gms | German Medical Science

Objective: To describe the outcome of non-surgical treatment, including an orthosis and/or hand therapy, for symptomatic thumb carpometacarpal (CMC-1) instability. Secondary, the objective was to evaluate the conversion rate to surgical treatment.

Materials and Methods: In this multicenter cohort study, patients treated with an orthosis and/or hand therapy for symptomatic CMC-1 instability between 2012 and 2017 were included.

Measures included pain (0-100, Visual Analog Scale, VAS) and hand function (0-100, Michigan Hand Questionnaire, MHQ) at 6 weeks and 3 months. All patients that converted to surgery with a mean follow-up of 2.9 years (range 8mo - 6.7 y) were recorded.

Treatment consisted of an orthosis, hand therapy, or a combination treatment.

Results: A total of 462 participants were included.

VAS scores for pain during last week, at rest and during physical load improved with mean differences at 3 months of 18 [95% Confidence interval: 12-23], 13 [7-19] and 20 [95% CI: 14-26] points respectively (p<0.001).

MHQ total score and the subscales activities of daily life, work performance and satisfaction improved with a mean difference of 8 [4-11], 9 [3-15], 9 [3-16] and 19 [13-25] respectively (p<0.001-0.003). No significant changes were found in the other subscales.

At 3 months, 82.2% of the participants would consider to undergo the same treatment again under similar circumstances.

After a mean follow-up of 2.9 years, 67 (14.5%) participants were surgically treated.

Conclusions: In this study, patients treated non-surgically for symptomatic CMC-1 instability showed clinically relevant improvements in pain and hand function. Furthermore, only 14.5% of all 462 patients was surgically treated after a mean follow-up of 2.9 years, indicating this non-surgical treatment is a successful initial treatment of choice.

Future studies should investigate the outcomes for different non-surgical treatments for CMC-1 instability.