The effects of morphine on human articular cartilage of the knee: an in vitro study.

Abstract

The purpose of this study was to determine the metabolic, histologic, and ultrastructural effects of morphine and its combination with saline and bupivacaine on human articular cartilage. In vitro study. Nonfibrillated human articular cartilage was harvested and transferred into an experimental culture consisting of a control medium, saline, or a combination of morphine/saline or morphine/saline/bupivacaine for 12, 24, or 72 hours. Each sample was radiolabeled to assess proteoglycan synthesis. Histologic and ultrastructural effects were also examined. We found a significant, dose-related, transient decrease in 35SO4 incorporation in the morphine/saline samples at 12 hours, and in the saline only samples at 24 hours. We found no evidence of histologic or ultrastructural damage to the cartilage. Morphine and saline can both produce a transient decrease in 35SO4 incorporation that normalizes by 72 hours. This study does not suggest any contraindication to the use of intra-articular morphine as a postoperative analgesic.