Cannabidiol Treatment Effective for Thumb Basal Joint Arthritis Pain, Disability

Treatment with a twice-daily application of topical cannabidiol (CBD) was associated with improvements in thumb basal joint arthritis-related pain and disability without adverse events (AEs), according to study results published in The Journal of Hand Surgery.

Researchers sought to explore the therapeutic potential of CBD for the treatment of pain associated with thumb basal joint arthritis. The phase 2, single-center, double-blind, randomized controlled study (ClinicalTrials.gov identifier: NCT04611347) was conducted among individuals recruited from a University of Virginia Hand Surgery Clinic.

A phase 1 skin test was initially performed in 10 healthy control participants, who were monitored for 1 week following twice-daily application of 1 mL of topical CBD (6.2 mg/mL) with shea butter. Because no AEs were identified, the researchers continued with a phase 2 trial, in which a total of 18 participants with symptomatic thumb basal joint arthritis were randomized to 2 weeks of twice-daily treatment with CBD (6.2 mg/mL) with shea butter or only shea butter. This was followed by a 1-week washout period, then a 2-week crossover period with the other treatment. Physical examination measurements and safety data were obtained at baseline and following completion of each treatment arm.

The mean participant age was 64.2 years. The mean Charlson Comorbidity Index score was 2.3 (range, 0 to 31, with a lower score predictive of increased 10-year survival). Among the 18 participants, 10 were nonsmokers, 5 were former smokers, and 3 were current smokers. Overall, 10 of the participants reported a history of thumb basal joint corticosteroid injections, although none had received an injection within 3 months prior to study enrollment.

No AEs were reported regarding mean heart rate, blood pressure, Columbia Suicide Severity Rating Scale scores, laboratory tests, skin changes, or patient-reported side effects. Treatment with CBD was associated with significant improvements in Visual Analog Scale (VAS) pain score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and Single Assessment Numeric Evaluation (SANE) scores from baseline compared with the control group (P <.05 for all).

The mean VAS pain scores (range, 0 to 10, with a lower score indicative of less pain) were 5 at baseline, 5 with the control cream (0% reduction), and 2 with the CBD cream (60% decrease; P <.05). The mean DASH scores (range, 0 to 100, with a lower score indicative of less disability) were 36 at baseline, 31 with the control cream (14% decrease), and 22 with the CBD cream (39% decrease; P =.05). The mean SANE scores (range, 0 to 100, with a higher score indicative of greater global well-being) were 67.5 at baseline, 67.5 with the control cream (0% increase), and 78.5 with the CBD cream (16% increase; P =.05).

Treatment with CBD was associated with an improvement in Patient-Reported Outcomes Measurement Information upper extremity scores (range, 0 to 100, with a higher score indicative of greater function), with scores of 39 at baseline, 38 with the control cream (3% decrease), and 42 with the CBD cream (8% increase). This difference, however, was not statistically significant. Similar parameters were reported in the groups with respect to range of motion, grip, and pinch strength.

A major limitation of the study included the fact that cointerventions used among the participants (ie, evaluation by a certified hand specialist, use of a thumb basal joint orthosis, and oral nonsteroidal anti-inflammatory drugs and/or acetaminophen, as needed) were potential confounding variables. Additional limitations included the small sample size and short duration of treatment.

The study authors concluded, “Larger, multicenter clinical trials are warranted to further investigate the safety, therapeutic potential, and dose-response of CBD for musculoskeletal pain.”

Disclosure: None of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies.  

Reference

Heineman JT, Forster GL, Stephens KL, Cottler PS, Timko MP, DeGeorge BR Jr. A randomized controlled trial of topical cannabidiol for the treatment of thumb basal joint arthritis. J Hand Surg Am. Published online May 27, 2022. doi:10.1016/j.jhsa.2022.03.002