Journal of Pain Research (Aug 2023)
Early Clinical Results of Intervertebral Joint Stabilization by Injectable Load-Sharing Polymers
Abstract
Thomas Hedman,1 James Yu,2 Harwant Singh,3 Timothy Deer4 1F. Joseph Halcomb III, M.D. Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA; 2Sydney Spine and Pain, Waratah Private Hospital, Hurstville, New South Wales, Australia; 3Spine and Joint Centre, Pantai Hospital, Kuala Lumpur, Malaysia; 4The Spine and Nerve Center of the Virginias, Charleston, WV, USACorrespondence: Thomas Hedman, Tel +1 512 818-8468, Email [email protected]: Genipin is a polymer-forming collagen bonding substance that can be dissolved in a buffered carrier and injected into disc annulus tissues. Therapeutic benefit is derived from the mechanical support provided by a large number of genipin polymers attached to collagen fibers in a degraded disc.Study Design/Setting: IRB-approved prospective, multi-site, single-arm, 12-month feasibility studies were undertaken in two countries to evaluate the safety and efficacy of the genipin-based implant for treating discogenic chronic low back pain (CLBP).Patient Sample: Twenty CLBP patients with symptomatic discs at one or two levels were enrolled in the study.Outcome Measures: The primary safety endpoint was serious adverse events at 1 month, and the primary efficacy endpoint was reduction of pain and disability at 3 months. Secondary efficacy endpoints included reduction of pain and disability at 2 weeks, 1 month, 6 months, and 12 months; reduction of flexion–extension instability; increase in segmental lordosis and rotation; and patient satisfaction.Methods: Fluoroscopic image-guidance was used to deliver two posterolateral injections of buffered genipin to each symptomatic disc. Flexion–extension radiographs were used to quantify joint kinematics at three time-points.Results: Clinically meaningful improvements in pain and disability scores were reported in 80% or more of patients from 2 weeks to 1 year post-treatment. For the more severely unstable joints, treatment significantly reduced the instability score from a pre-treatment level of 2.4 standard deviations above the mean for an asymptomatic population to the asymptomatic mean at the 3-month follow-up.Conclusion: These initial clinical data demonstrate the safety and efficacy of a genipin-based collagen tethering device capable of improving spinal joint stability while successfully addressing CLBP. This work merits additional randomized clinical studies.Keywords: disc disease, lumbar spine, collagen, degenerative disc disease
