Reoperation rates for symptomatic nonunions in posterior cervicothoracic fusions with and without bone morphogenetic protein in a cohort of 450 patients.
OBJECTIVE Fusions across the cervicothoracic junction have been challenging because of the large biomechanical forces exerted resulting in frequent reoperations for nonunions. The objective of this study was to investigate a retrospective cohort using chart review of posterior cervicothoracic spine fusions with and without bone morphogenetic protein (BMP) and to determine the reoperation rates for symptomatic nonunions in both groups. METHODS Between January 2009 and September 2013, posterior cervicothoracic spine fusion cases were identified from a large spine registry (Kaiser Permanente). Demographics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was used to estimate odds ratios and 95% confidence intervals. Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test. RESULTS In this cohort there were 450 patients (32.7% with BMP) with a median follow-up of 1.4 years (interquartile range [IQR] 0.5-2.7 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.088). In a subset of patients with more than 1 year of follow-up, 260 patients were identified (43.1% with BMP) with a median follow-up duration of 2.4 years (IQR 1.6-3.3 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervicothoracic fusions with and without BMP (0.0% vs 2.7%, respectively; p = 0.137) for more than 1 year of follow-up. CONCLUSIONS This study presents the largest series of patients using BMP in posterior cervicothoracic spine fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were 0% with BMP and 2.7% without BMP. No statistically significant difference in the reoperation rates for symptomatic nonunions with or without BMP was found.
Department of Neurosurgery, Kaiser Permanente Medical Group, Sacramento;
Kern H
KH
Guppy
Surgical Outcomes & Analysis Unit of Clinical Analysis, Kaiser Permanente, San Diego; and.
Jessica
J
Harris
Surgical Outcomes & Analysis Unit of Clinical Analysis, Kaiser Permanente, San Diego; and.
Jason
J
Chen
Surgical Outcomes & Analysis Unit of Clinical Analysis, Kaiser Permanente, San Diego; and.
Elizabeth W
EW
Paxton
Department of Orthopaedics, Kaiser Permanente Southern California, Baldwin Park, California.
Johannes A
JA
Bernbeck
D000368:Aged; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D002574:Cervical Vertebrae / Q000187:drug effects / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D065289:Pedicle Screws; D012042:Registries; D012086:Reoperation / Q000379:methods / Q000706:statistics & numerical data*; D013123:Spinal Fusion / Q000379:methods / Q000706:statistics & numerical data*; D013904:Thoracic Vertebrae / Q000187:drug effects / Q000601:surgery*; D014481:United States / Q000453:epidemiology
D019485:Bone Morphogenetic Proteins
ASA = American Society of Anesthesiologists; BMI = body mass index; BMP; BMP = bone morphogenetic protein; ICBG = iliac crest bone graft; ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification; IQR = interquartile range; LOS = length of stay; bone morphogenetic protein; cervical; nonunion; posterior cervicothoracic fusion; pseudarthrosis; reoperation; retrospective; spine registry