Surgical treatment of vertebral osteomyelitis with recombinant human bone morphogenetic protein-2.

STUDY DESIGN: A retrospective clinical study.

OBJECTIVE: To evaluate the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) as the primary graft material for the surgical treatment of vertebral osteomyelitis.

SUMMARY OF BACKGROUND DATA: The clinical and radiographic results using allograft, autograft, and vascularized bone flaps for the surgical treatment of osteomyelitis have been previously reported. Despite an expanding body of literature documenting the value of rhBMP-2 in spinal fusion, its application to the management of spinal infection has never before been analyzed.

METHODS: Twenty patients underwent surgical treatment of vertebral osteomyelitis using rhBMP-2 and were analyzed with a mean follow-up of 40 months (range, 24-53 months). All patients were treated with anterior column debridement and instrumented reconstruction. Four (20%) patients were treated with an anterior approach alone while the remaining 16 (80%) patients underwent circumferential spinal reconstruction. Clinical outcomes were assessed by Frankel grade and Odom criteria. Radiographic fusion was characterized based on thin-section computerized tomography (CT) analysis.

RESULTS: Pathogens responsible for infection included Staphylococcus aureus (11; 55%), S. epidermidis (6; 30%), Bacteroides (1; 5%), and polymicrobial species (1; 5%). Infected segments of the spinal column based on region were found to be: thoracic (1; 5%), thoracolumbar (5; 25%), lumbar (11; 55%), and lumbosacral (3; 15%). The mean number of anterior and posterior segments fused was 3.3 (range, 2-5) and 6.5 (range 2-16), respectively. Forty-five percent of the subjects underwent multilevel corpectomies and fusion. All patients demonstrated clinical and radiographic evidence of spinal fusion at the time of follow-up. Patients had stable (14 patients) or improved (6 patients) Frankel grades after surgery. Odom criteria at final follow-up were: excellent (3; 15%), good (12; 60%), fair (4; 20%), and poor (1; 5%). There was no case of persistent or recurrent infection requiring revision surgery.

CONCLUSION: rhBMP-2 is a valuable graft option for the surgical treatment of vertebral osteomyelitis. When dosed in the manner reported, very high rates of fusion are achievable as is eradication of infection.