John Temple

Catastrophic Fat Embolism Following Augmentation of Pedicle Screws with Bone Cement

The treatment of spinal fractures in patients with osteoporosis can be challenging. Osteoporotic bone weakens the purchase of internal fixation devices, which may be required for stabilization. There have been few reports on the use of polymethylmethacrylate for the structural augmentation of pedicle-screw fixation1,2. Theoretical complications of screw augmentation include leakage of cement causing nerve root or spinal cord compression, infection, and osteolysis due to particulate wear debris leading to screw loosening and hardware failure. The fat-embolism syndrome is a well-described complication of long-bone fractures and orthopaedic procedures involving reaming of long bones; however, it has rarely been described in association with spinal procedures. We are aware of only three cases of fat embolism syndrome following spinal arthrodesis and are aware of no such no cases following screw augmentation3-5. We present the case of a patient with intraoperative fatal fat-embolism syndrome following augmentation of screw fixation during a revision posterior spinal arthrodesis. A sixty-one-year-old woman with diabetes presented with a several-week history of left-sided weakness, back pain, and night sweats. Radiographic evaluation revealed progressive collapse of the eighth thoracic vertebra. Magnetic resonance imaging revealed decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images. Blood cultures were positive for Streptococcus viridans . A diagnosis of vertebral osteomyelitis was made. The patient underwent corpectomy of the seventh and eighth thoracic vertebrae and anterior spinal arthrodesis with placement of a titanium cage filled with rib autograft, followed by a posterior arthrodesis from the sixth to the ninth thoracic vertebrae ( Fig. 1 ). The patient tolerated both of the procedures well, and no early postoperative complications occurred. Fig. 1: Initial radiograph made after corpectomy of the …