A 24-month retrospective update: follow-up hospitalization charges and readmissions in US lumbar fusion surgeries using a cellular bone allograft (CBA) versus recombinant human bone morphogenetic protein-2 (rhBMP-2)

Table 1 24-month Follow-up Hospital Readmission Lengths of Stay

No. days	Full cohort			Single-level cohort
	Group		P value	Group		P value
	V-CBA (n = 1,522)	rhBMP-2 (n = 2,270)	P value	V-CBA (n = 1,076)	rhBMP-2 (n = 1,531)	P value
Unadjusted cumulative mean^a	8.16	7.15	0.0252*	8.16	7.07	0.1453
(SD)	(12.61)	(9.07)		(13.78)	(9.04)
Adjusted cumulative mean^b	7.71	7.45	0.4863	7.78	7.34	0.3595
(95% CI)	(7.15, 8.27)	(6.99, 7.15)		(7.08, 8.48)	(6.76, 7.91)

Readmission data did not include patients who may have received follow-up treatment outside of the Premier Healthcare System
^aWilcoxon rank-sum test
^bMultivariate regression models were adjusted with the following confounding factors identified in the original study: race, ethnicity, Charlson comorbidity index, health insurance status, initial admission type, initial admission source, initial discharge status, cage insertion, multiple levels treated (full cohort only), hospital size, hospital teaching status, hospital population served, and hospital region
*Statistically significant

ISSN: 1749-799X