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Biomedical subjects

D Antonelli

Publications and source records attributed to D Antonelli.

81 records · Page 5Linked to original sources

Metabolic energy cost of unrestrained walking.

Physiologic factors of metabolic energy cost as well as selected mechanical characteristics of gait are described in a group of 40 presumably normal men and women between the ages of 20 and 60 years. Special emphasis was placed on unrestrained (free cadence) walking to provide a reliable baseline for comparison to persons with physical gait impairments. Velocity of walking was the most important factor in determining oxygen uptake and was independent of age or sex. An empirical equation was established relating oxygen uptake to the speed of walking. The average velocity for men in unrestrained walking trials was 89 meters per minute; for women 74 meters per minute. These differences were related to the greater stride length in men. The average cadence selected by both sexes was 116 steps per minute. None of these factors was age dependent. Of the physiologic measures only systolic blood pressure was age dependent predictably rising with age. The mean heart rate was 103 beats per minute and did not vary significantly between men and women. The mean respiratory rate was 19 per minute; the mean respiratory quotient, 0.85, neither being age or sex dependent. Oxygen uptake values averaged 12.95 ml/kg-min for the population studied and again were neither age nor sex dependent.

Adult↗

Energy cost of walking of amputees: the influence of level of amputation.

A comparison of selected gait parameters and the energy cost of prosthetic walking was made in seventy patients with unilateral traumatic and vascular amputations. Amputations above the knee, below the knee, and at the Syme's level were compared in both groups of amputees, and a control group of forty normal subjects also studied. In both groups of amputees performance was significantly better the lower the level of the amputation. When preservation of function is the chief concern, amputation should be performed at the lowest possible level.

Adult↗

Electromyography before and after surgery for hip deformity in children with cerebral palsy. A comparison of clinical and electromyographic findings.

Twenty-three ambulatory children with spastic diplegic cerebral palsy were evaluated clinically and by electromyography before and after hip-muscle surgery. The stretch tests originally designed to distinguish specific muscle tightness and spasticity were found to be non-specific when tested by electromyography. Ambulatory electromyograms using needle electrodes and telemetry generally showed decreased activity in the released muscles and, on occasion, changes in activity in muscles not operated on. These unanticipated changes after release may explain some of the unpredictability of results of such procedures in cerebral palsy.

Adolescent↗

Analysis of knee-joint forces during flexed-knee stance.

Using an instrumented cadaver lower extremity, the forces in the quadriceps, patella, and tibia during flexed-knee stance were measured and the calculated and experimental data were found to correlate with an average discrepancy of 6 per cent. The quadriceps force required to stabilize the knee was 75 per cent of the load on the femoral head at 15 degrees of knee flexion, 210 per cent at 30 degrees, and 410 per cent at 60 degrees. Stresses at the tibiofemoral and patellofemoral joint surfaces increased in similar fashion. The quadriceps force was equivalent to 20 per cent of average maximum quadriceps strength at 15 degrees and to 50 per cent at 30 degrees, as determined from torque tests on five normal subjects.

Biomechanical Phenomena↗

Fine wire electromyography analysis of muscles of the shoulder during swimming.

Fine wire EMG of the shoulder was performed on 11 swimmers; 5 performed during dry land studies and 7 during aquatic studies. One individual underwent both studies. A cinematographic analysis was synchronized with the EMG data to determine what muscles were firing at each phase of the swim stroke. Eight muscles were studied: biceps, subscapularis, latissimus dorsi, pectoralis major, supraspinatus, infraspinatus, serratus anterior, and deltoid. Three strokes were analyzed: freestyle, breaststroke, and butterfly. The freestyle and butterfly are frequently associated with impingement type syndromes in swimmers. It was determined that the supraspinatus, infraspinatus, middle deltoid, and serratus anterior were predominately recovery phase muscles. The latissimus dorsi and pectoralis major were predominately pull-through phase muscles. The biceps had mixed inconsistent activity during both phases. From dry land quantifications of the EMG signal it was determined that the serratus anterior functions near maximal muscle test during each stroke, and theoretically may fatigue with repetition. It is hoped that a training program aimed to strengthen the scapular rotators may help alleviate impingement syndrome in swimmers.

Adult↗

[The Hartmann procedure in colorectal emergencies. Report of 76 cases].

The Hartmann procedure has, in emergency colo-rectal surgery, many implications. The decision is based on clinical, radiological, instrumental and pathological findings. The authors report the results of 76 Hartmann's procedures performed between 1986 and 1995 and compare their results with those found in the current medical literature on the topic. In particular, they draw attention to an increased use of this procedures in colo-rectal emergencies; the morbility and mortality rates confirm the severity of the clinical cases that can be treated with this operation. To improve results the authors propose a therapeutic plan that uses a score for stratification of the risk (MPI, APA-CHE II, SSI, Hinchey); so the surgeon can choose the best surgical operation. Finally, the authors underline the importance of the principles of oncology surgery in colo-rectal cancer.

Aged↗

[Intrahepatic lithiasis. Apropos of 36 cases of "regional" intraheptic lithiasis].

Out of 2,700 operations for cholelithiasis and its sequelae (1960-1976), 36 cases (1.3%) of intrahepatic lithiasis (i.l.), namely proximal to the origin of the common hepatic, were observed. The prime objective of treatment namely removal of calculi, was achieved indirectly (hepatocholedochus and/or papilla) in 84% of cases, directly (hilar) in 16%. The second objective, that of ensuring optimal bilio-enteric drainage, was achieved by papillostomy or hepaticojejunostomy depending on the lumen of the bile way (respectively less or more than 2 cm.). Operative mortality was nil, while long-term results have proved poor in 9.6% of cases. The i.l. problematic is dealt with in detail on the basis of this series.

Adolescent↗