Feasibility Study of Combined Peripheral Nerve Block and Physiotherapy for CRPS

Summary

Chronic pain is a debilitating condition affecting 1 in 5 Canadians with a yearly economic cost of over $40 billion in healthcare spending and loss of productivity. Since the prevalence of chronic pain is increasing, especially as the population ages, effective low-cost treatment is key to reduce the impact of chronic pain on patient quality of life and on healthcare costs. Due to the complexity of chronic pain and differences between the multitudes of pain conditions, developing effective treatments is challenging. This is especially true for Complex Regional Pain Syndrome (CRPS).

CRPS is characterized by severe pain out of proportion to tissue trauma, with local autonomic and inflammatory changes. The severity of pain from CRPS may result in an inability to work, depression, sleep disorders, or suicidal ideation.

Although its prevalence is low in Canada, CRPS is considered one the most debilitating and least understood pain conditions. As most current treatment options have low evidence of effectiveness, there is no definitive treatment available and most often, patients are struggling to maintain an acceptable quality of life. Thus, there is a pressing need to identify new and improved treatments for adults with CRPS.

An early hypothesis of CRPS pathophysiology posited that sympathetic nervous system over-activity led to many of the signs and symptoms of CRPS. As such, sympathetic nerve blocks, including stellate ganglion and lumbar sympathetic blocks, have been repeatedly investigated as a potential treatment of CRPS. However, a recent meta-analysis suggests that these blocks provided no benefits for those suffering with CRPS. Newer evidence suggests that a peripheral microvascular dysfunction may underlie CRPS pathophysiology. However, no clinical trials have investigated the efficacy of a treatment targeting this peripheral pathway.

The goal of this project is to assess the efficacy of a single-shot axillary approach to the brachial plexus block plus physiotherapy as a novel treatment protocol for CRPS. Our primary hypothesis is that providing a brachial plexus block in conjunction with a physiotherapy program would be superior to physiotherapy alone in treating pain and function in CRPS. Since this is a novel treatment protocol for CRPS, the purpose of our proposed study is to determine the feasibility of conducting a fully powered clinical trial.

Conditions

• Complex Regional Pain Syndromes

Interventions

PROCEDURE

Axillary Brachial Plexus Block plus Physiotherapy

Participants will receive a single-shot axillary-approach brachial plexus block. For the procedure, a 22g or larger peripheral intravenous cannula will be placed, and skin will be sterilized with chlorhexidine. Using aseptic technique, the anesthesiologist will anesthetize the skin and tract with 5cc of 1% lidocaine using a 25g 1.5" needle. After this, a 50mm 21g Pajunk needle will be guided under ultrasound with an in-plane technique to anesthetize the median, ulnar, radial, and musculocutaneous nerves. Identification of the axillary artery, vein and surrounding vessels will be done to ensure an intravascular injection is avoided. Once proper location is confirmed, the anesthesiologist will aspirate to ensure the needle is not intravascular. Once aspiration is confirmed negative, bupivacaine 0.25% 1.5mg/kg (lean body weight) will be injected in divided doses. 30 minutes after placement of the block, the standardized physiotherapy protocol will begin.

PROCEDURE

Physiotherapy alone

Participants in the EXP arm and the CON arm will complete the same physiotherapy program. PHYSIOTHERAPY PROTOCOL The physiotherapy program will include manipulation with or without a block. The goal of manipulation is to break up adhesions, possibly overcoming microvascular dysfunction. After the manipulation, participants will take part in a 6-week program which will include a weekly one-hour session with a physiotherapist at the KHSC-CPC and a home exercise program (HEP). During each session, the physiotherapist will work with the participants to increase ROM and limb function using manual therapy, stretching, and strengthening exercises specific to the affected joint(s) and most importantly using GMI. At the end of each session, the physiotherapist will prescribe exercises to complete at home.

Sponsors & Collaborators

• Tracy Cupido

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

110 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-02-01

Primary Completion

2025-09-01

Completion

2026-09-01

Countries

• Canada

Study Locations