Evaluation of spinal fusion using autologous anterior strut grafts and posterior instrumentation for thoracic/thoracolumbar kyphosis

Abstract

Study design: A retrospective cohort study.

Objective: To evaluate anterior strut grafts in spinal fusion for thoracic/thoracolumbar kyphosis.

Summary and background data: Autologous strut grafts harvested from the fibula, iliac crest, and rib are frequently used for treating severe kyphosis and kyphoscoliosis. However, a majority of the studies have presented mixed patient populations kyphosis and/or scoliosis, treated either with anterior or anteroposterior fusion. Very few reports have presented an evaluation of autologous strut grafts for anterior fusion with posterior instrumentation for the treatment of kyphotic deformities.

Methods: A total of 23 patients comprised the study. Diagnosis was granulomatous infection (9 patients), congenital (6), posttraumatic (4), neurofibromatosis (1), ankylosing spondylitis (1), Scheuermann disease (1), and plasmacytoma of the vertebral body with pathologic fracture (1). Average age at surgery was 41 years (range 6-77). Indication for surgery was pain with or without progression in 15 patients and additional progressive neurologic deficit in the other 8. Anterior strut grafts consisted of the autologous fibula (9 patients), iliac (10), fibula and ribs (2), fibula and iliac (1), and fibula, iliac, and ribs (1). The fusion areas were thoracic (11 patients), thoracolumbar (11), and cervicothoracic (1). Anterior decompression was performed in 8 patients because of the presence of neurologic symptoms caused by cord compression. Dorsal fusion was performed in all patients with third-generation systems.

Results: Average 4.2 vertebrae were fused anteriorly. Mean follow-up bracing time was 9.7 months. Average kyphosis measured 50.9 degrees before surgery and 32.5 at a mean follow-up of 4.5 years (P < 0.0001). No graft breakages were noted at final follow-up. Solid fusion was achieved in all patients. No donor site complications were observed. Of the 8 patients presenting with neurologic deficits, 4 had full recovery, 3 had partial recoveries, and 1 had no improvement. Loss of postoperative correction > 5 degrees was observed in 3 patients. At final follow-up, 3 patients complained of occasional pain, and 1 complained of pain when lying on the back, particularly on hard surfaces.

Conclusion: Adequate correction was maintained throughout an average follow-up of 4.5 years, and solid fusion was obtained in all patients. Anterior strut grafts, supplemented with posterior fusion with instrumentation provide a good treatment alternative for the treatment of kyphosis deformity of the spine as a result of various etiologies.