Musculoskeletal System Commons^™

Effects Of Neurotrophic Factors On Osteoblast Growth And Differentiation, Colleen M. Moran

Loma Linda University Electronic Theses, Dissertations & Projects

Recent evidence suggests that bone metabolism may be influenced by the innervation of skeletal tissues. Innervation of skeletal tissues might directly influence bone volume by the release or secretion of osteogenic growth factors in the form of neuropeptides. These neuropeptides could act locally on osteoblasts to increase bone formation and/or mineralization. Since calcitonin gene-related peptide (CGRP) and Substance P (SP) are the most abundant neuropeptides present in sensory nerves in bone, the current studies were intended to test the hypothesis that these two neuropeptides may have direct effects on osteoblast growth, differentiation, and mineralization. Replicate cultures of murine calvarial osteoblasts …

Neurophysiologic Bases For Abnormal Muscle Coactivation Patterns In Hemiparetic Stroke, Julius P.A. Dewald

Loma Linda University Electronic Theses, Dissertations & Projects

To study disturbed muscle activation patterns in hemiparetic stroke, the EMG activity in spastic-paretic and contralateral elbow muscles of 10 stroke subjects were compared during graded directionally varying voluntary isometric contractions. We observed significant shifts in the peak EMG angle and increases in the angular range of EMG activity in the impaired upper limb. Furthermore, we observed stereotypic coactivation of many muscles acting at the same joint or at different joints across all subjects.

The effect of elbow angle changes on muscle coactivation patterns was studied by examining isometric torque-angle relations under passive and active conditions in 8 stroke subjects. …

The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga

Loma Linda University Electronic Theses, Dissertations & Projects

A deleterious effect of spaceflight on human health is the loss of bone associated with the prolonged lack of gravitational stress on the skeleton. A potential for bone loss is indicated by the hypercalciuria and decreased heel bone density determined in Skylab astronauts. Histological studies of juvenile laboratory rats in actual spaceflight and in simulation models document a suppression of bone formation with little alteration of bone resorption. The mechanism for net bone loss needs to be defined in order to develop measures for its prevention or correction.

Skeletal growth factors, which may mediate coupling and locally regulate bone volume …

Cineradiography Of The Temporomandibular Joint : A Research Entity And Diagnostic Modality, L. Albert Lewis

Loma Linda University Electronic Theses, Dissertations & Projects

Readily accessible equipment as utilized for cineangiography has been demonstrated to be useful in producing dynamic studies of the temporomandibular joint.

The reproducible studies have been obtained without adaptation of equipment. Methods used in this project were based on principles which have been advocated for the past thirty years for static radiographs of the temporomandibular joints.

Studies were made of a variety of subjects varying in size and joint integrity. Diagnostic views were obtained on all subjects showing normal osseous joint structures and typical joint function via the use of motion picture records. Changes in osseous joint structures were readily …

Masseter And Temporal Muscle Adaptability To Interproximal Contact Disruption : An Electromyographic Study, Robert E. French

Loma Linda University Electronic Theses, Dissertations & Projects

In this study an attempt was made to determine the amount of interproximal contact disruption necessary to initiate an electromyographically discernable deviation in the masticatory musculature. Ten adult subjects with adjudged normal occlusions were used. An additional study was under taken to determine the time necessary for the right and left temporal and masseter muscles to accommodate this disruption. Myographic recordings were taken of the subjects while closing firmly in centric occlusion and chewing Dentyne gum first on the right side, then on the left.

Contact disruption was accomplished with a metal shim of .003 inch thickness and later in …

Electromyographic Analysis Of The Temporal And Masseter Muscles During The Para-Retentional Period In Orthodontic Patients, Thomas L. Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

This study was initiated to compare electromyographically the activity of the masseter and temporal muscles during the early retentional period in orthodontic patients. Electromyographic recordings were taken at the following times: (1) before typical edgewise appliance was removed, (2) at time of retainer insertion, (3) after eight to twelve weeks of retainer wearing, and (4) one day following occlusal equilibration. Electromyograms from the orthodontic group of subjects were compared with electromyograms from a group of subjects with normal occlusion, and a group of subjects with untreated Class II, Division 1 malocclusions. There was a total of thirteen subjects studied: five …