyte adhesion molecule-1, limiting leukocyte migration, reversible inhibition of phagocytosis, inhibition of phospholipase A2, inhibition of prostaglandins, inhibition of thromboxane release, inhibition of leukotriene release, inhibition of histamine release, reduction in free radical formation, and inhibition of cytokine release. Additionally, Lidocaine injection is proposed to alleviate nerve entrapment within fascia through hydrodissection, a technique being effectively utilized in the management of carpal tunnel syndrome.

Scar deactivation is the technique of inserting acupuncture needles at a 30-45 degree angle into the superficial fascia to surround a scar. It is postulated that needle insertion into connective tissue produces analgesia through a multifaceted process encompassing the disruption and remodeling of extracellular matrix in loose connective tissue, alterations in gene expression affecting neurotransmitter levels, and cellular signaling pathways impacted in response to fibroblast and mast-cell involvement. In traditional Chinese medicine, injuries resulting in scar tissue formation are thought of as areas of blood and subsequently Qi stagnation. Disruptions in the flow of Qi at the point of scar tissue can result in abnormal skin sensations such as pain, itching, and numbness in addition to systemic effects. A case report has demonstrated effective pain relief in with an acupuncture protocol utilizing scar deactivation technique.

Enrollment: 60 patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

**Patients must be able to get care at Nellis Air Force Base or Scott AFB (a military installation) in order to participate in this study.**

Inclusion Criteria:

• Female DoD beneficiaries age 18 years or older
• 3 months or greater postpartum with abdominal and/or back pain starting after low transverse Cesarean section scar.
• If subject has had prior Scar Deactivation with Surface Release Technique for cesarean section scar they must have completed a washout period of 12 weeks or more.

Exclusion Criteria:

• Pregnant
• Prior Scar Deactivation with Surface Release Technique for cesarean section scar within the last 12 weeks.
• Ever had Prior Scar Infiltration with Lidocaine for cesarean section.
• Active cellulitis surrounding scar
• Revision of Cesarean section scar
• Vertical incision or emergent Cesarean section

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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60 participants in 3 patient groups

Scar Deactivation Surface Release

Experimental group

Description:

Alternating placement of Spring Ten (0.30x40 mm) acupuncture needles to surround scar left in place for a treatment duration of 20 minutes. Needles will be placed at intervals of 1cm to 1.5 cm and will surround the scar with a maximum of 20 needles per treatment.

Treatment:

Other: Scar Deactivation Surface Release Technique protocol

Scar Infiltration with 0.25-1% Lidocaine

Experimental group

Description:

Will consist of calculation of 3 mg/kg dose of 0.5-1% Lidocaine and a dermal followed by subcutaneous injection using 1.5 inch 25 G needle and syringe appropriate for volume based on calculated dose.

Treatment:

Other: Scar Infiltration with 0.25-1% Lidocaine

Physical Therapy

Experimental group

Description:

Will be a referral to physical therapy specifying McKenzie protocol treatment for the presenting complaint. The McKenzie protocol is a form of standard of care physical therapy in which the physical therapist tries to find a cause and effect relationship between the positions the patient usually assumes while sitting, standing, or moving, and the location of pain because of those positions or activities. The therapeutic approach requires a patient to move through a series of activities and test movement to gauge the patient's pain response. The approach then uses that information to develop an exercise program designed to centralize or alleviate the pain.

Treatment:

Other: Physical therapy