A Study To Evaluate Methods To Evaluate Back Pain

Time to "meaningful relief" defined as elapsed time from start of treatment until participant depressed the second stopwatch indicating "meaningful relief" (meaningful to participant). Participant consider censored if participant did not depress the stopwatch by end of 4-hour in-patient evaluation, or became a treatment failure (rescue or discontinuation) during the time prior to depressing the second stopwatch. Censoring was at time of dropout if participant withdrew for non-efficacy related reasons during the 4-hour in-patient portion of the study. CI calculated using method of Simon \& Lee.

TOTPAR 0-8 sum of pain relief from 0 through 8 hours, weighted by the time duration between the current timepoint and the previous timepoint. Pain relief rated hourly (from baseline) by the participant on a 6-point scale: 0=no relief, 1=a little relief, 2=less than half relief, 3=more than half relief, 4=a lot of relief, 5=complete relief. Total possible score 0 to 40; higher score indicated better relief.

Time weighted sum of change calculated as sum of change from baseline in back stiffness scores from 0 through 8 hours, weighted by time duration between current timepoint and previous timepoint. Based on hourly (from baseline) back stiffness assessment rating from 0 (no muscle stiffness) to 100 (most possible muscle stiffness). Sum of change derived by subtracting score at post-dosing time point from baseline score. Total possible score -800 to 800; higher positive value was indicative of greater improvement.

Time to treatment failure defined as time from dosing to the time of rescue medication within the scheduled duration of the study (8 hours); or for participants who withdrew from the study due to lack of efficacy without taking rescue medication, the time of the last assessment was considered the time to treatment failure; or if participant did not take rescue medication, or did not discontinue due to lack of efficacy, the time to treatment failure was considered censored at 8 hours (the scheduled duration of the study).

Pain relief rated hourly (from baseline) by the participant on a 6-point scale: 0=no relief, 1=a little relief, 2=less than half relief, 3=more than half relief, 4=a lot of relief, 5=complete relief.

Low back muscle stiffness rated hourly (from baseline) by the participant by placing a line on a visual analog scale (VAS) from 0 millimeters (mm) to 100 mm in length with 0=no muscle stiffness up to 100 (most possible stiffness).

Flexibility assessed using Paris Plinth table with maximum extension (as if performing a sit-up) of 20 degrees movement. Angle at Bsl and at 4 hours standardized to 100 for assessment of maximum angle (x degrees), x degrees minus 5, and x degrees plus 5. Flexibility score derived using standardized value and VAS score (participant rating of pain by marking level of pain on 100 mm line 0=no pain up to 100=worst pain). Final derived data for extension flexibility were average of the extension flexibility data on the combined score (range -66 to 552); higher value indicated greater improvement.

Flexibility assessed using Paris Plinth table with maximum side-to-side movement of plus or minus (+/-) 10 degrees for left, and right (L, R), movement. Angle at Bsl and 4 hours standardized to 100 for assessment of maximum angle (x degrees), x degrees - 5, and x degrees + 5. Flexibility score derived using standardized value and VAS score (participant rating of level of pain on 100 mm line 0=no pain to 100=worst pain). Final derived data for overall flexibility was the average of side-to-side (L, R) flexibility data on the combined score (range -81 to 264); higher value=greater improvement.

Flexibility assessed using Paris Plinth table with maximum rotation at waist of plus or minus (+/-) 30 degrees for left, and right (L, R), movement. Angle at Bsl and at 4 hours standardized to 100 for assessment of maximum angle (x degrees), x degrees - 5, and x degrees + 5. Flexibility score derived using standardized value and VAS score (participant rating of level of pain on 100 mm line 0=no pain up to 100=worst pain). Final derived data for overall flexibility were the average of rotation (L, R) flexibility data on combined score (range -80 to 155); higher value=greater improvement.

Participant placed in a prone position on Paris Plinth table which is moved at 1 degree per second to maximum movement of 20 degrees for extension (as if performing a sit-up) to the degree of movement at which participant perceives discomfort or pain. Higher score indicated greater improvement.

Participant placed in a prone position on Paris Plinth table which is moved at 1 degree per second to maximum movement +/- 10 degrees for left, and right, side-to-side movement to the degree of movement at which participant perceives discomfort or pain. Maximum flexion based on the average of the left and right side-to-side scores. Higher score indicated greater improvement.

Participant placed in a prone position on Paris Plinth table which is moved at 1 degree per second to maximum rotation at waist of +/- 30 degrees for left, and right, movement to the degree of movement at which participant perceives discomfort or pain. Maximum flexion based on the average of the left and right rotation scores. Higher score indicated greater improvement.

Flexibility assessed using Paris Plinth table with maximum extension of 20 degrees movement (as if performing a sit-up). When participant feels discomfort or pain, participant places a mark to rate discomfort/pain (maximum) on a VAS of 100 mm in length with 0=no discomfort/no pain up to 100=most discomfort/most pain. Movement decreased 5 degrees (minus) and discomfort rated on VAS. Movement increased 5 degrees (plus) beyond first point when pain was reported and discomfort/pain again rated on the VAS. Higher score indicated greater discomfort/pain.

Flexibility assessed using Paris Plinth table with maximum side-to-side movement of +/- 10 degrees for L, R movement. When participant feels discomfort or pain, participant places a mark to rate discomfort/pain (maximum) on a VAS of 100 mm in length with 0=no discomfort/no pain up to 100=most discomfort/most pain. Movement decreased 5 degrees (minus) and discomfort rated on VAS. Movement increased 5 degrees (plus) beyond first point when pain was reported and discomfort/pain again rated on the VAS. Analyses based on the average of L, R scores. Higher score indicated greater discomfort/pain.

Flexibility assessed using Paris Plinth table with maximum rotation at waist of +/- 30 degrees for L, R movement. When participant feels discomfort or pain, participant places a mark to rate discomfort/pain (maximum) on a VAS of 100 mm in length with 0=no discomfort/no pain up to 100=most discomfort/most pain. Movement decreased 5 degrees (minus) and discomfort rated on VAS. Movement increased 5 degrees (plus) beyond first point when pain was reported and discomfort/pain again rated on the VAS. Analyses based on the average of L, R scores. Higher score indicated greater discomfort/pain.

At hour 8, or at the time of rescue, if it occurred, participants performed a global assessment in their diary in response to the question: How would you rate the study treatment as a pain reliever? Very Poor=0, Poor=1, Fair=2, Good=3, Very Good=4, Excellent=5.