Multi-Center Prospective Study Evaluation Aspen Spinous Process Fixation System for Use in Posterolateral Fusion (PLF) in Patients With Spondylolisthesis

This study has been terminated.
(Will answer study question through other research means.)
Information provided by (Responsible Party):
Biomet, Inc. Identifier:
First received: March 15, 2012
Last updated: September 15, 2015
Last verified: September 2015
The purpose of this clinical investigation is to evaluate the clinical outcomes of subject with spondylolisthesis undergoing posterolateral fusion (PLF) surgery utilizing the Aspen™ Spinous Process Fixation System. The Aspen™ device will be evaluated using Oswestry Disability Index (ODI) improvement and success of fusion.

Condition Intervention Phase
Device: Aspen Spinous Process Fixation Device
Phase 4

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: A Multi-Center Prospective Study Evaluation Aspen Spinous Process Fixation System for Use in Posterolateral Fusion (PLF) in Patients With Spondylolisthesis

Further study details as provided by Biomet, Inc.:

Primary Outcome Measures:
  • Absolute change in Oswestry Disability Index (ODI) [ Time Frame: baseline to 12 months post-operative ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Title: Fusion success [ Time Frame: 12 Months post-operative ] [ Designated as safety issue: No ]
  • Change in Visual Analogue Scale (VAS) (pain) [ Time Frame: Baseline, 6 weeks, 2 weeks, 3 months, 6 months, 12 months, & 24 months ] [ Designated as safety issue: No ]
  • Neurological status [ Time Frame: Baseline, 6 weeks, 3 months, 6 months, 12 months, & 24 months ] [ Designated as safety issue: No ]
    motor functions, reflexes, and sensory

  • Operative parameters (estimate blood loss, surgery time, fluoroscopy time, and length of hospital stay) [ Time Frame: Surgical Visit ] [ Designated as safety issue: No ]
  • Pain medication usage [ Time Frame: Baseline, surgery, 6 weeks, 3 months, 6 months, 12 months, & 24 months ] [ Designated as safety issue: No ]
  • Change in EQ-5D-3L [ Time Frame: Baseline, 6 weeks, 3 months, 6 months, 12 months, & 24 months ] [ Designated as safety issue: No ]
  • Change in Zurich Claudication Questionnaire [ Time Frame: Baseline, 12 months & 24 months ] [ Designated as safety issue: No ]

Enrollment: 25
Study Start Date: February 2012
Study Completion Date: September 2015
Primary Completion Date: September 2015 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Aspen Spinous Process Fixation Device
The Aspen device provides supplemental posterior fixation for fusion
Device: Aspen Spinous Process Fixation Device
The Aspen device will be placed as posterior fixation to Posterolateral Fusion (PLF)


Ages Eligible for Study:   50 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients 50 years and older with spondylolisthesis requiring a single level posterolateral decompression and posterolateral fusion

Inclusion Criteria:

  • Age between 50 and older
  • Diagnosis of mild segmental instability on standing radiography lateral film defined as degenerative spondylolisthesis ≤ 4mm in dynamic imaging (i.e., flexion/extension)
  • Scheduled for an elective single-level posterior decompression and posterolateral fusion using AspenTM spinous process fixation system
  • Oswestry Disability Index (ODI) v 2.1 score >30%
  • Failed at least 3 months of conservative care (non-surgical) OR has clinical signs of neurological deterioration
  • Signed Informed Consent Form

Exclusion Criteria:


  • Marked degenerative spondylolisthesis (>4mm)
  • Lesions requiring surgery involving two levels
  • Prior surgery at index level or adjacent level
  • Prior spinal fusion surgery
  • Isthmic or lytic spondylolisthesis
  • Incompetent or missing posterior arch at the affected level (e.g. complete laminectomy, pars defect)
  • Requires complete laminectomy at level of surgery
  • Facet joints at implant level are absent or fractured
  • Vertebral body compromise or acute fracture at implant level
  • Body mass Index (BMI) ≥ 35
  • Known allergy to titanium
  • Osteoporosis: SCORE (Simple Calculated Osteoporosis Risk Estimation) will be used to screen subjects requiring 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 additional segmental fixation (eg. facet screws, anterior/lateral plating, anchored cages)
  • Use of Bone Morphogenetic Protein (BMP)*
  • Unlikely to comply with the follow-up evaluation schedule
  • In the opinion of the Investigator, Subject has history of chemical substance dependency or significant psychosocial disturbance that may impact the outcome or study participation
  • Active participation in a clinical trial of another drug or device
  • Active systemic infection or any other health condition that would preclude surgery
  • 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 study participation
  • Involvement in active litigation related to back problems at the time of screening
  • Direct involvement in the execution of this protocol
  • Pre-existing conditions that could interfere with the evaluation of outcome measures (e.g. musculoskeletal, neuromuscular, etc.)

Intra-operative Exclusion

  • Intra-operative visualization of a > 4mm spondylolisthesis not previously noted radiographically
  • Any change in the surgical procedure that violates the inclusion/exclusion criteria. (eg. switching to double level procedure; placing pedicle screws as posterior fixation).
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01560273

United States, Arizona
St. Joseph's Hospital and Medical Center
Phoenix, Arizona, United States
United States, California
Community Orthopedic Medical Group
Mission Viejo, California, United States
United States, Indiana
Goodman Campbell Brian and Spine
Indianapolis, Indiana, United States
United States, New York
Buffalo Spine Surgery
Lockport, New York, United States
United States, Oregon
Pacific Spine Specialists
Tualatin, Oregon, United States
Sponsors and Collaborators
Biomet, Inc.
Principal Investigator: Shah Goodman Campbell brain and Spine
  More Information

No publications provided

Responsible Party: Biomet, Inc. Identifier: NCT01560273     History of Changes
Other Study ID Numbers: ASP-11-002 
Study First Received: March 15, 2012
Last Updated: September 15, 2015
Health Authority: United States: Institutional Review Board

Additional relevant MeSH terms:
Bone Diseases
Musculoskeletal Diseases
Spinal Diseases
Spondylosis processed this record on February 08, 2016