Carpal tunnel release can be a risk factor for trigger finger: National Health Insurance data analysis

Purpose We aimed to compare trigger finger (TF) development between patients with carpal tunnel syndrome (CTS) treated with carpal tunnel release (CTR) and those treated conservatively, using the National Health Insurance Services data of Korea. We also aimed to investigate risk factors for post-CTR TF development. Methods We selected CTS patients with or without CTR (3543 patients in each group) between 2002 and 2015. Sex, age, follow-up duration after CTS diagnosis, and comorbidities associated with TF-development were matched using propensity score. We compared the rates of TF diagnosis and subsequent TF operations between groups. Thereafter, we selected patients with CTS undergoing CTR, for whom minimum follow-up exceeded five years. We compared sex, age, height, weight, and comorbidities associated with TF risk factors between the TF-occurrence and non-TF-occurrence groups. Results On comparing CTR-treated patients with those treated conservatively for CTS, CTR-treated patients presented with significantly higher rates of TF diagnosis (12.2%) and TF operations (4.7%) than patients without CTR (6.2% and 1.2%, respectively). Among 433 TF-diagnosed patients and 166 TF-operated patients after CTR, most were identified < 5 years after CTR, with 379 diagnosed (87.5%) and 147 operated (88.5%) patients. A total of 240 patients presented with newly developed TF over a five year period. Patients with subsequent TF exhibited a higher female sex rate and shorter height. None of the variables was significant risk factors for TF development in logistic regression analysis. Conclusion We confirmed high incidences of post-CTR TF diagnosis and operations. TF develops most frequently in the first postoperative year.