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T Oberg

Publications and source records attributed to T Oberg.

At least 37 records · Page 2Linked to original sources

Electromyogram mean power frequency in non-fatigued trapezius muscle.

In this study we have examined the variation of mean power frequency (MPF) in the electromyogram (EMG) from the non-fatigued trapezius muscle, with different external hand loads, in different shoulder joint positions, different torques and different planes of movement. The study was limited to the functional range of movement in the shoulder joint. It was performed on 19 healthy subjects. Surface EMG was recorded, analysed by means of a computer programme and examined by regression analysis. Normalized MPF values were calculated by dividing the MPF by the individual average MPF for all positions and loads. The results indicated no major variation in normalized MPF. The largest systematic variation of normalized MPF, +/- 8%, was related to joint angle. We have concluded that the MPF value obtained initially can be used within the functional range of movement to calculate the relative decrease in MPF as a result of muscle fatigue, and that the decrease is significant if it exceeds 8% of the initial value.

Adult↗

Thickness of the soft tissue layers and the articular disk in the temporomandibular joint.

Out of 115 right temporomandibular joints from Swedish subjects aged 1 day to 93 years, 48 joints without any gross sign of arthrosis or deviation in form were examined histologically. The joint components were cut sagittaly, each into four parts. Histological sections were made of the condyle, the temporal component and of the articular disk. The total thickness of the soft tissue layers was measured in decalcified sections, cut from the medio-central and lateral parts of the condyle and the temporal component and from the medial, medio-central, latero-central and lateral regions of the disk. In the medio-central sections from the condyle and temporal component the thickness of the fibrous connective tissue layer i.e. the surface layer was also registered. The soft tissue layers were thickest in the condyle superiorly, about 0.4-0.5 mm, in the temporal component on the postero-inferior slope of the articular tubercle, about 0.5 mm, and in the disk posteriorly about 2.9 mm. In the roof of the fossa it was only 0.1 mm. The soft tissue layers on the condyle as well as the disk were thinner laterally while the corresponding tissue in the temporal component was thicker laterally. The thickness of the soft tissue layers seem to reflect the growth and functional load to which the joint is exposed.

Adolescent↗

Arthrosis and deviation in form in the temporomandibular joint. A macroscopic study on a human autopsy material.

The right TMJ from 115 individuals, aged 1 day--93 years, were examined macroscopically regarding the occurrence of deviation in form and arthrosis in the three articulating joint components. The changes were classified according to extent. In addition, the depth of the arthrotic lesions was determined. Nearly half (48 of 102) of the adult TMJs revealed some form of change. No changes in the joint surfaces were noted from individuals under 20 years of age. Deviations in form occurred in 45 of the 48 affected joints and arthrosis in 24. The deviations in form were most common in the condyle while arthrotic lesions were noted mainly in the disk and temporal component of the joint. The changes were usually local in nature and located in the lateral one-third of the joint.

Adolescent↗

Degenerative disease in the temporomandibular, metatarsophalangeal and sternoclavicular joints. An autopsy study.

The right temporomandibular, sternoclavicular and first metatarsophalangeal joints were removed post mortem from 39 subjects. The surfaces of the various parts of the joints were examined and evaluated according to a grading system. Repeated evaluation of the joints showed a good reproducibility of the grading system. Of the 33 temporomandibular joints, 12 showed deviations in shape. Degenerative disease was uncommon and seen in only 3 joints. The total "score for degeneration" showed only a weak correlation with age (r = 0.28, rs = 0.08). Degenerative disease was common in the 35 sternoclavicular joints. All joints except 7 showed degenerative changes. A moderate correlation was found between age and the score for degeneration (r = 0.58). Of the 39 metatarsophalangeal joints only 5 were allotted no points of degeneration. A moderate correlation was found between age and score for degeneration (r = 0.61). No significant differences of degeneration were found between sexes. The coefficient of correlation between the score for degenerative disease of the temporomandibular joint and the degeneration score for the sternoclavicular joint and the toe-joint were r = 0.22 (rs = 0.16) and r = 0.46 (rs = 0.44), respectively. The significant association of degenerative disease found between the toe-joint and the sternoclavicular joint (r = 0.54, rs = 0.54) was reduced (to r = 0.29) when age-dependence was excluded. The degenerative changes described in this material are probably mostly due to local factors.

Adolescent↗

The effect of an occlusal interference on the masticatory system. An experimental investigation.

An experimental short term study on the effect of an occlusal interference on the path of closure of the mandible was carried out on 8 persons. The interference consisted of a gold inlay placed unilaterally in one of the mandibular first molars. Clinical and electromyographic studies revealed functional disturbances or pain in all subjects. The masticatory musculature was tender to palpation and showed coordinational disturbances; the TMJ showed tenderness to palpation, clicking and irregular movements and the interfering teeth periodontal tenderness.

Adult↗