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Biomedical subjects

K T Ragnarsson

Publications and source records attributed to K T Ragnarsson.

31 records · Page 2Linked to original sources
PubMed1988

Physiologic effects of functional electrical stimulation-induced exercises in spinal cord-injured individuals.

Spinal cord injury (SCI) results in multiple degenerative changes that may in part be related to physical inactivity. There are indications that some of these changes may be reversed by exercise and fitness training. Computerized functional electrical stimulation (FES) allows active exercise of limbs paralyzed by upper motor neuron lesions. Thirty SCI subjects safely participated in an FES-induced exercise program for lower extremity strengthening and endurance training. Increased strength, endurance, and bulk of stimulated muscles were noted. The subjects were able to perform a greater amount of work on a lower extremity ergometer, both per unit of time and per length of time, indicating a training effect. A multistage stress test showed evidence that the subjects had increased their aerobic metabolism during the training program. Twitch time tests showed slowing of muscle contraction, and computed tomography showed increased muscle density.

Adolescent↗
PubMed1988

Clinical evaluation of computerized functional electrical stimulation after spinal cord injury: a multicenter pilot study.

This study investigated the safety and effects of computerized functional electrical stimulation (FES) on spinal cord injured individuals. Nineteen subjects two to ten years postinjury, with clinically complete motor and sensory lesions between C4 and T10, participated. All subjects met the specific selection criteria. None had received lower extremity electrical stimulation before. In phase I, subjects received surface electrical stimulation to the quadriceps muscle bilaterally for resistive knee extension 3 times a week for four weeks. The resistance and number of completed lifts was recorded daily. In phase II, 36 sessions provided sequential surface electrical stimulation to the quadriceps, hamstrings, and gluteus muscles bilaterally in order for subjects to pedal a lower extremity ergometer with resistance varied depending on completed run time. For each session, heart rate, blood pressure, temperature, and work performance were recorded. Tests done before and after the training program included fasting blood chemistries, 24-hour urinalysis, arm-crank ergometer stress testing, and midthigh girth measurement. Results indicate that this form of FES is safe, that quadriceps strength and endurance is increased, that endurance for ergometer pedaling is increased, and that there may be a training effect as more work is done at a similar heart rate and systolic blood pressure and as muscle bulk is increased. The FES effect on cardiovascular conditioning and general health requires further research to precisely determine its benefits.

Adult↗
PubMed1986

Visually displayed EMG feedback: single case studies of hemiplegic upper extremity rehabilitation.

The efficacy of visually displayed EMG feedback in treating hemiplegic upper limb motor disorders was investigated in 5 patients (0.5-4 years poststroke). A single case experimental method "multiple-baseline across target behaviors" was used to compare performance during the feedback phase to that occurring in the monitored baseline phase. The nonfeedback baseline phase was followed by the staggered introduction of audiovisual feedback for each of the targeted pairs of muscles. EMG feedback obtained from muscle pairs (shoulder: anterior deltoid and upper trapezius; elbow: brachial triceps and biceps; digits: extensor digitorum communis and digit flexors) was displayed as two distinct waveforms on a videomonitor during therapy. Nonfeedback assessment of each of the three pairs was performed during each session. The effects of feedback were not uniformly distributed. Elbow control responded best, and statistical tests confirmed the effects of intervention observed clinically in all 5 patients. Clinical improvements in shoulder flexion were observed in 4 patients but could be statistically attributed to EMG gains in just 1. Improvement in finger extension observed clinically in 3 patients was statistically attributable to EMG gains in 2. All patients regained control of at least one target activity. EMG gains were accompanied by increases in active range of motion and by varying functional improvement. Marked functional gains in 3 patients were obtained with recovery of finger control.

Adult↗
PubMed1985

Sudden quadriplegia after a minor trauma. The role of preexisting spinal stenosis.

Three patients are described who became quadriplegic after a minor trauma to the spine without suffering a spinal fracture dislocation. Radiologic investigation revealed marked stenosis of the spinal canal, due to developmental stenosis with superimposed degenerative changes in two patients, and calcification of posterior longitudinal ligament of the spine in one. Two patients recovered almost completely with conservative measures. The spinal cord may be able to tolerate slowly increasing mechanical pressure for many years and conform to the shape of the spinal canal without causing any neurological symptoms. However, when stenosis is severe, any additional pressure, for example, swelling and edema from trauma, may cause a neurologic catastrophe.

Aged↗
PubMed1985

Deep venous thrombosis: diagnosis in spinal cord injured patients.

Because the acute spinal cord injured patient is at high risk for the development of deep venous thrombosis (DVT), accurate diagnosis is critical. Clinical evaluation is unreliable 50% of the time, however, and the two highly accurate diagnostic procedures--venography and 125I-labelled fibrinogen scanning--are invasive and present serious drawbacks. The literature concerning the effectiveness of the two most widely used noninvasive diagnostic alternatives (Doppler ultrasound and venous occlusion plethysmography [VOP]) is equivocal. In our systematic evaluation of a series of 21 patients, using clinical examination, Doppler ultrasound and VOP, all patients who developed DVT were identified by all three methods. Overall accuracy, sensitivity and specificity were 100%.

Adolescent↗
PubMed1985

Serum albumin as a predictor of course and outcome on a rehabilitation service.

To determine the effect of nutritional status on the medical course and rehabilitation outcome of patients on an adult rehabilitation service, serum albumin (SA) and total lymphocyte count (TLC) were prospectively studied on 36 patients. Readings were taken on admission (T-1), at which time a Barthel Index Mobility Goal (BIMG) was assigned, and again 4 to 8 weeks after admission (T-2). A Barthel Index Mobility Score (BIMS) was assigned at discharge. Rehabilitation program restrictions due to medical complications correlated negatively with both the SA level at T1 (r = -.328, p less than 0.05) and at T2 (r = -.523, p less than 0.01). The SA level at T2 correlated positively with the BIMS:BIMG ratio (r = .416, p less than 0.05) at discharge, suggesting that SA levels may predict patient mobility outcome.

Adolescent↗
PubMed1984

Current trends in stabilizing high thoracic and thoracolumbar spinal fractures.

Studying treatment data for 1,385 patients with traumatic paraplegia registered with the National Spinal Cord Injury Data Research Center during 1973-1979, we investigated: (1) current treatment trends; (2) continuity or change in such trends; (3) trend implications; and (4) whether current practices reflect the controversy in the literature. The data showed little change in the proportion of patients treated surgically, but statistically significant changes in the procedures, especially as related to Harrington rod instrumentation, which increased dramatically both with bony fusion (from none to 24.4%) and in the triple procedure, which adds laminectomy (from 6.1% to 23.2%). These changes have clearly improved health care, as the two predominant surgical treatments were associated with the shortest hospital stays in both the acute and rehabilitation settings.

Fractures, Bone↗
PubMed1981

Head-up tilt effect on glomerular filtration rate, renal plasma flow, and mean arterial pressure in spinal man.

Changes in glomerular filtration rate (GRF), renal plasma flow (RPF), and mean arterial pressure (MAP) were measured in subjects tested in supine and head-up tilt positions with various levels of spinal cord lesion and thus with different degrees of supraspinal sympathetic vasomotor control. Responses of paraplegic subjects to head-up tilt were not significantly different from those of normal controls but GFR and RPF were significantly lower in quadriplegics in the supine position. With tilt, MAP and RPF decreased significantly, but the fall in GFR was not significant. In all 3 groups, the GFR during head-up tilt was similar, indicating that in spite of the great loss of supraspinal sympathetic control, quadriplegic subjects apparently equally-constrict their afferent and efferent renal arterioles during orthostatic stress and thus prevent excessive fall of GFR.

Adult↗
PubMed1981

Lower extremity fractures after spinal cord injury: a retrospective study.

Lower extremity fractures after spinal cord injury (SCI) are more common in paraplegic than in quadriplegic persons, probably due to their greater activity level. Most of the fractures are pathologic in osteoporotic bones and most occur without known trauma or are caused by trivial injury. Supracondylar or shaft fractures of the femur are most common. Although callus formation is usually fast, exuberant fracture healing may be delayed. The main management goal, maintenance of functional independence without complications of SCI, is best obtained by a nonsurgical approach with traction or well-padded cast followed by early joint mobilization.

Adolescent↗
PubMed1975

Pneumatic orthosis for paraplegic patients: functional evaluation and prescription considerations.

Fourteen paraplegic patients were studied during ambulation training, 11 with pneumatic orthoses and with conventional metal orthoses, and 3 with pneumatic orthoses only. The purposes of the study were to establish whether pneumatic orthoses could be used by paraplegic patients for effective ambulation, whether these devices presented any advantages or disadvantages over conventional orthoses and how their use would affect the expected level of rehabilitation and independence. As far as application, standing up, sitting down and ambulation within a rehabilitation center are concerned, similar skills and levels of independence were obtained with both types of orthoses. Reduced tendency for orthostatic hypotension, availability, light weight and better endurance make the pneumatic orthosis especially suitable for early ambulation training, but several mechanical problems, mainly its inflation with motorized and heavy compressor units, limit its usefulness for community ambulation.

Adolescent↗