A Prospective Randomized Postmarket Clinical Study of the TRANSITION Stabilization System

Inclusion Criteria:

- Any of the following acute or chronic instabilities or deformities of the thoracic,
lumbar or sacral spine:

- degenerative spondylolisthesis with objective evidence of neurologic impairment,

- kyphosis, or

- pseudoarthrosis (failed previous fusion)

- Age 18 or older at the time of consent

- Able to understand and sign informed consent form

- Psychosocially, mentally and physically able to comply with protocol

- Able to meet the proposed follow-up schedule at 6 mo, 12 mo, and 24 mo

Exclusion Criteria:

- Prior fusion surgery or another spinal device implanted in the thoracic, lumbar or
sacral spine

- Requires treatment of more than two vertebral levels

- Lytic spondylolisthesis at the index level(s)

- Clinically compromised vertebral bodies at the affected level(s) due to current or
past trauma

- Sustained pathologic fractures of the spine or hip, including prior fracture or
trauma to vertebral structures at any thoracic, lumbar, or sacral level

- Morbid obesity defined as a body mass index > 40, or a weight more than 100 lbs over
ideal body weight

- Pregnant or interested in becoming pregnant within the next 2 years

- Active systemic or local infection

- Known allergy to device materials titanium, polycarbonate (PCU), polyethylene
terepthalate (PET), or hydroxyapatite (HA).

- Taking medications or any drug known to potentially interfere with bone/soft tissue
healing (e.g., steroids, excluding routine NSAIDs)

- Systemic disease including AIDS, HIV, Hepatitis C

- Has an active malignancy defined as a history of any invasive malignancy (except
non-melanoma skin cancer), unless he/she has been treated with curative intent and
there has been no clinical signs or symptoms of the malignancy for at least 5 years

- Neuromuscular disorders such as muscular dystrophy, spinal muscular atrophy,
amyotrophic lateral sclerosis, etc.

- Participation in an investigational device or drug clinical trials within 30 days of
surgery

- Acute mental illness or substance abuse

- Prisoners