Overview of Services

The Imaging and Biomechanical Testing core offer imaging and mechanical testing of bones and other constructs. High-resolution micro-computed tomography (µCT) provides non-destructive, quantitative and qualitative assessment of trabecular and cortical bone microarchitecture. µCT is particularly useful for studies that utilize animal models to examine the effects of genetic manipulations, mechanical stimuli and/or pharmacological agents on skeletal characteristics. It is also useful for characterizing scaffolds used for tissue engineering applications. We are able to scan ex vivo samples that are up to 36 mm in diameter and 80 mm in length at resolutions down to 8 µm (µCT40, Scanco Medical AG). The core is directed by Dr. Mary Bouxsein who is a leading expert in µCT analysis of bone. Guidelines for the use of µCT analysis of rodent bones were published by Dr. Bouxsein and colleagues (PDF).  While we mainly perform µCT analysis of rodent specimens, we are able to work with clients to analyze the microstructure of many other types of specimens. As all scanning is performed on excised specimens, there is no need for additional IRB approvals. Specimens can be scanned in a variety of media (saline, formalin, ETOH), such that specimens can be used for subsequent histologic or other analyses. We also offer mechanical testing and micro-finite element analysis (µFEA) for the assessment of the structural and apparent material properties of bones.

Imaging services that we offer include:

• µCT scanning of ex vivo specimens up to 36 mm in diameter and 80 mm in length
• Trabecular and cortical bone micro-architecture analysis
• Osmium tetroxide staining for the analysis of marrow adiposity via µCT
• Custom µCT scanning and analysis to measure client-defined parameters
• Preparation of 2D and 3D µCT images and movies for publications and presentations(click here to see examples of the types of images that we can create)
• Expert consultation on study design, as well as interpretation of results
• in vivo peripheral dual-energy x-ray absorptiometry (pDXA, PIXImus II) for the measurement of areal bone mineral density (BMD), bone mineral content (BMC) and body composition in mice

Mechanical analysis services that we offer include:

• 3 and 4-point bend testing of long bones (spans from 8mm to 150mm)
• Compression testing (1N to 10 kN)
• Reference-point indentation to assess tissue-level properties
• micro-finite element analysis (µFEA) to model the predicted stiffness and strength of bones

Equipment

• µCT measurements are performed using a µCT40 scanner (SCANCO Medical AG)
• DEXA measurements are performed using a PIXImus II densitometer (GE Medical Systems)
• Bending and compression tests are performed with a BOSE Electroforce 3230 or Instron 8511 servohydraulic testing machine.
• Reference point indentation is performed with a Biodent (Active Life Scientific)

Submitting samples for µCT and mechanical analysis:

Instructions for preparing samples for µCT and mechanical analysis are available on the Protocols page. Please email us at microctcore@partners.org if you have questions about preparing your samples.