tetracycline and Tibial-Fractures

The aim of this study was to compare angiogenesis and osteogenesis occurring within 8.0 mm diaphyseal defects created in canine tibiae treated using autograft or a biodegradable bone scaffold. All tibiae were reamed to 7.0 mm and fixed with a 6.5-mm statically locked intramedullary nail. Each of the 18 canines as allotted to one of three treatment groups: (1) left empty (N = 5), (2) treated with iliac crest autograft (N = 6), or (3) treated with a PLGA/calcium phosphate biodegradable scaffold (N = 7). Fluorescent markers were given at successive time periods: calcein green at 6 weeks, xylenol orange at 9 weeks, and tetracycline at 11 and 14 weeks. Animals were sacrificed at 15 weeks and their legs were perfused with a radio opaque compound. Samples were analyzed using Micro CT, bright-field microscopy and fluorescent microscopy. Scaffold samples were found to have significantly greater bone formation (p = 0.015) and blood vessel formation (p < 0.001) at their osteotomy sites than autograft samples. Bone formation rate in the periosteum was significantly greater in the autograft samples than the scaffold samples for all time periods. Bone formation at the osteotomy site was found to be significantly greater when associated with greater blood vessel formation (p = 0.026). The PLGA/calcium phosphate biodegradable scaffold we have employed supports angiogenesis within a segmental tibial defect that has adequate soft tissue coverage.

Topics: Absorbable Implants; Animals; Bone Substitutes; Bone Transplantation; Calcium Phosphates; Disease Models, Animal; Dogs; Fluoresceins; Fluorescent Dyes; Fracture Fixation, Intramedullary; Fracture Healing; Ilium; Lactic Acid; Neovascularization, Physiologic; Osteogenesis; Osteotomy; Phenols; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Radiography; Sulfoxides; Tetracycline; Tibial Fractures; Time Factors; Tissue Scaffolds; Transplantation, Homologous; Xylenes

We encountered a patient who developed metallosis after total knee arthroplasty (TKA), resulting in loosening of the implant, bone resorption, reduced bone formation, and fracture. The implant was replaced with a NexGen modular revision TKA system after autologous bone and hydroxyapatite granule grafting. Histopathologic examination showed accumulation of metallic debris and tartrate-resistant acid phosphatase-positive cells around the trabecular and cortical bone. Examination of hard tissue specimens showed a reduced bone volume (determined by bone histomorphometry) and an increase of all osteoid parameters, indicating disturbance of mineralization in addition to increased bone resorption.

Topics: Aged; Arthroplasty, Replacement, Knee; Bone Resorption; Calcification, Physiologic; Female; Foreign-Body Reaction; Humans; Osteogenesis; Osteolysis; Postoperative Complications; Prosthesis Failure; Radiography; Tetracycline; Tibia; Tibial Fractures; Titanium

Topics: Age Factors; Animals; Epiphyses; Fractures, Bone; Fractures, Closed; Radiography; Rats; Tetracycline; Tibia; Tibial Fractures; Wound Healing

Topics: Animals; Bone Resorption; Femoral Fractures; Fluorescence; Fracture Fixation; Hematoporphyrins; Osteogenesis; Periosteum; Radiography; Rats; Tetracycline; Tibial Fractures; Wound Healing

Topics: Animals; Bone and Bones; Bone Regeneration; Female; Fluoresceins; Fracture Fixation, Intramedullary; Hematoporphyrins; Male; Methods; Osteotomy; Rabbits; Radiography; Tetracycline; Tibia; Tibial Fractures; Wound Healing

Topics: Animals; Bone and Bones; Bone Regeneration; Fibula; Fractures, Bone; Haversian System; Humans; Rabbits; Rats; Tetracycline; Tibial Fractures; Wound Healing

Topics: Angiography; Bony Callus; Cortisone; Fluorescence; Fractures, Bone; Microradiography; Microscopy; Microscopy, Fluorescence; Oxytetracycline; Pharmacology; Physiology; Rats; Research; Tetracycline; Tibial Fractures