Search PubMed⌕ Search

Biomedical subjects

R H Edwards

Publications and source records attributed to R H Edwards.

442 records · Page 25Linked to original sources
PubMedDate not supplied

The morphology and morphometry of the normal human tibialis anterior muscle.

The light microscopic appearance of the human tibialis anterior muscle is described based on conchotome biopsy specimens from seven healthy volunteers and 20 patients who presented with myalgia but who had no evidence of neuromuscular disease. The morphometric characteristics of these normal muscles are documented and the similarities and differences between the appearances of the tibialis anterior and other muscles discussed.

Adult↗
PubMedDate not supplied

Investigation of muscle imbalance in the leg in symptomatic forefoot pes cavus: a multidisciplinary study.

The cross-sectional areas of the peroneal and anterior muscle compartments at the same level in the upper leg were measured using magnetic resonance imaging in 41 cases of forefoot pes cavus. The pes cavus group included idiopathic cases and pes cavus associated with Charcot-Marie-Tooth disease, Friedreich's ataxia, cerebral palsy, status postpoliomyelitis, nerve trauma, and spinal cord tethering. Thirty-nine of these cases were symptomatic. The results were compared with studies of 11 normal controls. It was found that in the majority of cases of forefoot cavus, the peroneal compartment was enlarged relative to the anterior compartment when compared with the normal controls. Biopsies of the tibialis anterior and peroneus longus muscles in 18 patients with forefoot pes cavus showed that any relative expansion of the peroneus longus was not due to pseudohypertrophy. Overaction of the peroneus longus in comparison to its antagonist the tibialis anterior is proposed as an important factor in the pathogenesis of the majority of symptomatic cases of forefoot pes cavus.

Adolescent↗
PubMedDate not supplied

Muscular exercise and fatigue.

The development of muscular fatigue during exercise is a common phenomenon, and several forms depend on the precise type of exercise performed. The causes are still not clearly established, although the involvement of electrical and metabolic factors have been demonstrated. Several techniques which allow for the analysis of muscle function in terms of electrical activation and energy metabolism are (a) a needle biopsy of muscle for histochemical and metabolic studies, (b) magnetic resonance spectroscopy for the non-invasive study of muscle energy metabolism and pH, (c) electromyographic analysis of the electrical characteristics of muscle, and (d) percutaneous electrical stimulation of muscle for the force-frequency and relaxation characteristics of muscle. Endurance training increases the capacity to sustain exercise possibly by altering muscle energy metabolism and contractile properties. Fatigue is a self-protective mechanism against the damage of contractile machinery of muscle as, for example, with the development of rigor, which occurs if the energy stores are depleted. To illustrate the roles of energy supply and electrical properties in muscle in fatigue, the 'catastrophe theory' used in engineering has been applied. This may explain abrupt changes of function of individual muscle cells, while for the muscle as a whole, fatigue may be manifested as a more gradual loss of force.

Electric Stimulation↗
PubMedDate not supplied

Portable maximum respiratory pressure measurement--a comparison with laboratory techniques.

We have evaluated a new, hand-held, electronic device to measure maximal respiratory pressures, and compared its performance in normal subjects against two pre-existing methods. This new device produces accurate, reproducible results and has the advantages of easy use and portability, which allow it to be used at the patient's bedside, outpatient clinic or pulmonary function laboratory.

Adult↗