Efficacy of common stabilization techniques on protecting the ulnar collateral ligament of the thumb: A cadaveric study

Introduction: The thumb ulnar collateral ligament is commonly injured, especially during sport, resulting in an acute injury that must be appropriately managed

Purpose of Study: To evaluate the effectiveness of common stabilization techniques for the thumb UCL in fresh cadaveric specimens and to analyze the anatomical differences between male and female UCLs.

Methods: Eight, fresh cadaveric specimens (79 ± 8 years old) were evaluated in four conditions; nostabilization, spica tape job, abduction tape job, and an over the counter spica orthosis. The forearm was stabilized, positioning the thumb in neutral. The thumb was attached to a Teflon rail-guided drop tower using an impact load transfer system designed to abduct the thumb with 131 Newton (N) of force. TEMA motion analysis software was used to calculate the maximum abduction angles at impact. Following biomechanical testing, an incision was performed along the ulnar aspect of the thumb to expose the UCL for measurement.

Conclusions: This is the first study to assess the efficacy of commonly used thumb stabilization methods. Bracing is often regarded as superior to taping, but these data suggest otherwise. This information may aid clinicians in understanding how to best protect the thumb UCL from sustaining initial injury and protection when returning to sport.

Results: All stabilization conditions significantly limited thumb abduction. The thumb abduction tape job was most effective (8.3°), followed by the spica tape job (15.8°), and the spica orthosis (16.6°). Each specimen was dissected following testing and no ligament damage was identified. No statistically significant difference was found between the length and width of male and female thumb UCLs.