Table 2.

Patient demographics

Demographics	Prior surgery group (n = 15) Mean value (SD)	Non-prior surgery group (n = 23) Mean value (SD)	P-value
Age at surgery	43.1 years (10.6)	45.6 years (11.9)	0.52
Gender (M vs. F)	10/5	12/11	0.51
BMI	25.4 (3.5)	23.8 (2.7)	0.11
Level of surgery (1 vs. 2)	11/4	11/12	0.29
Depression	6	10	0.74
Smoking past history	10	11	0.33
Litigation involvementa	6	6	1.0

^aPatients who were involved with either the workers compensation or personal injury systems