[Analgesic effect of intra-artcular fentanyl in knee arthroscopy to treat patellofemoral lateral hyperpressure syndrome].

INTRODUCTION: During arthroscopy for the treatment of patellofemoral lateral hyper-pressure syndrome (LHS), intra-articular morphine or its derivatives (fentanyl) may reduce postoperative pain when combined with anesthetics. We therefore decided to determine whether adding fentanyl to epinephrine and bupivacaine produced an increased analgesia.

MATERIAL AND METHODS: We randomly distributed 40 patients into two groups. The experimental group (n=20) was given 0.5% bupivacaine (2 mg/kg), epinephrine (100 microg) and fentanyl (2.5 microg/kg). The control group (n=20) received 0.5% bupivacaine (2 mg/kg) and epinephrine (100 microg). Patients underwent chondroplasty and retinacular release, and we assessed pain, time of analgesia and postoperative range of motion at postoperative hours 6 and 24.

RESULTS: The age and the grade of patellofemoral chondromalacia (PFC) were similar in both groups (p > 0.05). No differences were found in pain and ranges of motion intraoperatively and at postoperative hours 6 and 24 (p > 0.05) between both groups. The postoperative analgesia time was similar (p > 0.05).

CONCLUSIONS: Adding intra-articular fentanyl to the combination of epinephrine plus bupivacaine did not decrease pain, and did not increase neither the analgesia time nor the range of motion in patients with LHS undergoing knee arthroscopy.