The Graf stabilisation system: early results in 50 patients

Abstract

The results of the first 50 consecutive patients using the Graf stabilisation system are presented. The average age of the patients was 41 years; there were 32 women and 18 men in the group. All patients suffered from intractable symptomatic degenerative disc disease which could be localised to one or more levels. All patients gave a history of chronic back pain, but the mean period of severe disability was 24 months. The mean preoperative disability score (Oswestry questionnaire) was 59%. The average period of follow-up was 24 months (range 19-36 months). At the latest review, the mean disability score was 31%. The clinical results were classified as "excellent" or "good" in 72% of patients, "fair" in 10%, "the same" in 16% and "worse" in 2%. All but three patients felt that surgery was worthwhile. The results have not deteriorated over the period of follow-up.

Biomechanical evaluation of posterior lumbar dynamic stabilization: an in vitro comparison between Universal Clamp and Wallis systems

“…The first pedicle screw-based system was likely the Graf ligamentoplasty, which used knitted Dacron bands (INVISTA, Wichita, KS, USA) to lock the facet joints in extension and thus limit flexion [18,19]. Although positive short-term results were obtained in carefully selected young patients, long-term follow-up results were not encouraging [20,21]. The Dynesys (Zimmer, Winterthur, Switzerland) is a popular device using titanium alloy pedicle screws and polycarbonate urethane spacers that surround tensioned polyethylene terephtalate (PET) cords on each side in order to reduce facet joint loading [22].…”

Does Wallis implant reduce adjacent segment degeneration above lumbosacral instrumented fusion?

“…However, to solve the complication of ASD several flexible or even dynamic devices have been used with controversial results [17,43,50,52]. It has been proposed that non-fusion motion preservation surgery may prevent accelerated ASD because of the protective effects of continuing segmental motion.…”

“…Some of them (Graf, Dynesys) were secured to the spine by pedicle screw fixation systems [17], while other implants are secured in the interspinous space [38,48]. Although early results of pedicle-screw systems of flexible intervertebral stabilization have been encouraging [17] some longterm results have revealed possible drawbacks [18,54], including increased lumbar lordosis, stretching of the Dacron parts, and malpositioning and loosening of pedicle screws leading to increased re-operation rate.…”

“…Non-rigid, dynamic or flexible instrumentations for lumbar spine have been developed to reduce ASD [17,18,27]. These implants are either fixed in the pedicles, or secured between the spinous processes of adjacent vertebrae [38,48].…”

Outcome of the Graf ligamentoplasty procedure compared with anterior lumbar interbody fusion with the Hartshill horseshoe cage

“…There was no objective assessment of the patients [8]. Grevitt et al [10] reported on 50 consecutive patients with a minimum follow-up of 19 months, who had symptomatic degenerative disc disease. The pre-operative Oswestry score of 59% improved to 31%.…”