European Spine Journal

, Volume 13, Issue 1, pp 22–31 | Cite as

A prospective randomized multi-center study for the treatment of lumbar spinal stenosis with the X STOP interspinous implant: 1-year results

  • J. F. ZuchermanEmail author
  • K. Y. Hsu
  • C. A. Hartjen
  • T. F. Mehalic
  • D. A. Implicito
  • M. J. Martin
  • D. R. JohnsonII
  • G. A. Skidmore
  • P. P. Vessa
  • J. W. Dwyer
  • S. Puccio
  • J. C. Cauthen
  • R. M. Ozuna
Original Article


Patients suffering from neurogenic intermittent claudication secondary to lumbar spinal stenosis have historically been limited to a choice between a decompressive laminectomy with or without fusion or a regimen of non-operative therapies. The X STOP Interspinous Process Distraction System (St. Francis Medical Technologies, Concord, Calif.), a new interspinous implant for patients whose symptoms are exacerbated in extension and relieved in flexion, has been available in Europe since June 2002. This study reports the results from a prospective, randomized trial of the X STOP conducted at nine centers in the U.S. Two hundred patients were enrolled in the study and 191 were treated; 100 received the X STOP and 91 received non-operative therapy (NON OP) as a control. The Zurich Claudication Questionnaire (ZCQ) was the primary outcomes measurement. Validated for lumbar spinal stenosis patients, the ZCQ measures physical function, symptom severity, and patient satisfaction. Patients completed the ZCQ upon enrollment and at follow-up periods of 6 weeks, 6 months, and 1 year. Using the ZCQ criteria, at 6 weeks the success rate was 52% for X STOP patients and 10% for NON OP patients. At 6 months, the success rates were 52 and 9%, respectively, and at 1 year, 59 and 12%. The results of this prospective study indicate that the X STOP offers a significant improvement over non-operative therapies at 1 year with a success rate comparable to published reports for decompressive laminectomy, but with considerably lower morbidity.


Lumbar spinal stenosis Surgical treatment Conservative treatment Randomized study Prospective study 



The authors thank the staff at each of the participating medical centers and St. Francis Medical Technologies for their support.


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • J. F. Zucherman
    • 1
    Email author
  • K. Y. Hsu
    • 1
  • C. A. Hartjen
    • 2
  • T. F. Mehalic
    • 3
  • D. A. Implicito
    • 4
  • M. J. Martin
    • 5
  • D. R. JohnsonII
    • 6
  • G. A. Skidmore
    • 7
  • P. P. Vessa
    • 4
  • J. W. Dwyer
    • 4
  • S. Puccio
    • 8
  • J. C. Cauthen
    • 9
  • R. M. Ozuna
    • 8
  1. 1.St. Mary’s Spine CenterSan FranciscoUSA
  2. 2.Greater Baltimore Medical CenterBaltimore
  3. 3.Maine Medical CenterPortland
  4. 4.Somerset Medical CenterSomerset
  5. 5.Tacoma General HospitalTacoma
  6. 6.East Cooper Medical CenterMount Pleasant
  7. 7.East Virginia Medical SchoolNorfolk
  8. 8.Brigham and Women’s HospitalBoston
  9. 9.North Florida Regional Medical CenterGainesville

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