Ultrasound-guided percutaneous needle tenotomy using Tenex system for refractory lateral epicondylitis; short and long-term effectiveness and contributing factors.

ABSTRACT

BACKGROUND: Ultrasound-guided percutaneous needle tenotomy (USPNT) has been proposed as an alternative treatment to surgical intervention for lateral epicondylitis (LE). The Tenex system (Tenex Health Inc., Lake Forest, CA, USA) for USPNT is an ultrasonic device involving a needle which oscillates at high frequency to debride and aspirate diseased tendon under ultrasound image guidance. This investigation evaluates the efficacy of USPNT using the Tenex system for LE refractory to conservative management. We also seek to evaluate patient-specific factors which may correlate with treatment response. MATERIALS AND METHODS: PRTEE (Patient-Rated Tennis Elbow Evaluation) and DASH (Disabilities of the Arm, Shoulder, and Hand) questionnaires were completed before performing the Tenex USPNT for all consecutive patients over a course of 38 months (Feb 2015-Mar 2018). Patients were contacted for follow-up evaluations. Paired t test was used to evaluate significant changes in treatment response (p < 0.05). The univariate Tobit regression model was applied followed by multivariate Tobit model with forward selection algorithm. All models were adjusted by preoperative score and follow-up duration. RESULTS: A total of 37 patients (average age 51± 9 years, M/F15/22) with refractory LE were included (mean follow-up, 531 days; range, 65-1148 days). Tenex USPNT significantly improved PRTEE and DASH scores (p < 0.001). In some patients, this decrease persisted for up to 3 years after intervention. A significant association between treatment response and post-procedure physical therapy (PT) was present. Post-procedure PT contributes to 60, 68, 59, and 50% of reduction in PRTEE pain, function, total scores, and DASH score, respectively (p < 0.001). No tendon ruptures, post-procedural infections, or other complications were noted. CONCLUSION: USPNT with Tenex significantly improves symptoms and function in individuals with LE even with long-term follow-up for 3 years. Post-procedure PT is associated with improved treatment response and should be considered after USPNT.