Clinical Orthopaedics and Related Research ®

A Publication of The Association of Bone and Joint Surgeons ®

Basic Research 173 articles


Do Longer Surgical Procedures Result in Greater Contamination of Surgeons’ Hands?

Pooria Hosseini MD, MSc, Gregory M. Mundis MD, Robert Eastlack MD, Allen Nourian MD, Jeff Pawelek BS, Stacie Nguyen MPH, Behrooz A. Akbarnia MD

A surgical site infection is a substantial cause of complications in patients. Different methods are being used to decrease surgical site infections; however, these infections still can cause complications, especially in patients undergoing longer operations (> 3 hours). There is evidence that the efficacy of the scrubbing material fades after 3 hours. However, we do not know the longevity of hand cleanliness after application of scrubbing materials in a long operation. It can be postulated that if the surgeon’s scrubbed hands are recolonized after a certain time, they may serve as a progressive source of contamination during surgery.

Does a PEEK Femoral TKA Implant Preserve Intact Femoral Surface Strains Compared With CoCr? A Preliminary Laboratory Study

Kathryn E. Rankin PhD, Alexander S. Dickinson PhD, Adam Briscoe PhD, Martin Browne PhD

Both the material and geometry of a total knee arthroplasty (TKA) component influence the induced periprosthetic bone strain field. Strain, a measure of the local relative deformation in a structure, corresponds to the mechanical stimulus that governs bone remodeling and is therefore a useful in vitro biomechanical measure for assessing the response of bone to new implant designs and materials. A polyetheretherketone (PEEK) femoral implant has the potential to promote bone strains closer to that of natural bone as a result of its low elastic modulus compared with cobalt-chromium (CoCr).

Functional Assessment of Clubfoot Associated HOXA9, TPM1, and TPM2 Variants Suggests a Potential Gene Regulation Mechanism

Katelyn S. Weymouth PhD, Susan H. Blanton PhD, Tamar Powell MS, Chandrashekhar V. Patel PhD, Stuart A. Savill PhD, Jacqueline T. Hecht PhD

Isolated nonsyndromic clubfoot is a common birth defect affecting 135,000 newborns worldwide each year. Although treatment has improved, substantial long-term morbidity persists. Genetic causes have been implicated in family-based studies but the genetic changes have eluded identification. Previously, using a candidate gene approach in our family-based dataset, we identified associations between clubfoot and four single nucleotide polymorphisms (SNPs) located in potential regulatory regions of genes involved in muscle development and patterning () and muscle function (and) were identified.

Implant-delivered Alendronate Causes a Dose-dependent Response on Net Bone Formation Around Porous Titanium Implants in Canines

Jenny Ann Pura MSc, J. Dennis Bobyn PhD, Michael Tanzer MD

Bony fixation of cementless orthopaedic implants is not always achieved, particularly in challenging scenarios such as revision surgery, trauma, and tumor reconstruction. An adjunct therapy for improving porous implant fixation could improve the reliability and durability of these reconstructive procedures.

What Are the Biomechanical Effects of Half-pin and Fine-wire Configurations on Fracture Site Movement in Circular Frames?

Daniel J. Henderson FRCS (Orth), Jeremy L. Rushbrook FRCS (Orth), Todd D. Stewart PhD, Paul J. Harwood FRCS (Orth)

Fine-wire circular frame (Ilizarov) fixators are hypothesized to generate favorable biomechanical conditions for fracture healing, allowing axial micromotion while limiting interfragmentary shear. Use of half-pins increases fixation options and may improve patient comfort by reducing muscle irritation, but they are thought to induce interfragmentary shear, converting beam-to-cantilever loading. Little evidence exists regarding the magnitude and type of strain in such constructs during weightbearing.

Does Sclerostin Depletion Stimulate Fracture Healing in a Mouse Model?

Mohammad M. Alzahrani MD, MSc, Frank Rauch MD, Reggie C. Hamdy MB, MSc(Ortho), FRCS(C)

Sclerostin is a secreted glycoprotein that inhibits the intracellular Wnt signaling pathway, which, when inactivated, stimulates bone formation. This has been seen in fracture studies, which have shown larger and stronger calluses with accelerated fracture healing in sclerostin knockout and sclerostin antibody injection models. However, the effects of these two mechanisms have not been compared in the context of fracture healing.

Gamma Radiation Sterilization Reduces the High-cycle Fatigue Life of Allograft Bone

Anowarul Islam MS, Katherine Chapin BS, Emily Moore BS, Joel Ford MD, Clare Rimnac PhD, Ozan Akkus PhD

Sterilization by gamma radiation impairs the mechanical properties of bone allografts. Previous work related to radiation-induced embrittlement of bone tissue has been limited mostly to monotonic testing which does not necessarily predict the high-cycle fatigue life of allografts in vivo.

Transcriptional Profiling Identifies the Signaling Axes of IGF and Transforming Growth Factor-β as Involved in the Pathogenesis of Osteosarcoma

Rui Yang MD, Sajida Piperdi MS, Yue Zhang PhD, Wei Zhu PhD, Neophytos Neophytou PhD, Bang H. Hoang MD, Gary Mason MD, David Geller MD, Howard Dorfman MD, Paul A. Meyers MD, John H. Healey MD, Donald G. Phinney PhD, Richard Gorlick MD

Osteosarcoma is the most common primary bone tumor in adolescents associated with skeletal development. The molecular pathogenesis of osteosarcoma has not been completely determined, although many molecular alterations have been found in human osteosarcomas and cell lines.

Allogeneic and Autogenous Bone Grafts Are Affected by Historical Donor Environmental Exposure

Caleb Behrend MD, Jonathon Carmouche MD, Paul W. Millhouse MD, Lauren Ritter MPH, Joseph Moskal MD, Paul Rubery MD, Edward Puzas PhD

Bone graft materials are routinely evaluated for infectious agents; however, data regarding contamination of bone graft from environmental exposure of the donors to osteotoxic substances such as lead are not routinely available. In animal models, stored lead in bone has been shown to impair fracture healing and osteocyte function. In clinical studies, lead is linked to skeletal disease at relatively low concentrations. Presumably the levels of lead in allografts mirror the level of lead in bone in the population; however, the degree to which processing might decrease this and the frequency with which potentially osteotoxic levels appear in bone grafts have not been studied.

Can Near-infrared Spectroscopy Detect and Differentiate Implant-associated Biofilms?

John E. Tidwell MD, Ben Dawson-Andoh PhD, Emmanuel O. Adedipe PhD, Kofi Nkansah MS, Matthew J. Dietz MD

Established bacterial diagnostic techniques for orthopaedic-related infections rely on a combination of imperfect tests that often can lead to negative culture results. Spectroscopy is a tool that potentially could aid in rapid detection and differentiation of bacteria in implant-associated infections.