Efficacy of the Aspen Spinous Process System in Anterior Lumbar Interbody Fusion (ALIF)

This is a multi-center, prospective randomized clinical study to evaluate the clinical outcome of subjects with degenerative disc disease (DDD) treated with ALIF and supplemental posterior fixation using ASPEN Spinous Process System compared to pedicle screw instrumentation.

• Device: Aspen Spinous Process System
  Aspen Spinous Process System is an interspinous process fixation device
• Device: Pedicle Screw Fixation
  Pedicle Screws are used for the fixation of the spine

• Experimental: Aspen Spinous Process System
  Intervention: Device: Aspen Spinous Process System
• Active Comparator: Pedicle Screw Fixation
  Intervention: Device: Pedicle Screw Fixation

Inclusion Criteria:

• Age between 18 and 75 years
• Scheduled for an elective single level ALIF with posterior fixation
• Diagnosis of primary symptomatic DDD confirmed with appropriate imaging studies and/or positive lumbar discography
• Oswestry Disability Index (ODI) v 2.1 score >30%
• Failed at least 6 weeks of conservative care (non-surgical)/clinical signs of neurological deterioration
• No contraindications for ASPEN spinous process system (at the discretion of the investigator)

Exclusion Criteria:

• Prior lumbar fusion surgery at any level (prior discectomy and/or laminectomy allowed)
• Spondylolisthesis grade 3 or more
• Lytic spondylolisthesis
• Incompetent or missing posterior arch at the affected level (e.g. laminectomy, pars defect)
• Currently requires laminectomy at level of surgery
• Facet joints at implant level are absent or fractured
• Post-traumatic vertebral body compromise or acute fracture at implant level
• Body mass Index (BMI) > 40
• Known allergy to titanium
• Osteoporosis: SCORE (Simple Calculated Osteoporosis Risk Estimation) will be used to screen subjects who require DEXA. Subjects with T-score < -2.5 will be excluded
• Paget's disease, osteomalacia, or any other metabolic bone disease
• Use of medications or any drug known to potentially interfere with bone/soft tissue healing (e.g. chronic systemic steroids)
• Planned use of Bone Morphogenetic Protein (BMP)
• Unlikely to comply with the follow-up evaluation schedule
• Subject has recent history (less than 3 years) of chemical substance dependency or significant psychosocial disturbance that may impact the outcome or study participation
• Participation in a clinical trial of another investigational drug or device within the past 30 days
• Systemic infection such as AIDS, HIV, and active hepatitis
• Active malignancy defined as history of invasive malignancy, except if the subject has received treatment and displayed no clinical signs and symptoms for at least five years
• Pregnant or planning to become pregnant during the length of study participation
• Involvement in active litigation related to back problems at the time of screening
• Direct involvement in the execution of this protocol