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Date of Award
Doctor of Philosophy (PhD)
People with diabetes mellitus and peripheral neuropathy (DMPN) have midfoot and ankle musculoskeletal problems, including limited joint mobility and weakness and atrophy of foot intrinsic and calf muscles. Impaired foot structures and function could lead to midfoot and ankle movement dysfunction, measured by a heel rise task. A repeated movement dysfunction during weightbearing tasks (e.g., heel rise, walking) could cause excessive stress on the plantar tissue, which is a leading cause of plantar ulceration in people with DMPN. Understanding heel rise performance and the underlying mechanisms could help prevent the sequence of events associated with plantar ulcer development in people with DMPN.
In Chapter 2, we examined the effects of DMPN, limited midfoot and ankle joint mobility, and weightbearing on midfoot and ankle sagittal movements during heel rise; and characterized the midfoot and ankle position and movement trajectories of heel rise. Our results showed that midfoot and ankle plantarflexion were reduced during heel rise and non-weightbearing plantarflexion tasks in people with DMPN. Reduced midfoot and ankle plantarflexion in non-weightbearing suggests that people with DMPN had limited joint mobility. However, peak unilateral (i.e., single-limb) and bilateral (i.e., double-limb) heel rise was less than the full available plantarflexion range of motion measured in non-weightbearing, indicating that limited joint mobility did not limit heel rise performance. A higher percentage of people with DMPN were in midfoot and ankle dorsiflexion at peak unilateral heel rise compared to the non-DMPN controls, but the position and movement trajectories were restored with bilateral heel rise, a reduction in weightbearing load. Clinicians should consider appropriate resistance when treating midfoot and ankle movement dysfunctions since midfoot and ankle plantarflexion magnitude, position, and movement trajectory during unilateral heel rise were improved by reducing the amount of weightbearing.
In Chapter 3, we determined the factors associated with midfoot angle at peak heel rise. We found that body mass index and maximum available midfoot plantarflexion range of motion were significant factors that accounted for 41.4% of variance of the midfoot angle at peak heel rise, while age and intrinsic foot muscle volume were not significant predictors. Weight and midfoot plantarflexion range of motion are potentially modifiable, which should be considered when health care professionals prescribe foot exercises to improve midfoot performance during weightbearing tasks in people with DMPN.
In Chapter 4, we examined the relationship of heel rise performance to gait and characterized the trajectory of midfoot and ankle motion of unilateral heel rise and gait in people with DMPN. People with DMPN who failed to plantarflex the midfoot and ankle during heel rise had difficulty plantarflexing the midfoot and ankle during gait. Clinicians could use the heel rise task to identify midfoot and ankle dysfunction associated with gait in people with DMPN.
The results of this dissertation support the use of plantarflexion tasks of unilateral, bilateral, and non-weightbearing to help identify midfoot and ankle movement dysfunction in people with DMPN. Weight management and increasing joint motion might improve midfoot and ankle movements during weightbearing tasks in people with DMPN. Furthermore, clinicians could also benefit by utilizing a simple heel rise task as a surrogate measure for evaluating midfoot and ankle movement dysfunction during gait.
Chair and Committee
Michael J. Mueller Mary Hastings
Gammon M. Earhart, Catherine E. Lang, Susan L. Stark,
Jeong, Hyo Jung, "Midfoot and Ankle Movement Dysfunction in People with Diabetes Mellitus and Peripheral Neuropathy" (2021). Arts & Sciences Electronic Theses and Dissertations. 2369.
Available for download on Tuesday, December 28, 2021