Early fracture of the sacrum or pelvis: an unusual complication after multilevel instrumented lumbosacral fusion.

STUDY

DESIGN

A retrospective review of a series of cases with a complication of instrumented lumbosacral fusion.

OBJECTIVES

To present a previously undescribed complication, early sacral or pelvic stress fracture, after instrumented lumbosacral fusion and to identify the risk factors associated with this complication.

BACKGROUND

There are a number of well-described complications of instrumented lumbosacral fusion, including delayed stress fracture of the pelvis. Early sacral or pelvic stress fracture after instrumented lumbosacral fusion has not been previously reported, to the authors' knowledge.

METHODS

The authors present three cases of early stress fracture occurring at 2-4 weeks after surgery in patients who underwent instrumented multilevel lumbosacral fusions for degenerative lumbosacral disease.

RESULTS

Two patients had sacral fracture, which to the authors' knowledge, has not been previously reported. Risk factors included lumbosacral instrumentation and fusion, osteoporosis in elderly women, and iliac crest bone graft procurement. All patients were treated conservatively, with restricted ambulation and gradual return to activity.

CONCLUSION

This complication can cause significant morbidity and a delay in the patient's return to function. A better understanding of the related biomechanical forces and preoperative risk factors may identify patients at risk and may aid in surgical planning and in expectations of postoperative recovery.