Biomedical subjects

S Gum

Publications and source records attributed to S Gum.

3 recordsLinked to original sources

PubMed1998

Biochemistry and biomechanics of healing tendon: Part I. Effects of rigid plaster casts and functional casts.

PURPOSE: Traditional treatment of surgically repaired Achilles tendons includes complete immobilization of the joint in rigid casts for 6 to 8 wk. We tested the use of functional polyurethane casts as an alternative to rigid plaster casts after experimental tenotomy and repair of the rabbit Achilles tendon. METHODS: After repair the limbs of 15 experimental rabbits were immobilized in a functional polyurethane cast for 15 d, while those of 14 controls were immobilized in traditional rigid plaster casts for the same period. RESULTS: Functional casting resulted in a 60% increase in total collagen in the neotendon compared with that in rigid casting (P < 0.05). Mature collagen cross-links declined 8% in the tendons with functional casts. The biomechanical parameters of the tendons changed with functional casting, showing a 20% increase in maximum load and 21% increase in maximum stress. CONCLUSIONS: These changes were noted without any cases of tendon re-rupture in either type of cast. Thus, functional casting following surgery of Achilles tendons appears to improve healing without significant risks of re-rupture.

Achilles Tendon↗

PubMed1998

Biochemistry and biomechanics of healing tendon: Part II. Effects of combined laser therapy and electrical stimulation.

PURPOSE: In previous studies we demonstrated that early mechanical loading and laser photo-stimulation independently promoted tendon healing. Thus, we tested the hypothesis that a combination of laser phototherapy and mechanical load would further accelerate healing of experimentally tenotomized and repaired rabbit Achilles tendons. METHODS: Following surgical tenotomy and repair, the tendons of experimental and control rabbits were immobilized in polyurethane casts for 5 d. The repaired tendons of experimental rabbits received mechanical load via electrical stimulation-induced contraction of the triceps surae for 5 d. In addition, experimental tendons were treated with daily doses of 1 J.cm-2 low intensity helium-neon laser throughout the 14-d experimental period. RESULTS: The combination of laser photostimulation and mechanical load increased the maximal stress, maximal strain, and Young's modulus of elasticity of the tendons 30, 13, and 33%, respectively. However, MANOVA revealed no statistically significant differences in these biomechanical indices of repair of control and experimental tendons. Biochemical assays showed a 32% increase in collagen levels (P < 0.05) and an 11% decrease in mature cross-links in experimental tendons compared with that in controls (P > 0.05). Electron microscopy and computer morphometry revealed no significant differences in the morphometry of the collagen fibers and no visible differences in the ultrastructure of cellular and matrical components of control and experimental tendons. CONCLUSIONS: These findings indicate that the combination of laser photostimulation and early mechanical loading of tendons increased collagen production, with marginal biomechanical effects on repaired tendons.

Achilles Tendon↗

PubMed1995

The Clinical Anger Scale: preliminary reliability and validity.

This article reports preliminary evidence for the development and validation of the Clinical Anger Scale (CAS), an objective self-report instrument designed to measure the syndrome of clinical anger. Factor analysis of the CAS confirmed a unidimensional item structure; reliability analyses also demonstrated adequate internal consistency and test-retest stability for the CAS; other results indicated that the CAS was unrelated to social desirability influences. Additional findings indicated that clinical anger was associated positively with several anger-related concepts (e.g., trait anger, state anger, anger-in, anger-out, anger-control) and that the CAS was related in predictable ways to people's psychopathological symptoms, personality traits, and early family environments. Implications for future research and therapeutic assessment with the Clinical Anger Scale are discussed.

Acting Out↗