Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physical Therapy (MPT)


Physical Therapy

First Advisor

Thomas Mohr


Arthroscopy; Knee; Morphine; Pain, Postoperative -- drug therapy


Postoperative pam IS common following knee arthroscopy and has been typically controlled with opioids, the most popular of which is morphine. Morphine has been traditionally administered by intramuscular, intravenous, or epidural injections. These methods of administering morphine have been very effective in producing prolonged analgesia; however, they have also produce negative central nervous system side effects.

Recent research has suggested administering morphine via intraarticular injections to provide postoperative analgesia without the central nervous system side effects. However, there is little evidence to suggest that this method is effective. Therefore, the purposes of this randomized, double-blinded study were to 1) investigate the effects of intraarticular injections of morphine on pain, 2) determine the minimal effective dose of morphine, and 3) determine the effect of morphine on the need for supplemental analgesia (pain pills).

Seventy-six subjects participated m the study and were randomly injected with 0.0 mg, .25 mg, .50 mg, .75 mg, or 1.00 mg of morphine. Pain was assessed at 1, 3, 6, and 24 hours postoperatively using a 100 mm visual analogue scale. Subject's requests for supplemental analgesia were also recorded.

The results of this study found that any time interval > 5 hours resulted in a significant decrease in pain. The results of this study, however, did not find intraarticular injections of morphine to significantly reduce pain, or the need for supplemental analgesia.