PubMed Health⌕ Search

Biomedical subjects

C W Jansen

Publications and source records attributed to C W Jansen.

8 recordsLinked to original sources
PubMed1997

Effect of work glove and type of muscle action on grip fatigue.

Fatigue plays a major role in limiting work performance. The objectives of this study were: (1) to determine the effect of wearing a work glove on handgrip fatigue; (2) to compare the effect of a sustained grip contraction of concentric versus eccentric nature, named in this study isometric and eccentric; and (3) to determine if there is a relationship between physiological muscle performance and subjective perceptional fatigue during isometric and eccentric gripping. The study had 2 x 2 repeated measures design. The two factors were: (1) glove condition (glove, no glove); and (2) type of contraction (eccentric and isometric). The measurements taken were: (1) time to limit of endurance (Tlim); (2) rate of perceived effort (RPE); (3) mean power frequency (MPF) derived from the electromyogram (EMG); and (4) the fatigue objective-subjective relationship (FOSR, which is the correlation coefficient between RPE and MPF). Twenty-one normal subjects maintained a handgrip of 60% of their maximal effort until exhaustion for each of the four conditions. During each trial EMG values were recorded every 5 s and RPE values were recorded every 10 s. The RPE was recorded as a subjective value selected from a 10-point Borg scale. The results showed that Tlim was greater for the no glove condition (p < 0.0005) and for the eccentric muscle action (p < 0.05). The FOSR was greatest for the glove condition (p < 0.03) and for the isometric muscle action (p < 0.013). The MPF decline showed no significant difference for any condition. These data indicate that glove condition and type of handgrip contraction have an effect on physiological fatigue and subjective perception of fatigue.

Adult↗
PubMed1993

Measurement of range of motion of the finger after flexor tendon repair in zone II of the hand.

The purpose of this study was to compare classification systems of active range of motion of the finger after flexor tendon surgery in zone II of the hand. Active range of motion of 20 fingers (16 subjects) was classified according to five systems. Agreement between the systems was only fair. Strickland's original system and the Louisville system rated the results most strictly, followed by Strickland's adjusted system. Buck-Gramcko's systems (in centimeters and degrees) rated the results least strictly. Strickland's systems conformed most closely to measurement principles. This article concludes that at this time Strickland's original classification system is preferable for scientific and clinical purposes. However, additional research is needed to evaluate reliability of the measurement, the variability of the scaling factor of 175 degrees, the sensitivity of the measurement, and the validity of the measurement with regard to functional use of the finger and gliding of the repaired tendon.

Adult↗
PubMed1993

[Prefabricated tympanic prosthesis].

Total and subtotal perforations of the tympanic membrane cause problems. Adhesions and poor hearing results are the outcome when just the stapes or the footplate remain intact. Reinforcement of the transplant using cartilage and plastic sheeting were not successful in the long run. The tympano-wire prosthesis with its concave form prevents the above mentioned disadvantages. Short interpositioning is to prefer in order to prevent impedance.

Humans↗
PubMed1985

Functional repair of the eustachian tube.

Endoscopy of the eustachian tube provides a new diagnostic potential for many problems of middle ear disease. The flexible fiberoptic system works from the nasopharynx as well as from the tympanic orifice, depending on the indications. It must be realized, however, that this is just the beginning of a new technique. Eustachian tube surgery plays a special role in connection with the new fiberoptic system. Preservation of the posterior bony canal wall and of the mucosal lining of the eustachian tube are the essentials of this modern approach.

Ear Diseases↗
PubMedDate not supplied

Effects of fingernail length on finger and hand performance.

The purpose of this study was to investigate effects of fingernail length on active range of motion (AROM) of the fingers, speed of finger manipulation, number of words typed, and grip strength. Fifteen normal women (mean age, 30 years) performed measurements under four conditions--with no attached fingernails and with fingernails extending 2, 1, and 0.5 cm beyond the tip of the finger. Analyses of variance showed that: 1) with fingernails of all extended lengths, grip strength measured on the first setting of the Jamar hand dynamometer decreased; 2) with fingernails 1 and 2 cm in length, AROM, grip strength on the second dynamometer setting, and finger manipulation decreased; and 3) with fingernails 2 cm in length, typing speed decreased (p < 0.05). Long fingernails limit flexion of the finger joints, particularly the metacarpophalangeal joints. Lack of finger flexion will limit excursion of long flexors and extensors in patients. It is recommended that patients cut their fingernails to a length of 0.5 cm to achieve optimal functional outcomes.

Activities of Daily Living↗
PubMedDate not supplied

The effect of use of a wrist orthosis during functional activities on surface electromyography of the wrist extensors in normal subjects.

Wrist orthoses are advocated for patients with lateral epicondylitis on the assumption that use of the orthosis decreases muscle activity of the wrist extensors during activities. The purpose of this study was to compare the amount of electrical activity, root mean square (RMS) calculated from surface EMG recorded over the wrist extensors, during activities when applying four conditions of wrist orthoses: dorsal; volar; semicircular; and no orthosis. Thirteen normal subjects (mean age 27.7 years) performed three lifting and two gripping tasks, repeated on three consecutive days under four orthotic conditions. Measured were RMS and maximum voluntary grip strength. Repeated measures ANOVA's indicated a significant decrease of RMS using the semicircular design during lifting (p < .0005). Grip strength decreased significantly using all three orthotic designs, but RMS recorded during gripping did not. It was concluded that application of a wrist orthosis reduces electrical activity of the wrist extensors less than anticipated and only during lifting.

Adult↗
PubMedDate not supplied

Case reports and case studies: a discussion of theory and methodology in pocket format.

Issues of the theory and methodology of case reports and case studies have been presented. Examples of applications of techniques used in the rehabilitation of the upper extremity conclude this report in pocket format on the theory and methodology of case reports and case studies. Case reports and studies enhance our knowledge about practice in ways that are unique to each case, which are not possible when investigations are performed through group comparison. Case inquiries help us share our practice, sharpen our theoretical reasoning, develop our good habits of applying reliable and valid measurements, and above all help us explore and discuss our treatments.

Communication↗