Clinical Orthopaedics and Related Research ®

A Publication of The Association of Bone and Joint Surgeons ®

Basic Research 169 articles


Fractures in Geriatric Mice Show Decreased Callus Expansion and Bone Volume

Luke A. Lopas MD, Nicole S. Belkin MD, Patricia L. Mutyaba BS, Chancellor F. Gray MD, Kurt D. Hankenson DVM, MS, PhD, Jaimo Ahn MD, PhD

Poor fracture healing in geriatric populations is a significant source of morbidity, mortality, and cost to individuals and society; however, a fundamental biologic understanding of age-dependent healing remains elusive. The development of an aged-based fracture model system would allow for a mechanistic understanding that could guide future biologic treatments.

Do Genetic Susceptibility, Toll-like Receptors, and Pathogen-associated Molecular Patterns Modulate the Effects of Wear?

Edward M. Greenfield PhD

Overwhelming evidence supports the concept that wear particles are the primary initiator of aseptic loosening of orthopaedic implants. It is likely, however, that other factors modulate the biologic response to wear particles. This review focuses on three potential other factors: genetic susceptibility, Toll-like receptors (TLRs), and bacterial pathogen-associated molecular patterns (PAMPs).

A Novel System Improves Preservation of Osteochondral Allografts

James L. Cook DVM, PhD, Aaron M. Stoker PhD, James P. Stannard MD, Keiichi Kuroki DVM, PhD, Cristi R. Cook DVM, MS, Ferris M. Pfeiffer PhD, Chantelle Bozynski DVM, MSc, Clark T. Hung PhD

Osteochondral allografting is an option for successful treatment of large articular cartilage defects. Use of osteochondral allografting is limited by graft availability, often because of loss of chondrocyte viability during storage.

Are Copy Number Variants Associated With Adolescent Idiopathic Scoliosis?

Jillian G. Buchan MS, David M. Alvarado PhD, Gabe Haller PhD, Hyuliya Aferol BS, Nancy H. Miller MD, Matthew B. Dobbs MD, Christina A. Gurnett MD, PhD

Adolescent idiopathic scoliosis (AIS) is a complex genetic disorder that causes spinal deformity in approximately 3% of the population. Candidate gene, linkage, and genome-wide association studies have sought to identify genetic variation that predisposes individuals to AIS, but the genetic basis remains unclear. Copy number variants are associated with several isolated skeletal phenotypes, but their role in AIS, to our knowledge, has not been assessed.

Does Activity Affect Residual Limb Skin Temperatures?

Glenn K. Klute PhD, Elizabeth Huff MS, William R. Ledoux PhD

Many lower limb amputees experience thermal discomfort as a result of wearing a prosthesis. The development of new prosthetic technology to address thermal discomfort requires an understanding of how activity (or inactivity) affects residual limb skin temperatures and how skin temperatures are mapped across the skin-prosthesis interface.

How Has the Introduction of New Bearing Surfaces Altered the Biological Reactions to Byproducts of Wear and Modularity?

Paul H. Wooley PhD

Biological responses to wear debris were largely elucidated in studies focused on conventional ultrahigh-molecular-weight polyethylene (UHMWPE) and some investigations of polymethymethacrylate cement and orthopaedic metals. However, newer bearing couples, in particular metal-on-metal but also ceramic-on-ceramic bearings, may induce different biological reactions.

Does Vitamin E-blended UHMWPE Prevent Biofilm Formation?

Dustin L. Williams PhD, John Vinciguerra BS, Julia M. Lerdahl, Roy D. Bloebaum PhD

Biofilm-related periprosthetic infections are catastrophic to patients and clinicians. Data suggest the addition of vitamin E to UHMWPE may have the ability to reduce biofilm formation on the surface of UHMWPE; however, previous studies were performed using stagnant broth solutions that may not have simulated a physiologic environment. In addition, the observed differences in levels of bacterial attachment, though statistically significant, may not be clinically significant.

Surgical Revascularization in Structural Orthotopic Bone Allograft Increases Bone Remodeling

Wouter F. Willems MD, Thomas Kremer MD, Patricia Friedrich AAS, Allen T. Bishop MD

Osseous defects reconstructed with cryopreserved structural allografts are poorly revascularized and therefore are prone to nonunion, infection, deterioration of mechanical properties, and fracture. Whether this can be mitigated by specific interventions such as intramedullary surgical revascularization has been incompletely evaluated.

Does Use of a Powered Ankle-foot Prosthesis Restore Whole-body Angular Momentum During Walking at Different Speeds?

Susan D’Andrea PhD, Natalie Wilhelm BA, Anne K. Silverman PhD, Alena M. Grabowski PhD

Whole-body angular momentum (H) influences fall risk, is tightly regulated during walking, and is primarily controlled by muscle force generation. People with transtibial amputations using passive-elastic prostheses typically have greater H compared with nonamputees.

Uncultured Autogenous Adipose-derived Regenerative Cells Promote Bone Formation During Distraction Osteogenesis in Rats

Issei Nomura MD, Koji Watanabe MD, PhD, Hidenori Matsubara MD, PhD, Katsuhiro Hayashi MD, PhD, Naotoshi Sugimoto MD, PhD, Hiroyuki Tsuchiya MD, PhD

Adipose-derived stem cells have recently shown differentiation potential in multiple mesenchymal lineages in vitro and in vivo. These cells can be easily isolated in large amounts from autologous adipose tissue and used without culturing or differentiation induction, which may make them relatively easy to use for clinical purposes; however, their use has not been tested in a distraction osteogenesis model.