The purpose of this study is to demonstrate the non-inferiority of AttraX® Putty as a bone graft substitute for autograft in instrumented posterolateral fusion of the thoracolumbar spine, in terms of efficacy and safety.
Spinal fusion, a surgical procedure frequently used for many spinal conditions requiring stabilization of the vertebral column, is currently performed by using large amounts of autologous bone graft or autograft. A substitute for this patient own bone would eliminate the graft harvesting morbidity that is currently one of the main disadvantages. Recently, a promising synthetic graft substitute has been developed that has shown favorable results in pre-clinical studies. This product is AttraX® Putty (CE-557130), a bioresorbable tricalcium phosphate (TCP), mixed with a fast resorbing polymer carrier to improve surgical handling. The aim of the current study is to clinically investigate AttraX® Putty as an alternative to autologous bone graft in adult patients qualified for instrumented posterolateral fusion of the thoracolumbar spine (T10-S1). The study design is a patient and observer blinded, controlled, randomized, multi-center clinical trial with intra-patient comparisons. This means that each patient is it owns control. According to a randomization scheme, one side of the spine will be grafted with AttraX® Putty the other side receives bone harvest from the iliac crest, which is currently the gold standard. The primary outcomes of this study are the posterior spinal fusion rate after one year (based on CT-scans), and potential serious adverse events related with AttraX® Putty. Secondary outcomes are the resorption characteristics during the first year, volume of bridging bone mass after one year, evaluation of iliac crest pain, correlation of the posterior fusion rate to the presence of interbody fusion after one year and the posterior spinal fusion rate after two years.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
DOUBLE
Enrollment
100
Synthetic bone graft comprised of calcium phosphate granules and hydroxyapatite with an advanced biodissolvable polymer carrier that allows for better handling of the granules in putty form.
Corticocancellous bone harvested from the iliac crest, with our without local bone obtained from decompression and/or preparation for fusion (facetectomy and denudement).
Onze Lieve Vrouwe Gasthuis
Amsterdam, Netherlands
Rijnstate Hospital
Arnhem, Netherlands
Amphia Hospital
Breda, Netherlands
University Medical Center Utrecht
Utrecht, Netherlands
Posterior spinal fusion rate after one year
For the efficacy analysis of AttraX® Putty as a bone graft substitute for autograft in instrumented posterolateral fusion of the thoracolumbar spine, a comparison will be made between the fusion performance of the AttraX condition and the autograft condition after one year, assessed at CT-scans. Non-inferiority of AttraX® Putty will be tested with a McNemar's test.
Time frame: One year (12-15 months) after surgery
Rate of (serious) adverse events with a potential relation with AttraX® Putty
The safety of AttraX® Putty will be evaluated by documenting the number and nature of all (serious) adverse events that occur within the study population. The complication rate will be compared to the rate in control populations from the UMC Utrecht and a recently performed comparable multicenter-RCT coordinated by the UMC Utrecht. In addition, all (serious) adverse events will be evaluated for any potential relation with AttraX® Putty.
Time frame: Untill 2 years (24-27 months) after surgery
Resorption characteristics of AttraX® Putty compared to autograft during the first year
In a subset of the study population, additional DEXA-scans at 1-5 days after surgery (reference scan) and at 6 weeks, 3 months, 6 months and 1 year follow-up will be made to evaluate the resorption characteristics of AttraX® Putty compared to autograft in the instrumented fusion locations.
Time frame: During the first year (12-15 months) after surgery
Volume of bridging bone mass after one year
As quantification of the bone mass volume allows more detailed investigation of the amount of bone that has been formed, the volume of bridging bone mass derived from AttraX® Putty will be compared with the bone mass derived from autograft, using the one year CT scans made for the primary objective.
Time frame: One year (12-15 months) after surgery
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Visual analogue pain scale of iliac crest pain
Assessments of iliac crest pain at 6 weeks, 3 months, 6 months, 1 year and 2 years follow-up, by patients blinded to the side of graft harvesting from the iliac crest, will be analysed to investigate the relevance of donor site pain.
Time frame: During two years (24-27 months) after surgery
Correlation of posterior fusion rate to the presence of interbody fusion after one year
The correlation of the posterior fusion rate to the presence of interbody fusion will be assessed at the one year CT scans made for the primary objective.
Time frame: One year (12-15 months) after surgery
Posterior spinal fusion rate after two years
To determine the long-term fusion potential and behavior from AttraX® Putty and autograft, a comparison will be made between the fusion performance of both conditions after two years, assessed at CT-scans. Only those patients that scored a doubtful fusion or non-union in any of the relevant levels at the one-year CT scan will be scanned.
Time frame: Two years (24-27 months) after surgery