Condition of Approval Study (COAST)

Treatment of Lumbar Spinal Stenosis With X-STOP® PEEK Spacer in Moderately Symptomatic Patients

This prospective, multicenter longitudinal five-year study of X-STOP PEEK usage in LSS patients is designed to supplement pre-market safety and effectiveness data with information on longer-term device performance in a population of patients with moderately impaired physical function at preoperative baseline (i.e., an "indicated" population) who elect to undergo X STOP PEEK surgery.

Study Overview

• Status: Terminated
• Conditions: Lumbar Spinal Stenosis
• Intervention / Treatment: Device: X-STOP PEEK

Detailed Description

This prospective, multicenter longitudinal five-year study of X-STOP PEEK implant usage in LSS patients is designed to supplement pre-market safety and effectiveness data with information on longer-term device performance in a population of patients with moderately impaired physical function at preoperative baseline (i.e., an "indicated" population) who elect to undergo X-STOP PEEK surgery. This post-approval study will enroll 240 patients at up to 8 clinical sites where all participating spine surgeons have completed a company-sponsored physician training program. The clinical sites recruited to participate in this study comprise a geographically diverse mix of academic, referral, and/or community based sites.

Safety and effectiveness data will be assessed at baseline and annually through five (5) years postoperatively. Office visits will be scheduled preoperatively, and at 6 weeks, 1, 2, 3, 4, and 5 years postoperatively. Clinical/neurological and radiographic examination will be performed during each office visit. A baseline patient history (including medication usage) will be taken, and concomitant medications will be recorded at each postoperative follow-up visit. In addition, patients will be asked to complete the following questionnaires prior to consultation with their physicians or their staff: Zurich Claudication Questionnaire (ZCQ), Oswestry Disability Index (ODI), Numeric Rating Scale (NRS), and SF-36 Health Survey. At the 2-, 3-, 4- and 5-year office visit, patients will also be asked two questions assessing the value of surgery and the overall improvement in the quality of life postoperatively.

The primary study endpoint in this study is treatment success. Secondary endpoints will include scores from the SF-36, ODI, and NRS, as well as incidence rates of adverse events, device failures, and secondary surgeries.

• Study Type: Interventional
• Enrollment (Actual): 176
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35249
      • The Kirklin Clinic - UAB Medical
  • Arizona
    • Tucson, Arizona, United States, 85712
      • Tucson Orthopaedic Institute-East Office
    • Tucson, Arizona, United States, 85741
      • Tucson Orthopaedic Institute-Northwest Office
  • California
    • Campbell, California, United States, 95008
      • Silicon Valley Spine Institute
    • Sacramento, California, United States, 95818
      • UC Davis Spine Center
    • Santa Monica, California, United States, 90404
      • UCLA Comprehensive Spine Center
  • Colorado
    • Denver, Colorado, United States, 80220
      • Colorado Neurosurgery Associates, P.C.
    • Golden, Colorado, United States, 80401
      • Panaorama Orthopedics and Spine Center
  • Connecticut
    • New Haven, Connecticut, United States, 06520
      • Yale School of Medicine, Dept. of Orthopaedics
  • District of Columbia
    • Washington, District of Columbia, United States, 20037
      • George Washington University Hospital Medical Facility Associates
  • Georgia
    • Marietta, Georgia, United States, 30060
      • Pinnacle Orthopedics
  • Illinois
    • Mount Vernon, Illinois, United States, 62864
      • Orthopaedic Center of Southern Illinois
  • Kentucky
    • Lexington, Kentucky, United States, 40536-0298
      • University of Kentucky, Dept of Neurosurgery
  • Louisiana
    • Shreveport, Louisiana, United States, 71101
      • Spine Institute of Louisiana
  • Missouri
    • Kansas City, Missouri, United States, 64116
      • Drisko, Fee & Parkins, P.C.
  • New York
    • East Syracuse, New York, United States, 13057
      • Upstate Orthopedics
  • Ohio
    • Cincinnati, Ohio, United States, 45219
      • Mayfield Clinic
  • Oregon
    • Bend, Oregon, United States, 97701
      • The Center Orthopedic & Neurosurgical Care & Research
    • Eugene, Oregon, United States, 97401
      • Neurospine Institute
  • Pennsylvania
    • Willow Grove, Pennsylvania, United States, 19090
      • OrthopaediCare
  • Texas
    • Plano, Denton, Mansfield, Texas, United States, 75093, 76208, 76063
      • Texas Back Institute
    • San Antonio, Texas, United States, 78258
      • Neurosurgical Associates of San Antonio
    • Temple, Texas, United States, 76508
      • Scott & White Memorial Hospital & Scott, Sherwood & Brindley Foundation

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 48 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. has a baseline score >2.0 in the Physical Function (PF) domain of the Zurich Claudication Questionnaire
2. is 50 years old or older
3. has leg/buttock/groin pain with or without back pain NOTE: Leg/buttock/groin pain must be completely relieved when flexed such as when sitting in a chair. If back pain is also present, it must be partially relieved when flexed.
4. can sit for 50 minutes without pain
5. can walk 50 feet or more
6. has a confirmed diagnosis of neurogenic intermittent claudication secondary to lumbar spinal stenosis, with X-Ray, MRI and/or CT evidence of thickened ligamentum flavum, narrowed lateral recess and/or central canal narrowing
7. has completed at least six months of conservative care therapy which may include but is not limited to physical therapy, bracing, systemic or injected medications
8. has signed a patient informed consent document
9. is physically and mentally willing and able or has a caregiver who can comply with the postoperative and routinely scheduled clinical and radiographic evaluations
10. lives in the immediate area and has no plans to relocate to another geographic area before completion of the study or lives outside the immediate area and will comply with the scheduled postoperative visits with a prearranged and designated physician

Exclusion Criteria:

1. has a baseline score less than or equal to 2.0 in the Physical Function (PF) domain of the Zurich Claudication Questionnaire
2. cannot sit for 50 minutes
3. cannot walk more than 50 feet
4. has unremitting pain in any spinal position
5. has axial back pain only without leg/buttock/groin pain
6. has a fixed motor deficit
7. has cauda equina syndrome defined as neural compression causing neurogenic bowel (rectal incontinence) or bladder (bladder retention or incontinence) dysfunction
8. has severe symptomatic lumbar spinal stenosis at more than two levels
9. has significant instability of the lumbar spine, e.g., isthmic spondylolisthesis or degenerative spondylolisthesis greater than grade 1 (on a scale of 1 to 4)
10. has an ankylosed segment at the affected level(s);
11. has significant scoliosis (Cobb angle is greater than 25 degrees)
12. has an acute fracture of the spinous process or pars interarticularis
13. has sustained pathologic fractures of the vertebrae or multiple fractures of the vertebrae and /or hips
14. has severe osteoporosis of the spine or hip, defined as bone mineral density (BMD) in the spine or hip more than 2.5 SD below the mean of adult normals in the presence of one or more fragility fractures
15. has Paget's disease at the involved segment(s) or metastasis to the vertebrae
16. has had any surgery of the lumbar spine
17. has significant peripheral neuropathy demonstrated by nerve conduction velocity tests
18. has acute denervation secondary to radiculopathy, as shown by EMG
19. has significant peripheral vascular disease characterized by diminished dorsalis pedus or tibial pulses
20. has extreme obesity as defined by a Body Mass Index (BMI) greater than 40 kg/m2
21. has an active systemic infection or infection localized to the site of implantation
22. has an active systemic disease such as AIDS, HIV, hepatitis, etc.
23. has a medical condition that may interfere with postoperative management and follow-up, or may result in patient death prior to study completion (e.g., Alzheimer's disease, unstable cardiac disease, active malignancy)
24. has a recent history of narcotic abuse (i.e., within last 3 years)
25. has a known allergy to titanium,titanium alloy, or polyetheretherketone
26. is immunologically suppressed, or has received or is receiving steroids at any dose daily for more than one month within the last 12 months
27. is currently involved in a study of another investigational product that may affect the outcome of this study
28. is pregnant or planning to become pregnant during the study period
29. cannot undergo MRI or tolerate closed MRI scanning.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: X-STOP PEEK; In this arm, patients will undergo X-STOP PEEK surgery.	Device: X-STOP PEEK; Placement of X-STOP PEEK in up to two levels in the lumbar spine for patients diagnosed with moderately symptomatic lumbar spinal stenosis in accordance with current labeling instructions for use.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Treatment Success Rate at 24 Months	Treatment success rate is reported as the percentage of participants who met all of the following criteria: Clinically significant improvement (by at least 0.5 points) in the Symptom Severity (SS) domain of the Zurich Claudication Questionnaire (ZCQ) compared to preoperative baseline; Clinically significant improvement (by at least 0.5 points) in the Physical Function (PF) domain of the ZCQ compared to pre-operative baseline; Patient satisfaction with treatment defined as a Patient Satisfaction (PS) score < 2.5; No additional surgery for lumbar stenosis performed; Maintenance of distraction; No dislodgement of the implant; No device-related complications	24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Treatment Success Rate at 60 Months	Treatment success rate is reported as the percentage of participants who met all of the following criteria: Clinically significant improvement (by at least 0.5 points) in the Symptom Severity (SS) domain of the ZCQ compared to preoperative baseline; Clinically significant improvement (by at least 0.5 points) in the Physical Function (PF) domain of the ZCQ compared to pre-operative baseline; Patient satisfaction with treatment defined as a Patient Satisfaction (PS) score < 2.5; No additional surgery for lumbar stenosis performed; Maintenance of distraction; No dislodgement of the implant; No device-related complications	60 months
Symptom Severity (SS) Scores Measured by Zurich Claudication Questionnaire (ZCQ)	ZCQ is a validated outcomes instrument specific to lumbar spinal stenosis, and captures data in 3 distinct domains: SS, PF, and post-treatment PS. SS Score is based on seven questions (overall pain, pain frequency, pain in the back, pain in the leg, numbness, weakness, and balanced disturbance) in ZCQ. The first 6 questions are scored 1 to 5. Balance disturbance is scored in a 1-3-5 scale. The SS score is the mean of all answered items in the questionnaire, ranging from 1 to 5. A lower score represents a better outcome/condition. If more than two items were missing, the SS score was considered as missing.	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Success Rate in Symptom Severity (SS) Domain of Zurich Claudication Questionnaire (ZCQ)	Success rate in SS domain of ZCQ is reported as percentage of participants who had success in SS domain of the ZCQ. The SS success was defined as clinically significant improvement by at least 0.5 point in SS score compared to preoperative baseline.	6 weeks, 12months, 24 months, 36 months, 48 months, and 60 months
Physical Function (PF) Scores Measured by Zurich Claudication Questionnaire (ZCQ)	PF score is the mean score of five physical function questions of ZCQ, ranging from 1 to 4. A lower score represents a better outcome/condition. If more than one item were missing, the PF score was considered as missing.	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Success Rate in Physical Function (PF) Domain of Zurich Claudication Questionnaire (ZCQ)	Success rate in PF domain of ZCQ is reported as percentage of participants who had success in PF domain of ZCQ. The PF success was defined as clinically significant improvement by at least 0.5 points in PF score compared to preoperative baseline.	6 weeks, 12months, 24 months, 36 months, 48 months, and 60 months
Patient Satisfaction (PS) Scores Measured by Zurich Claudication Questionnaire (ZCQ) at Post Treatment	PS score is the mean score of 6 questions of ZCQ, ranging from 1 to 4 if the number of responses exceeded four. A lower score represents a better outcome. Patients with PS score less than 2.5 at postoperative evaluation were considered positive, which implied that patients were satisfied with their treatment.	6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Success Rate in Patient Satisfaction (PS) Domain of Zurich Claudication Questionnaire (ZCQ) at Post Treatment	Success rate in PS domain of ZCQ at post treatment is reported as the percentage of participants who had success in PS domain of ZCQ. The PS success was defined as PS score less than 2.5.	6 weeks, 12months, 24 months, 36 months, 48 months, and 60 months
Oswestry Disability Index (ODI) Score	ODI Questionnaire was used to assess patient back function. The ODI score ranges from 0-100. The best score is 0 (no disability) and worst is 100 (maximum disability).	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
General Health Status -- SF-36 PCS	The Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) was used to assess general health status. The SF-36 results were summarized into two components, a physical component summary (PCS) and a mental component summary (MCS). The score for PCS is between 0 and 100, with higher scores denoting better quality of life.	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
General Health Status -- SF-36 MCS	MCS score is between 0 and 100, with higher scores denoting better quality of life.	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Back Pain in Numerical Rating Scales (NRS)	Back pain was measured using NRS. Patients rated their back pain on a scale from 0-10, with a score of 0 representing "no pain" and a score of 10 representing "pain as bad as it could be."	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Left Leg Pain in Numerical Rating Scales (NRS)	Left leg pain was measured using NRS. Patients rated their leg pain on a scale from 0-10, with a score of 0 representing "no pain" and a score of 10 representing "pain as bad as it could be."	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months
Right Leg Pain in Numerical Rating Scales (NRS)	Right leg pain was measured using NRS. Patients rated their leg pain on a scale from 0-10, with a score of 0 representing "no pain" and a score of 10 representing "pain as bad as it could be."	Baseline, 6 weeks, 12 months, 24 months, 36 months, 48 months, and 60 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent of Subjects With Pfirrmann Grades Increased From Baseline at Any Index Level at 24 Months	The Pfirrmann Grading System is descriptive and grades the status on an intervertebral disc as visualized with MRI using a 5-point system (grade I, II, III, IV or V). Grade I: disc is homogeneous with bright hyper-intense white signal intensity and normal disc height. Grade V: disc is inhomogeneous with hypo-intense black signal intensity and there is no more distinction between the nucleus and annulus, the disc space is collapsed. The percent of subjects with Pfirrmann grades increased from baseline at 24 months is reported.	24 months
Percent of Subjects With Pfirrmann Grades Increased From Baseline at Any Index Level at 60 Months	The Pfirrmann Grading System is descriptive and grades the status on an intervertebral disc as visualized with MRI using a 5-point system (grade I, II, III, IV or V). Grade I: disc is homogeneous with bright hyper-intense white signal intensity and normal disc height. Grade V: disc is inhomogeneous with hypo-intense black signal intensity and there is no more distinction between the nucleus and annulus, the disc space is collapsed. The percent of subjects with Pfirrmann grades increased from baseline at 60 months is reported.	60 months
Percent of Subjects With Pfirrmann Grades Increased at Adjacent Levels at 24 Months	The percent of subjects with Pfirrmann grades increased from baseline at adjacent levels at 24 months is reported.	24 months
Percent of Subjects With Pfirrmann Grades Increased at Adjacent Levels at 60 Months	The percent of subjects with Pfirrmann grades increased from baseline at adjacent levels at 60 months is reported.	60 months
Percent of Subjects Who Reported Implant-Related Adverse Events		Overall study period
Percent of Subjects Who Had Any Subsequent Lumbar Spine Surgery		Overall study period

Collaborators and Investigators

• Sponsor: Medtronic Spine LLC
• Investigators: Principal Investigator: Jim Malcolm, MD, Pinnacle Orthopedics

Publications and helpful links

General Publications

• Zucherman JF, Hsu KY, Hartjen CA, Mehalic TF, Implicito DA, Martin MJ, Johnson DR 2nd, Skidmore GA, Vessa PP, Dwyer JW, Puccio ST, Cauthen JC, Ozuna RM. A multicenter, prospective, randomized trial evaluating the X STOP interspinous process decompression system for the treatment of neurogenic intermittent claudication: two-year follow-up results. Spine (Phila Pa 1976). 2005 Jun 15;30(12):1351-8. doi: 10.1097/01.brs.0000166618.42749.d1.
• Hsu KY, Zucherman JF, Hartjen CA, Mehalic TF, Implicito DA, Martin MJ, Johnson DR 2nd, Skidmore GA, Vessa PP, Dwyer JW, Cauthen JC, Ozuna RM. Quality of life of lumbar stenosis-treated patients in whom the X STOP interspinous device was implanted. J Neurosurg Spine. 2006 Dec;5(6):500-7. doi: 10.3171/spi.2006.5.6.500.
• Kondrashov DG, Hannibal M, Hsu KY, Zucherman JF. Interspinous process decompression with the X-STOP device for lumbar spinal stenosis: a 4-year follow-up study. J Spinal Disord Tech. 2006 Jul;19(5):323-7. doi: 10.1097/01.bsd.0000211294.67508.3b.

Study record dates

Study Major Dates

• Study Start: August 1, 2007
• Primary Completion (Actual): February 1, 2015
• Study Completion (Actual): April 1, 2015

Study Registration Dates

• First Submitted: August 15, 2007
• First Submitted That Met QC Criteria: August 16, 2007
• First Posted (Estimate): August 17, 2007

Study Record Updates

• Last Update Posted (Actual): January 2, 2018
• Last Update Submitted That Met QC Criteria: December 6, 2017
• Last Verified: January 1, 2016

More Information

Terms related to this study

• Keywords: Lumbar Spinal Stenosis; Interspinous process decompression; X-STOP Spacer; Neurogenic Intermittent Claudication
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Pathological Conditions, Anatomical; Spinal Diseases; Bone Diseases; Constriction, Pathologic; Spinal Stenosis
• Other Study ID Numbers: LSS-006-COA