RCT of AttraX® Putty vs. Autograft in Instrumented Posterolateral Spinal Fusion (AxA)
Instrumented Spinal Fusion
Device: AttraX® Putty
Other: Autologous bone graft
|Study Design:||Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||A Randomized Controlled Trial of AttraX® Putty vs. Autograft in Instrumented Posterolateral Spinal Fusion|
- Posterior spinal fusion rate after one year [ Time Frame: One year (12-15 months) after surgery ]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.
- Rate of (serious) adverse events with a potential relation with AttraX® Putty [ Time Frame: Untill 2 years (24-27 months) after surgery ]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.
- Resorption characteristics of AttraX® Putty compared to autograft during the first year [ Time Frame: During the first year (12-15 months) after surgery ]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.
- Volume of bridging bone mass after one year [ Time Frame: One year (12-15 months) after surgery ]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.
- Visual analogue pain scale of iliac crest pain [ Time Frame: During two years (24-27 months) after surgery ]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.
- Correlation of posterior fusion rate to the presence of interbody fusion after one year [ Time Frame: One year (12-15 months) after surgery ]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.
- Posterior spinal fusion rate after two years [ Time Frame: Two years (24-27 months) after surgery ]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.
|Study Start Date:||October 2013|
|Estimated Primary Completion Date:||July 2017 (Final data collection date for primary outcome measure)|
Experimental: AttraX condition
8-10cc of AttraX® Putty per spinal level at the randomized allocation side of the spine (left or right).
Device: AttraX® Putty
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.
Active Comparator: Autograft condition
8-10cc autologous bone graft per spinal level at the control side of the spine. This can be a combination of local bone and iliac crest bone, but at least 50% of the volume has to be iliac crest bone graft.
Other: Autologous bone graft
Corticocancellous bone harvested from the iliac crest, with our without local bone obtained from decompression and/or preparation for fusion (facetectomy and denudement).
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.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01982045
|Onze Lieve Vrouwe Gasthuis|
|Amsterdam, Netherlands, 1091 AC|
|Arnhem, Netherlands, 6815 AD|
|Breda, Netherlands, 4818 CK|
|University Medical Center Utrecht|
|Utrecht, Netherlands, 3584 CX|
|Principal Investigator:||Moyo Kruyt, MD, PhD||UMC Utrecht|