A-MAV™ Anterior Motion Segment Replacement

For this clinical trial, there is only one treatment group- patients receiving the A-MAV™
Anterior Motion Segment Replacement via an anterior surgical approach in the lumbar region of
the spine from L4-S1.

Inclusion Criteria:

- Has back and/or radicular pain with degeneration of the disc as confirmed by patient
history, physical examination, and radiographic studies with one or more of the
following factors:

- instability as defined by > 5° angulation

- osteophyte formation of facet joints or vertebral endplates

- decreased disc height, on average by >2mm, relative to the next adjacent
vertebral segment

- scarring/thickening of ligamentum flavum, annulus fibrosis, or facet joint
capsule

- herniated nucleus pulposus

- facet joint degeneration/changes

- vacuum phenomenon

- Has single-level symptomatic degenerative involvement from L4-S1 requiring surgical
treatment

- Has intact facet joints at the involved vertebral levels documented by CT and/or MRI

- Has preop Oswestry score≥30

- Has preop back pain score ≥8

- Age 18 to 70 yrs, inclusive and is skeletally mature

- Has not responded to non-operative treatment for 6 mos

- If child-bearing potential, patient is non-pregnant, non-nursing, and agrees not to
become pregnant for 1 yr after surgery

- Is willing and able to comply with the study plan and sign the Patient Informed
Consent Form

Exclusion Criteria:

- Has primary diagnosis of a spinal disorder other than DDD at involved level

- Had previous anterior lumbar spinal surgery at involved level

- Had previous posterior lumbar spinal fusion surgical procedure at involved level

- Had prior posterior lumbar surgery resulting in significant muscle/ligament morbidity,
not including facet saving techniques

- Requires surgical intervention at more than 1 lumbar level

- Has severe pathology of facet joints of involved vertebral bodies

- Has facet arthritis or any posterior element insufficiency

- Has spondylolisthesis

- Has mid-sagittal stenosis of <8mm, based on remaining canal diameter

- Has rotatory scoliosis at involved level

- Has lumbar scoliosis with >11° sagittal plane deformity

- Had previous trauma to L4, L5, or S1 levels in compression or burst

- Meets any of the following criteria: Previous diagnosis of osteoporosis, osteopenia,
or osteomalacia; postmenopausal Non-Black female over 60 yrs of age and weighs less
than 140 pounds; postmenopausal female that has sustained a non-traumatic hip, spine
or wrist fracture; male over age 60 that has sustained a non-traumatic hip or spine
fracture. If Yes to any of these, a DEXA scan is required. If level of BMD is -3.5 or
lower or -2.5 or lower with vertebral crush fracture, the patient is excluded

- Had previous lumbar spinal fusion at adjacent level

- Bone growth stimulator use in spine

- Has obesity defined by BMI greater than or equal to 40

- Has arachnoiditis

- Has a non-contained or extruded herniated nucleus pulposus with acute nerve root
compression

- Has condition that requires postop medications that interfere with bone metabolism,
such as chronic steroid use or prolonged use of non-steroidal anti-inflammatory drugs,
excluding routine perioperative, non-steroidal anti-inflammatory drugs. Does not
include low dose aspirin for prophylactic anticoagulation

- Has overt or active bacterial infection, either local or systemic and/or potential for
bacteremia

- Has presence or prior history of malignancy (except for basal cell carcinoma of skin)

- Has documented metal allergy, titanium alloy intolerance or cobalt-chrome-molybdenum
alloy

- Is mentally incompetent. If questionable, obtain psych consult

- Has a Waddell Signs of Inorganic Behavior score of 3 or greater

- Has chronic or acute renal and/or hepatic failure or prior history of renal and/or
hepatic parenchymal disease

- Is prisoner

- Is pregnant

- Is an alcohol and/or drug abuser as defined by currently undergoing treatment for
alcohol and/or drug abuse

- Has history of autoimmune disease

- Has received treatment with an investigational therapy within 30 days prior to
implantation surgery or treatment is planned during 24 months following the
implantation surgery

- Has history of any endocrine or metabolic disorder known to affect osteogenesis

- Has any disease that would preclude accurate clinical evaluation