. 2010 May 28;19(8):1262–1280. doi: 10.1007/s00586-010-1445-3

Table 1.

Prospective controlled studies

Study/author	Inclusion/exclusion criteria	Interventions/demografie	Follow up: duration and outcome
Sasso et al. [53] Randomized N = 76	Inclusion criteria: single-level symptomatic DDD at L1–S1 confirmed by radiology, more axial than radicular pain, VAS ≥ 40 and ODI ≥ 40, failed ≥ 6 mo of conservative treatment Exclusion criteria: previous bilateral or unilateral lumbar decompression, microdiscectomy, lumbar fusion, spondylolysis, isthmic spondylolisthesis, moderate to severe spinal stenosis, lumbar scoliosis, facet joint arthritic changes, significant motion segment instability, Paget disease, osteopenia (including osteoporosis or osteomalacia), metabolic bone disease	Index: TDR Type: FlexiCore^® Level: L5–S1 (n = 32) L4–L5 (n = 12) N = 44 ♀21 ♂23 (50 randomized) mean 36 years Control: anterior lumbar circumferential fusion Type: : femoral ring allograft, autogenous iliac crest bone, pedicle screw Level: L5–S1 (n = 17) L4–L5 (n = 5) L4–L5–S1 (n = 1) N = 23 ♀13 ♂10 (26 randomized) mean 41 years	Follow up I: 24 months (6 weeks, 3, 6, 12, 24 months), 75% lost to follow up C: 24 months (6 weeks, 3, 6, 12, 24 months), 70–35 lost to follow up Pain (VAS) I: pre-op.: 86, follow up: 16, difference: −70 C: pre-op.: 82, follow up: 20, difference: −62 Functional status (ODIv2.0) I: pre-op: 62%, follow up: 6%, difference −56% C: pre-op: 58%, follow up: 12%, difference −46% Complications I: n = 10 (22.7%), C: n = 10 (43.5%) Re-operations I: n = 5 (11.4%), C: n = 6 (26.1%)
Zigler et al. [52] Randomized N = 236	Inclusion criteria: single-level symptomatic DDD at L3–S1 confirmed by radiology, back and/or leg (radicular) pain, ODI ≥ 40 (20/50), failed ≥ 6 mo of conservative treatment Exclusion criteria: prior fusion surgery, current or prior fracture at L3–S1, osteoporosis, spondylolisthesis, facet joint disease or degeneration, spinal stenosis, back or leg pain of unknown etiology, Paget’s disease, osteomalacia, any other metabolic bone disease, allergy to device	Index: TDR Type: ProDisc^®-L Level: L5–S1 (n = 104) L4–L5 (= 54) L3–L4 (n = 3) N = 161 ♀79 ♂82 mean 38.7 years, SD 8.0 Control: anterior lumbar circumferential fusion Type: femoral ring allograft, autogenous iliac crest bone, pedicle screw Level: L5–S1 (n = 50) L4–L5 (n = 22) L3–L4 (n = 3) N = 75 ♀41 ♂34 mean 40.4 years, SD 7.6	Follow up I: 24 months (6 weeks, 3, 6, 12, 18, 24 months), 9.0% lost to follow up C: 24 months (6 weeks, 3, 6, 12, 18, 24 months), 11.5% lost to follow up Pain (VAS) P = 0.08 I: pre-op: 76, follow up: 37 (SD30.1), difference: −39 C: pre-op: 75, follow up: 43 (SD31.6), difference: −32 Functional status (ODI,chiropractor revised version), P = 0.0551 I: pre-op: 63.4% (SD12.6), follow up: 34.5% (SD24.8), difference −28.9% C: pre-op: 62.7% (SD10.3), follow up: 39.8% (SD24.3), difference −22.9% Clinical success (ODI improvement ≥ 25%) P = 0.0396 I: 69.1%, C: 54.9% Functional status (SF-36 improvement) P = 0.094 I: 79.2%, C: 70.0% Return to work P = 0.0485 I: pre-op: 83.5%, follow up: 92.4%, C: pre-op: 78.1%, follow up: 85.1% Patient Satisfaction (VAS) P = 0.015 I: 76.7 (SD 29.2), C: 67.3 (SD31.5) Surgery again? P = 0.1304 I: 81%, C: 69% Overall success, sponsor definition (10 endpoints) P = 0.0053* I: 63.5%, C: 45.1% Overall success, FDA definition (10 endpoints*) P = 0.0438* I: 53.4%, C: 40.8% Complications I: n = 10 (6.2%), C: n = 5 (6.7%) Re-operations I: n = 6 (3.7%), C: n = 4 (5.4%)
Blumenthal et al. [10] Randomized N = 304	Inclusion criteria: single level symptomatic DDD at L4–S1 confirmed by discography, back and/or leg pain without radiculopathy, VAS ≥ 40 and ODI ≥ 30, failed ≥ 6 mo of conservative treatment Exclusion criteria: Previous thoracic or lumbar fusion, current or prior, fracture at L4–S1, osteoporosis, spondylosis, spondylolisthesis > 3 mm, scoliotic deformity > 11°	Index: TDR Type: Charité^® Level: L4–L5 (n = 61) L5–S1 (n = 144) N = 205 ♀92 ♂113 mean 39.6 years (8.16), range 19–60 Control: anterior lumbar interbody fusion Type: BAK Level: L4–L5 (n = 32) L5–S1 (n = 67) N = 99 ♀55 ♂44 mean 39.6 years (9.07), range 20–60	Follow up I: 24 months, 8.5% lost to follow up C: 24 months 10.8% lost to follow up Pain (VAS) P = 0.1074 I: pre-op: 72.0, follow up: 31.2, difference: −40.6 C: pre-op: 71.8, follow up: 37.5, difference: −34.1 Functional status (ODIv1.0) P = 0.267 I: pre-op: 50.6%, follow up: 26.3%, difference −24.3%, C: pre-op: 52.1%, follow up: 30.5%, difference −21.6% Clinical success (ODI improvement ≥ 25%) P = 0.0038 I: 63.9%, C: 50.5% Return to work P = 0.6329 I: pre-op: 53.2%, follow up: 62.4%, difference 9.2%, C: pre-op: 57.6%, follow up: 65%, difference 7.4% Patient Satisfaction P = 0.0011 I: 73.7%, C: 53.1% Who would choose same treatment? P = 0.0062 I: 69.9%, C: 50.0% Overall success (4 criteria**) P < 0.0001ª* I: 57.1%, C: 46.5% Complications I: n = 56 (27.3%), C: n = 46 (46.5%) Re-operations I: n = 11 (5.4%), C: n = 9 (9.1%)
Guyer et al. [51] Randomized N = 233	Inclusion criteria: single level symptomatic DDD at L4–S1 confirmed by discography, back and/or leg pain without radiculopathy, VAS ≥ 40 and ODI ≥ 30, failed ≥ 6 mo of conservative treatment Exclusion criteria: Previous thoracic or lumbar fusion, current or prior, fracture at L4–S1, osteoporosis, spondylosis, spondylolisthesis > 3 mm, scoliotic deformity > 11°	Index: TDR Type: Charité^® Level: L4–L5 (n = 26) L5–S1 (n = 64) N = 90 ♀43 ♂47 mean 40.0 years (8.58), range 19–60 Control: anterior lumbar interbody fusion Type: BAK Level: L4–L5 (n = 10) L5–S1 (n = 33) N = 43 ♀19 ♂24 mean 38.8 years (8.69), range 25–55	Follow up I and C: 5 years, 43% lost to follow up Pain (VAS) P = NS I: pre-op.: 72.0, follow up: 30, difference: −42 C: pre-op.: 71.8, follow up: 30, difference: −41.8 Clinical success (ODI improvement ≥ 15 point) P = 0.8443 I: follow up: 68%, C: follow up: 65% Return to work P = 0.0403 I: 65.6%, C: 46.5% Overall success (4 criteria**) P = 0.0359ª* I: 57.8%, C: 51.2% Complications not mentioned Re-operations (2 to 5 years) I: n = 2 (2.2%), C: n = 0

Study/author

Inclusion/exclusion criteria

Interventions/demografie

Follow up: duration and outcome

Sasso et al. [53] Randomized

N = 76

Inclusion criteria:

single-level symptomatic DDD at L1–S1 confirmed by radiology, more axial than radicular pain, VAS ≥ 40 and ODI ≥ 40, failed ≥ 6 mo of conservative treatment

Exclusion criteria:

previous bilateral or unilateral lumbar decompression, microdiscectomy, lumbar fusion, spondylolysis, isthmic spondylolisthesis, moderate to severe spinal stenosis, lumbar scoliosis, facet joint arthritic changes, significant motion segment instability, Paget disease, osteopenia (including osteoporosis or osteomalacia), metabolic bone disease

Index: TDR

Type: FlexiCore^®

Level: L5–S1 (n = 32)

L4–L5 (n = 12)

N = 44 ♀21 ♂23 (50 randomized)

mean 36 years

Control: anterior lumbar circumferential fusion

Type: : femoral ring allograft, autogenous iliac crest

bone, pedicle screw

Level: L5–S1 (n = 17)

L4–L5 (n = 5)

L4–L5–S1 (n = 1)

N = 23 ♀13 ♂10 (26 randomized)

mean 41 years

Follow up

I: 24 months (6 weeks, 3, 6, 12, 24 months), 75% lost to follow up

C: 24 months (6 weeks, 3, 6, 12, 24 months), 70–35 lost to follow up

Pain (VAS)

I: pre-op.: 86, follow up: 16, difference: −70

C: pre-op.: 82, follow up: 20, difference: −62

Functional status (ODIv2.0)

I: pre-op: 62%, follow up: 6%, difference −56%

C: pre-op: 58%, follow up: 12%, difference −46%

Complications I: n = 10 (22.7%), C: n = 10 (43.5%)

Re-operations I: n = 5 (11.4%), C: n = 6 (26.1%)

Zigler et al. [52] Randomized

N = 236

Inclusion criteria:

single-level symptomatic DDD at L3–S1 confirmed by radiology, back and/or leg (radicular) pain, ODI ≥ 40 (20/50), failed ≥ 6 mo of conservative treatment

Exclusion criteria:

prior fusion surgery, current or prior fracture at L3–S1, osteoporosis, spondylolisthesis, facet joint disease or degeneration, spinal stenosis, back or leg pain of unknown etiology, Paget’s disease, osteomalacia, any other metabolic bone disease, allergy to device

Index: TDR

Type: ProDisc^®-L

Level: L5–S1 (n = 104)

L4–L5 (= 54)

L3–L4 (n = 3)

N = 161 ♀79 ♂82

mean 38.7 years, SD 8.0

Control: anterior lumbar circumferential fusion

Type: femoral ring allograft, autogenous iliac crest

bone, pedicle screw

Level: L5–S1 (n = 50)

L4–L5 (n = 22)

L3–L4 (n = 3)

N = 75 ♀41 ♂34

mean 40.4 years, SD 7.6

Follow up

I: 24 months (6 weeks, 3, 6, 12, 18, 24 months), 9.0% lost to follow up

C: 24 months (6 weeks, 3, 6, 12, 18, 24 months), 11.5% lost to follow up

Pain (VAS) P = 0.08

I: pre-op: 76, follow up: 37 (SD30.1), difference: −39

C: pre-op: 75, follow up: 43 (SD31.6), difference: −32

Functional status (ODI,chiropractor revised version), P = 0.0551

I: pre-op: 63.4% (SD12.6), follow up: 34.5% (SD24.8), difference −28.9%

C: pre-op: 62.7% (SD10.3), follow up: 39.8% (SD24.3), difference −22.9%

Clinical success (ODI improvement ≥ 25%) P = 0.0396

I: 69.1%, C: 54.9%

Functional status (SF-36 improvement) P = 0.094

I: 79.2%, C: 70.0%

Return to work P = 0.0485

I: pre-op: 83.5%, follow up: 92.4%, C: pre-op: 78.1%, follow up: 85.1%

Patient Satisfaction (VAS) P = 0.015

I: 76.7 (SD 29.2), C: 67.3 (SD31.5)

Surgery again? P = 0.1304

I: 81%, C: 69%

Overall success, sponsor definition (10 endpoints*) P = 0.0053

I: 63.5%, C: 45.1%

Overall success, FDA definition (10 endpoints**) P = 0.0438

I: 53.4%, C: 40.8%

Complications I: n = 10 (6.2%), C: n = 5 (6.7%)

Re-operations I: n = 6 (3.7%), C: n = 4 (5.4%)

Blumenthal et al. [10]

Randomized

N = 304

Inclusion criteria:

single level symptomatic DDD at L4–S1 confirmed by discography, back and/or leg pain without radiculopathy, VAS ≥ 40 and ODI ≥ 30, failed ≥ 6 mo of conservative treatment

Exclusion criteria:

Previous thoracic or lumbar fusion, current or prior, fracture at L4–S1, osteoporosis, spondylosis, spondylolisthesis > 3 mm, scoliotic deformity > 11°

Index: TDR

Type: Charité^®

Level: L4–L5 (n = 61)

L5–S1 (n = 144)

N = 205 ♀92 ♂113

mean 39.6 years (8.16), range 19–60

Control: anterior lumbar interbody fusion

Type: BAK

Level: L4–L5 (n = 32)

L5–S1 (n = 67)

N = 99 ♀55 ♂44

mean 39.6 years (9.07), range 20–60

Follow up I: 24 months, 8.5% lost to follow up

C: 24 months 10.8% lost to follow up

Pain (VAS) P = 0.1074

I: pre-op: 72.0, follow up: 31.2, difference: −40.6

C: pre-op: 71.8, follow up: 37.5, difference: −34.1

Functional status (ODIv1.0) P = 0.267

I: pre-op: 50.6%, follow up: 26.3%, difference −24.3%,

C: pre-op: 52.1%, follow up: 30.5%, difference −21.6%

Clinical success (ODI improvement ≥ 25%) P = 0.0038

I: 63.9%, C: 50.5%

Return to work P = 0.6329

I: pre-op: 53.2%, follow up: 62.4%, difference 9.2%,

C: pre-op: 57.6%, follow up: 65%, difference 7.4%

Patient Satisfaction P = 0.0011

I: 73.7%, C: 53.1%

Who would choose same treatment? P = 0.0062

I: 69.9%, C: 50.0%

Overall success (4 criteria***) P < 0.0001ª

I: 57.1%, C: 46.5%

Complications I: n = 56 (27.3%), C: n = 46 (46.5%)

Re-operations I: n = 11 (5.4%), C: n = 9 (9.1%)

Guyer et al. [51] Randomized

N = 233

Inclusion criteria:

single level symptomatic DDD at L4–S1 confirmed by discography, back and/or leg pain without radiculopathy, VAS ≥ 40 and ODI ≥ 30, failed ≥ 6 mo of conservative treatment

Exclusion criteria:

Previous thoracic or lumbar fusion, current or prior, fracture at L4–S1, osteoporosis, spondylosis, spondylolisthesis > 3 mm, scoliotic deformity > 11°

Index: TDR

Type: Charité^®

Level: L4–L5 (n = 26)

L5–S1 (n = 64)

N = 90 ♀43 ♂47

mean 40.0 years (8.58), range 19–60

Control: anterior lumbar interbody fusion

Type: BAK

Level: L4–L5 (n = 10)

L5–S1 (n = 33)

N = 43 ♀19 ♂24

mean 38.8 years (8.69), range 25–55

Follow up I and C: 5 years, 43% lost to follow up

Pain (VAS) P = NS

I: pre-op.: 72.0, follow up: 30, difference: −42

C: pre-op.: 71.8, follow up: 30, difference: −41.8

Clinical success (ODI improvement ≥ 15 point) P = 0.8443

I: follow up: 68%, C: follow up: 65%

Return to work P = 0.0403

I: 65.6%, C: 46.5%

Overall success (4 criteria***) P = 0.0359ª

I: 57.8%, C: 51.2%

Complications not mentioned

Re-operations (2 to 5 years) I: n = 2 (2.2%), C: n = 0

* 10 points for clinical success, sponsor definition: ≥ 15% improvement in ODI, device success, neurologic success, SF-36 improvement, six radiographic outcomes: no migration, no subsidence, no radiolucency, no loss of disc height, fusion status and ROM

** 10 points for clinical success, FDA definition: ≥ 15-point improvement in ODI, device success, neurologic success, SF-36 improvement, six radiographic outcomes: no migration, no subsidence, no radiolucency, no loss of disc height, fusion status and ROM

*** 4 criteria: ≥ 25% improvement in ODI, device failure, major complications, neurological deterioration

^aBlackwelder’s test of noninferiority

VAS (scale 0–100), ODI (scale 0–100), NS not specified