Clinical Research Directory

Hyperbaric Oxygen Therapy in Complex Regional Pain Syndrome

The aim of the study is to investigate the efficacy of hyperbaric oxygen therapy as an adjunct in the management of severe complex regional pain syndrome.

CSS-SR Validation Study

Complex Regional Pain Syndrome (CRPS) is an orphan condition with no interventions proven effective in large-scale clinical trials. In-person clinical evaluations are required to make a CRPS diagnosis and determine study eligibility, making recruitment for CRPS trials challenging. To address this barrier, we will validate a self-report measure of CRPS symptom severity suitable for remote administration that was created by colleagues at Vanderbilt University. The aim of this study is to evaluate the correspondence at the item and total score level between the proposed self-report measure (CRPS Severity Score-Self Report; CSS-SR) and an existing validated measure of CRPS signs and symptoms derived from clinical history and physical examination data (CSS-Clinician version) and evaluate its diagnostic accuracy relative to clinically determined, criterion-based CRPS diagnosis using the Budapest criteria.

Low Dose Naltrexone Therapy for Complex Regional Pain Syndrome

Complex Regional Pain Syndrome (CRPS) is a rare and often debilitating chronic pain condition whereby individuals may experience extreme sensitivity, discoloration, and swelling of the affected area -- along with numerous other painful symptoms. There are currently a limited number of treatment options available to those suffering with the condition, with various treatments including nerve blocks, neuropathic medications, and desensitization physical therapy modules. There is budding interesting in the role naltrexone, an opiate antagonist, may play in the pain management of CRPS when prescribed in very low doses. This study aims to collect preliminary data on pain scores, symptom severity, and side-effects in patients with Complex Regional Pain Syndrome randomized to receive low dose naltrexone or placebo capsules. Enrollment of 40 patients total will occur over two years from study start to study end. Each patient will be randomized to receive placebo capsules or active low dose naltrexone capsules, with both the patient and treating clinician blind to the randomization. Each patient will be actively enrolled in the study for six months and will take the medication daily at the instructed dose for the respective duration of time. Following the initial visit and study enrollment, the investigators are asking each patient to return for three (3) in-person follow-up office visits. These office visits will occur 1 month after the patient starts the medication, 3 months afterwards, and 6 months afterwards. The final 6-month office visit will mark the conclusion of the patient's active participation in the study.

Complex Regional Pain Syndrome: Analgesic Outcome

This retrospective observational study aims to describe the use and analyze the effectiveness of various analgesic interventions in patients diagnosed with Complex Regional Pain Syndrome (CRPS) at the Pain Management Center of Hôpital Maisonneuve-Rosemont (HMR) between January 2020 and October 2025. Background: Complex Regional Pain Syndrome is a chronic pain condition characterized by severe, persistent pain accompanied by sensory, vasomotor, sudomotor, and motor/trophic changes, often following trauma or surgery. Despite established diagnostic criteria (Budapest criteria), its pathophysiology remains poorly understood, and evidence-based treatments are limited. While multidisciplinary functional rehabilitation remains the cornerstone of management, various analgesic interventions are used to facilitate recovery when medications fail to adequately control pain. Common interventions include: * Plexus or peripheral nerve blocks (brachial or sciatic, with or without adjuvants such as dexamethasone or dexmedetomidine) * Intravenous ketamine infusions * Sympathetic blocks (stellate or lumbar) * Intravenous pamidronate infusions Although all these techniques are used in clinical practice, their relative efficacy and predictive factors for success remain unknown. Clinicians rely on experience rather than data-driven guidance to select an initial intervention. Identifying factors such as CRPS subtype or symptom duration that predict analgesic response could improve treatment efficiency and functional recovery. Objectives: Primary objective: To determine the frequency distribution of first-line analgesic interventions used in patients with CRPS treated at HMR's Pain Management Center. Secondary objectives: * To evaluate the success rate ("significant analgesia") of each intervention when used first-line. * To assess the incidence of significant adverse effects. * To analyze success rates according to CRPS clinical subtype (vasomotor, sensory, florid, or indeterminate) and symptom duration (\<12 months, 12-18 months, \>18 months). * To determine the number of unsuccessful interventions required before achieving pain relief. Methods: This is a retrospective chart review including all adult patients with a CRPS diagnosis established using the Budapest criteria who received at least one eligible analgesic intervention during the study period. Data will be extracted from electronic medical records by the research team. Exclusion criteria include incomplete clinical documentation or missing information regarding the first consultation, intervention type, or analgesic outcome. Collected variables include demographics, medications, CNESST (workers' compensation) status, PTSD diagnosis, trauma type, CRPS characteristics (affected limb, type, subtype, symptom duration), details of the first intervention (technique, dose, use of adjuvants), analgesic response, and adverse effects.

Low-Dose Naltrexone for the Treatment of Complex Regional Pain Syndrome

The investigators are testing treatment with low-dose naltrexone (LDN) for symptom relief of complex regional pain syndrome (CRPS). Study participants will be randomly assigned to receive either LDN or placebo for a period of several weeks. During this period participants will be asked to attend either in-person or virtual study visits and complete questionnaires.

The Effects of Whirlpool and Contrast Bath in Patients with Complex Regional Pain Syndrome After Distal Radius Fracture

The aim of our study is to investigate the effects of whirlpool bath and contrast bath treatments on pain, disability, functionality and grip strength in patients with complex regional pain syndrome after distal radius fracture.

The Effects and Mechanisms of a High CBD Cannabis Extract (BRC-002) for the Treatment of Pain and Health in Complex Regional Pain Syndrome

The aim of this trial is to determine the potential effects and mechanisms of cannabinoid-induced pain relief in complex regional pain syndrome (CRPS). Multiple psychophysical approaches will be conducted in conjunction with psychological and inflammatory marker testing to determine if and how cannabinoids produce stabilized improvement in CRPS-related pain and comorbidities. The trial consisted of a pre-treatment screening period, six-week treatment period and a two-week follow-up.