Information about various topics discussed at the meeting of orthopaedic group Orthopaedic Research Society in San Francisco, California on February 4-7, 2012. Topics include the study on the calculation of skeletal muscle mass index in elderly patients with acute vertebral fractures, the osteocytic pericellular matrix (PCM) in bone canaliculi and compressive tissue failure. The prevalence of sarcopenia is also tackled.