Efficacy of a single posterior intra-articular dexamethasone injection for the management of radicular pain in adults with chronic cervicobrachial neuralgia

The primary objective is to evaluate the efficacy of a single posterior intra-articular injection of dexamethasone on radicular pain at one month in adults with uncomplicated chronic cervicobrachial neuralgia resistant to first-line medical treatment. 5, 3.

Secondary objectives include:

• Evaluation of cervical pain at short-term (Day 15 and 1 month) and medium-term (2 and 3 months) intervals.
• Assessment of activity limitations specific to the cervical spine at 1 month and 3 months.
• Evaluation of quality of life at 1 month and 3 months.
• Monitoring of radicular pain at Day 15, 2 months, and 3 months.
• Assessment of safety regarding the injection procedure. 4.
• Evaluation of analgesic use at Day 15, 1 month, 2 months, and 3 months.

The sponsor did not provide information regarding the total number of participants. The study population consists of adult patients, including both males and females, aged between 18 and 64 years, diagnosed with uncomplicated chronic cervicobrachial neuralgia. Eligible participants must present with unilateral monoradicular symptoms due to uncarthrosis and a predominant radicular pain characterized by a Visual Analog Scale score of at least 40/100. Inclusion requires documented foraminal conflict via computed tomography or magnetic resonance imaging performed within the preceding 6 months. The population must have experienced symptoms for a duration of at least 3 months and demonstrated resistance to first-line medical treatment, specifically including analgesics and non-steroidal anti-inflammatory drugs or corticosteroids for a minimum of 7 consecutive days within the last 3 months. Exclusion criteria include the presence of biological inflammatory syndrome, thrombocytopenia, or coagulation disorders. Female participants of childbearing age must utilize reliable contraception and provide a negative pregnancy test on the day of the procedure.

This randomized pilot study is designed to evaluate the efficacy of a single posterior intra-articular injection of dexamethasone compared to a placebo consisting of NaCl 0.9% for the management of cervicobrachial neuralgia. The methodology involves a comparison of the test substance against a control to assess impact on radicular pain. Following a screening process to confirm eligibility, participants undergo the intervention. The study includes several follow-up assessments at 15 days, 1 month, 2 months, and 3 months to monitor secondary endpoints such as cervical pain, the Neck Disability Index, and quality of life. The primary endpoint is the assessment of radicular pain at the 1-month visit. Throughout the trial, the occurrence of adverse events and the use of analgesics are recorded. The total duration of participant involvement extends until the end-of-study visit at 3 months post-injection.

The experimental treatment consists of dexamethasone administered via a single intra-articular injection at a dosage of 4 mg. This intervention is intended for the management of cervicobrachial neuralgia.

The control group receives NaCl 0.9% as a placebo.

The primary efficacy endpoint is the assessment of radicular pain (RP) at 1 month post-injection. This parameter is measured using a self-administered numeric rating scale ranging from 0 to 100, evaluating the 48-hour period preceding the assessment in comparison to baseline.

Secondary efficacy parameters include:

• Cervical pain, evaluated via a self-administered numeric rating scale from 0 to 100 over the 48 hours preceding Day 15, 1 month, 2 months, and 3 months.
• The Neck Disability Index (NDI) score, a self-administered functional scale ranging from 0 to 50, collected at Month 1 and Month 3.
• Professional status, self-reported at Month 1 and Month 3.
• Quality of life, assessed using the self-administered EQ-5D-5L scale at Month 1 and Month 3.
• Radicular pain levels recorded at Day 15, Month 2, and Month 3.
• The use of analgesics, measured using a self-administered 4-level scale at Day 15, 1 month, 2 months, and 3 months post-injection.

Safety assessments involve monitoring the occurrence of adverse events (AEs) and serious adverse events (SAEs), including surgical interventions, at each visit.