Wallis Implant Appears Effective in Relieving Pain in Some Patients
Many people who have surgery to relieve pain from bulging (herniated) discs in the lower back end up having to have repeat surgery. One study estimated that as many as 14 percent of all patients who had a first time (primary) discectomy need more surgery.
Some repeat surgeries are done with hardware or devices that are meant to stabilize the spine in the hopes of keeping the discs from bulging or herniating again. The authors of this study investigated if one such device, the Wallis device, would reduce the need for repeat surgeries.
Researchers followed 37 patients (26 males) who underwent disc surgery with the Wallis implant. The patients ranged in age from 15 to 58 years, average age 36. The patients were followed up at weeks 3 and 6, and then again at 6 and 12 months. The Oswestry Disability Index (ODI) questionnaire, the Short Health Form survey (SF-36), and the Visual Analog Scale (VAS) for pain were used, among other tests, to evaluate the surgery's outcome.
The findings showed that all patients experienced a significant drop in leg pain (average of 8.2 down to 1.5 on the VAS). The average ODI scale dropped from 43 to 12.7 and back pain dropped from a VAS of 6.6 to 1.4. There were no major complications. Four patients did have a repeat disc herniation after the primary surgery and 1 patient after a revision surgery.
The authors discussed the other types of implants available and how they differed from the Wallis implant. The Wallis implant is considered to be conservative because it doesn't need any changes in the vertebrae to be inserted, unlike other implants. This makes it easier to remove the Wallis implant if needed.
In conclusion, the authors said that the Wallis implant was successful in relieving both leg and back pain.
Yizhar Floman et al. Failure of the Wallis Interspinous Implant to Lower the Incidence of Recurrent Lumbar Disc Herniations in Patients Undergoing Primary Disc Excision. In Journal of Spinal Disorders and Techniques. July 2007. Vol. 20. No. 5. Pp. 337-341.