Reconstructive strategies for partial sacrectomy defects based on surgical outcomes

Background: Partial sacrectomy creates heterogeneous defects amenable to a wide variety of reconstructive techniques. Important factors to guide the choice of reconstruction technique have not been elucidated. The purpose of this study was to determine what factors best guide selection of reconstructive techniques following partial sacrectomy to optimize outcomes. Methods: The authors conducted a 15-year retrospective review of all consecutive partial sacrectomy reconstructions performed at The University of Texas M. D. Anderson Cancer Center. They analyzed the relationship of patient, tumor, and treatment factors, including defect volume, to flap choice and surgical outcome. Defect volume was categorized as small (<400 cm³), moderate (400 to 2000 cm ³), or large (>2000 cm³). Results: Fifty patients underwent partial sacrectomy reconstruction: 25 (50 percent) gluteus-based, 13 (26 percent) vertical rectus abdominis musculocutaneous, four (8 percent) gluteal thigh, four (8 percent) paraspinous, and four (8 percent) other. The distribution of small, medium, and large defect volumes was 15 (30 percent), 25 (50 percent), and 10 (20 percent), respectively. Resection volume as a continuous variable (p = 0.023) and as a categorical variable (p = 0.016) was significantly associated with the type of reconstruction used. The overall complication rate was high (44 percent), but no factors, including flap choice, were significantly associated with complications. Defect volume was significantly correlated with time to tumor recurrence (Cox regression). The rates of wound-healing complications, however, were similar irrespective of defect volume. Conclusions: Resection volume was the major factor determining flap selection. Despite the worsening functional morbidity and oncologic prognosis associated with increased resection volumes, wound-related complications were similar among defect volume groups.