TABLE II.
Primary End Point: Composite Clinical Success
| Arthroplasty (N = 113*) | Fusion (N = 47*) | P Value | |||
|---|---|---|---|---|---|
| Rate† | % | Rate† | % | ||
| Composite clinical success | |||||
| Yes | 83/113 | 73.5% | 12/47 | 25.5% | <0.001 |
| No‡ | 30/113 | 26.5% | 35/47 | 74.5% | <0.001 |
| Reoperation, lumbar injection, or stimulator implantation | 13/113 | 11.5% | 5/47 | 10.6% | 0.28 |
| Major device adverse event | 7/105 | 6.7% | 2/41 | 4.9% | 1.00 |
| ODI reduction < 15 points§ | 6/96 | 6.3% | 8/35 | 22.8% | 0.01 |
| Fusion failure# | 1/104 | 1.0% | 18/41 | 43.9% | <0.001 |
| New or progressive neurologic deficit | 3/107 | 2.8% | 5/44 | 11.4% | 0.047 |
The number of patients in each treatment group represents all patients who reached 24 months of postoperative follow-up (105 arthroplasty, 43 fusion) plus those patients who had early treatment failure (8 arthroplasty, 4 fusion), defined as failure in ≥1 measure of the composite clinical success criteria prior to 24 months.
Number of patients who met the criterion in the row/number of patients available to be evaluated for the criterion in the row.
Some patients failed to achieve the primary end point for >1 reason.
The end point was censored if the patient underwent reoperation or lumbar injection prior to outcome measurement.
Defined as lack of fusion at 24 months postoperatively in the fusion group or the presence of spontaneous/unintended fusion in the arthroplasty group. The outcome was censored in patients who underwent reoperation prior to fusion assessment.