Orthobiologics in the Foot and Ankle.

Many allogeneic biologic materials, by themselves or in combination with cells or cell products, may be transformative in healing or regeneration of musculoskeletal bone and soft tissues. By reconfiguring the size, shape, and methods of tissue preparation to improve deliverability and storage, unique iterations of traditional tissue scaffolds have emerged. These new iterations, combined with new cell technologies, have shaped an exciting platform of regenerative products that are effective and provide a bridge to newer and better methods of providing care for orthopedic foot and ankle patients.

Induction of neural tissue markers by micronized human spinal cord implants.

The osteoinductive capacity of biological noncellular material has been widely recognized. Studies using bone morphogenetic proteins and acellular bone matrix demonstrate that host mesenchymal cells can be readily transformed into osteoprogenitor cells. The current study sought to determine whether another biological noncellular material, human spinal cord matrix, could induce transformation of host cells into a neural lineage.

Carboxyl-modified single-wall carbon nanotubes improve bone tissue formation in vitro and repair in an in vivo rat model.

The clinical management of bone defects caused by trauma or nonunion fractures remains a challenge in orthopedic practice due to the poor integration and biocompatibility properties of the scaffold or implant material. In the current work, the osteogenic properties of carboxyl-modified single-walled carbon nanotubes (COOH-SWCNTs) were investigated in vivo and in vitro. When human preosteoblasts and murine embryonic stem cells were cultured on coverslips sprayed with COOH-SWCNTs, accelerated osteogenic differentiation was manifested by increased expression of classical bone marker genes and an increase in the secretion of osteocalcin, in addition to prior mineralization of the extracellular matrix.

Use of corticocancellous allogeneic bone blocks for augmentation of alveolar bone defects.

Purpose: The use of autogenous block bone grafts in bone regeneration procedures for alveolar ridge augmentation can be limited by donor site morbidity and complications. The purpose of the present study was to evaluate the efficacy of allogeneic corticocancellous iliac block grafts used for ridge augmentation prior to implant placement.

Materials And Methods: Forty-one patients with severe ridge volume deficiency underwent augmentation using allogeneic corticocancellous iliac block bone grafts.

A comparison of two microbial detection methods used in aseptic processing of musculoskeletal allograft tissues.

Tissues from 78 musculoskeletal donors were concurrently tested for microorganisms using both a swab and liquid culture method. An aggregate total of 20 organisms were detected by both methods. The swab detected 4/20 organisms while the liquid culture detected 18/20 organisms.

Cancellous and cortical microparticulate allograft for dental implantation: an experimental study in non-human primates.

Background: : A comparison of freeze-dried cancellous and cortical particulate bone allograft was made using a non-human primate model.

Methods And Materials: : Microparticulate bone allograft (90-300 μm size) made from either cortical or cancellous bone was used to pack standard bone defects in the lower extremities of baboons, Papio hamadryas. Bone allografts were aseptically processed and freeze dried.

Proximal humerus reconstructions for tumors.

Unlabelled: The optimal method for reconstructing the proximal humerus in patients with tumors is controversial. To determine functional outcomes and complication rates after different types of reconstructions, we reviewed a consecutive series of 49 patients who underwent proximal humerus resection and osteoarticular allograft (17 patients), allograft-prosthetic composite (16), or endoprosthetic (16) reconstruction. Operative indications included primary malignancies (24 patients), metastatic disease (19), and benign aggressive disease (six).

Microparticulate cortical allograft: an alternative to autograft in the treatment of osseous defects.

Benign bone tumors are commonly diagnosed and treated. Following tumor removal, the defect in the bone can be filled with auto- or allografts, (degradable) bone substitutes or non-degradable polymethylmethacrylate. The ideal substitute for this purpose should provide immediate structural support and readily incorporate into bone over a short period of time.

Changes in vertebral bodies adjacent to acutely narrowed intervertebral discs: observations in baboons.

Study Design: The study used nonhuman primates to investigate changes in the vertebral bodies adjacent to acutely narrowed intervertebral discs.

Objective: To describe changes in the vertebral bodies adjacent to acutely narrowed intervertebral discs in the lumbar spine.

Summary Of Background Data: Alterations in the intervertebral disc are known to affect the adjacent vertebral bodies.

Comparison of frozen and freeze-dried particulate bone allografts.

Freeze-dried and frozen particulate bone allografts are used interchangeably on the assumption that the biologic behavior of these grafts is similar. Dissimilarities in biologic behavior and differences in the rate and extent of bone incorporation of freeze-dried and frozen particulate grafts were demonstrated in a comparative study using a non-human primate model. Freeze-dried particulate allografts induced new bone formation and healing of the osseous defects much faster than the frozen allografts.

Distal tibial osteoarticular allografts.

Osteoarticular allografts can be used for limb reconstruction following tumor excision. Most commonly, the distal femur, proximal tibia and distal radius have been studied, while distal tibial allografts receive only sporadic mention in the literature. We evaluated the functional outcomes of distal tibial allografts used in tumor reconstruction.

Effect of hydrogen peroxide on osteoinduction by demineralized bone.

The osteoinductive capacity of demineralized bone matrix (DBM) has led to wide use of this material for surgical reconstruction. Preparation of DBM often includes sterilization with ethylene oxide, disinfection with various chemical agents, or irradiation. Exposure to hydrogen peroxide (H2O2) is used for both sterilization and bleaching of bone, the latter primarily for cosmetic reasons.

Particulate bone allograft incorporation in regeneration of osseous defects; importance of particle sizes.

Packing of bone defect with particulate allografts is a commonly performed clinical procedure. However, the ideal size of bone particles used to fill bone defects is ill-defined. For this reason the study of biology of bone allografts with different particle sizes has been performed.

Transplantation of osteochondral allografts after cold storage.

Background: Transplantation of fresh osteochondral allografts stored at hypothermia into knee cartilage defects is a common procedure; however, the length of time that allografts can be stored prior to transplantation is controversial and has been determined, in part, by the results of vital stain uptake by chondrocytes. This study was performed to further define the limits of allograft storage.

Methods: Articular cartilage from six cadavers was stored for up to fifty-one days in tissue-culture media, and histologic sections were evaluated histomorphometrically to quantify the loss of chondrocytes.

Salvage of failed massive allograft reconstruction with endoprosthesis.

Unlabelled: A subset of osteoarticular allograft reconstructions after tumor resection ultimately will fail in patients achieving long-term survival. There are several alternative surgical approaches to revising these reconstructions. We retrospectively evaluated the outcome of 20 patients who had allograft reconstruction with a modular endoprosthesis.

Bone and tissue allograft use by orthopaedic surgeons.

The purpose of our study was to determine the involvement of orthopaedic surgeons in the process of acquiring allografts they transplant. A questionnaire regarding allograft acquisition and use was directed to 340 hospitals. In approximately 85% of the institutions, nonorthopaedic personnel selected and acquired the allografts.

Recurrent aggressive chondrosarcoma of the middle phalanx of the index finger: excision and reconstruction with an osteocartilaginous allograft.

Introduction: Chondrosarcomas are malignant tumours and need to be treated aggressively including ablative surgery. Bovée et al. and Mankin have recently drawn attention to a less aggressive behaviour of chondrosarcomas of the phalanges compared with those of other localizations including the metacarpals.

Blood and marrow cultures as indicators of bone contamination in cadaver donors.

Of 770 cadaver bone donors evaluated, 185 had positive blood or ilium marrow aspirate cultures. These donors were matched with an immediately preceding or subsequent donor with negative blood and marrow cultures. Donors with cultures positive for skin contaminants only were not included in the study.

Allograft reconstruction after resection of malignant tumors of the scapula.

The oncologic and functional outcomes of six patients who had scapular allograft reconstruction after scapulectomy for malignant tumors were reviewed. Five patients had Stage IIB and one patient had Stage IB tumors. Total scapulectomy was done in five patients, and partial scapulectomy (glenoid and neck) was done in one patient.

A study of retrieved allografts used to replace anterior cruciate ligaments.

Purpose: The purpose of the study was the examination of retrieved whole anterior cruciate ligament (ACL) replacement grafts to determine the rate and the extent of cellular replacement and remodeling of the grafts.

Type Of Study: Gross and histopathologic examination of specimens.

Methods: Nine specimens of ACL replacement allografts and 1 autograft were obtained at autopsy and surgical procedures.