Conditions: Knee Osteoarthritis
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 40
Healthy volunteers: no

Brief summary:
Knee osteoarthritis (OA) can result in significant pain and limitation of function. A number of topical non-steroidal anti-inflammatory drugs have been shown to reduce pain in this condition. This study examines a different topical approach, utilizing a topical anesthetic agent, to evaluate if application of such an agent would provide relief of exercise-induced knee pain in people with knee OA.

Detailed description:
Subjects participated in two visits each at least 1 week apart, where they underwent two exercise interventions - a baseline exercise without treatment and a experimental exercise with intervention (Synera patch or Inactive patch). Participants rated their pain on a NRS-11 1 minute, 5 minutes, and 60 minutes after both exercises, as well as 6 hours after the experimental exercise, before bedtime, and the following morning. Subjects were randomized to receive either Synera at the first visit and the inactive patch at the second visit or the inactive patch at the first visit and Synera patch at the second visit.

Arms:
arm 1: lidocaine/tetracaine patch with heating component which consists of iron powder, activated carbon, sodium chloride, wood flour, water and filter paper. arm 2: placebo patch identical in appearance and composition (namely, the heating components) to the active patch other than lacking the lidocaine and tetracaine active ingredients.

Interventions: intervention 1: Synera intervention 2: Inactive patch
Intervention descriptions: intervention 1: 70 mg lidocaine/ 70 mg tetracaine topical patch applied once for 12 hours intervention 2: placebo patch applied once for 12 hours

Protocol document: