Study designed to evaluate the efficacy and safety of Intranasal (IN) Morphine Nasal Spray (MNS075) 3.75 mg, 7.5 mg, 15 mg, and 30 mg, intravenous (IV) morphine 7.5 mg, or IN placebo in patients with moderate to severe post-surgical pain following orthopedic surgery. After initial dosing, up to six (6) doses of IN MNS075 7.5 mg or 15 mg for up to twenty-four (24) hours will be evaluated. The rescue dose remained the same for each.