the emphasis is mine.....
Inhibiting Postoperative Spinal Fibrosis: Clinical Studies
with ADCON-L
Meeting: CNS 1998 Seattle, Washington
Presentation type: Slide
Authors: Stewart Dunsker, M.D., William Tobler, M.D., The ADCON-L Study Group
Abstract:
Purpose: ADCON¨-L, shown to inhibit the development of peridural spinal adhesions in animals, was
evaluated for safety and effectiveness in preventing postoperative adhesions in patients. In addition, the
study evaluated the association between fibrosis and clinical outcome. Methods: The studies were
designed as controlled, randomized, double-blind clinical trials and were conducted at nine European
centers (pivotal study, N = 298), and 16 U.S. centers (supporting study, N = 223 for interim analysis).
The studies included patients undergoing first-time, unilateral, single-level, discectomy at the L4/L5 or
L5/S1 level. Patients received ADCON¨-L gel or no treatment (Control). Fibrosis was quantified 6
months postoperatively by MRI, and evaluated visually in cases of reoperation. Outcome measures
included straight leg raise (SLR) exam, low back pain, and activity-related pain (ARP) in the pivotal, and
the Roland Morris Disability Questionnaire (RM) in the supporting study. A numerical clinical utility index
was developed and calculated for each treatment group based upon decreased peridural scar and
improvement in all clinical outcome measures. A post-study surveillance was conducted on data from
pivotal study patients who returned for 12 month postoperative assessments. Results: Pivotal study data
shows that extensive scar is significantly associated with recurrent radicular pain (p = 0.004), low back
pain (p = 0.03), worse SLR (p = 0.05), and increased ARP (p = 0.008). ADCON¨-L patients had
significantly less scar than control patients 6 months postoperatively (p = 0.002), supported by interim
analysis of the data from the supporting study (p = 0.005), and maintained to 12 months (p = 0.01). A
meta-analysis was performed combining data from both clinical studies, and demonstrated further that
ADCON¨'-L patients had significantly less scar than control patients (p = 0.001, N = 407 evaluable
patients). When reoperation was required, the surgeons encountered less fibrosis in the ADCON¨*-L
patients compared to control patients. Fewer ADCON¨-L patients experienced an increase in ARP (p =
0.013), and ADCON¨-L patients had improved SLR exams (p = 0.037), both of which were maintained
at 12 months. ADCON¨-L treated patients had less back pain (p < 0.05) compared to control patients.
There was a significant reduction in the RM score for ADCON¨-L treated patients in the interim analysis
of the supporting study (p = 0.016). Significantly more ADCON¨-L patients were classified as clinical
successes using the clinical utility index for the pivotal study at 6 months (p = 0.002), and 12 months (p =
0.0 13), and for the interim data from the supporting study (p = 0.002). There were no differences
between the device and control groups in neurological tests, adverse events or wound healing
characteristics. Summary: The group of patients who received ADCON¨-L have less scar and a better
clinical outcome one year after laminectomy compared to those patients who did not receive the
treatment. ADCON¨-L treatment was safe and effective in reducing postoperative peridural scar. |
