UBC Theses and Dissertations
Upper limb bone health : cadaveric, imaging and clinical studies with special emphasis on peripheral quantitative computed tomography Ashe, Maureen Celeste
Introduction: Osteoporotic fractures are a major health care problem. A radial fracture is an important risk factor for osteoporosis that should initiate the assessment of bone health. Purpose: 1) To validate pQCT measures of bone in aged cadaveric radii. 2) To examine side-side differences in radial bone variables after disuse. 3) To test a novel intervention for secondary prevention of osteoporosis after an index radial fracture. Methods: Study Design: Part 1: Parts 1A and 1B are descriptive cadaveric studies. Part 2: Cross-sectional observational studies of bone response to disuse; Part 3: Part 3A is a 6-month intervention of secondary prevention of osteoporosis following a fragility fracture. Part 3B uses a questionnaire to ascertain barriers to investigation after fracture. Participants: Part 1: Cadaveric specimens from women (73 to 88 years) for Parts 1A and 1B. Part 2A: Women (52-87 years) who sustained a distal radius fracture and Part 2B: women and men (52 to 79 years) who had suffered a stroke. Part 3A: Women and men (50-90 years) with a fragility fracture; and Part 3B: physicians in British Columbia. Results: Part 1: With different pQCT acquisition-analysis protocols, total bone area varied by 3-34%; cortical area varied by 3-30% and total content by 6-45% from a criterion standard. Total bone content of the distal radius explained between 74 and 81% of bone strength. Part 2: There was a significant decrease in bone strength in participants who had upper limb disuse because of stroke or fracture. Part 3: A patient and physician intervention improved bone health investigation rate by a factor of 3.1 times (RR) after fragility fracture. BC doctors reported few barriers to investigating osteoporosis. Summary: Peripheral QCT acquisition and analysis protocols significantly influenced outcome variables. Patients do not have "normal" bone strength after fracture or stroke. In particular, there is an increased risk for non-dominant radial fractures to have lower bone strength and be associated with poorer limb function, compared with a dominant radial fracture. Physicians report no barriers to investigation after a fragility radial fracture and a systematic intervention may best address secondary prevention of osteoporosis.
Item Citations and Data