Abstract
Lumbar disc herniation is one of the most common degenerative spinal conditions resulting in lower back pain and sciatica. Surgical treatment options include microdiscectomy, lumbar fusion, total disc replacement, and other minimally invasive approaches. At present, microdiscectomy procedures are the most used technique; however, the annulus fibrosus is left with a defect that without treatment may contribute to high reherniation rates and changes in the biomechanics of the lumbar spine. This paper aims to review current commercially available products that mechanically close the annulus including the AnchorKnot® suture-passing device and the Barricaid® annular closure device. Previous studies and reviews have focused mainly on a biomimetic biomaterials approach and have described some mechanical and biological requirements for an active annular repair/regeneration strategy but are still far away from clinical implementation. Therefore, in this paper we aim to create a design specification for a mechanical annular closure strategy by identifying the most important mechanical and biological design parameters, including consideration of material selection, preclinical testing requirements, and requirements for clinical implementation.
Highlights
Degenerative changes in the intervertebral discs (IVDs) can cause a loss of hydration in the nucleus pulposus reducing IVD height. This leads to a greater load transfer to the surrounding annulus fibrosus (AF) creating microstructural damage in the fibers that with time can develop into bigger tears [7,8]
If any annular healing occurs after discectomy, it is believed to happen thatslowly patients with large annular defects (≥6 mm) after lumbar discectomy have higher risk and results in biomechanically inferior tissue with reduced capacity for symptom recurrence to those with small annular to accommodate tensile and forcesreoperation
If any annular healing occurs after discectomy, it is believed to tissue engineering is investigating biomimetic approaches to replicate the lamellar structure slowly and results in biomechanically inferior tissue with reduced capacity to and induce regeneration [28]; the avascular nature of this region and the low accommodate tensile forces [19]
Summary
Low back pain is among the leading causes of disability in the world [1]. Injury or degeneration of intervertebral discs (IVDs) in the spine can be a cause of this disability. The IVD consists of a central nucleus pulposus, an irregular meshwork of collagen II fibrils with an osmotic swelling pressure created by large amounts of proteoglycan aggrecan aggregated along chains of hyaluronan This is surrounded by the annulus fibrosis, collagen I fibers oriented in oblique angles in a heterogeneous structure in distinct lamellae, with the collagen fibers laid up in alternating oblique angles in each consecutive lamella to form an angle-ply architecture [2,3,4,5,6]. Degenerative changes in the intervertebral discs (IVDs) can cause a loss of hydration in the nucleus pulposus reducing IVD height. This leads to a greater load transfer to the surrounding annulus fibrosus (AF) creating microstructural damage in the fibers that with time can develop into bigger tears [7,8].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
