Table 2 Surgical factor frequency

Number of levels

 One

39

(90.70)

 Two

4

(9.30)

Levels^a

 L3–L4

7

(14.89)

 L4–L5

40

(85.11)

Blood transfusions

 No

41

(95.35)

 Yes

2

(4.65)

Diagnosis^b

 DDD

43

(100)

 Spondylolisthesis

41

(95.35)

 Grade I

32

(78.05)

 Grade II

9

(21.95)

 Scoliosis

11

(25.58)

 Radiculopathy

43

(100)

 Reflex changes

13

(30.23)

 Stenosis

43

(100)

 Instability

41

(95.35)

 Osteophytes

8

(18.60)

 Decreased disc height

43

(100)

 Herniated nucleus pulposis

5

(11.63)

 Facet joint degenration

41

(95.35)

 Vacuum phenomenon

0

(0)

 Other (facet cyst)

4

(9.31)

Local bone volume

 <10 cc

8

(18.6)

 10+ cc

35

(81.4)

PEMF^c

 No

37

(86.05)

 Yes

6

(13.95)