Volume 184 - Issue 11
Clinical outcomes after acute osteoporotic vertebral fractures
Authors: Terrence H Diamond, Carl Bryant, Lois Browne and William A Clark
Med J Aust 2006; 184 (11): 589-590. || doi: 10.5694/j.1326-5377.2006.tb00394.x
Published online: 5 June 2006
Published online: 5 June 2006
In reply: We thank Mallows for his constructive comments, and would like to reply as follows.
1. Intention-to-treat analysis is normally associated with randomised controlled trials (RCTs). Our study was not an RCT, as patients who refused vertebroplasty formed the comparison group.1 We used intention-to-treat analysis to indicate that all patients who were assessed as eligible for our study at the outset were enrolled and were all included in the results presented, irrespective of subsequent events (ie, whether they were completely compliant, had died or were lost to follow-up). We thought it was important to make clear that the study was prospective, that all patients entered into the study were represented in the outcomes, and that patients had not been selected on the basis of later events or results.
2. A description of the analgesic requirements of a subgroup of the patients in our study has been published.2 More than 90% of the vertebroplasty-treated cohort were either able to cease or reduce their analgesia dose by at least 50% within 24 hours after the procedure. Before the procedure, an intravenous injection of pethidine (50–100 mg) was the only parenteral analgesia given routinely and would not have affected the pain scores at 24 hours.
3. Pain scores at 6 weeks were statistically lower in the vertebroplasty-treated group compared with the control group. The clinical significance was not apparent, as measured by the changes in the Barthel indices. This indicator is only a crude assessment of patients’ wellbeing, and a more detailed questionnaire of activities of daily living may have shown a difference. Pain scores recorded at 24, 48, 72 and 96 hours after the procedure would have been more sensitive, so that the additional pain, without vertebroplasty, could have been calculated from the area under the pain curve; the more data points, the more accurate the curve.
4. We elected to report the results as means ± 1 SD instead of 95% CIs. We used SDs to be consistent with our previous publications and other reports in this field. We agree that we could have used 95% CIs.
5. Patients were referred to Sydney Imaging Group from the inpatients and outpatients departments of St George public and private hospitals. All patients were treated without any out-of-pocket patient expenses. Private hospital inpatients were billed according to standard Medicare fees and outpatients were bulk-billed, which was revenue neutral for the radiology practice.
References
- Diamond TH, Bryant C, Browne L, Clark WA. Clinical outcomes after acute osteoporotic vertebral fractures: a 2-year non-randomised trial comparing percutaneous vertebroplasty with conservative therapy. Med J Aust 2006; 184: 113-117.
- Diamond T, Champion B, Clark WA. Management of acute osteoporotic vertebral fractures: a nonrandomized trial comparing percutaneous vertebroplasty to conservative therapy. Am J Med 2003; 114: 257-265. 0_i1091766