Clinical Orthopaedics and Related Research ®

A Publication of The Association of Bone and Joint Surgeons ®

Basic Research 172 articles

Articles

Vancomycin Containing PLLA/β-TCP Controls MRSA In Vitro

Berna Kankilic MS, Erdal Bayramli PhD, Emine Kilic MS, Sezin Dağdeviren MS, Feza Korkusuz MD

Osteomyelitis caused by Methicillin-resistant Staphylococcus aureus (MRSA) often requires surgery and prolonged systemic antibiotic treatment. Local antibiotic delivery systems of bioceramics or polymers have been developed to treat osteomyelitis. A disadvantage of biodegradable polymers is the initial burst of antibiotics into the environment; one advantage of bioceramics is its osteoconductivity. We therefore developed a vancomycin-containing poly-l-lactic acid/β-tricalcium phosphate (PLLA/β-TCP) composite to control antibiotic release and stimulate bone formation.

Stiffness and Thickness of Fascia Do Not Explain Chronic Exertional Compartment Syndrome

Morten Dahl MD, Philip Hansen PhD, Per Stål DSc, David Edmundsson PhD, S. Peter Magnusson DSc

Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown.

Repeated Freeze-thaw Cycles Do Not Alter the Biomechanical Properties of Fibular Allograft Bone

Joshua M. Shaw MS, Shawn A. Hunter PhD, J. Christopher Gayton MD, Gregory P. Boivin DVM, Michael J. Prayson MD

Allograft tissues can undergo several freeze-thaw cycles between donor tissue recovery and final use by surgeons. However, there are currently no standards indicating the number of reasonable freeze-thaw cycles for allograft bone and it is unclear how much a graft may be degraded with multiple cycles.

Functional Restoration of Critically Sized Segmental Defects With Bone Morphogenetic Protein-2 and Heparin Treatment

Mela R. Johnson PhD, Joel D. Boerckel MS, Kenneth M. Dupont PhD, Robert E. Guldberg PhD

Bone defects and fracture nonunions remain a substantial challenge for clinicians. Grafting procedures are limited by insufficient volume and donor site morbidity. As an alternative, biomaterial scaffolds functionalized through incorporation of growth factors such as bone morphogenetic proteins (BMPs) have been developed and appear to regenerate the structure and function of damaged or degenerated skeletal tissue.

Tendinosis-like Histologic and Molecular Changes of the Achilles Tendon to Repetitive Stress: A Pilot Study in Rats

Nam Soon Cho MD, Ji Hye Hwang MD, PhD, Yong Taek Lee MD, PhD, Seoung Wan Chae MD, PhD

Tendinopathy (pain and tendon degeneration) is associated with repetitive use and mechanical overload. However, the etiology of tendinopathy remains unclear. Clarification of histologic and molecular changes of tendon to repetitive stress could provide better understanding of Achilles tendon disorders related to repetitive stress.

Osteosarcoma Cells Differentiate into Phenotypes from all Three Dermal Layers

Scott Russinoff MD, Sara Miran BS, Ashok L. Gowda MD, Paul A. Lucas PhD

Osteosarcomas are the most common solid malignant bone tumors, but little is known of their origin. The embryonal rest hypothesis views cancer cells as arising from committed progenitor stem cells in each tissue. Adult tissue contains primitive stem cells that retain the ability to differentiate across dermal lines, raising the possibility that the stem cell of origin of cancers may be from a more primitive stem cell than a progenitor.

Emerging Ideas: Can Erythromycin Reduce the Risk of Aseptic Loosening?

Weiping Ren MD, PhD, David C. Markel MD

Persistent inflammatory reaction to wear debris causes periprosthetic osteolysis and loosening. Some authors have advocated pharmaceutical approaches to reduce the inflammatory reaction. Erythromycin has antiinflammatory effects independent of its antimicrobial properties. Although oral erythromycin reportedly inhibits periprosthetic tissue inflammation in patients with aseptic loosening, long-term systematic erythromycin treatment is not recommended owing to its side effects. Therefore, it would be advantageous to restrict erythromycin delivery to the inflammatory periprosthetic tissue without causing side effects.

Influence of Gender and Fixation Stability on Bone Defect Healing in Middle-aged Rats: A Pilot Study

Manav Mehta PhD, Georg N. Duda PhD, Carsten Perka MD, Patrick Strube MD

Gender and stability of fixation independently influence bone regeneration but their combined effects are unclear.

Delayed Fracture Healing in Growth Differentiation Factor 5-deficient Mice: A Pilot Study

Cynthia M. Coleman PhD, Brooke H. Scheremeta DO, Amanda T. Boyce PhD, Robert L. Mauck PhD, Rocky S. Tuan PhD

Growth differentiation factor-5 (GDF-5) is a key regulator of skeletogenesis and bone repair and induces bone formation in spinal fusions and nonunion applications by enhancing chondrocytic and osteocytic differentiation and stimulating angiogenesis. Elucidating the contribution of GDF-5 to fracture repair may support its clinical application in complex fractures.

Evaluation of Two Sources of Calcium Sulfate for a Local Drug Delivery System: A Pilot Study

Ashley C. Parker BS, J. Keaton Smith MS, Harry S. Courtney PhD, Warren O. Haggard PhD

Local drug delivery has substantial potential to prevent infections compared with systemic delivery. Although calcium sulfate (CaSO) has been studied for local drug delivery and two types are commercially available, it is unknown whether they differentially release antibiotics.