This invention promotes repair of damaged bone and bone tissue without the need for auto or synthetic grafts for improved defect healing.
Bone and bone tissue can only self-regenerate when the damage or defect is small, less than ~8mm. Larger defects require intervention to heal, and conventional treatment options are susceptible to failure due to the low rate of defect closure or the difficulty and/or complexity of the associated surgical procedures. For instance, autograft transplantation, grafting real bone from a patient’s body at a defect site, not only has a limited bone grafting supply, but is also associated with a number of complications including: sever herniation, vascular injury, donor site infection, neurologic injuries, hematoma, iliac fracture, and the need for revision surgery. Alternatively, synthetic materials have been used for grafting but are difficult to integrate with the host bone, often have trouble conforming to a defect, can cause disease such as osteoporosis, and still commonly require revision surgery. This technology allows for rapid repair of large bone and/or tissue defects without complex implant surgery and/or auto graft bone.
This invention is a composite device, tailored to fit a defect site, which degrades over a period of time while releasing locally, either concurrently or staggered, growth factors to induce and sustain bone regeneration. This technology mimics the natural healing cascade using a porous polymer membrane for controlled bone formation and bone tissue regeneration without fibrous tissue ingrowth in large defects by recapitulating the cellular regenerative process and providing structural support to guide said process. The membrane is composed using poly(lactic-coglycolic acid) (PLGA) and can be coated conformally with BMP-2, or other growth factors, using the Layber-by-Layer (LbL) approach which allows high loading and prevents exposure of sensitive growth factors to solvents used for membrane formation. The porosity and mechanical and degradation properties of the membrane may be easily manipulated for specific applications. The inventors have already shown multiweek sustained release of growth factor and rapid initiation of the closure of a critical defect, which would have not healed spontaneously, as early as 1 week post-surgery.
may be tailored to specific injury and the degradation, mechanical properties,
and porosity may be controlled
coating allows high loading and controlled release of one or more growth
factors on engineered timescales
fibrous tissue ingrowth
growth factors from solvents
release reduces risk of unwanted additional biological affects and/or toxicity