Analgesic control and functional outcome after knee arthroscopy: results of a randomized double-blinded trial comparing a hyaluronic acid supplement with bupivacaine.

Objective: Hyaluronic acid (HA) is a naturally occurring substance within normal synovial joints. Although its efficacy in treating osteoarthritis has been evaluated, it has not been established whether it is of benefit after routine arthroscopic procedures. We hypothesized that immediate supplementation with HA after completion of arthroscopy would result in improved short-term analgesic and functional outcomes after knee arthroscopy.

Design: Double-blinded randomized controlled trial.

Setting: Tertiary referral center.

Patients: One hundred ten patients presenting for routine arthroscopic procedures were invited to participate in the study. After exclusion criteria were applied, 98 patients were randomized to receive either 10 mL of 0.5% bupivacaine or 3 mL of HA into the joint immediately after completion of surgery.

Interventions: After completion of surgery, all patients were randomized to receive either 10 mL of 0.5% bupivacaine or 3 mL of HA into the knee joint.

Main Outcome Measures: Visual analogue scale (VAS) pain scores were obtained at baseline; 1, 2, and 24 hours; and 1, 2, and 6 weeks after surgery. Western Ontario and McMaster Universities (WOMAC) and Tegner-Lysholm scores were obtained at baseline and then at 1, 2, and 6 weeks after surgery.

Results: Forty-nine patients received intra-articular bupivacaine and 49 received HA. There was no statistical difference in any of the outcome measures (VAS pain scores, WOMAC, and Tegner-Lysholm) at any time point between the groups overall.

Conclusions: There was no benefit of HA injection immediately at the end of knee arthroscopy in the first 6 weeks after surgery.

Clinical Relevance: Routine use of HA at the time of knee arthroscopy cannot be recommended.