An injectable self-adaptive polymer as a drug carrier for the treatment of nontraumatic early-stage osteonecrosis of the femoral head

Abstract

Core decompression (CD) with the elimination of osteonecrotic bone is the most common strategy for treating early-stage nontraumatic osteonecrosis of the femoral head (ONFH). Adjuvant treatments are widely used in combination with CD as suitable methods of therapy. Existing augmentations have to be fabricated in advance. Here, we report a novel injectable glycerin-modified polycaprolactone (GPCL) that can adapt to the shape of the CD cavity. GPCL shows great flowability at 52.6 °C. After solidification, its compressive modulus was 120 kPa at body temperature (37 °C). This excellent characteristic enables the polymer to provide mechanical support in vivo. In addition, GPCL acts as a carrier of the therapeutic agent zoledronic acid (ZA), demonstrating sustained release into the CD region. ZA-loaded GPCL was injected into ONFH lesions to treat early-stage nontraumatic cases. Compared to that in the CD group, CD+ZA-loaded GPCL injection preserved bone density and increased the collagen level in the femoral head. At the interface between the GPCL and CD tunnel wall, osteogenesis was significantly promoted. In addition, morphological evaluations revealed that the femoral heads in the CD+ZA-GPCL group exhibited improved pressure resistance. These results suggest a strategy effective to preserve the bone density of the femoral head, thus decreasing the possibility of femoral head collapse. This novel injectable polymer has, therefore, considerable potential in clinical applications.

The polycaprolactone and silk fibroin nanofibers with Janus-structured sheaths for antibacterial and antioxidant by loading Taxifolin

“…In the realm of bio-medical applications, biodegradable and resorbable polymers—highlighted by polycaprolactone (PCL) and poly(α- l -glutamic acid)—have been integral to advancements in tissue engineering, drug delivery systems, wound healing, scaffold construction, and the development of surgical sutures [ 5 ]. The robust properties of PCL, an FDA-approved polyester, which include remarkable strength, tunable biodegradability, non-cytotoxicity, and biocompatibility, have solidified its role in a variety of applications in the current tissue engineering domain [ 6 , 7 ]. As a result, PCL possesses exceptional toughness, mechanical strength, and biocompatibility, it has been employed in tissue-engineering scaffolds to repair skin, vascular tissues, and bone [ 8 ].…”