Date of Award


Document Type


Degree Name

Medical Doctor (MD)

First Advisor

Jonathan Grauer


Study Design: Biomechanical studies of the range of motion (ROM) of the spine in asymptomatic subjects. Objective: To define a normative data set for functional ROM of the cervical and lumbar spine and to evaluate how several common cervical and lumbar orthoses impact full, active and functional ROM of the spine. Summary of Background Data: Spinal ROM is critical to normal function in daily tasks. Previous studies have focused primarily on the maximum ROM of the spine (full, active ROM). Functional ROM, the motion used while performing activities of daily living (ADLs), is typically much less than full, active ROM and may be a more clinically useful measure. However, there have been few studies that have evaluated functional ROM in asymptomatic subjects or in subjects wearing braces. Methods: Electrogoniometers were attached to the subjects and used to continuously record the full, active and functional cervical and lumbar ROM of 60 asymptomatic subjects during 15 ADLs. Additionally, 10 additional subjects were selected to evaluate how two cervical orthoses (a soft and rigid neck collar) and 3 lumbar orthoses (a soft corset, a semi-rigid off-the-shelf lumbosacral orthosis [LSO], and a custom molded LSO) affected cervical and lumbar ROM. Results: Normative lumbar and cervical functional ROM was significantly less than full, active ROM. Cervical and lumbar orthoses demonstrate varying degrees of restriction of full, active ROM. However, they are capable of restricting functional ROM at levels below what is possible by physically restraining head motion indicating that during ADLs spinal orthoses act as proprioceptive aids to guide patients to restrict motion further than the mechanical constraint they provide. Conclusions: These studies are some of the first to evaluate functional ROM in the spine. The normative data provides a picture of how much spinal motion is needed during ADLs. The bracing studies demonstrate how orthoses can act as proprioceptive aids to encourage the patient to self limit their own motion. It is possible that in certain, non-traumatic, settings (such a post-operatively when internal fixation is generally utilized), less rigid braces may be appropriately considered to minimize patient discomfort, increase wear compliance, and decrease durable medical equipment costs.


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