Percutaneous Sacroplasty for Osteoporotic Sacral Insufficiency Fractures: a Prospective, Multicenter, Observational Pilot Study

Background Context: Sacral insufficiency fractures (SIFs) can cause low back pain in osteoporotic patients. Symptomatic improvement may require up to 12 months. Treatment includes limited weightbearing and bed rest, oral analgesics, and sacral corsets. Significant mortality and morbidity are associated with pelvic insufficiency fractures. Percutaneous injection of polymethylmethacrylate (PMMA) into the fractured ala, sacroplasty, is an alternative treatment for SIF patients. Under fluoroscopic control, 13-G bone trochars are inserted into the fractured ala while the patient is maintained under conscious sedation. Initial reports have documented safe and effective performance of sacroplasty. Yet, these uncontrolled findings do not allow any precision in estimating complication rates or expected outcome.

Purpose: Assess rates of complications and observe outcomes after sacroplasty in a medium-sized uncontrolled cohort of SIF patients.

Study Design/setting: A prospective observational cohort study of consecutive osteoporotic SIF patients.

Patient Sample: Consecutive, osteoporotic patients with symptomatic SIFs electing to enter the study.

Outcome Measures: Visual Analogue Scale (VAS) score, analgesic utilization, and patient satisfaction.

Methods: Baseline VAS rating, analgesic usage, and duration of symptoms were recorded. Subsequent VAS ratings were assessed within 30 minutes after the procedure, at 2-, 4-, 12-, 24-, and 52-week postprocedure. Analgesic usage and patient satisfaction were assessed at final follow-up. Each procedure was performed under light intravenous conscious sedation using fluoroscopy. Two bone trochars were inserted between the sacral foramen and sacroiliac joint through which 2 to 3 cc of PMMA were injected.

Results: Fifty-two patients, 40 females, were treated. The mean age was 75.9 years with a mean symptom duration of 34.5 days. All patients were available at each follow-up interval except one patient who died because of unrelated pulmonary disease before the 4-week follow-up. The mean VAS score at baseline was 8.1 and 3.4 within 30 minutes after the procedure, 2.5 at 2, 2.1 at 4, 1.7 at 12, 1.4 at 24, and 0.8 at 52 weeks. Improvement was statistically significant using a repeated measures single-factor analysis of variance. One case of transient S1 radiculitis occurred but resolved completely with one transforaminal epidural steroid injection.

Conclusions: Sacroplasty for SIF appears to be associated with rapid and sustained pain relief in most patients with few complications. More rigorous trials are warranted to provide definitive evidence of the safety and efficacy of sacroplasty for SIFs.