Heated lidocaine/tetracaine patch for treatment of patellar tendinopathy pain

INTRODUCTION The pain of patellar tendinopathy (PT) may be mediated by neuronal glutamate and sodium channels. Lidocaine and tetracaine block both of these channels. This study tested the self-heated lidocaine-tetracaine patch (HLT patch) in patients with PT confirmed by physical examination to determine if the HLT patch might relieve pain and improve function. METHODS Thirteen patients with PT pain of ≥14 days' duration and baseline average pain scores ≥4 (on a 0-10 scale) enrolled in and completed this prospective, single-center pilot study. Patients applied one HLT patch to the affected knee twice daily for 2-4 hours for a total of 14 days. Change in average pain intensity and interference (Victorian Institute of Sport Assessment [VISA]) scores from baseline to day 14 were assessed. No statistical inference testing was performed. RESULTS Average pain scores declined from 5.5 ± 1.3 (mean ± standard deviation) at baseline to 3.8 ± 2.5 on day 14. Similarly, VISA scores improved from 45.2 ± 14.4 at baseline to 54.3 ± 24.5 on day 14. A clinically important reduction in pain score (≥30%) was demonstrated by 54% of patients. CONCLUSION The results of this pilot study suggest that topical treatment that targets neuronal sodium and glutamate channels may be useful in the treatment of PT.