Table 1.

Inclusion and exclusion criteria for lumbar arthroplasty

Inclusion	Exclusion
Adults between 18 and 60 years old (bone maturity).	DDD > 1 symptomatic vertebral level
Degenerative disc disease (DDD) between L1 and S1.	Vertebral end-plates smaller than 34.5 mm in the media-lateral plan and/or 27 mm in the antero-posterior plan.
DDD certified by:	Allergy to :
▪ Low back pain and/or leg pain (radiculopathy) and	▪ Titanium
	▪ Polyethylene
▪ CT scan, MRI, discography, radiology, myelography and/or flexion/extension radiographs with at least one of the following:	▪ Cobalt
	▪ Chrome
	▪ Molybdenum
- Instability ( ≥ 3 mm translation or ≥ 5° degrees);	Past vertebral surgery (thoracic or lumbar)   ▪ Fusion
- Loss of disc high > 2 mm	▪ Bilateral spinal or unilateral vertebral decompression where > 50 % of the facet was removed
- Thickness/scar of the annulus pulposus
- Herniated nucleus pulposus; or	▪ Facet fracture
- Vacuum phenomenon
Oswestry disability index ≥ 40 (20/50)	Trauma (past or present) to the vertebral end-plates.
VAS ≥ 40/100	Pregnancy
Failure to improve with a trial of nonsurgical management (physical therapy, medications and epidural injection).

CT computed tomography, MRI Magnetic resonance imaging, mm millimeter.