Multiexpandable cage for minimally invasive posterior lumbar interbody fusion

Figures & data

Figure 1 Luna 3D^® (Benvenue Medical Inc., Santa Clara, CA, USA) lumbar interbody fusion cage.

Notes: Major steps of deployment include (from left to right): (A) initial deployment of top and bottom components in a curved trajectory from a cannula (top and bottom images), (B) completion of top and bottom component deployment in a circular configuration, (C) initial advancement of middle component between top and bottom components, (D) completion of Luna 3D cage deployment, and (E) bone graft injection into implant concavity.

Figure 2 Axial view of Luna 3D^® (Benvenue Medical Inc., Santa Clara, CA, USA) lumbar interbody fusion cage in situ – showing an ALIF cage-type footprint.

Abbreviation: ALIF, anterior lumbar interbody fusion.

Figure 3 Lateral (A) and anteroposterior (B) radiographic views of initial deployment, middle component deployment (C and D), and fully deployed Luna 3D^® (Benvenue Medical Inc., Santa Clara, CA, USA) lumbar interbody fusion cage (E and F).

Table 1 Baseline patient characteristics (n=32)

Variable	Value
Demographics
Age, yearsa	59±16
Male sex	63%
Diagnosis
Spinal stenosis	72%
Spondylosis	66%
Spondylolisthesis	56%
Herniated nucleus pulposus	44%
Degenerative disc disease	34%
Scoliosis	9%
Symptoms
Radiculopathy	69%
Neurological deficits	63%
Motor deficits	47%
Pain
Back and leg	84%
Back only	3%
Leg only	13%
Prior spine surgery
Any spine surgery	50%
Laminectomy	31%
Discectomy	9%
Fusion	28%

Note:

a Mean ± standard deviation.

Table 2 Operative data

Variable	Value
Surgical approach
Minimally invasive	17
Mini-open	2
Open	13
Single-level posterior procedure (TLIF or PLIF)	17
L5–S1	9
L4–L5	6
L3–L4	1
L2–L3	1
Multilevel procedure	15
TLIF with Luna 3D^® (Benvenue Medical Inc., Santa Clara, CA, USA) cage	1
TLIF with Luna 3D cage (one level), static cage additional level(s)	7
TLIF with Luna 3D cage (one level), LLIF with static cage additional level(s)	7
Number of levels with Luna 3D cage	35
L5–S1	21
L4–L5	11
L3–L4	2
L2–L3	1

Abbreviations: LLIF, lateral lumbar interbody fusion; PLIF, posterior lumbar interbody fusion; TLIF, transforaminal lumbar interbody fusion.

Table 3 Clinical outcomes at 3 months (n=32)

Variable	Value
Symptoms resolved
Radiculopathy	21/22
Neurologic deficit	16/20a
Motor deficits	12/15a
Pain reduction / function improvementb
Back pain – MCID	27/29 (93%)
Leg pain – MCID	27/29 (93%)
ODI – >12 points improved	13/18 (72%)
X-ray measure improvementsc, d
Disc height	4.5±2.5
Local disc angle	6.1±3.4
Foraminal height	5.6±3.7
Regional lumbar lordosis	1.6±3.7

Notes:

a Two additional patients were reported as “improving”;

b data not available for all patients;

c n=29 levels;

d mean ± standard deviation.

Abbreviations: MCID, minimal clinically important difference; ODI, Oswestry Disability Index.

Figure 4 Sagittal (A) and axial (B) MRI and sagittal CT (C) scans show grade I–II degenerative spondylolisthesis at L4–L5, total collapse of the disc, and severe spinal stenosis.

Abbreviations: CT, computed tomography; MRI, magnetic resonance imaging.

Figure 5 Radiographs showing preoperative grade I–II degenerative spondylolisthesis with total disc collapse at L4–5 (A) and stable construct with restoration of disc space 3 months after minimally invasive TLIF with Luna 3D^® (Benvenue Medical Inc., Santa Clara, CA, USA) cage (B). At 3 months, the patient is doing well clinically and reported complete resolution of low back and lower extremity pain.

Abbreviation: TLIF, transforaminal lumbar interbody fusion.